Ulnar nerve deep branch compression by a ganglion: a review of nine cases

Ulnar nerve compression is common at the elbow, but less common at the wrist. The purposes of this study were to report a series of nine patients with pure ulnar nerve deep branch compression by a ganglion and to evaluate the outcome following a surgical treatment.

A retrospective study was conducted with nine patients from 2000 to 2011. The patients included four male and five female patients. The mean duration of symptoms before surgery was 16 months (range, 5-32 months). Different degrees of muscular atrophy and weakness of the interossei and adductor pollicis muscles were present without sensory loss in the hand. Ganglion excision and decompression of Guyon's canal were performed in all patients. We evaluated postoperative results of this uncommon nerve lesion based on the modified Bishop's scoring system.

The ganglion compressing the deep branch originated from the pisohamate joint in eight cases and from the midpalmar space in one case. At the mean follow-up of 23 months (range, 17-31 months), strength improvement of the grip and tip pinch was achieved in all patients. In comparison, grip strength improved from a mean of 63% of the unaffected side preoperatively to 88% of the unaffected side postoperatively. Tip pinch strength improved from a mean of 61% to 87%. According to the modified Bishop's scoring system, six patients (67%) obtained excellent results, two (22%) had good results, and only one (11%) had a fair result.

A ganglion causing ulnar nerve deep branch compression is rare. Early surgical treatment can result in satisfactory functional recovery.