Shari R. Lipner, MD, PhD

To the Editor:

Partial or total nail plate excisions commonly are used for the treatment of onychocryptosis and nail spicules. Procedures involving the nail unit require advanced technical skills to achieve optimal functional and aesthetic outcomes, avoid complications, and minimize health care costs. Data on the frequency of nail plate excisions performed by dermatologists and their relative frequency compared to other medical providers are limited. The objective of our study was to analyze trends in nail excision practice patterns among medical providers in the United States.

A retrospective analysis on nail excisions using the Current Procedural Terminology (CPT) code 11750 (excision of nail and nail matrix, partial or complete [eg, ingrown or deformed nail] for permanent removal), which is distinct from code 11755 (biopsy of nail unit [eg, plate, bed, matrix, hyponychium, proximal and lateral nail folds][separate procedure]), was performed using data from the Medicare Provider Utilization and Payment Database 2012-2017.^1,2 This file also is used by Peck et al³ in an article submitted to the Journal of the American Podiatric Medical Association and currently under consideration for publication. Procedures were recorded by year and provider type—dermatologist, podiatrist, physician assistant (PA)/nurse practitioner (NP), nondermatologist physician—and subcategorized by provider specialty (Table). Practice locations subcategorized by provider type were mapped using Tableau Software (Salesforce)(Figure). Descriptive statistics including number of providers, mean and median excisions per provider, and minimum/maximum nail excisions were calculated (Table). Practice types of PAs/NPs and specialization of nondermatologist physicians were determined using provider name, identification number, and practice address. This study did not require institutional review board review, as only publicly available data were utilized in our analysis.

A total of 6936 podiatrists, 58 nondermatologist physicians, 25 PAs/NPs, and 4 dermatologists performed 10 or more nail excisions annually under CPT code 11750 from January 2012 to December 2017 with annual means of 31, 31, 25, and 34, respectively (Table). No PAs/NPs included in the dataset worked in dermatology practices during the study period. Physician assistants and NPs most often practiced in podiatry and family medicine (FM) settings (both 40% [10/25]). Nondermatologist physicians most often specialized in FM (40% [23/58])(Table). The greatest number of providers practiced in 3 of the 4 most-populous states: California, Texas, and Florida; the fewest number practiced in 3 of the 10 least-populous states: Alaska, Hawaii, and Vermont. Vermont, Wyoming, and North Dakota—3 of the 5 least-populous states—had the fewest practitioners among the contiguous United States (Figure).

Figure generated using Tableau, which integrates with Mapbox. © Mapbox (https://www.mapbox.com/about/maps/), © OpenStreetMap (http://www.openstreetmap.org/copyright).

Our study showed that from January 2012 to December 2017, fewer dermatologists performed nail excisions than any other provider type (0.06%, 4 dermatologists of 7023 total providers), and dermatologists performed 1734-fold fewer nail excisions than podiatrists (99%, 6936 podiatrists of 7023 total providers). Only dermatologists practicing in California, Georgia, Indiana, and Oklahoma performed nail excisions. Conversely, podiatrists were more geographically distributed across the United States and other territories, with representation in all 50 states as well as the District of Columbia, Puerto Rico, and Guam.

Reasons for these large discrepancies in practice between dermatologists and other providers likely are multifactorial, encompassing a lack of emphasis on nail procedures in dermatology training, patient perception of the scope of dermatologic practice, and nail excision reimbursement patterns. Most dermatologists likely lack experience in performing nail procedures. The Accreditation Council for Graduate Medical Education requirements mandate that dermatology residents observe or perform 3 nail procedures over 3 years of residency, including 1 that may be performed on a human cadaver.⁴ In contrast, podiatry trainees must gain competency in toenail avulsion (both partial and complete), participate in anesthesia workshops, and become proficient in administering lower extremity blocks by the end of their training.⁵ Therefore, incorporating aspects of podiatric surgical training into dermatology residency requirements may increase the competency and comfort of dermatologists in performing nail excisions and practicing as nail experts as attending physicians.

It is likely that US patients do not perceive dermatologists as nail specialists and instead primarily consult podiatrists or FM and/or internal medicine physicians for treatment; for example, nail disease was one of the least common reasons for consulting a dermatologist (5%) in a German nationwide survey-based study (N=1015).⁶ Therefore, increased efforts are needed to educate the general public about the expertise of dermatologists in the diagnosis and management of nail conditions.

Reimbursement also may be a barrier to dermatologists performing nail procedures as part of their scope of practice; for example, in a retrospective study of nail biopsies using the Medicare Provider Utilization and Payment Database, there was no statistically significant difference in reimbursements for nail biopsies vs skin biopsies from 2012 to 2017 (P=0.69).⁷ Similar to nail biopsies, nail excisions typically are much more time consuming and technically demanding than skin biopsies, which may discourage dermatologists from routinely performing nail excision procedures.

Our study is subject to a number of limitations. The data reflected only US-based practice patterns and may not be applicable to nail procedures globally. There also is the potential for miscoding of procedures in the Medicare database. The data included only Part B Medicare fee-for-service and excludes non-Medicare insured, uninsured, and self-pay patients, as well as aggregated records from 10 or fewer Medicare beneficiaries.

Dermatologists rarely perform nail excisions and perform fewer nail excisions than any other provider type in the United States. There currently is an unmet need for comprehensive nail surgery education in US-based dermatology residency programs. We hope that our study fosters interdisciplinary collegiality and training between podiatrists and dermatologists and promotes expanded access to care across the United States to serve patients with nail disorders.

To the Editor:

Partial or total nail plate excisions commonly are used for the treatment of onychocryptosis and nail spicules. Procedures involving the nail unit require advanced technical skills to achieve optimal functional and aesthetic outcomes, avoid complications, and minimize health care costs. Data on the frequency of nail plate excisions performed by dermatologists and their relative frequency compared to other medical providers are limited. The objective of our study was to analyze trends in nail excision practice patterns among medical providers in the United States.

A retrospective analysis on nail excisions using the Current Procedural Terminology (CPT) code 11750 (excision of nail and nail matrix, partial or complete [eg, ingrown or deformed nail] for permanent removal), which is distinct from code 11755 (biopsy of nail unit [eg, plate, bed, matrix, hyponychium, proximal and lateral nail folds][separate procedure]), was performed using data from the Medicare Provider Utilization and Payment Database 2012-2017.^1,2 This file also is used by Peck et al³ in an article submitted to the Journal of the American Podiatric Medical Association and currently under consideration for publication. Procedures were recorded by year and provider type—dermatologist, podiatrist, physician assistant (PA)/nurse practitioner (NP), nondermatologist physician—and subcategorized by provider specialty (Table). Practice locations subcategorized by provider type were mapped using Tableau Software (Salesforce)(Figure). Descriptive statistics including number of providers, mean and median excisions per provider, and minimum/maximum nail excisions were calculated (Table). Practice types of PAs/NPs and specialization of nondermatologist physicians were determined using provider name, identification number, and practice address. This study did not require institutional review board review, as only publicly available data were utilized in our analysis.

A total of 6936 podiatrists, 58 nondermatologist physicians, 25 PAs/NPs, and 4 dermatologists performed 10 or more nail excisions annually under CPT code 11750 from January 2012 to December 2017 with annual means of 31, 31, 25, and 34, respectively (Table). No PAs/NPs included in the dataset worked in dermatology practices during the study period. Physician assistants and NPs most often practiced in podiatry and family medicine (FM) settings (both 40% [10/25]). Nondermatologist physicians most often specialized in FM (40% [23/58])(Table). The greatest number of providers practiced in 3 of the 4 most-populous states: California, Texas, and Florida; the fewest number practiced in 3 of the 10 least-populous states: Alaska, Hawaii, and Vermont. Vermont, Wyoming, and North Dakota—3 of the 5 least-populous states—had the fewest practitioners among the contiguous United States (Figure).

Figure generated using Tableau, which integrates with Mapbox. © Mapbox (https://www.mapbox.com/about/maps/), © OpenStreetMap (http://www.openstreetmap.org/copyright).

Our study showed that from January 2012 to December 2017, fewer dermatologists performed nail excisions than any other provider type (0.06%, 4 dermatologists of 7023 total providers), and dermatologists performed 1734-fold fewer nail excisions than podiatrists (99%, 6936 podiatrists of 7023 total providers). Only dermatologists practicing in California, Georgia, Indiana, and Oklahoma performed nail excisions. Conversely, podiatrists were more geographically distributed across the United States and other territories, with representation in all 50 states as well as the District of Columbia, Puerto Rico, and Guam.

Reasons for these large discrepancies in practice between dermatologists and other providers likely are multifactorial, encompassing a lack of emphasis on nail procedures in dermatology training, patient perception of the scope of dermatologic practice, and nail excision reimbursement patterns. Most dermatologists likely lack experience in performing nail procedures. The Accreditation Council for Graduate Medical Education requirements mandate that dermatology residents observe or perform 3 nail procedures over 3 years of residency, including 1 that may be performed on a human cadaver.⁴ In contrast, podiatry trainees must gain competency in toenail avulsion (both partial and complete), participate in anesthesia workshops, and become proficient in administering lower extremity blocks by the end of their training.⁵ Therefore, incorporating aspects of podiatric surgical training into dermatology residency requirements may increase the competency and comfort of dermatologists in performing nail excisions and practicing as nail experts as attending physicians.

It is likely that US patients do not perceive dermatologists as nail specialists and instead primarily consult podiatrists or FM and/or internal medicine physicians for treatment; for example, nail disease was one of the least common reasons for consulting a dermatologist (5%) in a German nationwide survey-based study (N=1015).⁶ Therefore, increased efforts are needed to educate the general public about the expertise of dermatologists in the diagnosis and management of nail conditions.

Reimbursement also may be a barrier to dermatologists performing nail procedures as part of their scope of practice; for example, in a retrospective study of nail biopsies using the Medicare Provider Utilization and Payment Database, there was no statistically significant difference in reimbursements for nail biopsies vs skin biopsies from 2012 to 2017 (P=0.69).⁷ Similar to nail biopsies, nail excisions typically are much more time consuming and technically demanding than skin biopsies, which may discourage dermatologists from routinely performing nail excision procedures.

Our study is subject to a number of limitations. The data reflected only US-based practice patterns and may not be applicable to nail procedures globally. There also is the potential for miscoding of procedures in the Medicare database. The data included only Part B Medicare fee-for-service and excludes non-Medicare insured, uninsured, and self-pay patients, as well as aggregated records from 10 or fewer Medicare beneficiaries.

Dermatologists rarely perform nail excisions and perform fewer nail excisions than any other provider type in the United States. There currently is an unmet need for comprehensive nail surgery education in US-based dermatology residency programs. We hope that our study fosters interdisciplinary collegiality and training between podiatrists and dermatologists and promotes expanded access to care across the United States to serve patients with nail disorders.

To the Editor:

Partial or total nail plate excisions commonly are used for the treatment of onychocryptosis and nail spicules. Procedures involving the nail unit require advanced technical skills to achieve optimal functional and aesthetic outcomes, avoid complications, and minimize health care costs. Data on the frequency of nail plate excisions performed by dermatologists and their relative frequency compared to other medical providers are limited. The objective of our study was to analyze trends in nail excision practice patterns among medical providers in the United States.

A retrospective analysis on nail excisions using the Current Procedural Terminology (CPT) code 11750 (excision of nail and nail matrix, partial or complete [eg, ingrown or deformed nail] for permanent removal), which is distinct from code 11755 (biopsy of nail unit [eg, plate, bed, matrix, hyponychium, proximal and lateral nail folds][separate procedure]), was performed using data from the Medicare Provider Utilization and Payment Database 2012-2017.^1,2 This file also is used by Peck et al³ in an article submitted to the Journal of the American Podiatric Medical Association and currently under consideration for publication. Procedures were recorded by year and provider type—dermatologist, podiatrist, physician assistant (PA)/nurse practitioner (NP), nondermatologist physician—and subcategorized by provider specialty (Table). Practice locations subcategorized by provider type were mapped using Tableau Software (Salesforce)(Figure). Descriptive statistics including number of providers, mean and median excisions per provider, and minimum/maximum nail excisions were calculated (Table). Practice types of PAs/NPs and specialization of nondermatologist physicians were determined using provider name, identification number, and practice address. This study did not require institutional review board review, as only publicly available data were utilized in our analysis.

A total of 6936 podiatrists, 58 nondermatologist physicians, 25 PAs/NPs, and 4 dermatologists performed 10 or more nail excisions annually under CPT code 11750 from January 2012 to December 2017 with annual means of 31, 31, 25, and 34, respectively (Table). No PAs/NPs included in the dataset worked in dermatology practices during the study period. Physician assistants and NPs most often practiced in podiatry and family medicine (FM) settings (both 40% [10/25]). Nondermatologist physicians most often specialized in FM (40% [23/58])(Table). The greatest number of providers practiced in 3 of the 4 most-populous states: California, Texas, and Florida; the fewest number practiced in 3 of the 10 least-populous states: Alaska, Hawaii, and Vermont. Vermont, Wyoming, and North Dakota—3 of the 5 least-populous states—had the fewest practitioners among the contiguous United States (Figure).

Figure generated using Tableau, which integrates with Mapbox. © Mapbox (https://www.mapbox.com/about/maps/), © OpenStreetMap (http://www.openstreetmap.org/copyright).

Our study showed that from January 2012 to December 2017, fewer dermatologists performed nail excisions than any other provider type (0.06%, 4 dermatologists of 7023 total providers), and dermatologists performed 1734-fold fewer nail excisions than podiatrists (99%, 6936 podiatrists of 7023 total providers). Only dermatologists practicing in California, Georgia, Indiana, and Oklahoma performed nail excisions. Conversely, podiatrists were more geographically distributed across the United States and other territories, with representation in all 50 states as well as the District of Columbia, Puerto Rico, and Guam.

Reasons for these large discrepancies in practice between dermatologists and other providers likely are multifactorial, encompassing a lack of emphasis on nail procedures in dermatology training, patient perception of the scope of dermatologic practice, and nail excision reimbursement patterns. Most dermatologists likely lack experience in performing nail procedures. The Accreditation Council for Graduate Medical Education requirements mandate that dermatology residents observe or perform 3 nail procedures over 3 years of residency, including 1 that may be performed on a human cadaver.⁴ In contrast, podiatry trainees must gain competency in toenail avulsion (both partial and complete), participate in anesthesia workshops, and become proficient in administering lower extremity blocks by the end of their training.⁵ Therefore, incorporating aspects of podiatric surgical training into dermatology residency requirements may increase the competency and comfort of dermatologists in performing nail excisions and practicing as nail experts as attending physicians.

It is likely that US patients do not perceive dermatologists as nail specialists and instead primarily consult podiatrists or FM and/or internal medicine physicians for treatment; for example, nail disease was one of the least common reasons for consulting a dermatologist (5%) in a German nationwide survey-based study (N=1015).⁶ Therefore, increased efforts are needed to educate the general public about the expertise of dermatologists in the diagnosis and management of nail conditions.

Reimbursement also may be a barrier to dermatologists performing nail procedures as part of their scope of practice; for example, in a retrospective study of nail biopsies using the Medicare Provider Utilization and Payment Database, there was no statistically significant difference in reimbursements for nail biopsies vs skin biopsies from 2012 to 2017 (P=0.69).⁷ Similar to nail biopsies, nail excisions typically are much more time consuming and technically demanding than skin biopsies, which may discourage dermatologists from routinely performing nail excision procedures.

Our study is subject to a number of limitations. The data reflected only US-based practice patterns and may not be applicable to nail procedures globally. There also is the potential for miscoding of procedures in the Medicare database. The data included only Part B Medicare fee-for-service and excludes non-Medicare insured, uninsured, and self-pay patients, as well as aggregated records from 10 or fewer Medicare beneficiaries.

Dermatologists rarely perform nail excisions and perform fewer nail excisions than any other provider type in the United States. There currently is an unmet need for comprehensive nail surgery education in US-based dermatology residency programs. We hope that our study fosters interdisciplinary collegiality and training between podiatrists and dermatologists and promotes expanded access to care across the United States to serve patients with nail disorders.

Practice Gap

Pain and anxiety are common in fully conscious patients undergoing dermatologic surgery with local anesthesia. Particularly during nail surgery, pain from anesthetic injection—caused by both needle insertion and fluid infiltration—occurs because the nail unit is highly vascularized and innervated.¹ Current methods to improve patient comfort during infiltration include use of a buffered anesthetic solution, warming the anesthetic, slower technique, and direct cold application.²

Perioperative anxiety correlates with increased postoperative pain, analgesic use, and delayed recovery. Furthermore, increased perioperative anxiety reduces the pain threshold and elevates estimates of pain intensity.³ Therefore, reducing procedure-related anxiety and pain may improve quality of care and ease patient discomfort.

Distraction is a common and practical nonpharmacotherapeutic technique for reducing pain and anxiety during medical procedures. The refocusing method of distraction aims to divert attention away from pain to more pleasant stimuli to reduce pain perception.³ Several methods of distraction—using stress balls, engaging in conversation, hand-holding, applying virtual reality, and playing videos—can decrease perioperative anxiety and pain.^3-6

Procedural pain and distraction techniques have been evaluated in the pediatric population more than in adults.⁴ Nail surgery–associated pain and distraction techniques for nail surgery have been inadequately studied.⁷

We offer a distraction technique utilizing a portable massager to ensure that patients are as comfortable as possible when the local anesthetic is injected prior to the first incision.

The Technique

A portable shiatsu massager that uses heat and deep-tissue kneading is placed on the upper thigh for toenail cases or lower arm for fingernail cases during injection of anesthetic to divert the patient’s attention from the surgical site (Figure). Kneading from the massage helps distract the patient from pain by introducing a competing, more pleasant, vibrating sensation that overrides pain signals; the relaxation component helps to diminish patient anxiety during injection.

Practice Implications

Use of a portable massager may reduce pain through both distraction and vibration. In a randomized clinical trial of 115 patients undergoing hand or facial surgery, patients who viewed a distraction video during the procedure reported a lower pain score compared to the control group (mean [SD] visual analog scale of pain score, 3.4 [2.6] vs 4.5 [2.6][P=.01]).⁴ In another randomized clinical trial of 25 patients undergoing lip augmentation, 92% of patients (23/25) in the vibration-assisted arm endorsed less pain during procedures compared to the arm without vibration (mean [SD] pain score, 3.82 [1.73] vs 5.6 [1.76][P<.001]).⁸

Utilization of a portable massager is a safe means of improving the patient experience; the distracting and relaxing effects and intense pulsations simultaneously reduce anxiety and pain during nail surgery. Controlled clinical trials are needed to evaluate its efficacy in diminishing both anxiety and pain during nail procedures compared to other analgesic methods.

Practice Gap

Pain and anxiety are common in fully conscious patients undergoing dermatologic surgery with local anesthesia. Particularly during nail surgery, pain from anesthetic injection—caused by both needle insertion and fluid infiltration—occurs because the nail unit is highly vascularized and innervated.¹ Current methods to improve patient comfort during infiltration include use of a buffered anesthetic solution, warming the anesthetic, slower technique, and direct cold application.²

Perioperative anxiety correlates with increased postoperative pain, analgesic use, and delayed recovery. Furthermore, increased perioperative anxiety reduces the pain threshold and elevates estimates of pain intensity.³ Therefore, reducing procedure-related anxiety and pain may improve quality of care and ease patient discomfort.

Distraction is a common and practical nonpharmacotherapeutic technique for reducing pain and anxiety during medical procedures. The refocusing method of distraction aims to divert attention away from pain to more pleasant stimuli to reduce pain perception.³ Several methods of distraction—using stress balls, engaging in conversation, hand-holding, applying virtual reality, and playing videos—can decrease perioperative anxiety and pain.^3-6

Procedural pain and distraction techniques have been evaluated in the pediatric population more than in adults.⁴ Nail surgery–associated pain and distraction techniques for nail surgery have been inadequately studied.⁷

We offer a distraction technique utilizing a portable massager to ensure that patients are as comfortable as possible when the local anesthetic is injected prior to the first incision.

The Technique

A portable shiatsu massager that uses heat and deep-tissue kneading is placed on the upper thigh for toenail cases or lower arm for fingernail cases during injection of anesthetic to divert the patient’s attention from the surgical site (Figure). Kneading from the massage helps distract the patient from pain by introducing a competing, more pleasant, vibrating sensation that overrides pain signals; the relaxation component helps to diminish patient anxiety during injection.

Practice Implications

Use of a portable massager may reduce pain through both distraction and vibration. In a randomized clinical trial of 115 patients undergoing hand or facial surgery, patients who viewed a distraction video during the procedure reported a lower pain score compared to the control group (mean [SD] visual analog scale of pain score, 3.4 [2.6] vs 4.5 [2.6][P=.01]).⁴ In another randomized clinical trial of 25 patients undergoing lip augmentation, 92% of patients (23/25) in the vibration-assisted arm endorsed less pain during procedures compared to the arm without vibration (mean [SD] pain score, 3.82 [1.73] vs 5.6 [1.76][P<.001]).⁸

Utilization of a portable massager is a safe means of improving the patient experience; the distracting and relaxing effects and intense pulsations simultaneously reduce anxiety and pain during nail surgery. Controlled clinical trials are needed to evaluate its efficacy in diminishing both anxiety and pain during nail procedures compared to other analgesic methods.

Practice Gap

Pain and anxiety are common in fully conscious patients undergoing dermatologic surgery with local anesthesia. Particularly during nail surgery, pain from anesthetic injection—caused by both needle insertion and fluid infiltration—occurs because the nail unit is highly vascularized and innervated.¹ Current methods to improve patient comfort during infiltration include use of a buffered anesthetic solution, warming the anesthetic, slower technique, and direct cold application.²

Perioperative anxiety correlates with increased postoperative pain, analgesic use, and delayed recovery. Furthermore, increased perioperative anxiety reduces the pain threshold and elevates estimates of pain intensity.³ Therefore, reducing procedure-related anxiety and pain may improve quality of care and ease patient discomfort.

Distraction is a common and practical nonpharmacotherapeutic technique for reducing pain and anxiety during medical procedures. The refocusing method of distraction aims to divert attention away from pain to more pleasant stimuli to reduce pain perception.³ Several methods of distraction—using stress balls, engaging in conversation, hand-holding, applying virtual reality, and playing videos—can decrease perioperative anxiety and pain.^3-6

Procedural pain and distraction techniques have been evaluated in the pediatric population more than in adults.⁴ Nail surgery–associated pain and distraction techniques for nail surgery have been inadequately studied.⁷

We offer a distraction technique utilizing a portable massager to ensure that patients are as comfortable as possible when the local anesthetic is injected prior to the first incision.

The Technique

A portable shiatsu massager that uses heat and deep-tissue kneading is placed on the upper thigh for toenail cases or lower arm for fingernail cases during injection of anesthetic to divert the patient’s attention from the surgical site (Figure). Kneading from the massage helps distract the patient from pain by introducing a competing, more pleasant, vibrating sensation that overrides pain signals; the relaxation component helps to diminish patient anxiety during injection.

Practice Implications

Use of a portable massager may reduce pain through both distraction and vibration. In a randomized clinical trial of 115 patients undergoing hand or facial surgery, patients who viewed a distraction video during the procedure reported a lower pain score compared to the control group (mean [SD] visual analog scale of pain score, 3.4 [2.6] vs 4.5 [2.6][P=.01]).⁴ In another randomized clinical trial of 25 patients undergoing lip augmentation, 92% of patients (23/25) in the vibration-assisted arm endorsed less pain during procedures compared to the arm without vibration (mean [SD] pain score, 3.82 [1.73] vs 5.6 [1.76][P<.001]).⁸

Utilization of a portable massager is a safe means of improving the patient experience; the distracting and relaxing effects and intense pulsations simultaneously reduce anxiety and pain during nail surgery. Controlled clinical trials are needed to evaluate its efficacy in diminishing both anxiety and pain during nail procedures compared to other analgesic methods.

Nail surgical procedures including biopsies, correction of onychocryptosis and other deformities, and excision of tumors are essential for diagnosing and treating nail disorders. Nail surgery often is perceived by dermatologists as a difficult-to-perform, high-risk procedure associated with patient anxiety, pain, and permanent scarring, which may limit implementation. Misconceptions about nail surgical techniques, aftercare, and patient outcomes are prevalent, and a paucity of nail surgery randomized clinical trials hinder formulation of standardized guidelines.¹ In a survey-based study of 95 dermatology residency programs (240 total respondents), 58% of residents said they performed 10 or fewer nail procedures, 10% performed more than 10 procedures, 25% only observed nail procedures, 4% were exposed by lecture only, and 1% had no exposure; 30% said they felt incompetent performing nail biopsies.² In a retrospective study of nail biopsies performed from 2012 to 2017 in the Medicare Provider Utilization and Payment Database, only 0.28% and 1.01% of all general dermatologists and Mohs surgeons, respectively, performed nail biopsies annually.³ A minimally invasive nail surgery technique is essential to alleviating dermatologist and patient apprehension, which may lead to greater adoption and improved outcomes.

Reduce Patient Anxiety During Nail Surgery

The prospect of undergoing nail surgery can be psychologically distressing to patients because the nail unit is highly sensitive, intraoperative and postoperative pain are common concerns, patient education materials generally are scarce and inaccurate,⁴ and procedures are performed under local anesthesia with the patient fully awake. In a prospective study of 48 patients undergoing nail surgery, the median preoperative Spielberger State-Trait Anxiety Inventory level was 42.00 (IQR, 6.50).⁵ Patient distress may be minimized by providing verbal and written educational materials, discussing expectations, and preoperatively using fast-acting benzodiazepines when necessary.⁶ Utilizing a sleep mask,⁷ stress ball,⁸ music,⁹ and/or virtual reality¹⁰ also may reduce patient anxiety during nail surgery.

Use Proper Anesthetic Techniques

Proper anesthetic technique is crucial to achieve the optimal patient experience during nail surgery. With a wing block, the anesthetic is injected into 3 points: (1) the proximal nail fold, (2) the medial/lateral fold, and (3) the hyponychium. The wing block is the preferred technique by many nail surgeons because the second and third injections are given in skin that is already anesthetized, reducing patient discomfort to a single pinprick¹¹; additionally, there is lower postoperative paresthesia risk with the wing block compared with other digital nerve blocks.¹² Ropivacaine, a fast-acting and long-acting anesthetic, is preferred over lidocaine to minimize immediate postoperative pain. Buffering the anesthetic solution to physiologic pH and slow infiltration can reduce pain during infiltration.¹² Distraction¹² provided by ethyl chloride refrigerant spray, an air-cooling device,¹³ or vibration also can reduce pain during anesthesia.

Punch Biopsy and Excision Tips

The punch biopsy is a minimally invasive method for diagnosing various neoplastic and inflammatory nail unit conditions, except for pigmented lesions.¹² For polydactylous nail conditions requiring biopsy, a digit on the nondominant hand should be selected if possible. The punch is applied directly to the nail plate and twisted with downward pressure until the bone is reached, with the instrument withdrawn slowly to prevent surrounding nail plate detachment. Hemostasis is easily achieved with direct pressure and/or use of epinephrine or ropivacaine during anesthesia, and a digital tourniquet generally is not required. Applying microporous polysaccharide hemospheres powder¹⁴ or kaolin-impregnated gauze¹⁵ with direct pressure is helpful in managing continued bleeding following nail surgery. Punching through the proximal nail matrix should be avoided to prevent permanent onychodystrophy.

A tangential matrix shave biopsy requires a more practiced technique and is preferred for sampling longitudinal melanonychia. A partial proximal nail plate avulsion adequately exposes the origin of pigment and avoids complete avulsion, which may cause more onychodystrophy.¹⁶ For broad erythronychia, a total nail avulsion may be necessary. For narrow, well-defined erythronychia, a less-invasive approach such as trap-door avulsion, longitudinal nail strip, or lateral nail plate curl, depending on the etiology, often is sufficient. Tissue excision should be tailored to the specific etiology, with localized excision sufficient for glomus tumors; onychopapillomas require tangential excision of the distal matrix, entire nail bed, and hyperkeratotic papule at the hyponychium. Pushing the cuticle with an elevator/spatula instead of making 2 tangential incisions on the proximal nail fold has been suggested to decrease postoperative paronychia risk.¹² A Teflon-coated blade is used to achieve a smooth cut with minimal drag, enabling collection of specimens less than 1 mm thick, which provides sufficient nail matrix epithelium and dermis for histologic examination.¹⁶ After obtaining the specimen, the avulsed nail plate may be sutured back to the nail bed using a rapidly absorbable suture such as polyglactin 910, serving as a temporary biological dressing and splint for the nail unit during healing.¹² In a retrospective study of 30 patients with longitudinal melanonychia undergoing tangential matrix excision, 27% (8/30) developed postoperative onychodystrophy.¹⁷ Although this technique carries relatively lower risk of permanent onychodystrophy compared to other methods, it still is important to acknowledge during the preoperative consent process.¹²

The lateral longitudinal excision is a valuable technique for diagnosing nail unit inflammatory conditions. Classically, a longitudinal sample including the proximal nail fold, complete matrix, lateral plate, lateral nail fold, hyponychium, and distal tip skin is obtained, with a 10% narrowing of the nail plate expected. If the lateral horn of the nail matrix is missed, permanent lateral malalignment and spicule formation are potential risks. To minimize narrowing of the nail plate and postoperative paronychia, a longitudinal nail strip—where the proximal nail fold and matrix are left intact—is an alternative technique.¹⁸

Pain Management Approaches

Appropriate postoperative pain management is crucial for optimizing patient outcomes. In a prospective study of 20 patients undergoing nail biopsy, the mean pain score 6 to 12 hours postprocedure was 5.7 on a scale of 0 to 10. Patients with presurgery pain vs those without experienced significantly higher pain levels both during anesthesia and after surgery (both P<.05).¹⁹ Therefore, a personalized approach to pain management based on presence of presurgical pain is warranted. In a randomized clinical trial of 16 patients anesthetized with lidocaine 2% and intraoperative infiltration with a combination of ropivacaine 0.5 mL and triamcinolone (10 mg/mL [0.5 mL]) vs lidocaine 2% alone, the intraoperative mixture reduced postoperative pain (mean pain score, 2 of 10 at 48 hours postprocedure vs 7.88 of 10 in the control group [P<.001]).²⁰

A Cochrane review of 4 unpublished dental and orthopedic surgery studies showed that gabapentin is superior to placebo in the treatment of acute postoperative pain. Therefore, a single dose of gabapentin (250 mg) may be considered in patients at risk for high postoperative pain.²¹ In a randomized double-blind trial of 210 Mohs micrographic surgery patients, those receiving acetaminophen and ibuprofen reported lower pain scores at 2, 4, 8, and 12 hours postprocedure compared with patients taking acetaminophen and codeine or acetaminophen alone.²² However, the role of opioids in pain management following nail surgery has not been adequately studied.

Wound Care

An efficient dressing protects the surgical wound, facilitates healing, and provides comfort. In our experience, an initial layer of petrolatum-impregnated gauze followed by a pressure-padded bandage consisting of folded dry gauze secured in place with longitudinally applied tape to avoid a tourniquet effect is effective for nail surgical wounds. As the last step, self-adherent elastic wrap is applied around the digit and extended proximally to prevent a tourniquet effect.²³

Final Thoughts

Due to the intricate anatomy of the nail unit, nail surgeries are inherently more invasive than most dermatologic surgical procedures. It is crucial to adopt a minimally invasive approach to reduce tissue damage and potential complications in both the short-term and long-term. Adopting this approach may substantially improve patient outcomes and enhance diagnostic and treatment efficacy.

Nail surgical procedures including biopsies, correction of onychocryptosis and other deformities, and excision of tumors are essential for diagnosing and treating nail disorders. Nail surgery often is perceived by dermatologists as a difficult-to-perform, high-risk procedure associated with patient anxiety, pain, and permanent scarring, which may limit implementation. Misconceptions about nail surgical techniques, aftercare, and patient outcomes are prevalent, and a paucity of nail surgery randomized clinical trials hinder formulation of standardized guidelines.¹ In a survey-based study of 95 dermatology residency programs (240 total respondents), 58% of residents said they performed 10 or fewer nail procedures, 10% performed more than 10 procedures, 25% only observed nail procedures, 4% were exposed by lecture only, and 1% had no exposure; 30% said they felt incompetent performing nail biopsies.² In a retrospective study of nail biopsies performed from 2012 to 2017 in the Medicare Provider Utilization and Payment Database, only 0.28% and 1.01% of all general dermatologists and Mohs surgeons, respectively, performed nail biopsies annually.³ A minimally invasive nail surgery technique is essential to alleviating dermatologist and patient apprehension, which may lead to greater adoption and improved outcomes.

Reduce Patient Anxiety During Nail Surgery

The prospect of undergoing nail surgery can be psychologically distressing to patients because the nail unit is highly sensitive, intraoperative and postoperative pain are common concerns, patient education materials generally are scarce and inaccurate,⁴ and procedures are performed under local anesthesia with the patient fully awake. In a prospective study of 48 patients undergoing nail surgery, the median preoperative Spielberger State-Trait Anxiety Inventory level was 42.00 (IQR, 6.50).⁵ Patient distress may be minimized by providing verbal and written educational materials, discussing expectations, and preoperatively using fast-acting benzodiazepines when necessary.⁶ Utilizing a sleep mask,⁷ stress ball,⁸ music,⁹ and/or virtual reality¹⁰ also may reduce patient anxiety during nail surgery.

Use Proper Anesthetic Techniques

Proper anesthetic technique is crucial to achieve the optimal patient experience during nail surgery. With a wing block, the anesthetic is injected into 3 points: (1) the proximal nail fold, (2) the medial/lateral fold, and (3) the hyponychium. The wing block is the preferred technique by many nail surgeons because the second and third injections are given in skin that is already anesthetized, reducing patient discomfort to a single pinprick¹¹; additionally, there is lower postoperative paresthesia risk with the wing block compared with other digital nerve blocks.¹² Ropivacaine, a fast-acting and long-acting anesthetic, is preferred over lidocaine to minimize immediate postoperative pain. Buffering the anesthetic solution to physiologic pH and slow infiltration can reduce pain during infiltration.¹² Distraction¹² provided by ethyl chloride refrigerant spray, an air-cooling device,¹³ or vibration also can reduce pain during anesthesia.

Punch Biopsy and Excision Tips

The punch biopsy is a minimally invasive method for diagnosing various neoplastic and inflammatory nail unit conditions, except for pigmented lesions.¹² For polydactylous nail conditions requiring biopsy, a digit on the nondominant hand should be selected if possible. The punch is applied directly to the nail plate and twisted with downward pressure until the bone is reached, with the instrument withdrawn slowly to prevent surrounding nail plate detachment. Hemostasis is easily achieved with direct pressure and/or use of epinephrine or ropivacaine during anesthesia, and a digital tourniquet generally is not required. Applying microporous polysaccharide hemospheres powder¹⁴ or kaolin-impregnated gauze¹⁵ with direct pressure is helpful in managing continued bleeding following nail surgery. Punching through the proximal nail matrix should be avoided to prevent permanent onychodystrophy.

A tangential matrix shave biopsy requires a more practiced technique and is preferred for sampling longitudinal melanonychia. A partial proximal nail plate avulsion adequately exposes the origin of pigment and avoids complete avulsion, which may cause more onychodystrophy.¹⁶ For broad erythronychia, a total nail avulsion may be necessary. For narrow, well-defined erythronychia, a less-invasive approach such as trap-door avulsion, longitudinal nail strip, or lateral nail plate curl, depending on the etiology, often is sufficient. Tissue excision should be tailored to the specific etiology, with localized excision sufficient for glomus tumors; onychopapillomas require tangential excision of the distal matrix, entire nail bed, and hyperkeratotic papule at the hyponychium. Pushing the cuticle with an elevator/spatula instead of making 2 tangential incisions on the proximal nail fold has been suggested to decrease postoperative paronychia risk.¹² A Teflon-coated blade is used to achieve a smooth cut with minimal drag, enabling collection of specimens less than 1 mm thick, which provides sufficient nail matrix epithelium and dermis for histologic examination.¹⁶ After obtaining the specimen, the avulsed nail plate may be sutured back to the nail bed using a rapidly absorbable suture such as polyglactin 910, serving as a temporary biological dressing and splint for the nail unit during healing.¹² In a retrospective study of 30 patients with longitudinal melanonychia undergoing tangential matrix excision, 27% (8/30) developed postoperative onychodystrophy.¹⁷ Although this technique carries relatively lower risk of permanent onychodystrophy compared to other methods, it still is important to acknowledge during the preoperative consent process.¹²

The lateral longitudinal excision is a valuable technique for diagnosing nail unit inflammatory conditions. Classically, a longitudinal sample including the proximal nail fold, complete matrix, lateral plate, lateral nail fold, hyponychium, and distal tip skin is obtained, with a 10% narrowing of the nail plate expected. If the lateral horn of the nail matrix is missed, permanent lateral malalignment and spicule formation are potential risks. To minimize narrowing of the nail plate and postoperative paronychia, a longitudinal nail strip—where the proximal nail fold and matrix are left intact—is an alternative technique.¹⁸

Pain Management Approaches

Appropriate postoperative pain management is crucial for optimizing patient outcomes. In a prospective study of 20 patients undergoing nail biopsy, the mean pain score 6 to 12 hours postprocedure was 5.7 on a scale of 0 to 10. Patients with presurgery pain vs those without experienced significantly higher pain levels both during anesthesia and after surgery (both P<.05).¹⁹ Therefore, a personalized approach to pain management based on presence of presurgical pain is warranted. In a randomized clinical trial of 16 patients anesthetized with lidocaine 2% and intraoperative infiltration with a combination of ropivacaine 0.5 mL and triamcinolone (10 mg/mL [0.5 mL]) vs lidocaine 2% alone, the intraoperative mixture reduced postoperative pain (mean pain score, 2 of 10 at 48 hours postprocedure vs 7.88 of 10 in the control group [P<.001]).²⁰

A Cochrane review of 4 unpublished dental and orthopedic surgery studies showed that gabapentin is superior to placebo in the treatment of acute postoperative pain. Therefore, a single dose of gabapentin (250 mg) may be considered in patients at risk for high postoperative pain.²¹ In a randomized double-blind trial of 210 Mohs micrographic surgery patients, those receiving acetaminophen and ibuprofen reported lower pain scores at 2, 4, 8, and 12 hours postprocedure compared with patients taking acetaminophen and codeine or acetaminophen alone.²² However, the role of opioids in pain management following nail surgery has not been adequately studied.

Wound Care

An efficient dressing protects the surgical wound, facilitates healing, and provides comfort. In our experience, an initial layer of petrolatum-impregnated gauze followed by a pressure-padded bandage consisting of folded dry gauze secured in place with longitudinally applied tape to avoid a tourniquet effect is effective for nail surgical wounds. As the last step, self-adherent elastic wrap is applied around the digit and extended proximally to prevent a tourniquet effect.²³

Final Thoughts

Due to the intricate anatomy of the nail unit, nail surgeries are inherently more invasive than most dermatologic surgical procedures. It is crucial to adopt a minimally invasive approach to reduce tissue damage and potential complications in both the short-term and long-term. Adopting this approach may substantially improve patient outcomes and enhance diagnostic and treatment efficacy.

Nail surgical procedures including biopsies, correction of onychocryptosis and other deformities, and excision of tumors are essential for diagnosing and treating nail disorders. Nail surgery often is perceived by dermatologists as a difficult-to-perform, high-risk procedure associated with patient anxiety, pain, and permanent scarring, which may limit implementation. Misconceptions about nail surgical techniques, aftercare, and patient outcomes are prevalent, and a paucity of nail surgery randomized clinical trials hinder formulation of standardized guidelines.¹ In a survey-based study of 95 dermatology residency programs (240 total respondents), 58% of residents said they performed 10 or fewer nail procedures, 10% performed more than 10 procedures, 25% only observed nail procedures, 4% were exposed by lecture only, and 1% had no exposure; 30% said they felt incompetent performing nail biopsies.² In a retrospective study of nail biopsies performed from 2012 to 2017 in the Medicare Provider Utilization and Payment Database, only 0.28% and 1.01% of all general dermatologists and Mohs surgeons, respectively, performed nail biopsies annually.³ A minimally invasive nail surgery technique is essential to alleviating dermatologist and patient apprehension, which may lead to greater adoption and improved outcomes.

Reduce Patient Anxiety During Nail Surgery

The prospect of undergoing nail surgery can be psychologically distressing to patients because the nail unit is highly sensitive, intraoperative and postoperative pain are common concerns, patient education materials generally are scarce and inaccurate,⁴ and procedures are performed under local anesthesia with the patient fully awake. In a prospective study of 48 patients undergoing nail surgery, the median preoperative Spielberger State-Trait Anxiety Inventory level was 42.00 (IQR, 6.50).⁵ Patient distress may be minimized by providing verbal and written educational materials, discussing expectations, and preoperatively using fast-acting benzodiazepines when necessary.⁶ Utilizing a sleep mask,⁷ stress ball,⁸ music,⁹ and/or virtual reality¹⁰ also may reduce patient anxiety during nail surgery.

Use Proper Anesthetic Techniques

Proper anesthetic technique is crucial to achieve the optimal patient experience during nail surgery. With a wing block, the anesthetic is injected into 3 points: (1) the proximal nail fold, (2) the medial/lateral fold, and (3) the hyponychium. The wing block is the preferred technique by many nail surgeons because the second and third injections are given in skin that is already anesthetized, reducing patient discomfort to a single pinprick¹¹; additionally, there is lower postoperative paresthesia risk with the wing block compared with other digital nerve blocks.¹² Ropivacaine, a fast-acting and long-acting anesthetic, is preferred over lidocaine to minimize immediate postoperative pain. Buffering the anesthetic solution to physiologic pH and slow infiltration can reduce pain during infiltration.¹² Distraction¹² provided by ethyl chloride refrigerant spray, an air-cooling device,¹³ or vibration also can reduce pain during anesthesia.

Punch Biopsy and Excision Tips

The punch biopsy is a minimally invasive method for diagnosing various neoplastic and inflammatory nail unit conditions, except for pigmented lesions.¹² For polydactylous nail conditions requiring biopsy, a digit on the nondominant hand should be selected if possible. The punch is applied directly to the nail plate and twisted with downward pressure until the bone is reached, with the instrument withdrawn slowly to prevent surrounding nail plate detachment. Hemostasis is easily achieved with direct pressure and/or use of epinephrine or ropivacaine during anesthesia, and a digital tourniquet generally is not required. Applying microporous polysaccharide hemospheres powder¹⁴ or kaolin-impregnated gauze¹⁵ with direct pressure is helpful in managing continued bleeding following nail surgery. Punching through the proximal nail matrix should be avoided to prevent permanent onychodystrophy.

A tangential matrix shave biopsy requires a more practiced technique and is preferred for sampling longitudinal melanonychia. A partial proximal nail plate avulsion adequately exposes the origin of pigment and avoids complete avulsion, which may cause more onychodystrophy.¹⁶ For broad erythronychia, a total nail avulsion may be necessary. For narrow, well-defined erythronychia, a less-invasive approach such as trap-door avulsion, longitudinal nail strip, or lateral nail plate curl, depending on the etiology, often is sufficient. Tissue excision should be tailored to the specific etiology, with localized excision sufficient for glomus tumors; onychopapillomas require tangential excision of the distal matrix, entire nail bed, and hyperkeratotic papule at the hyponychium. Pushing the cuticle with an elevator/spatula instead of making 2 tangential incisions on the proximal nail fold has been suggested to decrease postoperative paronychia risk.¹² A Teflon-coated blade is used to achieve a smooth cut with minimal drag, enabling collection of specimens less than 1 mm thick, which provides sufficient nail matrix epithelium and dermis for histologic examination.¹⁶ After obtaining the specimen, the avulsed nail plate may be sutured back to the nail bed using a rapidly absorbable suture such as polyglactin 910, serving as a temporary biological dressing and splint for the nail unit during healing.¹² In a retrospective study of 30 patients with longitudinal melanonychia undergoing tangential matrix excision, 27% (8/30) developed postoperative onychodystrophy.¹⁷ Although this technique carries relatively lower risk of permanent onychodystrophy compared to other methods, it still is important to acknowledge during the preoperative consent process.¹²

The lateral longitudinal excision is a valuable technique for diagnosing nail unit inflammatory conditions. Classically, a longitudinal sample including the proximal nail fold, complete matrix, lateral plate, lateral nail fold, hyponychium, and distal tip skin is obtained, with a 10% narrowing of the nail plate expected. If the lateral horn of the nail matrix is missed, permanent lateral malalignment and spicule formation are potential risks. To minimize narrowing of the nail plate and postoperative paronychia, a longitudinal nail strip—where the proximal nail fold and matrix are left intact—is an alternative technique.¹⁸

Pain Management Approaches

Appropriate postoperative pain management is crucial for optimizing patient outcomes. In a prospective study of 20 patients undergoing nail biopsy, the mean pain score 6 to 12 hours postprocedure was 5.7 on a scale of 0 to 10. Patients with presurgery pain vs those without experienced significantly higher pain levels both during anesthesia and after surgery (both P<.05).¹⁹ Therefore, a personalized approach to pain management based on presence of presurgical pain is warranted. In a randomized clinical trial of 16 patients anesthetized with lidocaine 2% and intraoperative infiltration with a combination of ropivacaine 0.5 mL and triamcinolone (10 mg/mL [0.5 mL]) vs lidocaine 2% alone, the intraoperative mixture reduced postoperative pain (mean pain score, 2 of 10 at 48 hours postprocedure vs 7.88 of 10 in the control group [P<.001]).²⁰

A Cochrane review of 4 unpublished dental and orthopedic surgery studies showed that gabapentin is superior to placebo in the treatment of acute postoperative pain. Therefore, a single dose of gabapentin (250 mg) may be considered in patients at risk for high postoperative pain.²¹ In a randomized double-blind trial of 210 Mohs micrographic surgery patients, those receiving acetaminophen and ibuprofen reported lower pain scores at 2, 4, 8, and 12 hours postprocedure compared with patients taking acetaminophen and codeine or acetaminophen alone.²² However, the role of opioids in pain management following nail surgery has not been adequately studied.

Wound Care

An efficient dressing protects the surgical wound, facilitates healing, and provides comfort. In our experience, an initial layer of petrolatum-impregnated gauze followed by a pressure-padded bandage consisting of folded dry gauze secured in place with longitudinally applied tape to avoid a tourniquet effect is effective for nail surgical wounds. As the last step, self-adherent elastic wrap is applied around the digit and extended proximally to prevent a tourniquet effect.²³

Final Thoughts

Due to the intricate anatomy of the nail unit, nail surgeries are inherently more invasive than most dermatologic surgical procedures. It is crucial to adopt a minimally invasive approach to reduce tissue damage and potential complications in both the short-term and long-term. Adopting this approach may substantially improve patient outcomes and enhance diagnostic and treatment efficacy.

To the Editor:

Citation number and Hirsch index (h-index) have long been employed as metrics of productivity for academic scholarship. The h-index is defined as the highest number of publications (the maximum h value) of an author who has published at least h papers, each cited by other authors at least h times.¹ In a bibliometric analysis of the most frequently cited authors in dermatology from 1974 to 2019 (N=378,276), females comprised 12% of first and 11% of senior authors of the most cited publications, and 6 of the most cited authors in dermatology were women.² In another study analyzing the most prolific dermatologic authors based on h-index, 0% from 1980 to 1989 and 19% from 2010 to 2019 were female (N=393,488).³ Because citation number and h-index favor longer-practicing dermatologists, we examined dermatology author productivity and gender trends by recent publication rates.

The Scopus database was searched for dermatology publications by using the field category “dermatology”from January 1, 2017, to October 7, 2022. Nondermatologists and authors with the same initials were excluded. Authors were ranked by number of publications, including original articles, case reports, letters, and reviews. Sex, degree, and years of experience were determined via a Google search of the author’s name. The h-index; number of citations; and percentages of first, middle, and last authorship were recorded.

Of the top 50 published dermatologists, 30% were female (n=15) and 56% (n=28) held both MD and PhD degrees (Table). The mean years of experience was 26.27 years (range, 6–44 years), with a mean of 29.23 years in females and 25.87 years in males. The mean h-index was 27.96 (range, 8–88), with 24.87 for females and 29.29 for males. The mean number of citations was 4032.64 (range, 235–36,908), with 2891.13 for females and 4521.86 for males. Thirty-one authors were most frequently middle authors, 18 were senior authors, and 1 was a first author. On average (SD), authors were senior or first author in 47.97% (20.08%) of their publications (range, 6.32%–94.93%).

Our study shows that females were more highly represented as top dermatology authors (30%) as measured by publication numbers from 2017 to 2022 than in studies measuring citation rate from 1974 to 2019 (12%)² or h-index from 2010 to 2019 (19%).³ Similarly, in a study of dermatology authorship from 2009 to 2019, on average, females represented 51.06% first and 38.18% last authors.⁴

The proportion of females in the dermatology workforce has increased, with 3964 of 10,385 (38.2%) active dermatologists in 2007⁵ being female vs 6372 of 12,505 (51.0%) in 2019.⁶ The lower proportion of practicing female dermatologists in earlier years likely accounts for the lower percentage of females in dermatology citations and h-index top lists during that time, given that citation and h-index metrics are biased to dermatologists with longer careers.

Although our data are encouraging, females still accounted for less than one-third of the top 50 authors by publication numbers. Gender inequalities persist, with only one-third of a total of 1292 National Institutes of Health dermatology grants and one-fourth of Research Project Grant Program (R01) grants being awarded to females in the years 2009 to 2014.⁷ Therefore, formal and informal mentorship, protected time for research, resources for childcare, and opportunities for funding will be critical in supporting female dermatologists to both publish highly impactful research and obtain research grants.

Limitations of our study include the omission of authors with identical initials and the inability to account for name changes. Furthermore, Scopus does not include all articles published by each author. Finally, publication number reflects quantity but may not reflect quality.

By quantitating dermatology author publication numbers, we found better representation of female authors compared with studies measuring citation number and h-index. With higher proportions of female dermatology trainees and efforts to increase mentorship and research support for female dermatologists, we expect improved equality in top lists of dermatology citations and h-index values.

To the Editor:

Citation number and Hirsch index (h-index) have long been employed as metrics of productivity for academic scholarship. The h-index is defined as the highest number of publications (the maximum h value) of an author who has published at least h papers, each cited by other authors at least h times.¹ In a bibliometric analysis of the most frequently cited authors in dermatology from 1974 to 2019 (N=378,276), females comprised 12% of first and 11% of senior authors of the most cited publications, and 6 of the most cited authors in dermatology were women.² In another study analyzing the most prolific dermatologic authors based on h-index, 0% from 1980 to 1989 and 19% from 2010 to 2019 were female (N=393,488).³ Because citation number and h-index favor longer-practicing dermatologists, we examined dermatology author productivity and gender trends by recent publication rates.

The Scopus database was searched for dermatology publications by using the field category “dermatology”from January 1, 2017, to October 7, 2022. Nondermatologists and authors with the same initials were excluded. Authors were ranked by number of publications, including original articles, case reports, letters, and reviews. Sex, degree, and years of experience were determined via a Google search of the author’s name. The h-index; number of citations; and percentages of first, middle, and last authorship were recorded.

Of the top 50 published dermatologists, 30% were female (n=15) and 56% (n=28) held both MD and PhD degrees (Table). The mean years of experience was 26.27 years (range, 6–44 years), with a mean of 29.23 years in females and 25.87 years in males. The mean h-index was 27.96 (range, 8–88), with 24.87 for females and 29.29 for males. The mean number of citations was 4032.64 (range, 235–36,908), with 2891.13 for females and 4521.86 for males. Thirty-one authors were most frequently middle authors, 18 were senior authors, and 1 was a first author. On average (SD), authors were senior or first author in 47.97% (20.08%) of their publications (range, 6.32%–94.93%).

Our study shows that females were more highly represented as top dermatology authors (30%) as measured by publication numbers from 2017 to 2022 than in studies measuring citation rate from 1974 to 2019 (12%)² or h-index from 2010 to 2019 (19%).³ Similarly, in a study of dermatology authorship from 2009 to 2019, on average, females represented 51.06% first and 38.18% last authors.⁴

The proportion of females in the dermatology workforce has increased, with 3964 of 10,385 (38.2%) active dermatologists in 2007⁵ being female vs 6372 of 12,505 (51.0%) in 2019.⁶ The lower proportion of practicing female dermatologists in earlier years likely accounts for the lower percentage of females in dermatology citations and h-index top lists during that time, given that citation and h-index metrics are biased to dermatologists with longer careers.

Although our data are encouraging, females still accounted for less than one-third of the top 50 authors by publication numbers. Gender inequalities persist, with only one-third of a total of 1292 National Institutes of Health dermatology grants and one-fourth of Research Project Grant Program (R01) grants being awarded to females in the years 2009 to 2014.⁷ Therefore, formal and informal mentorship, protected time for research, resources for childcare, and opportunities for funding will be critical in supporting female dermatologists to both publish highly impactful research and obtain research grants.

Limitations of our study include the omission of authors with identical initials and the inability to account for name changes. Furthermore, Scopus does not include all articles published by each author. Finally, publication number reflects quantity but may not reflect quality.

By quantitating dermatology author publication numbers, we found better representation of female authors compared with studies measuring citation number and h-index. With higher proportions of female dermatology trainees and efforts to increase mentorship and research support for female dermatologists, we expect improved equality in top lists of dermatology citations and h-index values.

To the Editor:

Citation number and Hirsch index (h-index) have long been employed as metrics of productivity for academic scholarship. The h-index is defined as the highest number of publications (the maximum h value) of an author who has published at least h papers, each cited by other authors at least h times.¹ In a bibliometric analysis of the most frequently cited authors in dermatology from 1974 to 2019 (N=378,276), females comprised 12% of first and 11% of senior authors of the most cited publications, and 6 of the most cited authors in dermatology were women.² In another study analyzing the most prolific dermatologic authors based on h-index, 0% from 1980 to 1989 and 19% from 2010 to 2019 were female (N=393,488).³ Because citation number and h-index favor longer-practicing dermatologists, we examined dermatology author productivity and gender trends by recent publication rates.

The Scopus database was searched for dermatology publications by using the field category “dermatology”from January 1, 2017, to October 7, 2022. Nondermatologists and authors with the same initials were excluded. Authors were ranked by number of publications, including original articles, case reports, letters, and reviews. Sex, degree, and years of experience were determined via a Google search of the author’s name. The h-index; number of citations; and percentages of first, middle, and last authorship were recorded.

Of the top 50 published dermatologists, 30% were female (n=15) and 56% (n=28) held both MD and PhD degrees (Table). The mean years of experience was 26.27 years (range, 6–44 years), with a mean of 29.23 years in females and 25.87 years in males. The mean h-index was 27.96 (range, 8–88), with 24.87 for females and 29.29 for males. The mean number of citations was 4032.64 (range, 235–36,908), with 2891.13 for females and 4521.86 for males. Thirty-one authors were most frequently middle authors, 18 were senior authors, and 1 was a first author. On average (SD), authors were senior or first author in 47.97% (20.08%) of their publications (range, 6.32%–94.93%).

Our study shows that females were more highly represented as top dermatology authors (30%) as measured by publication numbers from 2017 to 2022 than in studies measuring citation rate from 1974 to 2019 (12%)² or h-index from 2010 to 2019 (19%).³ Similarly, in a study of dermatology authorship from 2009 to 2019, on average, females represented 51.06% first and 38.18% last authors.⁴

The proportion of females in the dermatology workforce has increased, with 3964 of 10,385 (38.2%) active dermatologists in 2007⁵ being female vs 6372 of 12,505 (51.0%) in 2019.⁶ The lower proportion of practicing female dermatologists in earlier years likely accounts for the lower percentage of females in dermatology citations and h-index top lists during that time, given that citation and h-index metrics are biased to dermatologists with longer careers.

Although our data are encouraging, females still accounted for less than one-third of the top 50 authors by publication numbers. Gender inequalities persist, with only one-third of a total of 1292 National Institutes of Health dermatology grants and one-fourth of Research Project Grant Program (R01) grants being awarded to females in the years 2009 to 2014.⁷ Therefore, formal and informal mentorship, protected time for research, resources for childcare, and opportunities for funding will be critical in supporting female dermatologists to both publish highly impactful research and obtain research grants.

Limitations of our study include the omission of authors with identical initials and the inability to account for name changes. Furthermore, Scopus does not include all articles published by each author. Finally, publication number reflects quantity but may not reflect quality.

By quantitating dermatology author publication numbers, we found better representation of female authors compared with studies measuring citation number and h-index. With higher proportions of female dermatology trainees and efforts to increase mentorship and research support for female dermatologists, we expect improved equality in top lists of dermatology citations and h-index values.

To the Editor:

Peer-reviewed publications are important determinants for promotions, academic leadership, and grants in dermatology.¹ The impact of the COVID-19 pandemic on dermatology research productivity remains an area of investigation. We sought to determine authorship trends for males and females during the pandemic.

A cross-sectional retrospective study of the top 20 dermatology journals—determined by impact factor and Google Scholar H5-index—was conducted to identify manuscripts with submission date specified prepandemic (May 1, 2019–October 31, 2019) and during the pandemic (May 1, 2020–October 31, 2020). Submission date, first/last author name, sex, and affiliated country were extracted. Single authors were designated as first authors. Gender API (https://gender-api.com/en/) classified gender. A χ² test (P<.05) compared differences in proportions of female first/last authors from 2019 to 2020.

Overall, 811 and 1061 articles submitted in 2019 and 2020, respectively, were included. There were 1517 articles submitted to clinical journals and 355 articles submitted to basic science journals (Table). For the 7 clinical journals included, there was a 7.7% decrease in the proportion of female last authors in 2020 vs 2019 (P=.002), with the largest decrease between August and September 2020. Although other comparisons did not yield statistically significant differences (P>.05 all)(Table), several trends were observed. For clinical journals, there was a 1.8% decrease in the proportion of female first authors. For the 4 basic science journals included, there was a 4.9% increase and a 0.3% decrease in percentages of female first and last authors, respectively, for 2020 vs 2019.

Our findings indicate that the COVID-19 pandemic may have impacted female authors’ productivity in clinical dermatology publications. In a survey-based study for 2010 to 2011, female physician-researchers (n=437) spent 8.5 more hours per week on domestic activities and childcare and were more likely to take time off for childcare if their partner worked full time compared with males (n=612)(42.6% vs 12.4%, respectively).² Our observation that female last authors had a significant decrease in publications may suggest that this population had a disproportionate burden of domestic labor and childcare during the pandemic. It is possible that last authors, who generally are more senior researchers, may be more likely to have childcare, eldercare, and other types of domestic responsibilities. Similarly, in a study of surgery submissions (n=1068), there were 6%, 7%, and 4% decreases in percentages of female last, corresponding, and first authors, respectively, from 2019 to 2020.³Our study had limitations. Only 11 journals were analyzed because others did not have specified submission dates. Some journals only provided submission information for a subset of articles (eg, those published in the In Press section), which may have accounted for the large discrepancy in submission numbers for 2019 to 2020. Gender could not be determined for 1% of authors and was limited to female and male. Although our study submission time frame (May–October 2020) aimed at identifying research conducted during the height of the COVID-19 pandemic, some of these studies may have been conducted months or years before the pandemic. Future studies should focus on longer and more comprehensive time frames. Finally, estimated dates of stay-at-home orders fail to consider differences within countries.

The proportion of female US-affiliated first and last authors publishing in dermatology journals increased from 12% to 48% in 1976 and from 6% to 31% in 2006,⁴ which is encouraging. However, a gender gap persists, with one-third of National Institutes of Health grants in dermatology and one-fourth of research project grants in dermatology awarded to women.⁵ Consequences of the pandemic on academic productivity may include fewer women represented in higher academic ranks, lower compensation, and lower career satisfaction compared with men.¹ We urge academic institutions and funding agencies to recognize and take action to mitigate long-term sequelae. Extended grant end dates and submission periods, funding opportunities dedicated to women, and prioritization of female-authored submissions are some strategies that can safeguard equitable career progression in dermatology research.

To the Editor:

Peer-reviewed publications are important determinants for promotions, academic leadership, and grants in dermatology.¹ The impact of the COVID-19 pandemic on dermatology research productivity remains an area of investigation. We sought to determine authorship trends for males and females during the pandemic.

A cross-sectional retrospective study of the top 20 dermatology journals—determined by impact factor and Google Scholar H5-index—was conducted to identify manuscripts with submission date specified prepandemic (May 1, 2019–October 31, 2019) and during the pandemic (May 1, 2020–October 31, 2020). Submission date, first/last author name, sex, and affiliated country were extracted. Single authors were designated as first authors. Gender API (https://gender-api.com/en/) classified gender. A χ² test (P<.05) compared differences in proportions of female first/last authors from 2019 to 2020.

Overall, 811 and 1061 articles submitted in 2019 and 2020, respectively, were included. There were 1517 articles submitted to clinical journals and 355 articles submitted to basic science journals (Table). For the 7 clinical journals included, there was a 7.7% decrease in the proportion of female last authors in 2020 vs 2019 (P=.002), with the largest decrease between August and September 2020. Although other comparisons did not yield statistically significant differences (P>.05 all)(Table), several trends were observed. For clinical journals, there was a 1.8% decrease in the proportion of female first authors. For the 4 basic science journals included, there was a 4.9% increase and a 0.3% decrease in percentages of female first and last authors, respectively, for 2020 vs 2019.

Our findings indicate that the COVID-19 pandemic may have impacted female authors’ productivity in clinical dermatology publications. In a survey-based study for 2010 to 2011, female physician-researchers (n=437) spent 8.5 more hours per week on domestic activities and childcare and were more likely to take time off for childcare if their partner worked full time compared with males (n=612)(42.6% vs 12.4%, respectively).² Our observation that female last authors had a significant decrease in publications may suggest that this population had a disproportionate burden of domestic labor and childcare during the pandemic. It is possible that last authors, who generally are more senior researchers, may be more likely to have childcare, eldercare, and other types of domestic responsibilities. Similarly, in a study of surgery submissions (n=1068), there were 6%, 7%, and 4% decreases in percentages of female last, corresponding, and first authors, respectively, from 2019 to 2020.³Our study had limitations. Only 11 journals were analyzed because others did not have specified submission dates. Some journals only provided submission information for a subset of articles (eg, those published in the In Press section), which may have accounted for the large discrepancy in submission numbers for 2019 to 2020. Gender could not be determined for 1% of authors and was limited to female and male. Although our study submission time frame (May–October 2020) aimed at identifying research conducted during the height of the COVID-19 pandemic, some of these studies may have been conducted months or years before the pandemic. Future studies should focus on longer and more comprehensive time frames. Finally, estimated dates of stay-at-home orders fail to consider differences within countries.

The proportion of female US-affiliated first and last authors publishing in dermatology journals increased from 12% to 48% in 1976 and from 6% to 31% in 2006,⁴ which is encouraging. However, a gender gap persists, with one-third of National Institutes of Health grants in dermatology and one-fourth of research project grants in dermatology awarded to women.⁵ Consequences of the pandemic on academic productivity may include fewer women represented in higher academic ranks, lower compensation, and lower career satisfaction compared with men.¹ We urge academic institutions and funding agencies to recognize and take action to mitigate long-term sequelae. Extended grant end dates and submission periods, funding opportunities dedicated to women, and prioritization of female-authored submissions are some strategies that can safeguard equitable career progression in dermatology research.

To the Editor:

Peer-reviewed publications are important determinants for promotions, academic leadership, and grants in dermatology.¹ The impact of the COVID-19 pandemic on dermatology research productivity remains an area of investigation. We sought to determine authorship trends for males and females during the pandemic.

A cross-sectional retrospective study of the top 20 dermatology journals—determined by impact factor and Google Scholar H5-index—was conducted to identify manuscripts with submission date specified prepandemic (May 1, 2019–October 31, 2019) and during the pandemic (May 1, 2020–October 31, 2020). Submission date, first/last author name, sex, and affiliated country were extracted. Single authors were designated as first authors. Gender API (https://gender-api.com/en/) classified gender. A χ² test (P<.05) compared differences in proportions of female first/last authors from 2019 to 2020.

Overall, 811 and 1061 articles submitted in 2019 and 2020, respectively, were included. There were 1517 articles submitted to clinical journals and 355 articles submitted to basic science journals (Table). For the 7 clinical journals included, there was a 7.7% decrease in the proportion of female last authors in 2020 vs 2019 (P=.002), with the largest decrease between August and September 2020. Although other comparisons did not yield statistically significant differences (P>.05 all)(Table), several trends were observed. For clinical journals, there was a 1.8% decrease in the proportion of female first authors. For the 4 basic science journals included, there was a 4.9% increase and a 0.3% decrease in percentages of female first and last authors, respectively, for 2020 vs 2019.

Our findings indicate that the COVID-19 pandemic may have impacted female authors’ productivity in clinical dermatology publications. In a survey-based study for 2010 to 2011, female physician-researchers (n=437) spent 8.5 more hours per week on domestic activities and childcare and were more likely to take time off for childcare if their partner worked full time compared with males (n=612)(42.6% vs 12.4%, respectively).² Our observation that female last authors had a significant decrease in publications may suggest that this population had a disproportionate burden of domestic labor and childcare during the pandemic. It is possible that last authors, who generally are more senior researchers, may be more likely to have childcare, eldercare, and other types of domestic responsibilities. Similarly, in a study of surgery submissions (n=1068), there were 6%, 7%, and 4% decreases in percentages of female last, corresponding, and first authors, respectively, from 2019 to 2020.³Our study had limitations. Only 11 journals were analyzed because others did not have specified submission dates. Some journals only provided submission information for a subset of articles (eg, those published in the In Press section), which may have accounted for the large discrepancy in submission numbers for 2019 to 2020. Gender could not be determined for 1% of authors and was limited to female and male. Although our study submission time frame (May–October 2020) aimed at identifying research conducted during the height of the COVID-19 pandemic, some of these studies may have been conducted months or years before the pandemic. Future studies should focus on longer and more comprehensive time frames. Finally, estimated dates of stay-at-home orders fail to consider differences within countries.

The proportion of female US-affiliated first and last authors publishing in dermatology journals increased from 12% to 48% in 1976 and from 6% to 31% in 2006,⁴ which is encouraging. However, a gender gap persists, with one-third of National Institutes of Health grants in dermatology and one-fourth of research project grants in dermatology awarded to women.⁵ Consequences of the pandemic on academic productivity may include fewer women represented in higher academic ranks, lower compensation, and lower career satisfaction compared with men.¹ We urge academic institutions and funding agencies to recognize and take action to mitigate long-term sequelae. Extended grant end dates and submission periods, funding opportunities dedicated to women, and prioritization of female-authored submissions are some strategies that can safeguard equitable career progression in dermatology research.

To the Editor:

Dermatology is one of the most competitive residencies for matching, with a 57.5% match rate in 2022.¹ Our prior study of research-mentor relationships among matched dermatology applicants corroborated the importance of home programs (HPs) and program connections.² Therefore, our current objective was to compare profiles of matched dermatology applicants without HPs vs those with HPs.

We searched websites of 139 dermatology programs nationwide and found 1736 matched applicants from 2016 to 2020; of them, 323 did not have HPs. We determined program rank by research output using Doximity Residency Navigator (https://www.doximity.com/residency/). Advanced degrees (ADs) of applicants were identified using program websites and LinkedIn. A PubMed search was conducted for number of articles published by each applicant before September 15 of their match year. For applicants without HPs, we identified the senior author on each publication. The senior author publishing with an applicant most often was considered the research mentor. Two-tailed independent t tests and χ² tests were used to determine statistical significance (P<.05).

On average, matched applicants without HPs matched in lower-ranked (74.4) and smaller (12.4) programs compared with matched applicants with HPs (45.3 [P<.0001] and 15.1 [P<.0001], respectively)(eTable). The mean number of publications was similar between matched applicants with HPs and without HPs (5.64 and 4.80, respectively; P=.0525) as well as the percentage with ADs (14.7% and 11.5%, respectively; P=.0953). Overall, 14.8% of matched applicants without HPs matched at their mentors’ institutions.

Data were obtained for matched international applicants as a subset of non-HP applicants. Despite attending medical schools without associated HPs in the United States, international applicants matched at similarly ranked (44.3) and sized (15.0) programs, on average, compared with HP applicants. The mean number of publications was higher for international applicants (11.4) vs domestic applicants (5.33). International applicants more often had ADs (23.8%) and 60.1% of them held doctor of philosophy degrees. Overall, 40.5% of international applicants matched at their mentors’ institutions.

Our study suggests that matched dermatology applicants with and without HPs had similar achievements, on average, for the number of publications and percentage with ADs. However, non-HP applicants matched at lower-ranked programs than HP applicants. Therefore, applicants without HPs should strongly consider cultivating program connections, especially if they desire to match at higher-ranked dermatology programs. To illustrate, the rate of matching at research mentors’ institutions was approximately 3-times higher for international applicants than non-HP applicants overall. Despite the disadvantages of applying as international applicants, they were able to match at substantially higher-ranked dermatology programs than non-HP applicants. International applicants may have a longer time investment—the number of years from obtaining their medical degree or US medical license to matching—giving them time to produce quality research and develop meaningful relationships at an institution. Additionally, our prior study of the top 25 dermatology residencies showed that 26.2% of successful applicants matched at their research mentors’ institutions, with almost half of this subset matching at their HPs, where their mentors also practiced.² Because of the potential benefits of having program connections, applicants without HPs should seek dermatology research mentors, especially via highly beneficial in-person networking opportunities (eg, away rotations, conferences) that had previously been limited during the COVID-19 pandemic.³ Formal mentorship programs giving priority to students without HPs recently have been developed, which only begins to address the inequities in the dermatology residency application process.⁴

Study limitations include lack of resident information on 15 program websites, missed publications due to applicant name changes, not accounting for abstracts and posters, and inability to collect data on unmatched applicants.

We hope that our study alleviates some concerns that applicants without HPs may have regarding applying for dermatology residency and encourages those with a genuine interest in dermatology to pursue the specialty, provided they find a strong research mentor. Residency programs should be cognizant of the unique challenges that non-HP applicants face for matching.

To the Editor:

Dermatology is one of the most competitive residencies for matching, with a 57.5% match rate in 2022.¹ Our prior study of research-mentor relationships among matched dermatology applicants corroborated the importance of home programs (HPs) and program connections.² Therefore, our current objective was to compare profiles of matched dermatology applicants without HPs vs those with HPs.

We searched websites of 139 dermatology programs nationwide and found 1736 matched applicants from 2016 to 2020; of them, 323 did not have HPs. We determined program rank by research output using Doximity Residency Navigator (https://www.doximity.com/residency/). Advanced degrees (ADs) of applicants were identified using program websites and LinkedIn. A PubMed search was conducted for number of articles published by each applicant before September 15 of their match year. For applicants without HPs, we identified the senior author on each publication. The senior author publishing with an applicant most often was considered the research mentor. Two-tailed independent t tests and χ² tests were used to determine statistical significance (P<.05).

On average, matched applicants without HPs matched in lower-ranked (74.4) and smaller (12.4) programs compared with matched applicants with HPs (45.3 [P<.0001] and 15.1 [P<.0001], respectively)(eTable). The mean number of publications was similar between matched applicants with HPs and without HPs (5.64 and 4.80, respectively; P=.0525) as well as the percentage with ADs (14.7% and 11.5%, respectively; P=.0953). Overall, 14.8% of matched applicants without HPs matched at their mentors’ institutions.

Data were obtained for matched international applicants as a subset of non-HP applicants. Despite attending medical schools without associated HPs in the United States, international applicants matched at similarly ranked (44.3) and sized (15.0) programs, on average, compared with HP applicants. The mean number of publications was higher for international applicants (11.4) vs domestic applicants (5.33). International applicants more often had ADs (23.8%) and 60.1% of them held doctor of philosophy degrees. Overall, 40.5% of international applicants matched at their mentors’ institutions.

Our study suggests that matched dermatology applicants with and without HPs had similar achievements, on average, for the number of publications and percentage with ADs. However, non-HP applicants matched at lower-ranked programs than HP applicants. Therefore, applicants without HPs should strongly consider cultivating program connections, especially if they desire to match at higher-ranked dermatology programs. To illustrate, the rate of matching at research mentors’ institutions was approximately 3-times higher for international applicants than non-HP applicants overall. Despite the disadvantages of applying as international applicants, they were able to match at substantially higher-ranked dermatology programs than non-HP applicants. International applicants may have a longer time investment—the number of years from obtaining their medical degree or US medical license to matching—giving them time to produce quality research and develop meaningful relationships at an institution. Additionally, our prior study of the top 25 dermatology residencies showed that 26.2% of successful applicants matched at their research mentors’ institutions, with almost half of this subset matching at their HPs, where their mentors also practiced.² Because of the potential benefits of having program connections, applicants without HPs should seek dermatology research mentors, especially via highly beneficial in-person networking opportunities (eg, away rotations, conferences) that had previously been limited during the COVID-19 pandemic.³ Formal mentorship programs giving priority to students without HPs recently have been developed, which only begins to address the inequities in the dermatology residency application process.⁴

Study limitations include lack of resident information on 15 program websites, missed publications due to applicant name changes, not accounting for abstracts and posters, and inability to collect data on unmatched applicants.

We hope that our study alleviates some concerns that applicants without HPs may have regarding applying for dermatology residency and encourages those with a genuine interest in dermatology to pursue the specialty, provided they find a strong research mentor. Residency programs should be cognizant of the unique challenges that non-HP applicants face for matching.

To the Editor:

Dermatology is one of the most competitive residencies for matching, with a 57.5% match rate in 2022.¹ Our prior study of research-mentor relationships among matched dermatology applicants corroborated the importance of home programs (HPs) and program connections.² Therefore, our current objective was to compare profiles of matched dermatology applicants without HPs vs those with HPs.

We searched websites of 139 dermatology programs nationwide and found 1736 matched applicants from 2016 to 2020; of them, 323 did not have HPs. We determined program rank by research output using Doximity Residency Navigator (https://www.doximity.com/residency/). Advanced degrees (ADs) of applicants were identified using program websites and LinkedIn. A PubMed search was conducted for number of articles published by each applicant before September 15 of their match year. For applicants without HPs, we identified the senior author on each publication. The senior author publishing with an applicant most often was considered the research mentor. Two-tailed independent t tests and χ² tests were used to determine statistical significance (P<.05).

On average, matched applicants without HPs matched in lower-ranked (74.4) and smaller (12.4) programs compared with matched applicants with HPs (45.3 [P<.0001] and 15.1 [P<.0001], respectively)(eTable). The mean number of publications was similar between matched applicants with HPs and without HPs (5.64 and 4.80, respectively; P=.0525) as well as the percentage with ADs (14.7% and 11.5%, respectively; P=.0953). Overall, 14.8% of matched applicants without HPs matched at their mentors’ institutions.

Data were obtained for matched international applicants as a subset of non-HP applicants. Despite attending medical schools without associated HPs in the United States, international applicants matched at similarly ranked (44.3) and sized (15.0) programs, on average, compared with HP applicants. The mean number of publications was higher for international applicants (11.4) vs domestic applicants (5.33). International applicants more often had ADs (23.8%) and 60.1% of them held doctor of philosophy degrees. Overall, 40.5% of international applicants matched at their mentors’ institutions.

Our study suggests that matched dermatology applicants with and without HPs had similar achievements, on average, for the number of publications and percentage with ADs. However, non-HP applicants matched at lower-ranked programs than HP applicants. Therefore, applicants without HPs should strongly consider cultivating program connections, especially if they desire to match at higher-ranked dermatology programs. To illustrate, the rate of matching at research mentors’ institutions was approximately 3-times higher for international applicants than non-HP applicants overall. Despite the disadvantages of applying as international applicants, they were able to match at substantially higher-ranked dermatology programs than non-HP applicants. International applicants may have a longer time investment—the number of years from obtaining their medical degree or US medical license to matching—giving them time to produce quality research and develop meaningful relationships at an institution. Additionally, our prior study of the top 25 dermatology residencies showed that 26.2% of successful applicants matched at their research mentors’ institutions, with almost half of this subset matching at their HPs, where their mentors also practiced.² Because of the potential benefits of having program connections, applicants without HPs should seek dermatology research mentors, especially via highly beneficial in-person networking opportunities (eg, away rotations, conferences) that had previously been limited during the COVID-19 pandemic.³ Formal mentorship programs giving priority to students without HPs recently have been developed, which only begins to address the inequities in the dermatology residency application process.⁴

Study limitations include lack of resident information on 15 program websites, missed publications due to applicant name changes, not accounting for abstracts and posters, and inability to collect data on unmatched applicants.

We hope that our study alleviates some concerns that applicants without HPs may have regarding applying for dermatology residency and encourages those with a genuine interest in dermatology to pursue the specialty, provided they find a strong research mentor. Residency programs should be cognizant of the unique challenges that non-HP applicants face for matching.

Practice Gap

Nail matrix and nail bed injections with triamcinolone acetonide are used to treat trachyonychia and inflammatory nail conditions, including nail psoriasis and nail lichen planus. The procedure should be quick in well-trained hands, with each nail injection taking only seconds to perform. Typically, patients have multiple nails involved, requiring at least 1 injection into the nail matrix or the nail bed (or both) in each nail at each visit. Patients often are anxious when undergoing nail injections; the nail unit is highly innervated and vascular, which can cause notable transient discomfort during the procedure^1,2 as well as postoperative pain.³

Nail injections must be repeated every 4 to 6 weeks to sustain clinical benefit and maximize outcomes, which can lead to heightened anxiety and apprehension before and during the visit. Furthermore, pain and anxiety associated with the procedure may deter patients from returning for follow-up injections, which can impact treatment adherence and clinical outcomes.

Dermatologists should implement strategies to decrease periprocedural anxiety to improve the nail injection experience. In our practice, we routinely incorporate stress-reducing techniques—music, talkesthesia, a sleep mask, cool air, ethyl chloride, and squeezing a stress ball—into the clinical workflow of the procedure. The goal of these techniques is to divert attention away from painful stimuli. Most patients, however, receive injections in both hands, making it impractical to employ some of these techniques, particularly squeezing a stress ball. We employed a unique method involving polyurethane tubing to reduce stress and anxiety during nail procedures.

The Technique

A patient was receiving treatment with intralesional triamcinolone injections to the nail matrix for trachyonychia involving all of the fingernails. He worked as an equipment and facilities manager, giving him access to polyurethane tubing, which is routinely used in the manufacture of some medical devices that require gas or liquid to operate. He found the nail injections to be painful but was motivated to proceed with treatment. He brought in a piece of polyurethane tubing to a subsequent visit to bite on during the injections (Figure) and reported considerable relief of pain.

What you were not taught in United States history class was that this method—clenching an object orally—dates to the era before the Civil War, before appropriate anesthetics and analgesics were developed, when patients and soldiers bit on a bullet or leather strap during surgical procedures.⁴ Clenching and chewing have been shown to promote relaxation and reduce acute pain and stress.⁵

Practical Implications

Polyurethane tubing can be purchased in bulk, is inexpensive ($0.30/foot on Amazon), and unlikely to damage teeth due to its flexibility. It can be cut into 6-inch pieces and given to the patient at their first nail injection appointment. The patient can then bring the tubing to subsequent appointments to use as a mastication tool during nail injections.

We instruct the patient to disinfect the dedicated piece of tubing after the initial visit and each subsequent visit by soaking it for 15 minutes in either a 3% hydrogen peroxide solution, antibacterial mouthwash, a solution of baking soda (bicarbonate of soda) and water (1 cup of water to 2 teaspoons of baking soda), or white vinegar. We instruct them to thoroughly dry the disinfected polyurethane tube and store it in a clean, reusable, resealable zipper storage bag between appointments.

In addition to reducing anxiety and pain, this method also distracts the patient and therefore promotes patient and physician safety. Patients are less likely to jump or startle during the injection, thereby reducing the risk of physically interfering with the nail surgeon or making an unanticipated advance into the surgical field.

Although frustrated patients with nail disease may need to “bite the bullet” when they accept treatment with nail injections, lessons from our patient and from United States history offer a safe and cost-effective pain management strategy. Minimizing discomfort and anxiety during the first nail injection is crucial because doing so is likely to promote adherence with follow-up injections and therefore improve clinical outcomes.

Future clinical studies should validate the clinical utility of oral mastication and clenching during nail procedures compared to other perioperative stress- and anxiety-reducing techniques.

Practice Gap

Nail matrix and nail bed injections with triamcinolone acetonide are used to treat trachyonychia and inflammatory nail conditions, including nail psoriasis and nail lichen planus. The procedure should be quick in well-trained hands, with each nail injection taking only seconds to perform. Typically, patients have multiple nails involved, requiring at least 1 injection into the nail matrix or the nail bed (or both) in each nail at each visit. Patients often are anxious when undergoing nail injections; the nail unit is highly innervated and vascular, which can cause notable transient discomfort during the procedure^1,2 as well as postoperative pain.³

Nail injections must be repeated every 4 to 6 weeks to sustain clinical benefit and maximize outcomes, which can lead to heightened anxiety and apprehension before and during the visit. Furthermore, pain and anxiety associated with the procedure may deter patients from returning for follow-up injections, which can impact treatment adherence and clinical outcomes.

Dermatologists should implement strategies to decrease periprocedural anxiety to improve the nail injection experience. In our practice, we routinely incorporate stress-reducing techniques—music, talkesthesia, a sleep mask, cool air, ethyl chloride, and squeezing a stress ball—into the clinical workflow of the procedure. The goal of these techniques is to divert attention away from painful stimuli. Most patients, however, receive injections in both hands, making it impractical to employ some of these techniques, particularly squeezing a stress ball. We employed a unique method involving polyurethane tubing to reduce stress and anxiety during nail procedures.

The Technique

A patient was receiving treatment with intralesional triamcinolone injections to the nail matrix for trachyonychia involving all of the fingernails. He worked as an equipment and facilities manager, giving him access to polyurethane tubing, which is routinely used in the manufacture of some medical devices that require gas or liquid to operate. He found the nail injections to be painful but was motivated to proceed with treatment. He brought in a piece of polyurethane tubing to a subsequent visit to bite on during the injections (Figure) and reported considerable relief of pain.

What you were not taught in United States history class was that this method—clenching an object orally—dates to the era before the Civil War, before appropriate anesthetics and analgesics were developed, when patients and soldiers bit on a bullet or leather strap during surgical procedures.⁴ Clenching and chewing have been shown to promote relaxation and reduce acute pain and stress.⁵

Practical Implications

Polyurethane tubing can be purchased in bulk, is inexpensive ($0.30/foot on Amazon), and unlikely to damage teeth due to its flexibility. It can be cut into 6-inch pieces and given to the patient at their first nail injection appointment. The patient can then bring the tubing to subsequent appointments to use as a mastication tool during nail injections.

We instruct the patient to disinfect the dedicated piece of tubing after the initial visit and each subsequent visit by soaking it for 15 minutes in either a 3% hydrogen peroxide solution, antibacterial mouthwash, a solution of baking soda (bicarbonate of soda) and water (1 cup of water to 2 teaspoons of baking soda), or white vinegar. We instruct them to thoroughly dry the disinfected polyurethane tube and store it in a clean, reusable, resealable zipper storage bag between appointments.

In addition to reducing anxiety and pain, this method also distracts the patient and therefore promotes patient and physician safety. Patients are less likely to jump or startle during the injection, thereby reducing the risk of physically interfering with the nail surgeon or making an unanticipated advance into the surgical field.

Although frustrated patients with nail disease may need to “bite the bullet” when they accept treatment with nail injections, lessons from our patient and from United States history offer a safe and cost-effective pain management strategy. Minimizing discomfort and anxiety during the first nail injection is crucial because doing so is likely to promote adherence with follow-up injections and therefore improve clinical outcomes.

Future clinical studies should validate the clinical utility of oral mastication and clenching during nail procedures compared to other perioperative stress- and anxiety-reducing techniques.

Practice Gap

Nail matrix and nail bed injections with triamcinolone acetonide are used to treat trachyonychia and inflammatory nail conditions, including nail psoriasis and nail lichen planus. The procedure should be quick in well-trained hands, with each nail injection taking only seconds to perform. Typically, patients have multiple nails involved, requiring at least 1 injection into the nail matrix or the nail bed (or both) in each nail at each visit. Patients often are anxious when undergoing nail injections; the nail unit is highly innervated and vascular, which can cause notable transient discomfort during the procedure^1,2 as well as postoperative pain.³

Nail injections must be repeated every 4 to 6 weeks to sustain clinical benefit and maximize outcomes, which can lead to heightened anxiety and apprehension before and during the visit. Furthermore, pain and anxiety associated with the procedure may deter patients from returning for follow-up injections, which can impact treatment adherence and clinical outcomes.

Dermatologists should implement strategies to decrease periprocedural anxiety to improve the nail injection experience. In our practice, we routinely incorporate stress-reducing techniques—music, talkesthesia, a sleep mask, cool air, ethyl chloride, and squeezing a stress ball—into the clinical workflow of the procedure. The goal of these techniques is to divert attention away from painful stimuli. Most patients, however, receive injections in both hands, making it impractical to employ some of these techniques, particularly squeezing a stress ball. We employed a unique method involving polyurethane tubing to reduce stress and anxiety during nail procedures.

The Technique

A patient was receiving treatment with intralesional triamcinolone injections to the nail matrix for trachyonychia involving all of the fingernails. He worked as an equipment and facilities manager, giving him access to polyurethane tubing, which is routinely used in the manufacture of some medical devices that require gas or liquid to operate. He found the nail injections to be painful but was motivated to proceed with treatment. He brought in a piece of polyurethane tubing to a subsequent visit to bite on during the injections (Figure) and reported considerable relief of pain.

What you were not taught in United States history class was that this method—clenching an object orally—dates to the era before the Civil War, before appropriate anesthetics and analgesics were developed, when patients and soldiers bit on a bullet or leather strap during surgical procedures.⁴ Clenching and chewing have been shown to promote relaxation and reduce acute pain and stress.⁵

Practical Implications

Polyurethane tubing can be purchased in bulk, is inexpensive ($0.30/foot on Amazon), and unlikely to damage teeth due to its flexibility. It can be cut into 6-inch pieces and given to the patient at their first nail injection appointment. The patient can then bring the tubing to subsequent appointments to use as a mastication tool during nail injections.

We instruct the patient to disinfect the dedicated piece of tubing after the initial visit and each subsequent visit by soaking it for 15 minutes in either a 3% hydrogen peroxide solution, antibacterial mouthwash, a solution of baking soda (bicarbonate of soda) and water (1 cup of water to 2 teaspoons of baking soda), or white vinegar. We instruct them to thoroughly dry the disinfected polyurethane tube and store it in a clean, reusable, resealable zipper storage bag between appointments.

In addition to reducing anxiety and pain, this method also distracts the patient and therefore promotes patient and physician safety. Patients are less likely to jump or startle during the injection, thereby reducing the risk of physically interfering with the nail surgeon or making an unanticipated advance into the surgical field.

Although frustrated patients with nail disease may need to “bite the bullet” when they accept treatment with nail injections, lessons from our patient and from United States history offer a safe and cost-effective pain management strategy. Minimizing discomfort and anxiety during the first nail injection is crucial because doing so is likely to promote adherence with follow-up injections and therefore improve clinical outcomes.

Future clinical studies should validate the clinical utility of oral mastication and clenching during nail procedures compared to other perioperative stress- and anxiety-reducing techniques.

Practice Gap

Terbinafine can be used safely and effectively in adult and pediatric patients to treat superficial fungal infections, including onychomycosis.¹ These superficial fungal infections have become increasingly prevalent in children and often require oral therapy²; however, children are frequently unable to swallow a pill.

Until 2016, terbinafine was available as oral granules that could be sprinkled on food, but this formulation has been discontinued.³ In addition, terbinafine tablets have a bitter taste. Therefore, the inability to swallow a pill—typical of young children and other patients with pill dysphagia—is a barrier to prescribing terbinafine.

The Technique

For patients who cannot swallow a pill, a terbinafine tablet can be crushed and mixed with food or a syrup without loss of efficacy. Terbinafine in tablet form has been shown to have relatively unchanged properties after being crushed and mixed in solution, even several weeks after preparation.⁴ Crushing and mixing a terbinafine tablet with food or a syrup therefore is an effective option for patients who cannot swallow a pill but can safely swallow food.

The food or syrup used for this purpose should have a pH of at least 5 because greater acidity reduces absorption of terbinafine. Therefore, avoid mixing it with fruit juices, applesauce, or soda. Given the bitter taste of the terbinafine tablet, mixing it with a sweet food or syrup improves taste and compliance, which makes pudding a particularly good food option for this purpose.

However, because younger patients might not finish an entire serving of pudding or other food into which the tablet has been crushed and mixed, inconsistent dosing might result. Therefore, we recommend mixing the crushed terbinafine tablet with 1 oz (30 mL) of chocolate syrup or corn syrup (Figure). This solution is sweet, easy to prepare and consume, widely available, and affordable (as low as $0.28/oz for corn syrup and as low as $0.10/oz for chocolate syrup, as priced on Amazon).

The tablet can be crushed using a pill crusher ($5–$10 at pharmacies or on Amazon) or by placing it on a piece of paper and crushing it with the back of a metal spoon. For children, the recommended dosing of terbinafine with a 250-mg tablet is based on weight: one-quarter of a tablet for a child weighing 10 to 20 kg; one-half of a tablet for a child weighing 20 to 40 kg; and a full tablet for a child weighing more than 40 kg.⁵ Because terbinafine tablets are not scored, a combined pill splitter–crusher can be used (also available at pharmacies or on Amazon; the price of this device is within the same price range as a pill crusher).

Practical Implication

Use of this method for crushing and mixing the terbinafine tablet allows patients who are unable to swallow a pill to safely and effectively use oral terbinafine.

Practice Gap

Terbinafine can be used safely and effectively in adult and pediatric patients to treat superficial fungal infections, including onychomycosis.¹ These superficial fungal infections have become increasingly prevalent in children and often require oral therapy²; however, children are frequently unable to swallow a pill.

Until 2016, terbinafine was available as oral granules that could be sprinkled on food, but this formulation has been discontinued.³ In addition, terbinafine tablets have a bitter taste. Therefore, the inability to swallow a pill—typical of young children and other patients with pill dysphagia—is a barrier to prescribing terbinafine.

The Technique

For patients who cannot swallow a pill, a terbinafine tablet can be crushed and mixed with food or a syrup without loss of efficacy. Terbinafine in tablet form has been shown to have relatively unchanged properties after being crushed and mixed in solution, even several weeks after preparation.⁴ Crushing and mixing a terbinafine tablet with food or a syrup therefore is an effective option for patients who cannot swallow a pill but can safely swallow food.

The food or syrup used for this purpose should have a pH of at least 5 because greater acidity reduces absorption of terbinafine. Therefore, avoid mixing it with fruit juices, applesauce, or soda. Given the bitter taste of the terbinafine tablet, mixing it with a sweet food or syrup improves taste and compliance, which makes pudding a particularly good food option for this purpose.

However, because younger patients might not finish an entire serving of pudding or other food into which the tablet has been crushed and mixed, inconsistent dosing might result. Therefore, we recommend mixing the crushed terbinafine tablet with 1 oz (30 mL) of chocolate syrup or corn syrup (Figure). This solution is sweet, easy to prepare and consume, widely available, and affordable (as low as $0.28/oz for corn syrup and as low as $0.10/oz for chocolate syrup, as priced on Amazon).

The tablet can be crushed using a pill crusher ($5–$10 at pharmacies or on Amazon) or by placing it on a piece of paper and crushing it with the back of a metal spoon. For children, the recommended dosing of terbinafine with a 250-mg tablet is based on weight: one-quarter of a tablet for a child weighing 10 to 20 kg; one-half of a tablet for a child weighing 20 to 40 kg; and a full tablet for a child weighing more than 40 kg.⁵ Because terbinafine tablets are not scored, a combined pill splitter–crusher can be used (also available at pharmacies or on Amazon; the price of this device is within the same price range as a pill crusher).

Practical Implication

Use of this method for crushing and mixing the terbinafine tablet allows patients who are unable to swallow a pill to safely and effectively use oral terbinafine.

Practice Gap

Terbinafine can be used safely and effectively in adult and pediatric patients to treat superficial fungal infections, including onychomycosis.¹ These superficial fungal infections have become increasingly prevalent in children and often require oral therapy²; however, children are frequently unable to swallow a pill.

Until 2016, terbinafine was available as oral granules that could be sprinkled on food, but this formulation has been discontinued.³ In addition, terbinafine tablets have a bitter taste. Therefore, the inability to swallow a pill—typical of young children and other patients with pill dysphagia—is a barrier to prescribing terbinafine.

The Technique

For patients who cannot swallow a pill, a terbinafine tablet can be crushed and mixed with food or a syrup without loss of efficacy. Terbinafine in tablet form has been shown to have relatively unchanged properties after being crushed and mixed in solution, even several weeks after preparation.⁴ Crushing and mixing a terbinafine tablet with food or a syrup therefore is an effective option for patients who cannot swallow a pill but can safely swallow food.

The food or syrup used for this purpose should have a pH of at least 5 because greater acidity reduces absorption of terbinafine. Therefore, avoid mixing it with fruit juices, applesauce, or soda. Given the bitter taste of the terbinafine tablet, mixing it with a sweet food or syrup improves taste and compliance, which makes pudding a particularly good food option for this purpose.

However, because younger patients might not finish an entire serving of pudding or other food into which the tablet has been crushed and mixed, inconsistent dosing might result. Therefore, we recommend mixing the crushed terbinafine tablet with 1 oz (30 mL) of chocolate syrup or corn syrup (Figure). This solution is sweet, easy to prepare and consume, widely available, and affordable (as low as $0.28/oz for corn syrup and as low as $0.10/oz for chocolate syrup, as priced on Amazon).

The tablet can be crushed using a pill crusher ($5–$10 at pharmacies or on Amazon) or by placing it on a piece of paper and crushing it with the back of a metal spoon. For children, the recommended dosing of terbinafine with a 250-mg tablet is based on weight: one-quarter of a tablet for a child weighing 10 to 20 kg; one-half of a tablet for a child weighing 20 to 40 kg; and a full tablet for a child weighing more than 40 kg.⁵ Because terbinafine tablets are not scored, a combined pill splitter–crusher can be used (also available at pharmacies or on Amazon; the price of this device is within the same price range as a pill crusher).

Practical Implication

Use of this method for crushing and mixing the terbinafine tablet allows patients who are unable to swallow a pill to safely and effectively use oral terbinafine.

To the Editor:

Preprint servers allow researchers to post manuscripts before publication in peer-reviewed journals. As of January 2022, 41 public preprint servers accepted medicine/science submissions.¹ We sought to analyze characteristics of dermatology manuscripts in preprint servers and assess preprint publication policies in top dermatology journals.

Thirty-five biology/health sciences preprint servers¹ were searched (March 3 to March 24, 2021) with keywords dermatology, skin, and cutaneous. Preprint server, preprint post date, location, metrics, journal, impact factor (IF), and journal publication date were recorded. Preprint policies of the top 20 dermatology journals—determined by impact factor of the journal (https://www.scimagojr.com/)—were reviewed. Two-tailed t tests and χ² tests were performed (P<.05).

A total of 1420 articles were posted to 11 preprint servers between June 20, 2007, and February 15, 2021 (Table 1); 377 (27%) were published in peer-reviewed journals, with 350 (93%) of those published within 1 year of preprint post. Preprints were published in 203 journals with a mean IF of 6.2. Growth in preprint posts by year (2007-2020) was exponential (R²=0.78)(Figure). On average, preprints were viewed 424 times (Table 2), with published preprints viewed more often than unpublished preprints (596 vs 362 views)(P<.001). Only 23 of 786 (3%) preprints with comments enabled had feedback. Among the top 20 dermatology journals, 18 (90%) allowed preprints, 1 (5%) evaluated case by case, and 1 (5%) prohibited preprints.

Our study showed exponential growth in dermatology preprints, a low proportion published in peer-reviewed journals with high IFs, and a substantial number of page views for both published and unpublished preprints. Very few preprints had feedback. We found that most of the top 20 dermatology journals accept preprints. An analysis of 61 dermatology articles in medRxiv found only 51% (31/61) of articles were subsequently published.² The low rate of publication may be due to the quality of preprints that do not meet criteria to be published following peer review.

Preprint servers are fairly novel, with a majority launched within the last 5 years.¹ The goal of preprints is to claim conception of an idea, solicit feedback prior to submission for peer review, and expedite research distribution.³ Because preprints are uploaded without peer review, manuscripts may lack quality and accuracy. An analysis of 57 of thelargest preprint servers found that few provided guidelines on authorship, image manipulation, or reporting of study limitations; however, most preprint servers do perform some screening.⁴ medRxiv requires full scientific research reports and absence of obscenity, plagiarism, and patient identifiers. In its first year, medRxiv rejected 34% of 176 submissios; reasons were not disclosed.⁵

The low rate of on-site comments suggests that preprint servers may not be effective for obtaining feedback to improve dermatology manuscripts prior to journal submission. Almost all of the top 20 dermatologyjournals accept preprints. Therefore, dermatologists may use these preprint servers to assert project ideas and disseminate research quickly and freely but may not receive constructive criticism.

Our study is subject to several limitations. Although our search was extensive, it is possible manuscripts were missed. Article metrics also were not available on all servers, and we could not account for accepted articles that were not yet indexed.

There has been a surge in posting of dermatology preprints in recent years. Preprints have not been peer reviewed, and data should be corroborated before incorporating new diagnostics or treatments into clinical practice. Utilization of preprint servers by dermatologists is increasing, but because the impact is still unknown, further studies on accuracy and reliability of preprints are warranted.

To the Editor:

Preprint servers allow researchers to post manuscripts before publication in peer-reviewed journals. As of January 2022, 41 public preprint servers accepted medicine/science submissions.¹ We sought to analyze characteristics of dermatology manuscripts in preprint servers and assess preprint publication policies in top dermatology journals.

Thirty-five biology/health sciences preprint servers¹ were searched (March 3 to March 24, 2021) with keywords dermatology, skin, and cutaneous. Preprint server, preprint post date, location, metrics, journal, impact factor (IF), and journal publication date were recorded. Preprint policies of the top 20 dermatology journals—determined by impact factor of the journal (https://www.scimagojr.com/)—were reviewed. Two-tailed t tests and χ² tests were performed (P<.05).

A total of 1420 articles were posted to 11 preprint servers between June 20, 2007, and February 15, 2021 (Table 1); 377 (27%) were published in peer-reviewed journals, with 350 (93%) of those published within 1 year of preprint post. Preprints were published in 203 journals with a mean IF of 6.2. Growth in preprint posts by year (2007-2020) was exponential (R²=0.78)(Figure). On average, preprints were viewed 424 times (Table 2), with published preprints viewed more often than unpublished preprints (596 vs 362 views)(P<.001). Only 23 of 786 (3%) preprints with comments enabled had feedback. Among the top 20 dermatology journals, 18 (90%) allowed preprints, 1 (5%) evaluated case by case, and 1 (5%) prohibited preprints.

Our study showed exponential growth in dermatology preprints, a low proportion published in peer-reviewed journals with high IFs, and a substantial number of page views for both published and unpublished preprints. Very few preprints had feedback. We found that most of the top 20 dermatology journals accept preprints. An analysis of 61 dermatology articles in medRxiv found only 51% (31/61) of articles were subsequently published.² The low rate of publication may be due to the quality of preprints that do not meet criteria to be published following peer review.

Preprint servers are fairly novel, with a majority launched within the last 5 years.¹ The goal of preprints is to claim conception of an idea, solicit feedback prior to submission for peer review, and expedite research distribution.³ Because preprints are uploaded without peer review, manuscripts may lack quality and accuracy. An analysis of 57 of thelargest preprint servers found that few provided guidelines on authorship, image manipulation, or reporting of study limitations; however, most preprint servers do perform some screening.⁴ medRxiv requires full scientific research reports and absence of obscenity, plagiarism, and patient identifiers. In its first year, medRxiv rejected 34% of 176 submissios; reasons were not disclosed.⁵

The low rate of on-site comments suggests that preprint servers may not be effective for obtaining feedback to improve dermatology manuscripts prior to journal submission. Almost all of the top 20 dermatologyjournals accept preprints. Therefore, dermatologists may use these preprint servers to assert project ideas and disseminate research quickly and freely but may not receive constructive criticism.

Our study is subject to several limitations. Although our search was extensive, it is possible manuscripts were missed. Article metrics also were not available on all servers, and we could not account for accepted articles that were not yet indexed.

There has been a surge in posting of dermatology preprints in recent years. Preprints have not been peer reviewed, and data should be corroborated before incorporating new diagnostics or treatments into clinical practice. Utilization of preprint servers by dermatologists is increasing, but because the impact is still unknown, further studies on accuracy and reliability of preprints are warranted.

To the Editor:

Preprint servers allow researchers to post manuscripts before publication in peer-reviewed journals. As of January 2022, 41 public preprint servers accepted medicine/science submissions.¹ We sought to analyze characteristics of dermatology manuscripts in preprint servers and assess preprint publication policies in top dermatology journals.

Thirty-five biology/health sciences preprint servers¹ were searched (March 3 to March 24, 2021) with keywords dermatology, skin, and cutaneous. Preprint server, preprint post date, location, metrics, journal, impact factor (IF), and journal publication date were recorded. Preprint policies of the top 20 dermatology journals—determined by impact factor of the journal (https://www.scimagojr.com/)—were reviewed. Two-tailed t tests and χ² tests were performed (P<.05).

A total of 1420 articles were posted to 11 preprint servers between June 20, 2007, and February 15, 2021 (Table 1); 377 (27%) were published in peer-reviewed journals, with 350 (93%) of those published within 1 year of preprint post. Preprints were published in 203 journals with a mean IF of 6.2. Growth in preprint posts by year (2007-2020) was exponential (R²=0.78)(Figure). On average, preprints were viewed 424 times (Table 2), with published preprints viewed more often than unpublished preprints (596 vs 362 views)(P<.001). Only 23 of 786 (3%) preprints with comments enabled had feedback. Among the top 20 dermatology journals, 18 (90%) allowed preprints, 1 (5%) evaluated case by case, and 1 (5%) prohibited preprints.

Our study showed exponential growth in dermatology preprints, a low proportion published in peer-reviewed journals with high IFs, and a substantial number of page views for both published and unpublished preprints. Very few preprints had feedback. We found that most of the top 20 dermatology journals accept preprints. An analysis of 61 dermatology articles in medRxiv found only 51% (31/61) of articles were subsequently published.² The low rate of publication may be due to the quality of preprints that do not meet criteria to be published following peer review.

Preprint servers are fairly novel, with a majority launched within the last 5 years.¹ The goal of preprints is to claim conception of an idea, solicit feedback prior to submission for peer review, and expedite research distribution.³ Because preprints are uploaded without peer review, manuscripts may lack quality and accuracy. An analysis of 57 of thelargest preprint servers found that few provided guidelines on authorship, image manipulation, or reporting of study limitations; however, most preprint servers do perform some screening.⁴ medRxiv requires full scientific research reports and absence of obscenity, plagiarism, and patient identifiers. In its first year, medRxiv rejected 34% of 176 submissios; reasons were not disclosed.⁵

The low rate of on-site comments suggests that preprint servers may not be effective for obtaining feedback to improve dermatology manuscripts prior to journal submission. Almost all of the top 20 dermatologyjournals accept preprints. Therefore, dermatologists may use these preprint servers to assert project ideas and disseminate research quickly and freely but may not receive constructive criticism.

Our study is subject to several limitations. Although our search was extensive, it is possible manuscripts were missed. Article metrics also were not available on all servers, and we could not account for accepted articles that were not yet indexed.

There has been a surge in posting of dermatology preprints in recent years. Preprints have not been peer reviewed, and data should be corroborated before incorporating new diagnostics or treatments into clinical practice. Utilization of preprint servers by dermatologists is increasing, but because the impact is still unknown, further studies on accuracy and reliability of preprints are warranted.

The major classifications of thyroid disease include hyperthyroidism, which is seen in Graves disease, and hypothyroidism due to iodine deficiency and Hashimoto thyroiditis, which have potentially devastating health consequences. The prevalence of hyperthyroidism ranges from 0.2% to 1.3% in iodine-sufficient parts of the world, and the prevalence of hypothyroidism in the general population is 5.3% in Europe and 3.7% in the United States.¹ Thyroid hormones physiologically potentiate α- and β-adrenergic receptors by increasing their sensitivity to catecholamines. Excess thyroid hormones manifest as tachycardia, increased cardiac output, increased body temperature, hyperhidrosis, and warm moist skin. Reduced sensitivity of adrenergic receptors to catecholamines from insufficient thyroid hormones results in a lower metabolic rate and decreases response to the sympathetic nervous system.² Nail changes in thyroid patients have not been well studied.³ Our objectives were to characterize nail findings in patients with thyroid disease. Early diagnosis of thyroid disease and prompt referral for treatment may be instrumental in preventing serious morbidities and permanent sequelae.

Methods

PubMed, Scopus, Web of Science, and Google Scholar were searched for the terms nail + thyroid, nail + hyperthyroid, nail + hypothyroid, nail + Graves, and nail + Hashimoto on June 10, 2020, and then updated on November 18, 2020. All English-language articles were included. Non–English-language articles and those that did not describe clinical trials of nail changes in patients with thyroid disease were excluded. One study that utilized survey-based data for nail changes without corroboration with physical examination findings was excluded. Hypothyroidism/hyperthyroidism was defined by all authors as measurement of serum thyroid hormones triiodothyronine, thyroxine, and thyroid-stimulating hormone outside of the normal range. Eight studies were included in the final analysis. Patient demographics, thyroid disease type, physical examination findings, nail clinical findings, age at diagnosis, age at onset of nail changes, treatments/medications, and comorbidities were recorded and analyzed.

Results

Nail changes in patients with thyroid disease were reported in 8 studies (7 cross-sectional, 1 retrospective cohort) and are summarized in the Table.^4-11 The mean age was 41.2 years (range, 5–80 years), with a higher representation of females (range, 70%–94% female). The most common nail changes in thyroid patients were koilonychia, clubbing, and nail brittleness. Other changes included onycholysis, thin nails, dryness, and changes in nail growth rate. Frequent physical findings were xerosis, pruritus, and alopecia.

Both koilonychia and clubbing were reported in patients with hyperthyroidism. In a study of 32 patients with koilonychia, 22 (68.8%) were diagnosed with hyperthyroidism.¹⁰ Nail clubbing affected 7.3% of Graves disease patients (n=150)⁶ and 5.0% of hyperthyroid patients (n=120).⁷ Dermopathy presented more than 1 year after diagnosis of Graves disease in 99 (66%) of 150 patients as a late manifestation of thyrotoxicosis.⁶ Additional physical features in patients with Graves disease (n=150) were pretibial myxedema (100%), ophthalmopathy (99.0%), and proptosis (88.0%). Non–Graves hyperthyroid patients showed physical features of soft hair (83.3%) and soft skin (66.0%).⁷

Nail brittleness was a frequently reported nail change in thyroid patients (4/8 studies, 50%), most often seen in 22% of autoimmune patients, 19.6% of nonautoimmune patients, 13.9% of hypothyroid patients, and 9.2% of hyperthyroid patients.^5,8 For comparison, brittle nails presented in 10.8% of participants in a control group.⁵ Brittle nails in thyroid patients often are accompanied by other nail findings such as thinning, onycholysis, and pitting.

Among hypothyroid patients, nail changes included fragility (70%; n=50), slow growth (48%; n=50), thinning (40%; n=50), onycholysis (38%; n=50),⁷ and brittleness (13.9%; n=173).⁵ Less common nail changes in hypothyroid patients were leukonychia (9.4%; n=32), striped nails (6%; n=50), and pitting (1.2%; n=173).^5,7,11 Among hyperthyroid patients, the most common nail changes were koilonychia (100%; n=22), softening (83%; n=120), onycholysis (29%; n=14), and brittleness (9.2%; n=173).^5,7,9,10 Less common nail changes in hyperthyroid patients were clubbing (5%; n=120), thinning (4.6%; n=173), and leukonychia (3%; n=120).^5,7

Additional cutaneous findings of thyroid disorder included xerosis, alopecia, pruritus, and weight change. Xerosis was most common in hypothyroid disease (57.2%; n=460).⁴ In 2 studies,^8,9 alopecia affected approximately 70% of autoimmune, nonautoimmune, and hyperthyroid patients. Hair loss was reported in 42.6% (n=460)⁴ and 33.0% (n=36)⁹ of hypothyroid patients. Additionally, pruritus affected up to 28% (n=32)¹¹ of hypothyroid and 16.0% (n=120)⁷ of hyperthyroid patients and was more common in autoimmune (41%) vs nonautoimmune (32%) thyroid patients.⁸ Weight gain was seen in 72% of hypothyroid patients (n=32),¹¹ and soft hair and skin were reported in 83.3% and 66% of hyperthyroid patients (n=120), respectively.⁷ Flushing was a less common physical finding in thyroid patients (usually affecting <10%); however, it also was reported in 17.1% of autoimmune and 57.1% of hyperthyroid patients from 2 separate studies.^8,9

There are limited data describing nail changes with thyroid disease. Singal and Arora³ reported in their clinical review of nail changes in systemic disease that koilonychia, onycholysis, and melanonychia are associated with thyroid disorders. We similarly found that koilonychia and onycholysis are associated with thyroid disorders without an association with melanonychia.

In his clinical review of thyroid hormone action on the skin, Safer¹² described hypothyroid patients having coarse, dull, thin, and brittle nails, whereas in thyrotoxicosis, patients had shiny, soft, and concave nails with onycholysis; however, the author commented that there were limited data on the clinical findings in thyroid disorders. These nail findings are consistent with our results, but onycholysis was more common in hypothyroid patients than in hyperthyroid patients in our review. Fox¹³ reported on 30 cases of onycholysis, stating that it affected patients with hypothyroidism and improved with thyroid treatment. In a clinical review of 8 commonly seen nail abnormalities, Fowler et al¹⁴ reported that hyperthyroidism was associated with nail findings in 5% of cases and may result in onycholysis of the fourth and fifth nails or all nails. They also reported that onychorrhexis may be seen in patients with hypothyroidism, a finding that differed from our results.¹⁴

The mechanism of nail changes in thyroid disease has not been well studied. A protein/amino acid–deficiency state may contribute to the development of koilonychia. Hyperthyroid patients, who have high metabolic activity, may have hypoalbuminemia, leading to koilonychia.¹⁵ Hypothyroidism causes hypothermia from decreased metabolic rate and secondary compensatory vasoconstriction. Vasoconstriction decreases blood flow of nutrients and oxygen to cutaneous structures and may cause slow-growing, brittle nails. In hyperthyroidism, vasodilation alternatively may contribute to the fast-growing nails. Anti–thyroid-stimulating hormone receptor antibodies in Graves disease may increase the synthesis of hyaluronic acid and glycosaminoglycans from fibroblasts, keratinocytes, adipocytes, or endothelial cells in the dermis and may contribute to development of clubbing.¹⁶

Our review is subject to several limitations. We recorded nail findings as they were described in the original studies; however, we could not confirm the accuracy of these descriptions. In addition, some specific nail changes were not described in sufficient detail. In all but 1 study, dermatologists performed the physical examination. In the study by Al-Dabbagh and Al-Abachi,¹⁰ the physical examinations were performed by general medicine physicians, but they selected only for patients with koilonychia and did not assess for other skin findings. Fragile nails and brittle nails were described in hypothyroid and hyperthyroid patients, but these nail changes were not described in detail. There also were studies describing nail changes in thyroid patients; some studies had small numbers of patients, and many did not have a control group.

Conclusion

Nail changes may be early clinical presenting signs of thyroid disorders and may be the clue to prompt diagnosis of thyroid disease. Dermatologists should be mindful that fragile, slow-growing, thin nails and onycholysis are associated with hypothyroidism and that koilonychia, softening, onycholysis, and brittle nail changes may be seen in hyperthyroidism. Our review aimed to describe nail changes associated with thyroid disease to guide dermatologists on diagnosis and promote future research on dermatologic manifestations of thyroid disease. Future research is necessary to explore the association between koilonychia and hyperthyroidism as well as the association of nail changes with thyroid disease duration and severity.

The major classifications of thyroid disease include hyperthyroidism, which is seen in Graves disease, and hypothyroidism due to iodine deficiency and Hashimoto thyroiditis, which have potentially devastating health consequences. The prevalence of hyperthyroidism ranges from 0.2% to 1.3% in iodine-sufficient parts of the world, and the prevalence of hypothyroidism in the general population is 5.3% in Europe and 3.7% in the United States.¹ Thyroid hormones physiologically potentiate α- and β-adrenergic receptors by increasing their sensitivity to catecholamines. Excess thyroid hormones manifest as tachycardia, increased cardiac output, increased body temperature, hyperhidrosis, and warm moist skin. Reduced sensitivity of adrenergic receptors to catecholamines from insufficient thyroid hormones results in a lower metabolic rate and decreases response to the sympathetic nervous system.² Nail changes in thyroid patients have not been well studied.³ Our objectives were to characterize nail findings in patients with thyroid disease. Early diagnosis of thyroid disease and prompt referral for treatment may be instrumental in preventing serious morbidities and permanent sequelae.

Methods

PubMed, Scopus, Web of Science, and Google Scholar were searched for the terms nail + thyroid, nail + hyperthyroid, nail + hypothyroid, nail + Graves, and nail + Hashimoto on June 10, 2020, and then updated on November 18, 2020. All English-language articles were included. Non–English-language articles and those that did not describe clinical trials of nail changes in patients with thyroid disease were excluded. One study that utilized survey-based data for nail changes without corroboration with physical examination findings was excluded. Hypothyroidism/hyperthyroidism was defined by all authors as measurement of serum thyroid hormones triiodothyronine, thyroxine, and thyroid-stimulating hormone outside of the normal range. Eight studies were included in the final analysis. Patient demographics, thyroid disease type, physical examination findings, nail clinical findings, age at diagnosis, age at onset of nail changes, treatments/medications, and comorbidities were recorded and analyzed.

Results

Nail changes in patients with thyroid disease were reported in 8 studies (7 cross-sectional, 1 retrospective cohort) and are summarized in the Table.^4-11 The mean age was 41.2 years (range, 5–80 years), with a higher representation of females (range, 70%–94% female). The most common nail changes in thyroid patients were koilonychia, clubbing, and nail brittleness. Other changes included onycholysis, thin nails, dryness, and changes in nail growth rate. Frequent physical findings were xerosis, pruritus, and alopecia.

Both koilonychia and clubbing were reported in patients with hyperthyroidism. In a study of 32 patients with koilonychia, 22 (68.8%) were diagnosed with hyperthyroidism.¹⁰ Nail clubbing affected 7.3% of Graves disease patients (n=150)⁶ and 5.0% of hyperthyroid patients (n=120).⁷ Dermopathy presented more than 1 year after diagnosis of Graves disease in 99 (66%) of 150 patients as a late manifestation of thyrotoxicosis.⁶ Additional physical features in patients with Graves disease (n=150) were pretibial myxedema (100%), ophthalmopathy (99.0%), and proptosis (88.0%). Non–Graves hyperthyroid patients showed physical features of soft hair (83.3%) and soft skin (66.0%).⁷

Nail brittleness was a frequently reported nail change in thyroid patients (4/8 studies, 50%), most often seen in 22% of autoimmune patients, 19.6% of nonautoimmune patients, 13.9% of hypothyroid patients, and 9.2% of hyperthyroid patients.^5,8 For comparison, brittle nails presented in 10.8% of participants in a control group.⁵ Brittle nails in thyroid patients often are accompanied by other nail findings such as thinning, onycholysis, and pitting.

Among hypothyroid patients, nail changes included fragility (70%; n=50), slow growth (48%; n=50), thinning (40%; n=50), onycholysis (38%; n=50),⁷ and brittleness (13.9%; n=173).⁵ Less common nail changes in hypothyroid patients were leukonychia (9.4%; n=32), striped nails (6%; n=50), and pitting (1.2%; n=173).^5,7,11 Among hyperthyroid patients, the most common nail changes were koilonychia (100%; n=22), softening (83%; n=120), onycholysis (29%; n=14), and brittleness (9.2%; n=173).^5,7,9,10 Less common nail changes in hyperthyroid patients were clubbing (5%; n=120), thinning (4.6%; n=173), and leukonychia (3%; n=120).^5,7

Additional cutaneous findings of thyroid disorder included xerosis, alopecia, pruritus, and weight change. Xerosis was most common in hypothyroid disease (57.2%; n=460).⁴ In 2 studies,^8,9 alopecia affected approximately 70% of autoimmune, nonautoimmune, and hyperthyroid patients. Hair loss was reported in 42.6% (n=460)⁴ and 33.0% (n=36)⁹ of hypothyroid patients. Additionally, pruritus affected up to 28% (n=32)¹¹ of hypothyroid and 16.0% (n=120)⁷ of hyperthyroid patients and was more common in autoimmune (41%) vs nonautoimmune (32%) thyroid patients.⁸ Weight gain was seen in 72% of hypothyroid patients (n=32),¹¹ and soft hair and skin were reported in 83.3% and 66% of hyperthyroid patients (n=120), respectively.⁷ Flushing was a less common physical finding in thyroid patients (usually affecting <10%); however, it also was reported in 17.1% of autoimmune and 57.1% of hyperthyroid patients from 2 separate studies.^8,9

There are limited data describing nail changes with thyroid disease. Singal and Arora³ reported in their clinical review of nail changes in systemic disease that koilonychia, onycholysis, and melanonychia are associated with thyroid disorders. We similarly found that koilonychia and onycholysis are associated with thyroid disorders without an association with melanonychia.

In his clinical review of thyroid hormone action on the skin, Safer¹² described hypothyroid patients having coarse, dull, thin, and brittle nails, whereas in thyrotoxicosis, patients had shiny, soft, and concave nails with onycholysis; however, the author commented that there were limited data on the clinical findings in thyroid disorders. These nail findings are consistent with our results, but onycholysis was more common in hypothyroid patients than in hyperthyroid patients in our review. Fox¹³ reported on 30 cases of onycholysis, stating that it affected patients with hypothyroidism and improved with thyroid treatment. In a clinical review of 8 commonly seen nail abnormalities, Fowler et al¹⁴ reported that hyperthyroidism was associated with nail findings in 5% of cases and may result in onycholysis of the fourth and fifth nails or all nails. They also reported that onychorrhexis may be seen in patients with hypothyroidism, a finding that differed from our results.¹⁴

The mechanism of nail changes in thyroid disease has not been well studied. A protein/amino acid–deficiency state may contribute to the development of koilonychia. Hyperthyroid patients, who have high metabolic activity, may have hypoalbuminemia, leading to koilonychia.¹⁵ Hypothyroidism causes hypothermia from decreased metabolic rate and secondary compensatory vasoconstriction. Vasoconstriction decreases blood flow of nutrients and oxygen to cutaneous structures and may cause slow-growing, brittle nails. In hyperthyroidism, vasodilation alternatively may contribute to the fast-growing nails. Anti–thyroid-stimulating hormone receptor antibodies in Graves disease may increase the synthesis of hyaluronic acid and glycosaminoglycans from fibroblasts, keratinocytes, adipocytes, or endothelial cells in the dermis and may contribute to development of clubbing.¹⁶

Our review is subject to several limitations. We recorded nail findings as they were described in the original studies; however, we could not confirm the accuracy of these descriptions. In addition, some specific nail changes were not described in sufficient detail. In all but 1 study, dermatologists performed the physical examination. In the study by Al-Dabbagh and Al-Abachi,¹⁰ the physical examinations were performed by general medicine physicians, but they selected only for patients with koilonychia and did not assess for other skin findings. Fragile nails and brittle nails were described in hypothyroid and hyperthyroid patients, but these nail changes were not described in detail. There also were studies describing nail changes in thyroid patients; some studies had small numbers of patients, and many did not have a control group.

Conclusion

Nail changes may be early clinical presenting signs of thyroid disorders and may be the clue to prompt diagnosis of thyroid disease. Dermatologists should be mindful that fragile, slow-growing, thin nails and onycholysis are associated with hypothyroidism and that koilonychia, softening, onycholysis, and brittle nail changes may be seen in hyperthyroidism. Our review aimed to describe nail changes associated with thyroid disease to guide dermatologists on diagnosis and promote future research on dermatologic manifestations of thyroid disease. Future research is necessary to explore the association between koilonychia and hyperthyroidism as well as the association of nail changes with thyroid disease duration and severity.

The major classifications of thyroid disease include hyperthyroidism, which is seen in Graves disease, and hypothyroidism due to iodine deficiency and Hashimoto thyroiditis, which have potentially devastating health consequences. The prevalence of hyperthyroidism ranges from 0.2% to 1.3% in iodine-sufficient parts of the world, and the prevalence of hypothyroidism in the general population is 5.3% in Europe and 3.7% in the United States.¹ Thyroid hormones physiologically potentiate α- and β-adrenergic receptors by increasing their sensitivity to catecholamines. Excess thyroid hormones manifest as tachycardia, increased cardiac output, increased body temperature, hyperhidrosis, and warm moist skin. Reduced sensitivity of adrenergic receptors to catecholamines from insufficient thyroid hormones results in a lower metabolic rate and decreases response to the sympathetic nervous system.² Nail changes in thyroid patients have not been well studied.³ Our objectives were to characterize nail findings in patients with thyroid disease. Early diagnosis of thyroid disease and prompt referral for treatment may be instrumental in preventing serious morbidities and permanent sequelae.

Methods

PubMed, Scopus, Web of Science, and Google Scholar were searched for the terms nail + thyroid, nail + hyperthyroid, nail + hypothyroid, nail + Graves, and nail + Hashimoto on June 10, 2020, and then updated on November 18, 2020. All English-language articles were included. Non–English-language articles and those that did not describe clinical trials of nail changes in patients with thyroid disease were excluded. One study that utilized survey-based data for nail changes without corroboration with physical examination findings was excluded. Hypothyroidism/hyperthyroidism was defined by all authors as measurement of serum thyroid hormones triiodothyronine, thyroxine, and thyroid-stimulating hormone outside of the normal range. Eight studies were included in the final analysis. Patient demographics, thyroid disease type, physical examination findings, nail clinical findings, age at diagnosis, age at onset of nail changes, treatments/medications, and comorbidities were recorded and analyzed.

Results

Nail changes in patients with thyroid disease were reported in 8 studies (7 cross-sectional, 1 retrospective cohort) and are summarized in the Table.^4-11 The mean age was 41.2 years (range, 5–80 years), with a higher representation of females (range, 70%–94% female). The most common nail changes in thyroid patients were koilonychia, clubbing, and nail brittleness. Other changes included onycholysis, thin nails, dryness, and changes in nail growth rate. Frequent physical findings were xerosis, pruritus, and alopecia.

Both koilonychia and clubbing were reported in patients with hyperthyroidism. In a study of 32 patients with koilonychia, 22 (68.8%) were diagnosed with hyperthyroidism.¹⁰ Nail clubbing affected 7.3% of Graves disease patients (n=150)⁶ and 5.0% of hyperthyroid patients (n=120).⁷ Dermopathy presented more than 1 year after diagnosis of Graves disease in 99 (66%) of 150 patients as a late manifestation of thyrotoxicosis.⁶ Additional physical features in patients with Graves disease (n=150) were pretibial myxedema (100%), ophthalmopathy (99.0%), and proptosis (88.0%). Non–Graves hyperthyroid patients showed physical features of soft hair (83.3%) and soft skin (66.0%).⁷

Nail brittleness was a frequently reported nail change in thyroid patients (4/8 studies, 50%), most often seen in 22% of autoimmune patients, 19.6% of nonautoimmune patients, 13.9% of hypothyroid patients, and 9.2% of hyperthyroid patients.^5,8 For comparison, brittle nails presented in 10.8% of participants in a control group.⁵ Brittle nails in thyroid patients often are accompanied by other nail findings such as thinning, onycholysis, and pitting.

Among hypothyroid patients, nail changes included fragility (70%; n=50), slow growth (48%; n=50), thinning (40%; n=50), onycholysis (38%; n=50),⁷ and brittleness (13.9%; n=173).⁵ Less common nail changes in hypothyroid patients were leukonychia (9.4%; n=32), striped nails (6%; n=50), and pitting (1.2%; n=173).^5,7,11 Among hyperthyroid patients, the most common nail changes were koilonychia (100%; n=22), softening (83%; n=120), onycholysis (29%; n=14), and brittleness (9.2%; n=173).^5,7,9,10 Less common nail changes in hyperthyroid patients were clubbing (5%; n=120), thinning (4.6%; n=173), and leukonychia (3%; n=120).^5,7

Additional cutaneous findings of thyroid disorder included xerosis, alopecia, pruritus, and weight change. Xerosis was most common in hypothyroid disease (57.2%; n=460).⁴ In 2 studies,^8,9 alopecia affected approximately 70% of autoimmune, nonautoimmune, and hyperthyroid patients. Hair loss was reported in 42.6% (n=460)⁴ and 33.0% (n=36)⁹ of hypothyroid patients. Additionally, pruritus affected up to 28% (n=32)¹¹ of hypothyroid and 16.0% (n=120)⁷ of hyperthyroid patients and was more common in autoimmune (41%) vs nonautoimmune (32%) thyroid patients.⁸ Weight gain was seen in 72% of hypothyroid patients (n=32),¹¹ and soft hair and skin were reported in 83.3% and 66% of hyperthyroid patients (n=120), respectively.⁷ Flushing was a less common physical finding in thyroid patients (usually affecting <10%); however, it also was reported in 17.1% of autoimmune and 57.1% of hyperthyroid patients from 2 separate studies.^8,9

There are limited data describing nail changes with thyroid disease. Singal and Arora³ reported in their clinical review of nail changes in systemic disease that koilonychia, onycholysis, and melanonychia are associated with thyroid disorders. We similarly found that koilonychia and onycholysis are associated with thyroid disorders without an association with melanonychia.

In his clinical review of thyroid hormone action on the skin, Safer¹² described hypothyroid patients having coarse, dull, thin, and brittle nails, whereas in thyrotoxicosis, patients had shiny, soft, and concave nails with onycholysis; however, the author commented that there were limited data on the clinical findings in thyroid disorders. These nail findings are consistent with our results, but onycholysis was more common in hypothyroid patients than in hyperthyroid patients in our review. Fox¹³ reported on 30 cases of onycholysis, stating that it affected patients with hypothyroidism and improved with thyroid treatment. In a clinical review of 8 commonly seen nail abnormalities, Fowler et al¹⁴ reported that hyperthyroidism was associated with nail findings in 5% of cases and may result in onycholysis of the fourth and fifth nails or all nails. They also reported that onychorrhexis may be seen in patients with hypothyroidism, a finding that differed from our results.¹⁴

The mechanism of nail changes in thyroid disease has not been well studied. A protein/amino acid–deficiency state may contribute to the development of koilonychia. Hyperthyroid patients, who have high metabolic activity, may have hypoalbuminemia, leading to koilonychia.¹⁵ Hypothyroidism causes hypothermia from decreased metabolic rate and secondary compensatory vasoconstriction. Vasoconstriction decreases blood flow of nutrients and oxygen to cutaneous structures and may cause slow-growing, brittle nails. In hyperthyroidism, vasodilation alternatively may contribute to the fast-growing nails. Anti–thyroid-stimulating hormone receptor antibodies in Graves disease may increase the synthesis of hyaluronic acid and glycosaminoglycans from fibroblasts, keratinocytes, adipocytes, or endothelial cells in the dermis and may contribute to development of clubbing.¹⁶

Our review is subject to several limitations. We recorded nail findings as they were described in the original studies; however, we could not confirm the accuracy of these descriptions. In addition, some specific nail changes were not described in sufficient detail. In all but 1 study, dermatologists performed the physical examination. In the study by Al-Dabbagh and Al-Abachi,¹⁰ the physical examinations were performed by general medicine physicians, but they selected only for patients with koilonychia and did not assess for other skin findings. Fragile nails and brittle nails were described in hypothyroid and hyperthyroid patients, but these nail changes were not described in detail. There also were studies describing nail changes in thyroid patients; some studies had small numbers of patients, and many did not have a control group.

Conclusion

Nail changes may be early clinical presenting signs of thyroid disorders and may be the clue to prompt diagnosis of thyroid disease. Dermatologists should be mindful that fragile, slow-growing, thin nails and onycholysis are associated with hypothyroidism and that koilonychia, softening, onycholysis, and brittle nail changes may be seen in hyperthyroidism. Our review aimed to describe nail changes associated with thyroid disease to guide dermatologists on diagnosis and promote future research on dermatologic manifestations of thyroid disease. Future research is necessary to explore the association between koilonychia and hyperthyroidism as well as the association of nail changes with thyroid disease duration and severity.