PARADOXICAL PHENOMENA OF THE MCMURRAY TEST - AN ARTHROSCOPIC INVESTIGATION

We evaluated 200 patients who had a positive McMurray test and found a typical McMurray test results in 24 patients (12%). These patients rev ealed pain or clicking or both either in the medial compartment of the knee when the leg was internally rotated or in the lateral compartmen t of the knee when the leg was externally rotated. The authors analyze d these paradoxical findings at arthroscopic examination to identify t he relationship between the type of meniscal tear and the direction of leg rotation that elicited the catching and displacement of the torn meniscal portion during the McMurray test. Contrary to conventional Mc Murray test findings, three different types of meniscal tears were fou nd on the side of the knee where pain or a clicking sound occurred. Th e three types were 1) anteriorly based posterior oblique tears with an terior displacement of the meniscus, 2) bucket-handle tears in the pos terior half of the menisci, and 3) peripheral detachment of discoid me nisci in the posterior half of the torn portions.