The Ulnar Nerve
The ulnar nerve travels behind the bone on the inside of the elbow (often referred to as the "funny bone") and then along the medial, or inside, aspect of the forearm and across the wrist on the small-finger side of the wrist into the hand.  It supplies the muscles inside the hand, as well as sensation (feeling) to the small finger and half of the ring finger.

The Ulnar Tunnel
The ulnar tunnel is a tunnel through which the ulnar nerve travels at the wrist level.  This tunnel is also called Guyon's canal and is superficial to the transverse carpal ligament at the wrist.

Symptoms
Compression of the ulnar nerve at the wrist level causes pain in this region of the wrist, with pain and tingling radiating into the ring and small fingers of the hand, and numbness in this distribution.  Occasionally there also is weakness of the muscles in the hand, with decreased dexterity and strength, but this does not usually occur with entrapment of the nerve at this level and more often involves problems in the forearm, elbow, or neck.

Treatment
Conservative nonsurgical methods of treatment include splinting of the wrist and changing the activities that brought on the initial problem.  Oral antiinflammatory medications, as well as a cortisone injection into the region, may also be helpful.

Surgery
If nonsurgical methods do not succeed for a period of approximately three months and there is ongoing deterioration, then surgical release may ultimately be necessary if the patient is unable to work and perform daily activities.

Healing after Surgery
Following surgery, hand therapy is initiated to restore strength while the wrist heals, and to assist with a gradual progression back to full use of the hand and wrist.