Description

A 92 year-old woman with history of carpal tunnel release ten years ago, consulted for 1-year history of painless subungual ulcers on the second and third fingers of the right hand (Figure 1). Physical examination also showed a short distant phalanx on the second right finger. No sclerodactyly, telangiectasias or calcifications were present. Capillaroscopy and blood test showed no abnormalities. A biopsy disclosed epidermal ulceration with mild chronic inflammation without signs of vasculitis or thrombosis. Hand X-rays revealed bone resorption in the distal phalanx of the right index finger (Figure 2). An electroneuromyography disclosed severe median nerve damage. A diagnosis of an ulcerative variant of Carpal Tunnel Syndrome was made and the patient was referred to the traumatologist for a newly surgical decompression of the median nerve.

Carpal tunnel syndrome is the most frequent type of entrapment neuropathy, being more prevalent in women than in men. The compression of the median nerve leads to an elevated pressure in the carpal tunnel, which produces ischemia of the median nerve, resulting in pain, paraesthesia, weakness and atrophy [1]. Cutaneous involvement in CTN is rare. The presence of painless ulcerative-mutilating acral lesions typically involving the second and third fingers may lead to suspect the diagnosis [2,3]. An increased awareness of particular clinical picture seems important in order to establish an early diagnosis that may permit to prevent potential bone involvement and mutilating deformities.

References

1. Requena C, Requena L, Blanco S, et al. Acral ulcerations and osteolysis, a severe form of the carpal tunnel syndrome. Br J Dermatol. 2004; 150: 166-7.
2. Gomes TF, Kieselova K, Teixeira V, et al. Clinical Characteristics of Ulcerating Carpal Tunnel Syndrome Among Older Adults in Portugal. JAMA Dermatol. 2021; 157: 731-3.
3. Perdan-Pirkmajer K, Praprotnik S, Tomšič M. Digital ulcers as the first manifestation of carpal tunnel syndrome. Rheumatol Int. 2011; 31: 685-6.