Background
Tendonitis is an inflammatory condition characterized by pain at tendinous insertions into bone. The term tendinosis refers to the histopathologic finding of tendon degeneration. The term tendinopathy is a generic term used to describe a common clinical condition affecting the tendons, which causes pain, swelling, or impaired performance. Because of the fact that most pain from tendon conditions is not actually inflammatory in nature, tendinopathy may be a better term than tendonitis.
Common sites of tendinopathy include the following:
- Rotator cuff of the shoulder (ie, supraspinatus) and bicipital tendons
- Insertion of the wrist extensors (ie, lateral epicondylitis, tennis elbow) and flexors (ie, medial epicondylitis) at the elbow
- Patellar and popliteal tendons and iliotibial band at the knee
- Insertion of the posterior tibial tendon in the leg (ie, shin splints)
- Achilles tendon at the heel
Pathophysiology
Tendons transmit the forces of muscle to the skeleton. As such, they are subjected to repeated mechanical loads, which are felt to be a major causative factor in the development of tendinopathy. Pathologic findings include tendon inflammation, mucoid degeneration, and fibrinoid necrosis in tendons. Microtearing and proliferation of fibroblasts have also been reported. However, the exact pathogenesis of tendinopathy is unclear.
Epidemiology
Mortality/Morbidity
Chronic tendinopathy can lead to weakening of the tendon and subsequent rupture.
Age
Middle-aged adults are most susceptible to the development of tendinopathy.
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