It is caused by compression of the median nerve in the wrist which is responsible for carrying physical sensations such as touch from your hand and carrying nerve signals from the brain to the hand. The nerve can become compressed if the tissues in inside the tunnel become swollen or the tunnel narrows over time. Risk factors include family history, conditions such as diabetes, under active thyroid gland or rheumatoid arthritis, pregnancy and wrist injuries.
The symptoms develop gradually and are more evident at night or early in the morning. Patients can experience a dull ache and discomfort in the hand reaching up the forearm to the upper arm. A burning, prickling sensation, swelling or dry skin may also occur. Repetitive actions of the hand and wrist can aggravate the symptoms.
A GP will initially want to assess hand and wrist flexibility and test for sensitivity looking for muscle weakness. A blood test, detailed nerve study using electrode, or an ultrasound scan may also be used to judge the extent of the condition.
Sometimes it improves without treatment with the symptoms subsiding after a few months, but a range of surgical and non-surgical techniques are available that can relieve pressure on the median nerve. A consultant is best placed to judge the best treatment as the symptoms and pathways vary from patient to patient. A wrist splint can provide relief in a few weeks and corticosteroid injections help reduce inflammation.
Carpal tunnel release surgery can be performed on an outpatient basis with a reliable keyhole surgery procedure under local anaesthetic. The surgeon can make tiny modifications to the ligaments allowing a complete and permanent cure.