Decompression of the ulnar nerve at the level of the elbow. The nerve is explored through the same incision at three points where it can be trapped:
Just above the elbow where the nerve passes under a ligament (‘Arcade of Struthers’)
At the inner side of the elbow where it runs in a groove between the most prominent bone of the elbow (olecranon) and a bony prominence at the inner side (medial condyle). You can actually feel the nerve in this groove.
Just below the elbow where it goes deeper into the forearm between two muscles (two heads of flexor carpi ulnaris muscle).
There are variations of the operative technique. Some surgeons simply decompress the nerve at the three levels. In some cases, where the nerve despite decompression is still under pressure when bending the elbow (this can be assess during surgery) the nerve is moved in front of the medial epicondyle (above). This is called nerve transposition. A few surgeons remove the medial epicondyle to allow more space for the nerve to move when bending the elbow. In my own practice, a simple decompression produces satisfactory results in most cases but a transposition might be necessary depending on the findings during surgery.
Ulnar nerve syndrome which has not responded to non-operative treatment or is causing a significant or progressive hand weakness.
Bleeding, Infection, neurological deficit including paralysis resulting in permanent numbness or hand weakness (claw deformity -see Ulnar nerve syndrome ), no improvement of symptoms, recurrence of symptoms due to scarring. Overall, the risks, in particular the serious risks are very small (<5%).