Sonographic diagnosis of recurrent ulnar nerve compression by ganglion cysts

Lesions of the ulnar nerve are the most common causes of paralysis of a peripheral nerve. The cubital tunnel (or sulcus ulnaris) syndrome is the second most frequent compression syndrome of the upper extremities after the carpal tunnel syndrome. We report our findings in a patient who suffered from cubital tunnel syndrome and underwent subcutaneous anterior transposition, a surgical procedure in which the ulnar nerve is removed from the osseus fibrotic canal and replaced anteriorly in the subcutaneous space on the flexion side of the elbow. Nine years after surgery, the patient developed a recurrent entrapment syndrome due to a pair of ganglion cysts located in the cubital area. These cysts could be not be diagnosed by routine electrophysiologic methods but were successfully identified by ultrasonography.