PURPOSE: Chronic acromioclavicular joint lesions are a common source of pain and disability in the shoulder. The goal of this study was to evaluate diagnostic values of physical tests for isolated, chronic acromioclavicular joint lesions. STUDY DESIGN: A retrospective case-control study. METHODS: Between 1994 and 2002, 35 patients underwent a distal clavicle excision for isolated acromioclavicular joint lesions. The results of 3 commonly used examinations for acromioclavicular joint lesions were calculated for sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy. RESULTS: The cross body adduction stress test showed the greatest sensitivity (77%), followed by the acromioclavicular resisted extension test (72%) and active compression test (41%). The active compression test had the greatest specificity (95%). All tests had a negative predictive value of greater than 94%, but the positive predictive value was less than 30% for all tests. The active compression test had the highest overall accuracy (92%), followed by the acromioclavicular resisted extension test (84%) and the cross arm adduction stress test (79%). Combinations of the tests increased the diagnostic values for chronic acromioclavicular joint lesions. CONCLUSIONS: These tests have utility in evaluating patients with acromioclavicular joint pathologic lesions, and a combination of these physical tests is more helpful than isolated tests.