Rotator cuff tear may have significance include os acromiale and acromial spurs. Environmental factors implicated include increasing age, shoulder overuse, smoking, and any medical condition that affects circulation or impairs the inflammatory and healing response, such as diabetes mellitus. Intrinsic factors refer to injury mechanisms that occur within the rotator cuff itself. The principal is a degenerative-microtrauma model, which supposes that age-related tendon damage compounded by chronic microtrauma results in partial tendon tears that then develop into full rotator cuff tears. As a result of repetitive microtrauma in the setting of a degenerative rotator cuff tendon, inflammatory mediators alter the local environment, and
Posterior compartment of the forearm De Quervain's syndrome is a medical condition when the synovial sheath surrounding tendons in the first extensor tendon compartment becomes inflamed, so called tenosynovitis. The tendons of the abductor pollicis longus and the extensor pollicis brevis run narrower due to the thickening of the synovial sheath, which causes pain when extending and moving the thumb outward. Carpal tunnel syndrome is a condition when the median nerve is compressed as it passes through the carpal tunnel, which causes pain, numbness and tingling. The presence of an additional tendon may result in a condition called fourth compartment syndrome. Supernumerary tendons are common