Carpal tunnel syndrome (CTS) is a wrist condition resulting from increased pressure on the median nerve at the wrist, much like if the nerve was pinched.
Patients often experience symptoms such as numbness or tingling, and pain in the fingers, hand, or arm. Inside the wrist, nine tendons pass from the wrist to the hand through a space called the carpal tunnel, and carpal tunnel syndrome occurs when the tunnel swells and pressure is put on the nerve. When the swelling and pressure gets large enough to affect the nerve's workings, then pain, numbness, or tingling may be felt in the hand and fingers.
Causes of Carpal Tunnel Syndrome
The cause of carpal tunnel syndrome is frequently unknown because the pressure on the nerve can come from a variety of conditions and can occur when the lining of the flexor tendons swell, a condition known as tenosynovitis. However, the tunnel can also be narrowed as a result of joint dislocations or fractures, or even from arthritis or keeping the wrist bent for long periods of time. The swelling and symptoms can also result from fluid retention during pregnancy although this condition usually passes shortly after giving birth. Carpal tunnel syndrome has also been linked with diabetes, some thyroid conditions, and rheumatoid arthritis, and a combination of causes is likely.
Signs & Symptoms of Carpal Tunnel
The most common symptoms of carpal tunnel syndrome include pain, numbness, or tingling in the thumb, index, middle, and ring fingers. The symptoms, which may come in combination, are more pronounced at night. Additionally, symptoms are often noticed when performing routine daily activities (e.g., turning pages or driving).
A weaker grip or tendency to drop things is common, and occasional clumsiness may be a sign. If the syndrome advances to a severe case, sensation in the thumb or digits may be permanently lost, and the muscles of the thumb may slowly shrink in a condition called thenaratrophy. Thenaratrophy can cause difficulty with pinching.
Diagnosis & Medical History
To correctly diagnose carpal tunnel syndrome, one of our hand surgeons will take a detailed medical history during your initial visit. This history will include any prior injuries as well as how the hands are, or have been, used. Arthritis or fractures may be checked with an x-ray and laboratory tests may be used to check for the presence of other medical conditions that may be associated. To confirm the diagnosis, a nerve conduction study or NCV may be performed along with an electromyogram or EMG. These tests may also identify other possible nerve conditions.
Non-Surgical & Surgical Treatments
Many of our patients are relieved of the pain, numbness, and tingling associated with carpal tunnel syndrome without surgery.
Such symptoms are often treated by properly identifying and treating medical conditions, by changing habitual patterns of how the hands are used, or by keeping the wrist in a splint that will keep it straight, thereby reducing the pressure on the effected nerve. A wrist splint worn at night may lessen the symptoms that interfere with sleep, and an injection of steroids into the carpal tunnel may reduce the swelling around the nerve and help relieve the pain, numbness, or tingling.
If the symptoms are severe or don't respond to the above treatments, a physician then considers the possibility of carpal tunnel surgery or carpal tunnel release to make more room around the nerve. The surgery will trim the ligament on the top or palm side of the tunnel (fig 3) to relieve pressure on the nerve. While the location of the incision used for this surgery may vary, enlarging the tunnel and reducing pressure on the nerve is the desired result. After the surgery is performed, there may be soreness around the incision for several weeks or months, and several months may pass before wrist and hand strength returns to normal. In severe cases, the symptoms of carpal tunnel syndrome may not be entirely eliminated, not even following surgery.