The carpal tunnel is a narrow area at the base of the hand that serves as a conduit for the median nerve that provides sensations in the thumb, index and middle fingers, and part of the ring finger. Carpal tunnel syndrome is a nerve entrapment syndrome that occurs when this tunnel become irritated, inflamed or injured, squeezing or compressing the nerve as it passes through the tunnel. It’s most commonly associated with repetitive movements that rely on the fingers, hands, and wrists. Carpal tunnel syndrome causes symptoms like pain, numbness and tingling in the fingers and hand, and over time, it can also affect grip strength and fine motor skills.
Diagnosis begins with a review of symptoms and a physical examination of the wrist, hand and lower arm, including range-of-motion exercises to help pinpoint the cause of symptoms. Nerve studies can also be used to confirm a diagnosis, and more recently, ultrasound evaluations have proven useful in assessing the nerve and the soft tissues surrounding it. Ultrasound evaluations take less than a half hour to perform, and they’re done right in the office using a special handheld device or transducer that’s held against the skin over the wrist. The transducer emits ultrasound waves which bounce off the interior structures of the wrist, returning data to the ultrasound machine which creates detailed images of the wrist anatomy.
Steroids are medicines used to help reduce inflammation so pressure on the median nerve is relieved. Injections are usually reserved for patients in whom other methods like splinting or oral pain medicines have failed to provide relief. Injections are performed in the office and take less than a half hour. First, the injection site is carefully cleansed and a local anesthetic will be used to numb the area. Next, the steroid medication is injected into the carpal tunnel space. Once the injection is complete, a small bandage will be placed over the injection site. Steroid injections may be helpful in enabling some patients to avoid the need for wrist surgery, and it can also be useful in predicting the success of surgery since patients who find temporary relief from steroid injections tend to achieve good outcomes from surgery.