Tennis elbow: blending basic science with clinical practice.

Tennis elbow defines a condition of varying degrees of pain or point tenderness on or near the lateral epicondyle. It is prevalent in individuals who perform a combination of forceful and repetitive activities including athletes and wheelchair users. The most common work-related disorder at the elbow is tennis elbow. Histopathological findings indicate that tennis elbow is a degenerative condition, called tendinosis, of the common extensor tendon, with the extensor carpi radialis brevis tendon more commonly implicated as the primary location of tendinosis. Despite the absence of inflammation, patients with tennis elbow still present with pain. Neurochemicals including glutamate, substance P, and calcitonin gene-related peptide have been identified in patients with chronic tennis elbow and in animal models of tendinopathy. Their presence provides an alternative mechanism for pain mediation. Based on what is known about tissue changes within chronic tendinopathies, implications for therapy including examination and interventions are discussed.