Carpal tunnel syndrome is a progressively painful condition caused by a pinched nerve in the wrist. Carpal tunnel syndrome happens when pressure builds up from swelling in this tunnel putting pressure on the nerve causing pain and numbness in the fingers.
Anatomy
The carpal tunnel is a narrow structure at the base of the palm. It is formed by the bones of the wrist and a strong band of connective tissue called the transverse carpal ligament. Increased pressure within the tunnel affects the function of the median nerve. The median nerve controls feeling in the thumb, index finger and long fingers. The tendons that bend the fingers and thumb, called flexor tendons, also travel through the carpal tunnel.
Causes
Pressure on the nerve can happen several ways, including:
- Swelling of the lining of the flexor tendons, called tenosynovitis
- Joint dislocations
- Fractures
- Arthritis
- Fluid retention during pregnancy
The situations listed above can narrow the carpal tunnel or cause swelling in the tunnel. Thyroid conditions, rheumatoid arthritis and diabetes can also be associated with carpal tunnel syndrome.
Signs and Symptoms
Symptoms of this condition can include:
- Pain
- Numbness
- Tingling
- Weak grip
- Occasional clumsiness
- Tendency to drop things
The numbness or tingling most often takes place in the thumb, index, middle and ring fingers. The symptoms usually are felt during the night but may also be noticed during daily activities such as driving or reading a newspaper. In severe cases, sensation and strength may be permanently lost.
Diagnosis
A detailed history including medical conditions, the patient’s profession, activity level, and any prior injuries is important in diagnosing carpal tunnel syndrome. An x-ray may be taken to check for arthritis or a fracture. In some cases, laboratory tests may be done. Electrodiagnostic studies are also a possibility to confirm the diagnosis and check for other possible nerve problems.
Treatment
Symptoms may often be relieved without surgery. Some treatment options are:
- Changing patterns of hand use (helps reduce pressure on the nerve)
- Keeping the wrist splinted in a straight position (helps reduce pressure on the nerve)
- Wearing wrist splints at night (helps relieve symptoms that interfere with sleep)
- Steroid injections into the carpal tunnel (helps reduce swelling around the nerve)
When is surgery recommended?
When symptoms are severe or do not improve, surgery may be needed to make more room for the nerve. Pressure on the nerve is decreased by cutting the ligament that forms the top of the tunnel on the palm side of the hand Following surgery, soreness around the cut area may last for several weeks or months. The numbness and tingling may disappear quickly or slowly. Recovery may take several months. Carpal tunnel symptoms may not completely go away after surgery, especially in severe cases.
Endoscopic Surgery
Surgery for carpal tunnel syndrome can be done both open and endoscopically. In endoscopic surgery, the surgeon uses an endoscope—a telescope-like device with a tiny camera attached to it—to see inside the carpal tunnel and perform the surgery through a small single incision in your wrist. Endoscopic surgery may allow faster recovery and less postoperative discomfort than open release surgery. The procedure is performed under general or local anesthesia and does not require an overnight hospital stay.
What is the recovery time?
Following surgery, soreness may last for several weeks or months. There are no restrictions on activities. Patients may return to work as soon as the post surgical pain allows. Those patients with high demand professions may need more time before returning. Heavy gripping and lifting may cause pain for a while. Numbness and tingling may disappear quickly or slowly, and it may take several months for strength in the hand and wrist to return to normal. Carpal tunnel symptoms may not completely go away after surgery, especially in severe cases. As with all surgical procedures, specific recovery time varies by patient and demand.
Gregory Frechette, MD
Dr. Frechette is an orthopedic surgeon with specialized training in hand, wrist and elbow surgery. He graduated from the University of Vermont College of Medicine and completed an orthopedic surgery residency at Mount Sinai Hospital in NYC. He then completed the Harvard Hand and Upper Extremity Fellowship at Beth Israel Deaconess Medical Center. He has a special interest in wide-awake minor hand surgery as well as elbow instability.