Carpal Tunnel Syndrome

 

‘Carpal Tunnel Syndrome’ is a relatively common complaint affecting around 100 people in every 100,000 in the UK and is more frequently seen in women than men.  It is caused by pressure on the Median Nerve one of the main nerves supplying the arm and hand. The median nerve originates in the neck, passes through the armpit into the arm, then tracks down the inside of the elbow too the hand. It has both a motor (muscles output side) supply and a sensory (input) element. The median nerve innervates the majority of the muscles in the forearm and some hand muscles as well as the sensory part.

The nerve subdivides as it descends into the arm as follows:

• The Palmar Cutaneous nerve– innervates the skin of the lateral (thumb side) palm. This bit does not pass through he carpal tunnel so is usually unaffected.
• The Median nerve enters the hand via the carpal tunnel– where it terminates by dividing into two branches; the Recurrent branch – innervates the muscles of the thumb (thenar) muscles and the Palmar digital branch – innervates the palmar surface and fingertips of the thumb, index and middle finger.

Where the nerve passes through an anatomical ‘narrow point’ on the palm side of the wrist it can be ‘squashed’ causing nerve symptoms such as numbness, tingling, aching and weakness in the hand. The ‘carpal tunnel’ has very little space within it and through it must pass with some blood vessels and tendons into the hand. The tissues of the palm make its roof and the small bones of the wrist form its floor. A small increase in local pressure, normally due to fluid build up ‘oedema’ will cause an increase in the pressure on the median nerve and therefore symptoms.

In terms of who is likely suffer from Carpal Tunnel Syndrome, well there are many causes of an increase in oedema at the wrist including: RSI, repetitive wrist flexing tasks such as sewing, writing, driving, computer use, osteoarthritis of the wrist bones and pregnancy (because of water retention) and last obesity. Sometimes more serious conditions can cause the condition such as, local fractures, diabetes, hypothyroidism, rheumatoid arthritis along many others.

Taking a decent case history by an osteopath or doctor will generally provide a reasonably good diagnosis often confirmed with simple tests there and then. Medical tests can be undertaken to confirm this definitively later such as X-Rays of the wrist and electrical nerve testing of the Median Nerve.

There are a variety of treatment methods available but reducing stress on the wrist will help.   Changing repetitive activities, using ergonomic mice and wrist supports at work and generally reviewing your environment (see your HR/occupational health person at work for advice) assists matters. There are ‘wrist splints’ available that can be used, initially at night, sometime during the day if necessary. There are also changes you can make in the workplace to reduce the stress on your wrist.    Manual treatments such as Osteopathy do help as they reduce the local stress and more broadly improve the function of the arm, shoulder, back and neck.

Medications recommended for this condition are primarily anti-inflammatory in nature, however in more severe cases local steroid injections may help. Surgery on the wrist to releases the tunnel and reduced or removes pressure on the nerve is a reasonably common final resort and pretty effective.

As usual in most condition’s prevention is better than cure so the usual advice applies. When undertaking any activity take care of yourself, make it as easy as possible, take lots of breaks, use the best equipment you can afford and get advice if you are not sure.