Effect Of Arthroscopic Release Of Lateral Patellar Retinaculum On Early And Middle Stage Osteoarthritis Of Knee With Patellar Extraversion

Objective:To evaluate the effect of arthroscopic release of lateral patellar retinaculum on early and middle stage osteoarthritis of knee with patellar extraversion by comparing the progress of cartilage degeneration of patellofemoral joint and tibiofemoral joint before and after operation with the rehabilitation of clinical symptoms and functions of knee joint.Methods:158 patients with knee osteoarthritis in the early and middle stage were selected for arthroscopic release of lateral patellar retinaculum and postoperative functional exercise.According to the difference of patellofemoral index,it can be divided into three types: under correction type,acceptable correction type and over correction type.The clinical symptoms and functional recovery of knee joint before and after operation were compared,and the change of cartilage state was observed in MRI images.Results:There was no significant difference in age,gender,affected side,body mass index,mean follow-up time and interval time of MRI among all types of groups before operation(P<0.05);in clinical evaluation(Lysholm knee score;KOOS pain,symptoms,activities of daily life,sports / entertainment function and knee related quality of life;Shelbourne and trumper scores)and imaging evaluation(patellofemoral index,patella There was no significant difference in preoperative values between the two groups.The score of clinical and imaging results of knee joint after operation was higher than that before operation,difference between groups was statistically significant(P > 0.05);the incidence of chondrodegeneration of patellofemoral joint in under correction type was significantly higher than that in over correction type and acceptable correction type,but there was no difference between the two groups(patellofemoral joint: under correction type=64.1%,acceptable correction type=37.0%,over correction type=31.6%,P<0.05);tibiofemoral joint: under correction type=41.1% The acceptable correction type=39.0%,over correction type=36.8%,P > 0.05).The function of the uncorrected type [including Lysholm knee score,knee injury and Osteoarthritis Outcome Score(pain,symptoms and activities of daily life scale)and Shelbourne and trumper scores] was significantly worse.In all the patients,the clinical and imaging indexes were statistically significant(P<0.05),43.1% of patellofemoral joint and 39.2% of tibiofemoral joint cartilage degenerated in two years after operation.Conclusion:1.The patients with knee osteoarthritis in the early and middle stage with patellar extraversion can reduce the symptoms and improve the knee joint function,but the difference of patellar trajectory will still affect the knee joint.2.The release of lateral patellar retinaculum had no significant effect on the cartilage injury of tibiofemoral joint.3.Patellofemoral index can be used as a predictor of knee symptoms and functional.