Lateral and Medial Epicondylitis of the Elbow

Abstract

In an austere letter published in Lancet in 1882, Henry J. Morris intro-duced a previously undescribed entity, which he aptly termed " lawn tennis arm. " From that seminal description has evolved a vast array of detailed diagnostic and therapeu-tic treatises on epicondylitis of the elbow. Morris focused on medial epicondylitis as caused by the lawn-tennis backstroke, but subsequent works have greatly expanded both the location and the etiology of this malady. Today, both medial and lat-eral epicondylitis are associated with a variety of sports activities and occupations. Lateral Epicondylitis Anatomy The musculotendinous structures about the lateral epicondyle of the elbow are those of the common extensor origin, including the exten-sor carpi radialis longus, the exten-sor carpi radialis brevis, the extensor digitorum communis, and the exten-sor carpi ulnaris. The extensor bre-vis, which is most commonly involved in lateral epicondylitis, lies beneath the extensor longus. The complex origin of the extensor bre-vis includes the common extensor tendon at the lateral epicondyle, the lateral collateral and annular liga-ments, the investing fascia, and the intermuscular septum.