GUYON'S CANAL SYNDROME DUE TO A SYNOVIAL CYST.

We present a case of Guyon's canal syndrome caused by a synovial cyst within the left wrist of a 48-year-old female patient. The patient presented pain and paresthesia in the region of the ulnar nerve, with loss of muscle strength and left-hand deformity. Electroneuromyography showed a compression of the ulnar nerve at the wrist level.