The carpal tunnel is a narrow passage on the palmar aspect of the wrist. The “roof” of the tunnel is the transverse carpal ligament. The “floor and walls” consist of the carpal bones. Through the tunnel itself run the flexor tendons and the median nerve. It is said nerve that when irritated or compressed, causes the typical signs and symptoms of carpal tunnel syndrome (CTS):
These symptoms are most commonly felt in the thumb, first, second and sometimes third fingers, on the palm side of the hand. In more severe cases this pain however can travel up to the elbow. A typical diagnostic sign in addition to the above symptoms is that pain is worse at night and that in order to relieve them, people feel the need to shake their hands (as though removing excess water after washing your hands).
Tests to diagnose CTS
- Phalen’s Sign: With the elbows at shoulder height, the dorsal (back) aspect of the hands are pushed against one another. This brings the wrists into flexion, further compressing the median nerve. If after approximately 60 seconds the signs and symptoms increase, it is a positive indicator of CTS.
- Tinel’s Sign: With the wrist and hand resting on a surface palm side up, the physician/therapist will tap over the carpal tunnel. A positive test is one which causes increased tingling, numbness or pain in the thumb or fingers, further indicating the possibility of CTS.
- Nerve Conduction Study: A specialist may confirm CTS with nerve conduction testing. These tests measure the speed an electrical impulse travels along the median nerve. People with CTS show slower conduction speeds, and in severe cases, testing can show muscular deterioration in the region.
The first line of treatment for CTS is conservative management. Anti-inflammatory medication can provide short term pain relief, though is not considered a long term cure. Alternatively a direct steroid injection into the tunnel has been shown to have an effect in some patients, when done in conjunction with physiotherapy and ergonomic changes to the home and workplace.
Physiotherapy for CTS focuses on stretching and strengthening exercises mainly for the wrist and fingers, but in severe cases, an exercise programme for the entire upper arm will be incorporated into the patient’s rehabilitation. In addition, electrotherapy modalities can be used to ease painful symptoms and re-educate muscular activity. A physiotherapist or occupational therapist will also give advise on ergonomic changes that can be made in order to prevent the problem reoccurring.
In the event that conservative management is unsuccessful, your physician will possibly recommend surgical intervention. Under local anaesthetic, the “roof” of the tunnel, the transverse carpal ligament is cut in order to relieve the pressure within. There may be some pain and swelling post surgery, though will correct post-op management, these symptoms will resolve within a few weeks and the symptoms of CTS will have gone completely.