Carpal tunnel syndrome causes a dull ache in the wrist and forearm with pain which may radiate into the hand and fingers. It is often worse at night.
We explain the symptoms, causes and treatment including exercises and surgery.
Symptoms usually increase gradually over time and may initially only be present at night. It can occur in one or both wrists at the same time. A dull ache in the wrist and forearm is felt with pain which may radiate into the thumb and four fingers of the hand, but not the little finger.
The patient may feel sensations of tingling or burning in the hand or four fingers. Pain is often worse at night and can radiate into the forearm, elbow or shoulder. In addition weakness in the fingers and hands may be experienced.
Carpal tunnel syndrome tests can be done to reproduce symptoms and help diagnosis:
- Phalen's sign is where the patient bends the wrists to push the backs of the hands together, holding for 1 minute. If the test is positive then tingling that radiates into the thumb, index finger and the middle half of the forth finger will be felt.
- Tinel's sign is where the therapist taps with two fingers over the palm side of the wrist. Carpal tunnel syndrome could be considered if there is a tingling sensation or other symptoms are reproduced.
- Investigations may also be performed to confirm the diagnosis including MRI scan, ultrasound imaging, electromyography or a nerve conduction study.
What causes carpal tunnel syndrome?
Symptoms are caused by compression of the median nerve in the wrist as it passes through a narrow channel in the wrist called the carpal tunnel along with the tendons of the flexor digitorum superficialis and flexor pollicis longus muscles of the forearm.
The tunnel can narrow creating pressure on the nerve for a number of reasons:
- Traumatic wrist injury such as wrist sprains and broken wrists.
- Repetitive strain injury or RSI caused by over use of the wrist.
- Pregnancy which causes fluid retention in the wrist.
- Use of vibrating machinery which may cause damage or inflammation to the soft tissues.
- It may be congenital meaning some people naturally have a smaller, narrower carpal tunnel.
All of these conditions can cause a narrowing of the space through which the median nerve passes. Symptoms are three times more common in women, probably because they have a smaller carpal tunnel. It also has a higher prevalence in people with diabetes and other conditions which directly affect the nervous system. It usually occurs first in the dominant hand and sometimes but not always occurring as well in the non dominant hand. Some professions are more at risk of developing carpal tunnel syndrome, especially people working on an assembly line, who are continually repeating the same movement.
Carpal tunnel syndrome treatment
Treatment should initially be conservative which means without surgery. If after conservative treatment has been tried for a few weeks and not been successful then surgery is often considered.
Rest - Rest from activities which cause pain or make it worse. Continuing to use a painful wrist will not allow inflammation to settle down and soft tissues to heal. This may include work related activities such as typing at a keyboard, DIY or sport specific training including racket sports. If you are an athlete then use this opportunity to work on another aspect of your game or maintain fitness with aerobic exercise.
Carpal tunnel wrist splint - A carpal tunnel wrist splint can be worn to immobilize the wrist joint helping you to rest the joint whilst allowing some function of the hand. The wrist splint is usually made of a thick supportive neoprene material and have a metal spoon or support along the wrist to prevent movement.
Ice or cold therapy - If there is inflammation and swelling present, using a form of cold therapy will help to relieve this. Applying ice or a specialist cold wrap to the wrist area for 10 minutes at a time can be done hourly in the early stages, reducing in frequency as required.
Medication - Your Doctor may also prescribe anti-inflammatory medication such as ibuprofen to reduce inflammation, or diuretics to clear fluid retention.
Acupuncture - Other treatments, which may be worth trying include acupuncture which has been linked to an improvement in carpal tunnel syndrome symptoms. Acupuncture is performed by inserting needles of various lengths and diameters into specific points over the body. The needle is usually inserted, rotated and then either removed immediately or left in place for several minutes.
Injections - If symptoms do not improve other options include Corticosteroids or lidocaine injections. If all of this treatment fails and symptoms persist over a 6 month period, surgery may be required.
Following a period of immobilization, stretching and strengthening exercises can be used to help prevent symptoms returning. All exercises should be performed pain-free. If pain occurs, go back a step or rest for longer. Initially mobility and gentle stretching exercises should be done to restore full pain free range of motion at the joint. Later static strengthening exercises can begin which do not involve movement and finally normal strength can be restored by dynamic exercises involving movement with resistance bands or dumbelle weights.
See more on carpal tunnel syndrome exercises.
A carpal tunnel release is a very common operation, which involves cutting the carpal ligament to make more space for the median nerve. This can either be done as an arthroscopic operation (keyhole), or as an open release, where a 5-6cm incision is made. It is a straightforward procedure which is usually carried out on an outpatient basis. Your hand and wrist will be bandaged and may be placed in a sling for a few days to help it rest and reduce swelling.