Cubital Tunnel Syndrome: An Entrapment Neuropathy Which May Arise from Vascular Malformation

Vascular malformation as a cause of cubital tunnel syndrome has not yet been reported. Cubital tunnel syndrome (CuTS), the most common entrapment neuropathy of the ulnar nerve at elbow level, is also the second most common entrapment neuropathy in the upper extremity, regardless of carpal tunnel syndrome. Here, we report CuTS due to vascular malformation in a 63-year-old woman. The ulnar nerve at the distal part of tunnel was markedly compressed. There was no connection between the lesion and the ulnar nerve. The diagnosis was made by using histopathology, and thereafter the lesion was fully resected. Pain in her ring and little fingers disappeared one month after resection of the malformation.