Interexaminer reliability of three methods of combining test results to determine side of sacral restriction, sacral base position, and innominate bone position.

CONTEXT: Sacroiliac joint dysfunction is diagnosed based on the combined results of several palpatory examinations. Previous studies have compared the interexaminer reliability of only one of these methods of diagnosis.

OBJECTIVE: To compare the interexaminer reliability of three methods of combining palpatory examinations to determine the side of sacroiliac joint dysfunction, sacral base position, and innominate bone position.

DESIGN: Blinded single-cohort reliability study.

METHODS: Patients with low back pain underwent two identical sets of palpatory examinations given by two physicians, separately, at a university spine center. The results of each set were compiled and interpreted by three methods: using the test result with the highest interexaminer reliability (method 1), requiring at least one test result to be abnormal for the variable to be abnormal (method 2), and requiring all test results to be abnormal for the variable to be abnormal (method 3). The kappa was calculated for each method.

RESULTS: There were 24 subjects (mean age, 68.3 years), of which 15 (62%) were women. The kappa was consistently higher with method 1, at 0.47, 0.08, and 0.32 for the sacral position, innominate bone position, and side of sacroiliac joint dysfunction, respectively. Corresponding values for method 2 were 0.09, 0.4, and 0.16, and for method 3 were 0.16, 0.1, and -0.33.

CONCLUSION: Using the results of the most reliable examination consistently has the best interexaminer reliability.