Talon noir in Adult
Talon noir tends to affect the posterior foot, the heel, the lateral foot, and the palm. Athletic events often produce lateral shearing forces that cause tearing of blood vessels in the papillary dermis. This creates punctate papillary dermal hemorrhages, leading to extravasation of blood into the epidermis and intracorneal retention of hemoglobin. Because of its location in the stratum corneum, it cannot be cleared by phagocytic cells.
Basketball, lacrosse, football, soccer, and cross-country running are frequent causes of talon noir.
The condition is asymptomatic, and because it is painless, the etiological events are often unrecognized. Because of the discoloration and generally rapid acquisition, patients may be concerned that they have an acral melanoma.
S90.30XA – Contusion of unspecified foot, initial encounter
21143006 – Calcaneal petechiae
Differential Diagnosis & Pitfalls
- Acral melanoma – If dyspigmentation does not resolve with superficial paring, the concern for melanoma is increased. Lesions suspected of being even a possible melanoma should be pursued with appropriate referral to dermatology and a possible biopsy.
- Acral nevus – Also a melanocytic process that is readily appreciated on biopsy.
- Traumatic tattoo – Implantation of exogenous pigmented material, such as graphite or other carbon material, is not Hemoccult positive.
- Verruca vulgaris – Sometimes dilated and thrombosed capillaries may be seen in the center of the wart, but usually this is very punctate in nature. Disruptions of skin architecture, such as interruption of skin lines, also indicate that a verruca is present.
- Tinea nigra – A rare fungal infection with an organism that produces its own melanin-based pigment. The fungus is readily seen on biopsy because of this endogenous pigment production.