Carpal Tunnel Syndrome

What is Carpal Tunnel Syndrome?

There is an anatomically defined space located in the wrist called the carpal tunnel. Wrist bones form the floor and sides of the tunnel while a strong band of connective tissue covers the top of the tunnel called the transverse carpal ligament. Through this tunnel pass the median nerve and nine tendons. Many different conditions can cause either thickening of the ligament or swelling of the tendons within the carpal tunnel. The end result is excess pressure on the median nerve leading to numbness, tingling, clumsiness, and pain in the hand.

What Causes Carpal Tunnel Syndrome?

Any condition that causes increased pressure on the median nerve in the carpal tunnel will lead to carpal tunnel syndrome. Some common factors are listed below.

  • Repetitive or prolonged bending and grasping with the hand and wrist
  • Broken or dislocated bones of the wrist
  • Wrist arthritis (especially rheumatoid arthritis)
  • Diabetes
  • Thyroid conditions
  • Dupuytren's Disease
  • Hormonal changes associated with menopause
  • Pregnancy

Although any of the above conditions may be present alone or in combination, most cases have no identifiable cause.

What Are the Symptoms of Carpal Tunnel Syndrome?

The median nerve supplies sensation to the thumb, index, middle and ring fingers while also controlling the muscles of the thumb. Therefore the conditions that lead to carpal tunnel syndrome will interfere with the function of this nerve. The most common complaints are of numbness and tingling of the hand and fingers. Often these symptoms are felt at night but may also be noticed during daily activities such as driving or reading a newspaper. Some patients may also notice that they drop things, are clumsy, and have a weaker grip. In severe cases sensation to the thumb, index, middle and ring fingers may be lost while the muscles at the base of the thumb atrophy.

How is Carpal Tunnel Syndrome Diagnosed?

A detailed history including medical conditions, work history, and whether there were any previous injuries to the wrist is important. On physical exam the doctor may elicit an electric-like shock when he/she taps over the course of the median nerve at the wrist. The physician may also be able to elicit symptoms by holding pressure on the median nerve at the wrist for 30 seconds or having the patient hold their wrists bent for one minute. An X-ray may be taken to check for other causes of the complaints such as arthritis or a fracture. In some cases blood work will be done if diabetes or thyroid disease is a suspected culprit. Often special tests called a nerve conduction study/electromyogram may be done to check for other sites of nerve problems and to determine the severity of the disease.

How is Carpal Tunnel Syndrome Treated?

Most mild cases may be treated without surgery. Often activity modification or workspace changes may allow the wrist to rest and decrease inflammation with the tunnel itself. Wrist splints are often added to the regimen of rest. These braces are worn at night to keep ones wrist from bending excessively. Anti-inflammatory medication taken by mouth or injected into the carpal tunnel may also help relieve the symptoms. The effectiveness of non-surgical treatment is often dependent on early diagnosis and treatment.

When symptoms are severe and do not improve with nonsurgical treatment, surgery may be needed to decrease pressure on the nerve. This can be done by releasing the ligament, which comprises the roof of the carpal tunnel. Surgical incisions vary slightly but the goal is the same ....to decrease pressure on the median nerve. This surgery is usually performed in an outpatient facility and the patient is not generally required to stay over night. Following the surgery, soreness around the incision may last for several weeks or months. The numbness and tingling may disappear quickly or slowly depending on the severity and length of the disease process. It may take several months for strength in the hand and the wrist to return to normal. In some severe not all the symptoms will resolve completely.

Rocco Barbieri, M.D.
Medical Director
Hand Center at Southern Pointe