ABSTRACT
Objective:To investigate the related risk factors related to patellar dislocation combined with osteochondral fracture (OCF).Methods:A case control study was conducted to analyze the clinical data of 278 patients with patellar dislocation admitted to Second Hospital of Lanzhou University from January 2016 to June 2020, including 98 males and 180 females; aged 12-41 years [(21.1±4.6)years]. The patients were divided into OCF group ( n=112) and non-OCF group ( n=166) according to the surgical records and occurrence of OCF or not under intraoperative arthroscopy. The data of the two groups were recorded, including basic characteristics (ie, sex, age, sides of injury, whether or not the epiphysis is closed), patella height, patellar inclination angle, tibial tubercle-trochlear groove (TT-TG), femoral trochlear shape, tibial lateral rotation angle and femoral anteversion angle. Univariate analysis was adopted to evaluate the correlation of the data with patellar dislocation combined with OCF. Multivariate Logistic regression analysis was used to determine the independent risk factors of patellar dislocation combined with OCF. Results:Univariate analysis showed that patellar dislocation combined with OCF was related to male, patellar inclination angle and femoral anteversion angle ( P<0.05 or 0.01), while not to age, epiphysis is closed or not, sides of injury, patella height, TT-TG, femoral trochlear shape and tibial lateral rotation angle (all P>0.05). Multivariate Logistic regression analysis showed that male ( OR=1.75, 95% CI 1.07-2.90, P<0.05) and increased femoral anteversion angle ( OR=3.12, 95% CI 1.89-5.17, P<0.05) were significantly correlated with patellar dislocation combined with OCF. Conclusion:Male and increased femoral anteversion angle are independent risk factors for patellar dislocation combined with OCF.