Cubital Tunnel Syndrome
Cubital tunnel syndrome refers to chronic compression of the ulnar nerve at the elbow. The ulnar nerve is responsible for providing sensation to the ring and small fingers, as well as one half of the hand. Some of the fine muscles in the hand as well as one of the muscles in the forearm that enable a person to perform power grip are also controlled by the ulnar nerve.
Very frequently, the ulnar nerve is compressed as it courses behind the medial epicondyle of the elbow in an area called the cubital tunnel. Rarely, the nerve may be compressed at the wrist, a condition known as ulnar tunnel syndrome. With prolonged or advanced compression, muscle atrophy (shrinkage of hand muscles) and weakness with pinch and grip are also seen.
It is rare to see cubital tunnel syndrome in children, but it may be seen in all other age groups including teenagers. Occasionally it is caused by an injury to the elbow, but most often it is caused by holding the elbow in a prolonged position of flexion. For example, holding a cell phone to the ear for a long time or falling asleep with a hand under the pillow are two positions requiring prolonged elbow flexion, which may bring about ulnar nerve symptoms. Very rarely, it is caused by anatomic abnormalities such as an extra muscle.
Cubital Tunnel Treatment
Treatment involves paying attention to how the hand and elbow are used during the day. Though it is okay to move and flex the elbow, patients should avoid holding the elbow flexed for long periods of time. Hands-free devices for phones may be used, and sitting back away from a keyboard so that the elbows do not have to be tucked in for long periods of time may help. When sleeping, a pillow or rolled towel can be fastened to the front of the arm with rubber bands or tape, to create a quick and cheap splint to prevent elbow flexion at night. Commercial splints are also available for this purpose. If none of these are comfortable, an occupational therapist can sometimes make a custom molded form fitting splint for the patient.
The majority of patients do well with night splinting and daytime activity modifications. For the few patients who do not get better after a few months of this treatment, surgery is the best treatment. This involves surgically decompressing the nerve and, in some cases, moving the nerve around to the front of the elbow (known as nerve transposition). These are usually day surgeries.
Figure: Intraoperative photo of a patient following decompression of the left ulnar nerve at the elbow
Immediately after surgery, the elbow may be immobilized in a soft dressing or even a rigid plaster dressing for comfort. Sutures are removed about a week later and patients are encouraged to begin stretching exercises. Almost all patients recover their motion within a month and experience tremendous relief of pain and burning after the surgery. For patients with more severe compression, return of sensation and strength is variable and usually takes months (sometimes years).