Lateral Epicondylitis: Assessment and Rehabilitation

Lateral epicondylitis (LE) - commonly referred to as tennis elbow - is the most frequently diagnosed condition affecting the elbow. Tennis players often experience elbow pain, with 50% of players reporting pain. Of these cases, 80% relate to LE⁽¹⁾. Archers or shooters may also present with pain relating to the lateral epicondyle and the extensor tendon⁽²⁾. In addition, up to 17% of manual workers in industries requiring repetitive hand tasks commonly present with LE⁽¹⁾.

Lateral epicondylitis commonly affects people over 30 years of age and those pursuing activities requiring repetitive movements of the forearm. Pain may be aggravated by the gripping of small objects such as in racket sport-based movements, as well as painting and hammering. In 1936, Dr James Cyriax stated that the duration of symptoms for LE could typically last as long as six months and possibly up to two years. This is still true in the modern era; 50% of patients still present with LE related symptoms 12 months after presenting in clinical practice⁽¹⁾.

Anatomy and biomechanics

The primary structures involved in LE are the extensor carpi radialis brevis (ECRB), and less frequently, the extensor carpi radialis longus (ECRL)⁽²⁾. These structures originate at the lateral epicondyle of the distal humerus and attach via the extensor tendon (see Figure 1). The muscle tendon junction of the ECRB is in the mid forearm (where the tendon courses in conjunction with the ECRL) beneath the extensor retinaculum and inserts onto the lateral dorsal surface of the third metacarpal bone.

The ECRB is primarily a wrist extensor but also abducts the hand at the wrist joint. The ECRB is under greatest strain when its fibres contract whilst in forearm pronation coupled with wrist flexion and ulnar deviation. This is the position replicated during an incorrect back hand stroke in tennis, which explains the popular label of ‘tennis elbow’.

Efforts should be made to educate tennis players on techniques for correctly executing a backhand in tennis. It is often observed that a tennis player will use two hands to prevent overload to the wrist extensors. If a second hand isn’t used as support and the arm is straight (see Figure 2), the loading on the extensor tendon when the ball impacts the racquet can be very high. An alternative is to execute the shot with a flexed elbow where possible, to reduce this impact loading.