What is Carpal Tunnel?

Carpal Tunnel syndrome is entrapment of a large nerve in the arm at the wrist called the median nerve. This nerve supplies sensation to the inside portion of the thumb, index, and middle fingers in most individuals and also some fibers that control strength in the thumb. This nerve runs from the arm into the hand through a small tunnel at the wrist called the carpal tunnel. There is a thick ligament that makes up part of this tunnel which can sometimes become too thick and can compress the nerve. When the nerve is compressed, it becomes irritated and painful, and its function can be affected.

There are many conditions that can be associated with the development of carpal tunnel syndrome such as pregnancy, rheumatoid arthritis, B6 deficiency, etc. Many patients have a history of excessive, repetitive wrist motion such as through a job or a hobby. In the majority of patients with carpal tunnel syndrome, a specific causative factor cannot be identified.

How is it diagnosed?

Carpal tunnel syndrome is diagnosed by history, careful neurologic exam, and a test called NCV (nerve conduction velocity). Conservative treatment is usually tried first which consists of nonsteroidal anti-inflammatory drugs and a wrist splint. In patients who fail to improve with conservative therapy or patients who have significant sensory loss or weakness of the thumb muscle or shrinkage of that muscle (atrophy), surgical therapy is recommended.

What can be done?

This is a fairly simple surgical procedure which can be done on an outpatient basis in most patients. An incision of about one inch is made in the palm of the hand and the thick ligament overlying the nerve is divided, which allows the nerve to have more room in the carpal tunnel. The skin is then sutured closed.

Patients will need to avoid any strenuous use of the hand for approximately two to three weeks after the surgery. The neurosurgeon can better delineate that convalescent period according to the patient’s specific situation.