Diagnosis: Posttraumatic tache noir
Posttraumatic tache noir (also known as talon noir on the volar aspect of the feet) is a subcorneal hematoma. The diagnosis is made clinically.
Our patient was a competitive baseball player, and he noted that the knob of his baseball bat rubbed the hypothenar eminence of his nondominant hand when he took a swing. The sheer force of the knob led to the subcorneal hematoma. Tache noir was high on the differential due to the author’s clinical experience with similar cases.
Tache noir occurs predominantly in people ages 12 to 24 years, without regard to gender.1 The condition is commonly found in athletes who participate in baseball, cricket, racquet sports, weightlifting, and rock climbing.1-3 Talon noir occurs most commonly in athletes who are frequently jumping, turning, and pivoting, as in football, basketball, tennis, and lacrosse. One should have a high index of suspicion for this diagnosis in patients who participate in any sport that might lead to shearing forces involving the volar aspect of the hands or feet.
Confirmation is obtained through a simple procedure. Dermoscopic evaluation of tache/talon noir will reveal “pebbles on a ridge” or “satellite globules.” Confirmation of tache/talon noir can be made by paring the corneum with a #15 blade, which will reveal blood in the shavings and punctate lesions.4
Other lesions may havea similar appearance
Tache noir can be differentiated from other conditions by the presence of preserved architecture of the skin surface and punctate capillaries beneath the stratum corneum. The differential diagnosis includes verruca vulgaris, acral melanoma, and a traumatic tattoo.
Continue to: Verruca vulgaris