The carpal tunnel is an anatomical space that is found between the palmar surface of the carpal bones of the wrist and the annular or transverse carpal ligament in the dorsal area. The median nerve passes through the interior of the tunnel, as well as the superficial and deep muscle tendons of the fingers, and the large flexor muscle of the thumb.
Pins and needles and tingling of the hand that may cause discomfort during the night that improves on shaking the hand.Daytime pain in the hand that increases with activity. Muscle weakness of the thumb that manifests with difficulty in gripping and pinching.
In carpal tunnel syndrome, the mechanism by which the nerve is damaged is due to the increase in the pressure within the tunnel due to intrinsic and extrinsic causes that trigger discomfort in the wrist and the hand. This increase in pressure produces a space conflict, with inflammation of the tendon sheaths of the flexor tendons within the tunnel and ischaemia of the median nerve.
The Phallen sign consists of maintaining the wrist in forced flexion for 1 minute. If there is compression of the median nerve in the carpal tunnel, tingling usually appears in the palm of the hand and in the fingers that depend on the median nerve, although the discomforts are normally produced in the tips of the fingers.
Avoid repetitive movements of the wrist that are forced. If these are unavoidable, try to maintain the wrist in slight extension when the hands are making movements. Use wrist supports or special keyboards when using the computer.
Conservative treatment of the carpal tunnel is bases on adopting ergonomic measures in those manual activities that may provoke it, use splints to reduce the pressure in the carpal tunnel, rehabilitation treatment and local corticosteroid injections with or without local anaesthetic.
The use of a splint is recommended, especially, during the night in order to maintain the wrist in a neutral position, although it can also be used all day depending on the pain and discomfort of the patient.
Rehabilitation treatment based on combined therapies using the application of analgesic electrotherapy and exercises, with muscle and tendon stretching and strengthening exercises at wrist level, can alleviate the pain and improve mobility of the wrist.