What is the Carpal Tunnel?
The carpal tunnel is the term for the space on the palm side of the wrist through which the tendons that flex the fingers and wrist, and the median nerve pass.
This space is formed by the semicircle of wrist bones (known as the carpus) and a strong ligament as a roof across the top.
What's the median Nerve?
There are three main nerves that supply the arm: the ulna, radial and median. They all come from the neck and take a different course down the arm giving sensation to different areas of the arm and supplying different muscles.
The median nerve goes across the front of the shoulder, down the middle of the front of the upper arm, across the front of the elbow, down the front of the middle of the forearm, through the carpal tunnel to the hand.
- It supplies the sensation to the thumb, 1st, 2nd finger and the thumb side of the ring finger on the palm side of the hand.
- It works a muscle called pronator teres. If you are sitting with your elbows bent and your palms facing the ceiling then turn your palms down to the floor; it is pronator teres that does this.
- It works the muscles in the pad of the thumb
So what's Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome is compression of the median nerve as it passes through the carpal tunnel at the wrist.
What are the Symptoms of Carpal Tunnel Syndrome?
Because Carpal Tunnel Syndrome is caused by pressure on the median nerve as it passes through the tunnel the main symptom is pins and needles and/ or numbness in the area of the hand that the median nerve supplies i.e. the thumb, 1st, 2nd and thumb side of the third finger on the palm side of the hand.
Shooting pain may sometimes be felt going up the course of the nerve i.e. shooting up the forearm
Symptoms are often worse at night and during the day when lifting or gripping something.
Who gets Carpal Tunnel Syndrome?
Women are three times more likely than men to get carpal tunnel syndrome. If you have a close relative with CTS you are more prone to it yourself, possibly because of the inherited shape and size of your wrist
Size of tunnel
People who have a relatively small carpal tunnel are more likely to get compression of the nerve as it goes through the tunnel
Repeated activity particularly with your wrist in extension puts pressure on the nerve. This includes work on a production line, and prolonged computer work.
Secondary to other conditions
- Pregnancy: due to fluid retention
- Menopause: hormonal changes
- Hypothyroidism, Rheumatoid arthritis, Systemic lupus Erythematosus (auto immune diseases): If untreated these diseases cause the body to attack its own tissues
- Post Trauma: previous fractures of the wrist can disrupt the carpus and reduce the space within the tunnel
- Obesity: increases the pressure within the tunnel
- Diabetes: diabetic neuropathies
- Chronic kidney Dysfunction: due to a build up of a protein called beta 2 microglobulin
- Dysfunction elsewhere along the course of the nerve: the neck is a common place where the nerve may be compressed, either directly causing referred symptoms, or making the nerve more sensitive further along its course.
What's the Treatment?
Treatment of any other condition that may be causing CTS
If for instance CTS is secondary to hypothyroidism taking a correct dose of levothyroxine may help to relieve the carpal tunnel symptoms.
The single most important treatment for carpal tunnel syndrome is to alter the way that you are doing any activities which are causing pressure on the nerve. Generally speaking activities where the wrist is in extension (pulled backwards) increase the pressure and it's best where possible to do things with the wrist in a neutral (straight position)
Take frequent rests
Every 15 minutes either take a break or alter your activity.
Local modalities to reduce inflammation and exercises. Nerves are inelastic and cannot be stretched. An irritated nerve can become very painful if repeatedly pulled on, however nerves do like movement and will respond well to been gently glided in and out of the tunnel with specific exercises.
Splints keep the wrist in a neutral position and help to rest the area.
A local steroid injection into the tunnel can reduce inflammation thus giving more relative space within the tunnel and relieving pressure on the nerve.
The standard surgery for carpal tunnel involves making an incision on the roof of the tunnel thus increasing the relative space in the tunnel and taking pressure off the nerve.
Disclaimer: The information on this page is written to help you understand your injury. There are many possible causes for hand pain and should you have any concerns you should always seek advice from a qualified health professional such as a Chartered Physiotherapist or your GP.