Compression of the medial branch of the deep peroneal nerve, relieved by excision of an os intermetatarseum. A case report.

The authors report a case of direct compression of the medial branch of the deep peroneal nerve by an os intermetatarseum in a 52-year-old female patient who was referred to their Institution because of pain over the dorsum of her left foot associated with paraesthesias in the first web space. Examination disclosed a positive Tinel sign over the dorsal aspect of the first metatarsal bone. Plain radiographs revealed a small, irregular accessory ossicle on the dorsum of the left foot, between the medial cuneiform and first and second metatarsals. At operation, the os intermetatarseum was found to impinge on the medical branch of the deep peroneal nerve. Excision of the os intermetatarseum and nerve decompression was performed. After four years, the patient has normal function and is completely relieved of her symptoms.