Abnormal femoral trochlea morphology is a risk factor for secondary injury of anterior cruciate ligament after reconstruction.

Secondary injury of the anterior cruciate ligament (ACL) is a common concern after anterior cruciate ligament (ACL) reconstruction, and identification of morphological risk factors is essential to prevent these injuries. We hypothesized that abnormal femoral trochlea morphology is associated with secondary ACL injuries after reconstruction. This study aimed to investigate the relationship between femoral trochlear morphology and secondary ACL injuries after reconstruction. A retrospective analysis was conducted on 20 patients who experienced secondary ACL injuries after reconstruction in our hospital between 2017 and 2022 (experimental group), and 40 patients were included in the control group. The following femoral trochlear characteristics were compared between the 2 groups: medial condylar height (MCH), trochlear sulcus height (TSH), lateral condylar height (LCH), trochlear sulcus depth (TSD), trochlear sulcus angle (TSA), medial trochlear inclination (MTI), and lateral trochlear inclination (LTI). The study found that patients in the secondary ACL injury after reconstruction group exhibited the following differences when compared to the control group: decreased MCH (56.33 ±â€…3.52 vs 59.93 ±â€…3.24, P value = .015), decreased TSD (4.89 ±â€…1.56 vs 6.98 ±â€…1.23, P value ˂ .001), decreased MTI (12.54 ±â€…6.57 vs 19.45 ±â€…6.35, P value ˂ .001), and increased TSA (145.23 ±â€…9.76 vs 139.25 ±â€…8.42, P value ˂ .001). This study demonstrated a significant correlation between abnormal femoral trochlear morphological characteristics and secondary ACL injuries after reconstruction. Decreased MCH, TSD, and MTI along with increased TSA are associated with a higher risk of secondary ACL injury. These data could thus help identify individuals susceptible to secondary ACL injuries after reconstruction.