The carpal tunnel is a passageway in the wrist area and specifically on the palm side of your hand. The passageway is used by the median nerve and nine tendons that provide control and sensation to important parts of the hand such as your thumb and first three fingers. The pressure of the median nerve can cause carpal tunnel syndrome. However the causes are not completely known. We spoke with Dr. Alberto Lazzerini, Head of Hand Surgery at Humanitas to find out more.
What are the causes of carpal tunnel syndrome?
“The causes are generally unknown,” says Dr. Lazzerini. Several conditions can increase the pressure in the tunnel: causing a swelling of the sheaths of the tendons, dislocation of the wrist, fractures and the presence of osteoarthritis. Even the typical water retention of some pregnant women can cause swelling inside the tunnel. Furthermore the syndrome may be associated with thyroid diseases, diabetes and rheumatoid arthritis.
What are some of the symptoms of carpal tunnel syndrome?
Carpal tunnel syndrome is characterized by a tingling in the first fingers of the hand, resulting in numbness. This occurs primarily in the night hours and it can also be associated with pain. The symptoms can affect the entire upper limb. Pain can be intermittent and then become constant. In severe cases, patients also report that they have a weaker grip and reduced sensitivity in the fingers, often causing them to drop objects.
Although we speak of carpal tunnel syndrome, the symptoms must involve the area innervated by the median nerve.
How is it diagnosed?
The specialist will hear about the symptoms reported by the patient during the visit. Their aim is to detect any pre-existing medical conditions, and to examine the daily use of your hands, and to discover traumas or injuries reported previously. The patient will then be subjected to:
- X-rays of hands, to highlight arthritis or fractures.
- Electromyography, to confirm or exclude the presence of a flattening of the nerve in the carpal tunnel and to check whether there are other pressure points.
- laboratory tests, to investigate associated medical conditions.
When is surgery necessary?
“The intake of anti-inflammatory drugs and the use of a night-time brace can reduce pain”, explains Dr. Lazzerini. In the presence of important symptoms though and according to the results of the electromyography, surgical intervention may be necessary. Only surgery makes it possible to resolve the situation, thus freeing the median nerve trapped in the tunnel.
However when the specialist suggests avoiding surgery it is important to do so, as it may worsen the situation, with possible sensory and motor deficits.