Risk factors for noncontact anterior cruciate ligament injury: Analysis of parameters in proximal tibia using anteroposterior radiography

OBJECTIVE: To investigate the relationship between the proximal tibial parameters of tibia width (TW), eminence width (EW), and eminence width index (EWI), and noncontact anterior cruciate ligament (ACL) injury, in a Chinese population. METHODS: A retrospective case–control study was conducted of all ACL reconstructions (ACL group) and meniscal surgeries (control group) undertaken at two Chinese hospitals. Patients in the ACL group were age- and sex-matched with controls. Anteroposterior knee radiographs were used to measure the TW, EW and EWI. RESULTS: A total of 73 pairs of patients who were verified by knee arthroscopy, magnetic resonance imaging and physical examination were included in the study. There was no significant difference between the ACL group and the control group in terms of TW in the total population and in the two sex subgroups. The ACL group had a significantly smaller EW and EWI compared with the control group in the total population and in the two sex subgroups. CONCLUSION: Decreased EW and EWI are associated with increased risk of noncontact ACL injury in a Chinese population.