Carpal tunnel syndrome occurs when the median nerve, one of the major nerves that provides innervation to the hand, is pinched in the carpal tunnel. The carpal tunnel is a narrow space on the palm side of the wrist. The “floor” of the tunnel is formed by the wrist bones; the roof is created by a tough piece of tissue called the flexor retinaculum. If the carpal tunnel opening becomes constricted for whatever reason, then pressure is exerted on the median nerve. The patient will develop symptoms such as burning, numbness, and tingling in the hand involving mostly the thumb, index, third, and part of the fourth fingers. If the pressure continues without adequate treatment, then the ability to use those fingers to grip will also worsen.
The carpal tunnel can be narrowed as a result of trauma, edema (fluid build-up as occurs during pregnancy), repetitive motion, thyroid disease, acromegaly (growth hormone excess), gout, and various forms of arthritis (rheumatoid arthritis is the most common).
The diagnosis is suspected by taking a careful history. Further corroboration is established through a careful physical examination by a skilled clinician. Nerve conductions tests are also helpful for confirmation.
The initial treatment may consist of splinting as well as anti-inflammatory medications. Rest- staying away from keyboard work if this is what welcomed it on in the first place – is mandatory.
If symptoms persist, then a corticosteroid injection into the carpal tunnel using ultrasound needle guidance is a good option. Data indicates that this procedure may be very helpful in alleviating the symptoms. In the past, patients who did not respond to injection and splinting were probably considered candidates for surgery.
A new technique may make this approach obsolete.
Percutaneous needle release using ultrasound guidance is a minimally invasive approach. Using local anesthetic with ultrasound guidance, a small needle is inserted and fluid is injected at the same time to shred the fibers of the flexor retinaculum, the tough band of tissue that forms the roof of the carpal tunnel. With repeated movements of the needle and further hydrodissection with fluid, the retinaculum weakens and the physician is able to gently break the retinaculum. A splint is applied and the patient is back to normal activities the next day.