Intercondylar notch width and the risk for anterior cruciate ligament rupture in the osteoarthritic knee: evaluation by plain radiography and CT scan.

We measured the intercondylar notch morphometrically from radiographs and CT scans of 30 osteoarthritic knees. Our purpose was to assess the accuracy of the standing posteroanterior 30 degrees flexion view in determining whether there is a critical notch width that might predict a higher risk for rupture of the anterior cruciate ligament due to osteophytes. A correlation was found between measurements made on radiographs and CT scans and the appearance of the anterior cruciate ligament at operation. A narrow notch (less than 12 mm wide) was associated with absence of the anterior cruciate ligament.