Carpal Tunnel Syndrome is extremely common, and is a very misunderstood condition. In recent years, it has received much coverage in the press but is still not completely understood, even by the scientific community. The media has branded this condition as an occupational disease because of workers linking pain in their hands to repetitive activities, such as typing or assembly line work. Despite popular opinion, this condition is not caused by repetitive activity, although repetitive activity, such as typing, can aggravate it. Carpal Tunnel Syndrome simply means that there is a compression of the median nerve in the hand. The roof of this tunnel is a structure called the transverse carpal ligament.
Besides the median nerve, there are tendons which flex the fingers and thumb which run through the canal. When the lining around these tendons is inflamed, there is less space for the nerve, and it becomes compressed; this is easiest to think of as a pinched nerve.
This compression of the median nerve leads to the symptoms of Carpal Tunnel Syndrome
The symptoms most often reported with Carpal Tunnel Syndrome are numbness and tingling in the hand, which often begins at night. There may also be pain and weakness in the hand, particularly in the thumb. If allowed to progress for many years untreated, this could lead to atrophy of the muscles at the base of the thumb. The diagnosis of Carpal Tunnel Syndrome is made based on simple clinical tests and patient symptoms, and confirmed by a nerve conduction study. This study measures the velocity and the latency of the nerve impulses across the median nerve at the wrist, and can tell the physician if the patient has a compression of the median nerve.
This condition most commonly occurs in middle-aged women, often premenopausal. It can be caused by chronic conditions, such as diabetes, gout, or thyroid disease, even when these conditions are controlled with medications. It is also commonly seen in women in their third trimester of pregnancy. When any of these other conditions are ruled out, the condition is labeled idiopathic, meaning it is caused by an unknown process. Carpal Tunnel Syndrome often coincides with related conditions such as tendinitis in the fingers (trigger finger), or tendinitis in the wrist. For example, DeQuervain’s tendinitis leads to pain in the wrist at the base of the thumb.
The treatment for Carpal Tunnel Syndrome is often directed at decreasing the inflammation of the tendons. Injections of steroids, such as cortisone, can lead to a temporary decrease in the swelling. This will temporarily allow the median nerve more room in the carpal tunnel, and relieve the pain.