Which tests are commonly used to diagnose lateral epicondylitis?

• A. Mills test and Cozens sign
• B. Varus stress test and Valgus stress test
• C. Tinels sign and Wartenberg's test
• D. Pronator teres test and Mills test

Answer: (A)

Lateral epicondylitis is a tendinopathy of the common extensor tendon at the elbow, typically the extensor carpi radialis brevis, and the pain is reproduced when the tendon is stretched or loaded. The two tests most commonly used to diagnose this condition are Mills test and Cozen's sign.

Mills test works by placing the elbow in extension and then passively flexing the wrist. This action stretches the extensor tendons across the lateral epicondyle. If this stretch reproduces pain at the outer elbow, it strongly suggests lateral epicondylitis because the discomfort comes from the tendon insertion where overuse injures occur.

Cozen's sign involves the patient actively extending the wrist against resistance with the elbow straight and the forearm pronated (or the examiner resists wrist extension). This resisted load targets the same tendon complex as Mills test, and pain at the lateral epicondyle in this maneuver supports the diagnosis of lateral epicondylitis.

Other options test different structures: ligament stability with varus/valgus stress tests, ulnar nerve issues with Tinels sign and Wartenberg’s test, or median nerve entrapment with the pronator teres test. They do not specifically assess the extensor tendon origin responsible for lateral epicondylitis, which is why Mills test and Cozen's sign are the preferred diagnostic maneuvers.