Ulnar nerve entrapment in Guyon's canal due to a lipoma

Guyon's canal syndrome is an ulnar nerve entrapment at the wrist or palm that can cause motor, sensory or combined motor and sensory loss due to various factors. In this report, we presented a 66-year-old man admitted to our clinic with a history of intermittent pain in the left palm and numbness in 4(th) and 5(th) finger for two years. His neurological examination revealed a sensory impairment in the right fifth finger. Also, physical examination displayed a subcutaneous mobile soft tissue in ulnar side of the wrist. Electromyographic examination confirmed the diagnosis of type-1 Guyon's canal syndrome. Under axillary blockage, a lipoma compressing the ulnar nerve was excised totally and ulnar nerve was decompressed. The symptoms were improved after the surgery and patient was symptom free on 3rd postoperative week.