The effect of the intercondylar notch width index on anterior cruciate ligament injuries: a study on groups with unilateral and bilateral ACL injury.

BACKGROUND To evaluate the relationship of the intercondylar notch width with unilateral and bilateral ACL injury by using MR images. MATERIAL AND METHODS The intercondylar notch width index was measured on the MR images of 18 patients with a bilateral ACL injury, 38 patients with a unilateral ACL injury and 53 healthy subjects with a normal ACL and the results of all groups were compared with each other. RESULTS The mean NWI values were 0,227 (±0.008) in bilateral injured; 0,245 (±0.009) in unilateral injured and 0,272 (±0.01) in control groups and 0,251(±0.01) in unaffected side of the unilateral group. There were statistically significant differences in intercondylar notch width index (NWI) values between all groups and there was a significant difference between the affected and the unaffected sides in group with unilateral ACL injury. A cutoff value of 0.25 for NWI gave an odds ratio of 26.5 for bilateral and 3.23 for unilateral ACL injuries. CONCLUSIONS The finding that NWI is significantly narrowed in patients with bilateral and unilateral ACL tears compared with the healthy controls suggest a relationship between a narrow NWI and an increased risk of ACL injury. The patients with a narrow NWI should also be screened contralaterally for assessment of ACL injury risk on the other knee. So, specialized training programmes for the people with narrow NWI can be prepared for preventing ACL injuries.