Cubital Tunnel Syndrome
(See also Overview of Hand Disorders.)
Cubital tunnel syndrome is a disorder caused by compression (pinching) of the ulnar nerve at the elbow.
Repetitive use of the elbow can cause cubital tunnel syndrome.
Symptoms include numbness and a pins-and-needles sensation of the ring and little fingers and pain in the elbow.
Doctors base the diagnosis on an examination and, if needed, the results of nerve function tests.
Treatment includes physical therapy and a splint, or sometimes surgery.
The cubital tunnel is called a tunnel because it is the narrow passageway through which the ulnar nerve passes around the elbow on its way to the wrist and hand. The ulnar nerve provides sensation to the little finger, ring finger, and the side of the hand. Because the ulnar nerve passes close to the surface of the skin at the elbow (“funny bone”), it is easily damaged by repeatedly leaning on the elbow, by bending the elbow for prolonged periods, or sometimes by abnormal bone growth in the area. It is less common than carpal tunnel syndrome. Baseball pitchers are prone to cubital tunnel syndrome because of the extra twist of the arm required to throw a pitch called a slider.
Symptoms of cubital tunnel syndrome include numbness and a pins-and-needles sensation of the ring and little fingers and pain in the elbow. Eventually, weakness of the hand, particularly of the ring and little fingers, may develop. Weakness may also interfere with the ability to pinch using the thumb and index finger and the ability to grip with the hand because most of the small muscles in the hand are controlled by the ulnar nerve. Severe, chronic cubital tunnel syndrome can lead to muscle wasting (atrophy) and a clawlike deformity of the hand.
Doctors often base the diagnosis of cubital tunnel syndrome on an examination. However, nerve conduction studies may be needed to help pinpoint the exact area of nerve damage, especially if surgery is being considered.
People with mild cases of cubital tunnel syndrome undergo physical therapy, wear a splint at night to avoid overbending the elbow, and avoid pressure over the elbow. An elbow pad worn during the day can be helpful.
About 85% of people who do not respond to splinting or who have more severe cases of nerve compression may benefit from surgery, which usually consists of releasing pressure on the nerve.