Abstract: BACKGROUND: Relevant studies have shown that anterior cruciate ligament rupture may be related to the anatomical morphology of the distal femur and proximal tibia.  
OBJECTIVE: To investigate the correlation between anterior cruciate ligament rupture and the match between the tibial intercondylar eminence and the femoral intercondylar fossa.
METHODS:  A total of 74 male soldier patients who were admitted at the 904 Hospital of the Joint Logistics Support Force from January 2016 to March 2021 and suffered unilateral knee injuries or discomfort due to non-contact mechanism were selected. According to X-ray and magnetic resonance imaging findings, they were divided into two groups (n=37 per group): an anterior cruciate ligament rupture group and an intact anterior cruciate ligament group. Width index of the intercondylar fossa was detected using coronal magnetic resonance imaging, and the morphology of the intercondylar fossa was observed using axial magnetic resonance imaging. In X-ray, posteroanterior films were used to detect the width, lateral and medial height of the tibial intercondylar eminence. Ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa was used to describe the match between the tibial intercondylar eminence and the femoral intercondylar fossa.  
RESULTS AND CONCLUSION: There was no significant difference between the two groups in the width of femoral bicondyle, the lateral and medial heights of the tibial intercondylar eminence (P > 0.05). The width of the intercondylar fossa, the width index of the intercondylar fossa, the width of the tibial intercondylar eminence, and the ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa in the anterior cruciate ligament rupture group was lower than that in the intact anterior cruciate ligament group (P < 0.05). The A-shaped intercondylar fossa was more common in the anterior cruciate ligament rupture group, and the U-shaped intercondylar fossa was more common in the intact anterior cruciate ligament group. Univariate Logistic regression analysis showed that the width of the intercondylar fossa, the width index of the intercondylar fossa, the morphology of the intercondylar fossa, the parameters of the tibial intercondylar eminence, and the ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa were all the influencing factors for anterior cruciate ligament rupture (P < 0.05). Multivariate Logistic regression analysis showed that the ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa was an independent risk factor for anterior cruciate ligament rupture (P < 0.05). Receiver operating characteristic curve showed that the ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa had a certain predictive value for anterior cruciate ligament rupture. To conclude, the ratio of the width of the tibial intercondylar eminence to the width of the intercondylar fossa is an independent risk factor for anterior cruciate ligament rupture. It has a certain predictive value for anterior cruciate ligament rupture. The worse the match between the tibial intercondylar eminence and the femoral intercondylar fossa is, the higher the risk of anterior cruciate ligament rupture is.

Key words: anterior cruciate ligament, intercondylar fossa, tibial intercondylar eminence, imaging, anatomy, width index of the intercondylar fossa, rupture of the anterior cruciate ligament