When the median nerve is trapped within the carpal tunnel (or by shortening in the pronator teres muscle, ie. “pronator syndrome”), there can be tingling, numbness, impaired sensation, and the pain in the median-nerve-supplied first three fingers and thumb. The symptoms may be reproduced by forced flexion at the wrist, maintained for 2 minutes.
In early cases, before severe muscle wasting occurs in the thenar muscles, the condition responds to needling of the median-supplied muscles in the forearm (pronator teres and quadratus, and the wrist and finger flexors) and the thenar muscles (abductor pollicis brevis, opponens pollicis, and flexor pollicis brevis). More often than not, there is “double entrapment” and nerve roots at the cervical spine also require release by needling paraspinal muscles. In advanced cases, when there has been denervation, results are poor even with surgery.