The Clinical Study Of Anatomic MPFL Reconstruction Combined With Lateral Retinaculum Release For The Treatment Of Acute Patellar Dislocation In Adolescents

Acute patellar dislocation is clinically common in knee joint,and the incidence is different in different groups.Adolescent population,manual workers and athletes with high strength,women with heavy height and weight,have higher risk of dislocation.In recent years,with the rapid development of the economy and the improvement of national fitness and competitive sports intensity,the incidence of the disease has gradually increased.Most of the studies at home and abroad focused on adults,while adolescents and adults have different degrees of joint injury,surgical methods and prognosis due to different anatomical structures and developmental problems.Conservative treatment was advocated after the first time,while it is possible to avoid the operation affect the risk of bone growth and development,to reduce the economic burden,but the problems appeared gradually.The recurrence rate is high,and a series of complications such as synovial hypertrophy,joint loose bodies,patella cartilage softening and patella-femoral arthritis.In recent years,with the development of the arthroscopic technique and magnetic resonance imaging used widely,the clinician gradually have a more thorough understanding of acute patellar dislocation in adolescents,and there is a new trend of early surgical intervention,the operation methods vary with different people,but due to the problem of sample size and short cycle of follow-up,there is no unified and effective guidance.In this study,we evaluated the clinical effect of MPFL anatomical reconstruction combined with lateral retinaculum release in the treatment of adolescent APD through knee examination,knee joint function evaluation,patella-femoral index and patellar inclination angle measurement.Objective:To investigate the clinical effect of anatomical medial patella-femoral ligament?MPFL?reconstruction combined with lateral retinaculum release?LRR?in the treatment of acute patellar dislocation?APD?in adolescents.Methods:Retrospective study,from March 2014 to September 2017,23 patients?23 knees?with adolescent acute patellar dislocation who underwent MPFL anatomical reconstruction combined with release of lateral retinaculum in the2^nd Department of Orthopaedics in Chengde Central Hospital were randomly selected as the observation group,all the surgeries were performed by a veteran surgeon who has been engaged in arthroscopic surgery for a long time.A total of 23 cases?23 knees?of adolescent with acute patellar dislocation were randomly selected as the routine group.Patients in both groups were followed up regularly,with an average of?14.34±8.65?months.The follow-up included:1.Physical examination of the knee joint:Patella Fear Test?PFT?,Patella Outside-push Test?POT?,Patella Inside-push Test?PIT?and Patella Tilt Test?PTT?.2.Lysholm Knee Scoring Scale and International Knee Documentation Committee?IKDC?2000 Scoring Scale were used to evaluate the knee function.3.Imaging examination:frontal and lateral radiographs of the knee,axial radiographs of the patella,plain CT scan of the knee and volume render?VR?are helpful for the preoperative and postoperative comparative evaluation of acute patellar dislocation.The indexes closely related to this study measured by imaging data:patella-femoral index and patellar obliquity angle.The patella-femoral index is defined as the ratio of the medial to the lateral gap of the superior patellar-femoral joint surface of the patellar axial image,with a normal value<1.6.The patella inclination angle refers to the overlap between the scanning plane of the maximum transverse diameter of patella in plain CT scan of the knee joint and the scanning plane of"Roman Arch Shape"on the top of the inter-condylar fossa.The connecting line of the posterior femoral condyle is used as the reference line to mark the straight line passing the transverse axis of patella.The included angle of the two straight lines is the patella inclination Angle.Both of them are larger than the normal value after acute patellar dislocation,and they both return to the normal range after operation,so it is of great significance.In addition,MRI plays an important role in determining the site and extent of MPFL injury and the prognosis of anatomical reconstruction of MPFL.The purpose of this study was to evaluate the clinical effect of anatomic MPFL reconstruction combined with lateral retinaculum release in the treatment of acute patellar dislocation in adolescents by observing the above special physical examination,knee function evaluation and important imaging data.Results:1.Comparison of basic information of observation and routine groupThere was no significant difference between the two groups in terms of gender,age,injury and time to treatment?P=0.830?0.980?1.000?.?Table1?2.Comparison of criteriaIn the physical examination,there were no statistically significant differences between the two groups in PFT?POT?PIT and PTT?P=0.264?0.310?0.310?0.197?.However,compared with the preoperative,there were significant differences between the two groups,and the observation group was more significant than the conventional group.?Table 2?In terms of joint function evaluation,there was no statistical difference in Lysholm score and IKDC2000 score between the two groups before treatment?P=0.437?0.682?.There were statistical differences between the two groups in the last follow-up?P=0.021,0.014?.?Table 3?In terms of imaging measurement and evaluation,there was no statistical difference in patella-femoral index and patella-femoral inclination angle between the two groups before treatment?P=0.835?0.537?.After treatment,there were statistical differences between the two groups in the last follow-up?P=0.011,0.013?.?Table 4?In terms of the overall evaluation of the treatment effect and the recurrence rate of patellar dislocation,there was a statistical difference between the two groups?P=0.012?.?Table 5?Conclusion:The anatomic reconstruction of MPFL combined with the lateral retinaculum release in the treatment of acute patellar dislocation in adolescents has a satisfactory clinical effect,which can effectively improve the treatment efficiency and reduce the recurrence rate of patellar dislocation.