Carpal tunnel release is surgery to treat carpal tunnel syndrome -- pain and weakness in the hand caused by pressure on the median nerve at the wrist.

The carpal tunnel is composed of two "walls" -- the deep wall is the bones of the wrist and the superficial wall is a thick ligament located just under the skin on the palm side of the wrist. The median nerve and the tendons that flex the fingers to form a fist pass through this tunnel.

Carpal tunnel surgery involves 1 or 2 small incisions over the palm of the hand. The surgery can be performed using a small camera attached to a monitor (endoscopic).

The surgeon will cut the carpal ligament to release pressure on the nerve passing through. Some surgeons will remove tissue surrounding the nerve, especially if the tissue is swollen or irritated (as is often found in arthritis patients).

The surgeon will then usually close the skin and tissues underneath, but only over the carpal ligament, leaving the carpal tunnel uncovered. Other surgeons reattach the carpal ligament after lengthening it.

After the surgery, your wrist will probably be in a splint or heavy bandage for about a week. Then you will begin motion exercises or a physical therapy program.

The results of carpal tunnel release for carpal tunnel syndrome are generally very good.

Patients with symptoms of carpal tunnel syndrome usually have non-surgical treatments first. These include:

• Anti-inflammatory medications
• Occupational therapy
• Workplace modification
• Wrist splints

If these treatments do not improve symptoms, you may need an injection of steroids into the carpal tunnel.

If none of the treatments help, most surgeons will use an EMG to test the electrical activity of the median nerve. If the test finds that the problem is carpal tunnel syndrome, carpal tunnel release surgery is an option.

Risks for any anesthesia include the following:

• Allergic reactions to medications
• Problems breathing

• Bleeding
• Infection

Risks of carpal tunnel release include:

• Failure of the surgery to improve symptoms
• Injury to the median nerve or its branches
• Rarely, injury to another nerve or blood vessel (artery or vein)
• Scar sensitivity

Carpal tunnel release can improve strength and decrease pain in most patients, if these patients are good candidates for the surgery. The procedure improves pain, nerve tingling, and numbness better than it improves muscle weakness.

The longer you have had symptoms, the longer the recovery time and the less fully you may recover.

This surgery is usually done on an outpatient basis. Complete recovery can take anywhere from several weeks to a year, depending on how severely the nerve has been damaged.

A splint may be used to reduce wrist motion for the first few days after surgery. Don't delay moving the wrist for too long, though, because it can become stiff.

The longer the symptoms lasted before surgery, and the more severely damaged the nerve appears at surgery, the longer the recovery time.

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