THE VALUE OF SONOGRAPHY IN THE DIAGNOSIS OF TRAUMATIC RUPTURE OF THE ANTERIOR CRUCIATE LIGAMENT OF THE KNEE

OBJECTIVE. The purpose of this study was to test the efficacy of sonog raphy in the diagnosis of rupture of the anterior cruciate ligament in the setting of a recent traumatic hemarthrosis. SUBJECTS AND METHODS. Sonography was prospectively performed in 37 patients with a recent t raumatic hemarthrosis of the knee, no bone abnormality seen on plain r adiographs, and no history of a previous knee injury, The presence of a hypoechoic collection along the lateral wall of the femoral intercon dylar notch was interpreted as a hematoma at the femoral attachment of the anterior cruciate ligament, Arthroscopy was subsequently performe d in 30 patients. The findings of three diagnostic techniques (sonogra phy, MR imaging, and arthroscopy) were compared, RESULTS. The sonograp hic findings were confirmed by MR imaging and arthroscopy in 34 of the 37 patients. For the three false-negative results, sonographic findin gs were abnormal but equivocal in two cases and were reported as negat ive, The technique was therefore 91% sensitive and 100% specific. The positive predictive Value was 100%. The negative predictive value was 63%. CONCLUSION. Sonography is a useful and inexpensive method of dete cting the presence of rupture of the anterior cruciate ligament in the clinical setting of a traumatic hemarthrosis.