In a prospective study, the accuracy of arthrography was compared to that of the anterior drawer sign in the diagnosis of anterior cruciate ligament tears. In 29 surgically proven cases, arthrography had a sensitivity of 91%, specificity of 89%, and predictive value of 83%. The anterior drawer sign had a sensitivity of 91%, specificity of 100%, and predictive value of 100%. Reasons for false-positive and false-negative arthrograms and drawer signs are discussed. Although arthrography is accurate in determining anterior cruciate abnormalities, it is no more reliable than the anterior drawer sign. Physical examination should remain the principal means of cruciate diagnosis.