The purpose of this study was to compare the measurements of the intercondylar notch width (NW) in men and women radiographically and intraoperatively, and to determine if the radiograph would demonstrate a difference in the patients with unilateral and bilateral anterior cruciate ligament (ACL) tears compared with non-injured patients. The control groups consisted of 100 men and 100 women from our young adult clinic population without a history of knee injury or clinical evidence of ligamentous deficiency. The study group consisted of 90 men with bilateral and 297 with unilateral ACL reconstructions (mean age 25.1 years, range 13-53 years) and 41 women with bilateral and 129 with unilateral ACL reconstructions (mean age 22.3 years, range 13-48 years). On 45 degrees flexion weight-bearing radiographs, we measured the intercondylar NW in controls and patients at one-half notch height from the lateral edge of the articular margin of the medial femoral condyle to the apex of the intercondylar notch. Intraoperatively, the surgeon took a direct measurement at the same site with sterile calipers. The surgeon was unaware of the radiographic measurement. The mean radiographic NW measurements for women were 12.8 mm in the bilateral group, 13.8 mm in the unilateral group, and 14.5 mm in the control group (P < 0.05) and, for men, 15.3 mm in the bilateral group, 15.8 mm in the unilateral group, and 16.9 mm in the control group (P < 0.05). The preoperative radiographic NW measurements correlated with actual intraoperative measurements (r = 0.72, P < 0.01). We conclude that the intercondylar NW of the femur is narrower in women than men, and, in both men and women, the NW is narrower in patients who sustain ACL tears compared with controls.