Carpal Tunnel Syndrome
The carpal tunnel is the passageway in the wrist and consists of the arching carpal bones (eight bones in the wrist) and the ligament connecting the pillars of the arch (the transverse carpal ligament). The median nerve and the tendons that connect the fingers to the muscles of the forearm pass through the narrow tunnel.
Carpal tunnel syndrome occurs when the median nerve is compressed because of swelling of the nerve or tendons or a combination of factors that put pressure on the median nerve. The median nerve provides sensation to the palm side of the thumb, index, middle finger, and the inside half of the ring finger. It also gives power to, or innervates, muscles in the forearm and hand that allow a pincher grasp (the ability to grasp an object between the thumb and forefinger). When this nerve becomes impinged, or pinched, numbness, tingling, and sometimes pain of the affected fingers and hand may occur and radiate into the forearm.
While there are many possible causes of carpal tunnel syndrome, the vast majority of people with the condition have no known cause (although there may be a congenital predisposition, such that the carpal tunnel is simply narrower in some people than in others). Any condition that puts pressure on the median nerve at the wrist can cause the syndrome. We do know that excessive repetitive movements of the wrists and hands (such as uninterrupted prolonged typing) can trigger the symptoms of carpal tunnel syndrome. Untreated, the symptoms can become chronic, but when detected early, carpal tunnel syndrome can be treated more easily and recovery is possible in a few months. Severe carpal tunnel syndrome can also be treated, but recovery may take up to a year or longer and may not be complete.
What Are the Symptoms of Carpal Tunnel Syndrome?
Symptoms often include a burning, tingling, or itching numbness in the palm of the hand and thumb, index and middle fingers. Usually, people with carpal tunnel syndrome first notice that their fingers "fall asleep" and become numb at night. The reason they may experience symptoms at night may be the relaxed flexed position of the hand and wrist while sleeping, or the accumulation of fluid that may put pressure around the joint. They often wake up with numbness and tingling in their hands. The feeling of burning pain and numbness may generally run up the center of the person's forearm, sometimes as far as the shoulder. Carpal tunnel syndrome may be temporary and resolve by itself or become persistent and worsen over time.