CARPAL TUNNEL SYNDROME
What is the carpal tunnel?
The carpal tunnel is a tunnel-like structure in the wrist and the base of the hand. It is quite narrow and is rigid because the floor and walls are formed by the wrist bones and the roof is formed by a strong band of tissue called the Flexor retinaculum. This tunnel allows passage to the tendons which move the fingers and thumb. In addition it also contains the median nerve. This is an important nerve which provides sensation or feeling to the palm of the hand. It typically provides a feeling to the thumb, index and long fingers and half of the ring finger. It also controls the small muscles at the base of the thumb.
What is carpal tunnel syndrome?
This occurs when there is increased pressure on the median nerve in the carpal tunnel. Anything which can produce swelling in the confined space of the carpal tunnel can result in increased pressure on this nerve. In most cases of carpal tunnel syndrome no cause is found. However sometimes it can be related to various factors such as hormonal changes in pregnancy, diabetes, thyroid disorders or overuse.
What are the symptoms of carpal tunnel syndrome?
The most common symptoms are tingling, discomfort and numbness in the hand. This may be felt in the entire hand or mainly in the thumb index and long fingers. These symptoms may be accompanied by electric shock- like symptoms in the affected hand. Typically these symptoms are worse at night and may wake the patient up. Hanging the affected hand over the side of the bed or shaking the hand typically improves the symptoms. Daytime symptoms are typically worse during activities such as driving, holding up a newspaper to read or holding a telephone to one’s ear. As the condition progresses, there may be a feeling of weakness or clumsiness in the affected hand. The patient may complain of dropping objects. Initially the symptoms may be intermittent but later on they can become constant and progressively become more severe.
How is it diagnosed?
Carpal tunnel syndrome can be diagnosed with confidence on the basis of the history and a thorough clinical examination. Your doctor will look for evidence of muscle wasting, altered sensation in the hand, and provocation of symptoms on certain manoeuvres.
Will any tests be required?
Nerve tests be performed to confirm the diagnosis particularly if the history and examination is inconclusive. These tests can be useful if there is doubt about the level of pressure on the nerve ie whether it is being compressed higher up in the arm or even in the neck rather than in the carpal tunnel. The nerve tests however may be negative in the presence of carpal tunnel syndrome in about 10% of patients. Is it If an underlying disorder is suspected that the various blood tests or x-rays may be ordered.
What happens if I ignore the symptoms?
In most people with carpal tunnel syndrome, the symptoms progressively get worse with time. If left untreated, the chronic pressure on the nerve may result in permanent damage to the nerve.
How is carpal tunnel syndrome treated?
Initially your GP may try nonsurgical treatment. This may include the use of a brace for a splint on the wrist. This is especially useful to relieve night symptoms. Anti-inflammatory medications and modification of activities may be useful. If these simple measures do not work your GP may try a steroid injection into the carpal tunnel. These injections over and provide relief but in many cases the relief is only temporary. Injections are unlikely to be successful in more severe cases. When simple nonoperative measures fail, then your GP will refer you to an orthopaedic surgeon specialising in upper limb surgery.
What is the surgical treatment for carpal tunnel syndrome?
The surgical treatment is known as a carpal tunnel decompression. It is a simple procedure involving a small incision in the base of the palm. The roof of the carpal tunnel is divided thus relieving the pressure on the median nerve. This is done very carefully in order to avoid damage to the nerve. The skin is then stitched up using absorbable sutures (which dissolve on their own) in most cases. The procedure is nearly always done under a local anaesthetic as a day case in which the patient walks in and walks out without the need for a hospital bed. The operation usually takes about 10 to 15 minutes to perform.
What is the recovery after carpal tunnel decompression?
Initially you will have a bulky bandage on your hand. You must try to keep your hand elevated and move your fingers as much as possible. This will help to reduce swelling. The bulky bandage can be removed after 24 hours. Underneath the bandage you will have a small adhesive plaster which should be left undisturbed until your first follow-up appointment in 1 to 2 weeks. During this time you should try to keep the wound dry. You will be able to use the hand for simple tasks such as writing or holding a glass of water etc. The skin generally heals in about 7 to 10 days. You will be seen by a hand therapist who will instruct you on various exercises, scar massage and scar desensitisation measures. Return to driving may take 2 to 3 weeks. Return to work depends upon your occupation. Earlier return to work may be facilitated by modification of tools, tasks and work environment.
How successful is surgery?
Most patients’ symptoms improve after surgery. Generally pain and tingling improve quickly, numbness can take some weeks to disappear and weakness may take considerably longer. Most patients have return of grip and pinch strength within 2 to 3 months after surgery. However it is well-known that in those patients with long-standing carpal tunnel syndrome recovery is slow and may not be complete.