Healthy Life: Carpal Tunnel Syndrome (Median Nerve Compression) (838)

Healthy life: Carpal Tunnel Syndrome

蘇鎮邦 (Christopher So)：
舒整物理治療師 (Manipulative Physiotherapist) 人類工程師 (Ergonomist)

In the middle of the wrist on the palmer side there is flexor tendons with the median nerve embedded in a tight fascia sheath (Diagram 1). There is virtually no space between these structures. If there is any swelling, compression on these structures will result in pressure on the median nerve. This will cause numbness and pain in the three and a half fingers on the thumb side (Diagram 2). It is common to get burning pain, pins and needles or tingling in these fingers during sleep. In late stage, it can wake the patient. It may be relieved by shaking the affected hand or letting it down on the side of the bed. It does not affect the hand as much during the day unless patients engage in activities such as sewing, using a computer mouse or scissors. In severe case, fingers may become weak and clumsy especially doing fine movements such as doing up buttons, using chopsticks or dropping plates on the floor. Some patients may get atrophy of their hand muscles especially the thumb.

This syndrome occurs in females eight times more than in males, especially in pregnant ladies, or ladies with rheumatic arthritis, menopause or existing tenosynovitis. There are simple tests that can help patients to diagnose this problem. Tinel’s sign is numbness and pain in the three and a half fingers on the thumb side and occurs when light percussion affects the median nerve. However, nerve compression of the neck or cervical spines (C5,6,7) can reproduce similar symptoms. The crucial difference is that the little finger and both sides of the ring finger can be affected. Also, the symptoms tend to travel down towards the tips of the fingers whereas with carpal tunnel syndrome the symptoms tend to travel up from the wrist to forearm.

Another simple test called the Phalen’s test can be used. When the patient’s hand is folded up towards the palmer side for a length of time (1-2 minutes), numbness and tingling will occur. Once the symptoms come on, it should be stopped so as not to cause the problem to flare up.

Generally, there were no symptoms at the beginning. Therefore, the causes of the problem have not been noted. However, early detection and treatment mostly results in good relief. If the condition becomes severe or when there is muscle atrophy, injections and an operation are necessary.

(Diagram 1)

(Diagram 2)