Currently, we prefer the term tendinosis to epicondylitis as this is more descriptive of the true pathology (1). Epicondylitis (tendinosis) occurs at least five times more commonly on the lateral than on the medial aspect of the joint. The selection factors to determine the candidates for surgery are similar for each process, yet there are some distinct features with regard to the surgical technique (2). Thus, medial epicondylitis is discussed separately in Chapter 25.

Physical findings include local tenderness to palpation over the tendon origin at the epicondyle. Provocative tests of pain with resisted wrist extension for lateral involvement are invariably positive especially with the elbow in full extension. In some cases, the symptoms may be aggravated by performing the test with the elbow in 90-degree flexion (a sign indicating substantial tendinosis) (4,6). If forearm pain is a component (unusual), examine for posterior interosseous nerve irritation (an independent malady) (7). The most sensitive test is pain on resistive supination (8).

The most commonly involved tissue, the pathologic process, and the principles of the surgical intervention should be reviewed prior to undertaking the surgical procedure (9).

The hallmarks of good surgical concept and technique include precise identification of the pathologic tissue, resection of all involved pathology, maintenance of normal tissue attachments, protection of normal tissue, enhancement of vascular supply, firm repair of the operative site, and quality postoperative rehabilitation.

Kraushaar and Nirschl (1) have now defined the histopathology in precise detail utilizing the methods of electron microscopy and a histoimmunochemistry. The ECRB (100%) and the extensor communis (anterior edge) are the tissues most commonly involved laterally (100% and approximately 35%, respectively) (10,11,12 and 13). Histologically, the pathologic tissue is devoid of inflammatory cells but has a characteristic pattern of immature fibroblasts and vascular elements (1,14). Recent electron microscopic evidence reveals lack of extracellular cross-linkage (1). Current recommended technique specifically focuses on demonstrated pathoanatomy. It should be noted that although the classical case, in our experience, is angiofibroblastic tendinosis in the ECRB, the anteromedial edge of the EDC origin has concomitant pathology in 35% of cases and, when present, should be addressed. Additional pathologies include bony exostosis of the lateral epicondyle in 20% of cases and anterolateral compartment intra-articular pathology such as synovitis, plica, and chondromalacia (5%) (9).

Intra-articular changes as noted above have also been observed with the advent of elbow arthroscopy as a therapeutic tool (Fig. 24-1). Today, we specifically assess by clinical exam and imaging studies the possibility of any symptom-producing intra-articular element (5% in our experience) and proceed accordingly with possible arthroscopy or limited arthrotomy in such cases (3,15,16).

The described technique and illustrations apply for the large majority of cases. It should be noted, however, that individual variations can and do occur. In these instances, the pathologic variations should be addressed as presented.