The Kim test: A novel test for posteroinferior labral lesion of the shoulder - A comparison to the Jerk test

Background: Detection of a posteroinferior labral lesion by physical examination is often difficult. Purpose: To introduce a novel diagnostic test for detecting a posteroinferior labral lesion of the shoulder. Hypothesis: The Kim test can detect a posteroinferior labral lesion of the shoulder. Study Design: Cohort study (diagnosis); Level of evidence, 1. Methods: In 172 painful shoulders, the Kim test was compared with the jerk test and was verified by arthroscopic examination. A sudden onset of posterior shoulder pain and click with or without clunk indicated a positive test result. Results: Thirty-three shoulders had a positive Kim test result, in which 24 had a posteroinferior labral lesion and 9 had a normal posteroinferior labrum. Of 139 shoulders with a negative Kim test result, 6 had a posteroinferior labral tear and 133 had a normal posteroinferior labrum. The sensitivity of the Kim test was 80%, specificity was 94%, positive predictive value was 0.73, and negative predictive value was 0.96. The interexaminer reliability between 2 examiners was 0.91. The accuracy of the jerk test in detecting a posteroinferior labral lesion was the following: sensitivity, 73%; specificity, 98%; positive predictive value, 0.88; and negative predictive value, 0.95. The location of the posterior labral lesion was predominantly posterior in 19 shoulders and predominantly inferior in 11 shoulders. The Kim test was more sensitive in detecting a predominantly inferior labral lesion, whereas the jerk test was more sensitive in detecting a predominantly posterior labral lesion. The sensitivity in detecting a posteroinferior labral lesion increased to 97% when the 2 tests were combined. Conclusion: The Kim test is a reliable diagnostic test for detection of a posteroinferior labral lesion.