The Nervous System
Lesson 9, Page 10 of 19

The symptoms of Alzheimer's disease can be mimicked by all of the above.

Carpal Tunnel Syndrome

Carpal Tunnel Carpal tunnel syndrome refers to the symptom complex which results when the median nerve is entrapped or pinched in the carpal tunnel—the tunnel between the bones of the wrist through which the nerve passes to enervate the hand. The median nerve supplies sensation to the thumb, index finger, middle finger, and half of the ring finger. It also supplies a branch to the thenar muscles of the thumb.

One of the first symptoms of Carpal Tunnel Syndrome is numbness in the distribution of the median nerve. This is usually followed by pain in the same area. The pain can radiate up the arm to the shoulder and neck. If the condition continues it can lead to weakness in one's ability to grasp.


What Causes Carpal Tunnel Syndrome

The carpal tunnel not only contains the median nerve, but also the tendons of the forearm that are responsible for the flexion of the fingers (grasp). When these tendons, and the sheaths through which they glide, become inflamed due to overuse or arthritis, they swell and take up more space in the carpal tunnel. Since the tunnel is not able to expand, the swollen tendons and their sheaths pinch the median nerve resulting in the symptoms of carpal tunnel syndrome.

The usual medical treatment for carpal tunnel syndrome is surgery. The transverse ligament of the wrist, which crosses the carpal tunnel, is cut to allow more room in the tunnel. Although it works for some people, this surgery has a poor success rate since the resulting scar tissue, which tends to contract over time, can sometimes exert even more pressure on the carpal tunnel than was previously the case.

True of False:
Surgery for carpal tunnel syndrome, the medical treatment of choice for this condition, has a very high success rate.


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