Carpal tunnel syndrome is caused by compression of the median nerve. One of the most important nerves in the hand, the median nerve controls the muscles around the bottom of the thumb and provides sensation in the three biggest fingers and the thumb. The nine flexor tendons that flex the thumb and fingers also extend through the carpal tunnel. As can be guessed, space is limited in the carpal tunnel, and it can’t stretch or otherwise increase its size.

What Causes Carpal Tunnel Syndrome?

Carpal tunnel syndrome develops when the tunnel narrows and/or the synovium swells up. The synovium is a group of tissues that surround the flexor tendons and keep them lubricated to make it easier to move the fingers. Both situations result in the median nerve being compressed.

Carpal tunnel syndrome is most common in women and older people. Factors that increase a patient’s susceptibility to the condition include the following:

  • Repetitive hand use, like typing, that causes the flexor tendons to swell
  • Pregnancy
  • Extreme extension or bending of the wrist or hand for a long time
  • Heredity
  • Certain conditions like rheumatoid arthritis and diabetes increase the chances of developing carpal tunnel syndrome

What are the Symptoms?

A patient with carpal tunnels syndrome can have the following symptoms:

  • Numbness, burning, pain, and tingling particularly in the index, middle, and ring fingers and the thumb
  • Tingling or pain that travels from the forearm up to the shoulder
  • Occasional sensations that feel like electrical shocks that spread to the thumb and three biggest fingers
  • Clumsiness and feebleness in the hand that make it hard to do things like buttoning clothes
  • Increased tendency to drop things due to weakness or a loss of awareness of where one’s hand is

Carpal tunnel syndrome is generally not caused by a given injury, and most cases develop gradually. At first, the symptoms tend to come and go. As the condition gets worse, the symptoms last for longer times and/or occur more frequently.


Without treatment, carpal tunnel syndrome will only get worse. Since untreated carpal tunnel syndrome can become severe enough to require surgery, it is best to diagnose and treat it early. If the patient has a mild case, the doctor can try non-surgical methods like having the patient wear a or splint or brace at night to keep the wrist straight and reduce pressure on the median nerve.

To schedule a consultation, contact us at Plymouth Bay Orthopedic Associates in Plymouth, Duxbury and Sandwich, MA today!