The purpose of this study was to examine the interobserver concordance of the joint line tenderness (JLT) and McMurray tests, and to determine their diagnostic efficiency for the detection of meniscal lesions. The researchers conducted a prospective observational study at an orthopedics outpatient clinic in a university hospital with patients (N=60) with suspected nonacute meniscal lesions who underwent knee arthroscopy. Patients in the study were examined by 3 independent observers with graded levels of experience (>10y, 3y, and 4mo of practice). The interobserver concordance was assessed by Cohen-Fleiss κ statistics. Accuracy, negative and positive predictive values for prevalence 10% to 90%, positive (LR+) and negative (LR–) likelihood ratios, and the Bayesian posttest probability with a positive or negative result were also determined. The diagnostic value of the 2 tests combined was assessed by logistic regression. Arthroscopy was used as the reference test. No interobserver concordance was determined for the JLT. The McMurray test showed higher interobserver concordance, which improved when judgments by the less experienced examiner were thrown out. The whole series studied by the “best” examiner (experienced orthopedist) provided the following values: (1) JLT: sensitivity, 62.9%; specificity, 50%; LR+, 1.26; LR–, .74; (2) McMurray: sensitivity, 34.3%; specificity, 86.4%; LR+, 2.52; LR–, .76. The combination of the 2 tests did not offer advantages over the McMurray alone.
The study found that the JLT alone is of little clinical applicability. A negative McMurray test does not modify the pretest probability of a meniscal lesion, while a positive result has a fair predictive value. Therefore they concluded that in a patient with a suspected meniscal lesion, a positive McMurray test suggests that arthroscopy should be performed. In case of a negative result, further examinations, including imaging, are needed.