C. Ralph Daniel Iii, MD

To the Editor:
Macro- or microtrauma to nails can cause and/or exacerbate chronic diseases such as ingrown nails, onycholysis, onychauxis, onychogryposis, and hallux valgus (bunions). This trauma also can break the anatomic barrier of the hyponychium, thereby creating a portal for dermatophytes and other organisms to penetrate the nail apparatus.¹

For many years, one author (C.R.D.) has used the following demonstration to communicate to patients how improper shoe fit may cause toenail trauma. The patient’s shoe is flipped 180° and placed toe-to-toe with the patient’s foot (Figure). Most patients can comprehend the relationship between their shoe fit and their toenail disease when they see this demonstration. We have termed it toe-to-toe sign.

The foot and shoe are toe-to-toe, demonstrating the narrow toe box in comparison to the actual toes (A). This comparison is accentuated when the shoe is placed over the foot with toes splayed from standing (B).

Narrow toe box is the usual culprit. The toe-to-toe sign best emphasizes this relationship. This sign serves as a powerful tool when demonstrating how much the foot widens when bearing full weight, and how forces of ambulation and foot strike can damage the nails with narrow-toed footwear. This trauma is compounded with high-heeled shoes that force the toes forward. However, proper shoe fit may compete with idealized shoe style. It is not until patients realize the relationship between improper shoe fit, foot strike, and toe/toenail trauma that they can make long-term decisions that favorably impact their toes and toenails.

To the Editor:
Macro- or microtrauma to nails can cause and/or exacerbate chronic diseases such as ingrown nails, onycholysis, onychauxis, onychogryposis, and hallux valgus (bunions). This trauma also can break the anatomic barrier of the hyponychium, thereby creating a portal for dermatophytes and other organisms to penetrate the nail apparatus.¹

For many years, one author (C.R.D.) has used the following demonstration to communicate to patients how improper shoe fit may cause toenail trauma. The patient’s shoe is flipped 180° and placed toe-to-toe with the patient’s foot (Figure). Most patients can comprehend the relationship between their shoe fit and their toenail disease when they see this demonstration. We have termed it toe-to-toe sign.

The foot and shoe are toe-to-toe, demonstrating the narrow toe box in comparison to the actual toes (A). This comparison is accentuated when the shoe is placed over the foot with toes splayed from standing (B).

Narrow toe box is the usual culprit. The toe-to-toe sign best emphasizes this relationship. This sign serves as a powerful tool when demonstrating how much the foot widens when bearing full weight, and how forces of ambulation and foot strike can damage the nails with narrow-toed footwear. This trauma is compounded with high-heeled shoes that force the toes forward. However, proper shoe fit may compete with idealized shoe style. It is not until patients realize the relationship between improper shoe fit, foot strike, and toe/toenail trauma that they can make long-term decisions that favorably impact their toes and toenails.

To the Editor:
Macro- or microtrauma to nails can cause and/or exacerbate chronic diseases such as ingrown nails, onycholysis, onychauxis, onychogryposis, and hallux valgus (bunions). This trauma also can break the anatomic barrier of the hyponychium, thereby creating a portal for dermatophytes and other organisms to penetrate the nail apparatus.¹

For many years, one author (C.R.D.) has used the following demonstration to communicate to patients how improper shoe fit may cause toenail trauma. The patient’s shoe is flipped 180° and placed toe-to-toe with the patient’s foot (Figure). Most patients can comprehend the relationship between their shoe fit and their toenail disease when they see this demonstration. We have termed it toe-to-toe sign.

The foot and shoe are toe-to-toe, demonstrating the narrow toe box in comparison to the actual toes (A). This comparison is accentuated when the shoe is placed over the foot with toes splayed from standing (B).

Narrow toe box is the usual culprit. The toe-to-toe sign best emphasizes this relationship. This sign serves as a powerful tool when demonstrating how much the foot widens when bearing full weight, and how forces of ambulation and foot strike can damage the nails with narrow-toed footwear. This trauma is compounded with high-heeled shoes that force the toes forward. However, proper shoe fit may compete with idealized shoe style. It is not until patients realize the relationship between improper shoe fit, foot strike, and toe/toenail trauma that they can make long-term decisions that favorably impact their toes and toenails.