The accuracy of diagnosis was tested in a prospective study of 145 patients who were arthroscoped because a meniscal tear was suspected clinically. Multiple variate analysis was used to evaluate 68 different clinical parameters. The clinical accuracy was 61% as a tear was demonstrated in 88 knees; 73 of these tears were associated with other intraarticular abnormalities. Thirteen knees were entirely normal at arthroscopy. It was possible to predict a meniscal tear in 8 out of 10 patients.