Description

The carpal tunnel is a location in the hand where the median nerve and specific tendons enter the hand. The transverse carpal ligament spans the roof of the carpal tunnel and connects to bones of the hand on the medial and lateral sides. Carpal Tunnel Syndrome occurs when the median nerve is compressed inside of the tunnel. This can occur due to inflammation, crowding of the carpal tunnel contents, acute injury or repetitive use injuries.

What are the causes?

Carpal Tunnel Syndrome is caused by compression of the median nerve in the carpal tunnel. This pressure may occur as a result of swelling of the surrounding tendons due to various causes. People whose occupations require extensive repetitive use of the hand, such as typists, carpenters, and illustrators tend to be at increased risk of developing Carpal Tunnel Syndrome. When a wrist fracture causes increased pressure on the nerve, it is referred to as Traumatic Carpal Tunnel Syndrome. Finally, patients with medical conditions associated with soft tissue swelling may develop Carpal Tunnel Syndrome. These include: diabetes, hypothyroidism, arthritis and/or pregnancy.

What are the symptoms?

Patients with Carpal Tunnel Syndrome may complain of pain, numbness or tingling in the medial side of the hand including the palm side of the thumb and first two and a half fingers. Numbness, tingling or pain may be felt specifically in the thumb, index, middle finger, and half of the ring finger because this area of the hand is innervated by the median nerve. The pain may go up into the forearm and may be prominent at night. Activity that involves use of the hand makes the pain worse. Patients may also complain of cold intolerance and difficulty grasping objects.

How is it diagnosed?

Your surgeon will perform a physical exam looking for muscle wasting at the base of thumb. Tapping the compressed median nerve may produce a painful sensation in the hand. Carpal Tunnel Syndrome may also be assessed by holding both wrists flexed together in a bent position which may also elicit pain in the distribution of the median nerve. X-rays in most patients are usually normal. An EMG, or electromyogram, can also help to confirm the diagnosis. An electromyogram test sends electrical impulses through the muscle and into the nerve and records how long the impulse takes to travel from one point to the next. Delayed impulses result from nerves that are compressed or injured. The longer the delay, the greater the nerve compression.

How is it treated?

Non-operative

Your surgeon may recommend avoiding activities that cause pain in the hand. A brace may be recommended to immobilize the wrist, both at night and during activity. Rest may help decrease swelling of the tendons in the carpal tunnel. Physical therapy or a home exercise program may also be recommended to relieve symptoms. Anti-inflammatory medications may be prescribed to also decrease pain and swelling. Finally, injections into the carpal tunnel may also reduce inflammation and relieve symptoms.

Operative

If non-operative treatment fails to relieve the pain, your surgeon may suggest releasing the transverse carpal ligament, which forms the roof of the carpal tunnel. This can be accomplished through an open incision or endoscopically through a very small incision. Cutting the transverse carpal ligament allows the tunnel to expand, relieving the pressure on the median nerve.