Issue link: https://www.massageandbodyworkdigital.com/i/1315831
82 m a s s a g e & b o d y wo r k j a n u a r y/ fe b r u a r y 2 0 2 1 Tendon Pathologies in the Wrist and Forearm BY WHITNEY LOWE The tendons of the distal upper extremity muscles must be able to freely slide within the synovial sheath. Repetitive overuse or other factors may lead to an inflammatory irritation between the tendon and surrounding synovial sheath. Adhesions can also develop as a result. The inflammatory reaction along with potential connective tissue adhesion is tenosynovitis. De Quervain's Tenosynovitis De Quervain's tenosynovitis is more common, and thus more well known, than intersection syndrome. There are two tendons involved in this condition: abductor pollicis longus (APL) and extensor pollicis brevis (EPB). Both tendons course under a retinaculum near the styloid process of the radius in an area sometimes referred to as the anatomical snuff box (Image 2). Wrist and distal forearm pain complaints from overuse are increasingly common. As massage therapists, we grapple with these problems ourselves, and sometimes they can be career-ending injuries. Certain soft- tissue disorders, like carpal tunnel syndrome, are well known. Yet, there are other conditions—especially those affecting the tendons of the wrist and forearm region— that can produce chronic long-term pain as well. In this issue, we'll take a look at two key chronic overuse tendon disorders of the wrist and distal forearm—de Quervain's tenosynovitis and intersection syndrome. THE PATHOLOGY The most common terms we hear related to overuse tendon pathology are tendinitis or tendinosis, which result from collagen degeneration in the tendon. Both de Quervain's and intersection syndrome involve tenosynovitis, which is different in that it involves the synovial sheath surrounding certain tendons (the distal upper extremity in this case) (Image 1). The Synovial Sheath The purpose of the synovial sheath is to reduce friction between the tendon and a close adjacent structure, such as a binding retinaculum. Most tendons do not have a synovial sheath, however. The most common locations to find these sheathed tendons are in the distal upper and lower extremities where the tendons cross multiple joints. 1 Synovial sheaths in the upper extremity. Image from 3D4Medical's Complete Anatomy application. technique | CLINICAL EXPLORATIONS Repetitive overuse of the APL and EPB tendons is common in many occupations and recreational activities. During repetitive use, the tendons may rub against the retinaculum and cause the inflammatory reaction. In some cases, there can be a septum (a small connective tissue wall or divider) between the two tendons as they pass under the retinaculum. Friction against the wall of the septum can also lead to the tenosynovitis. Intersection Syndrome Intersection syndrome involves the two tendons also associated with de Quervain's tenosynovitis—the APL and EPB. Tendons in the distal upper extremity are divided into compartments that have connective tissue walls between them. The APL and EPB tendons are enclosed in the first dorsal compartment.