Tennis elbow (lateral epicondylar tendonitis)

A 20y old woman presents complaining of proximal forearm pain exacerbated by extension of the wrist against resistance with the elbow extended. She denies trauma but is an avid racquetball player. Which of the following is the most likely diagnosis?

• a.Lateral epicondylar tendonitis
• b.Medial epicondylar tendonitis
• c.Olecranon bursitis
• d.Biceps tendinitis
• e.Long thoracic nerve early paralysis

The answer is (a).

Tennis elbow or lateral epicondylar tendonitis is most commonly characterized by tenderness of the common extensor muscles at their origin (the lateral epicondyle of the humerus). Passive flexion of the fingers and wrist and having the patient extend the wrist against resistance causes pain.

Golfer’s elbow or medial epicondylar tendonitis is a similar disorder of the common flexor muscle group at its origin, the medial epicondyle of the humerus. Olecranon bursitis is an inflammation of the bursa over the olecranon process caused by acute or chronic trauma (“student’s elbow”) or secondary to gout, rheumatoid arthritis, or infection. Clinically, there is swelling or pain upon palpation of the posterior elbow. Paralysis of the serratus anterior muscle (innervated by the long thoracic nerve) causes the scapula to protrude posteriorly from the posterior thoracic wall when the patient is asked to push against a wall (winged scapula).