Evaluation of risk correlation between recurrence of patellar dislocation and damage to the medial patellofemoral ligament in different sites caused by primary patellar dislocation by MRI: a meta-analysis

Abstract

Purpose Non-surgical treatment of primary patellar dislocation has a high risk of recurrent dislocation; thus, we tried to identify injuries in which sites of the medial patellofemoral ligament (MPFL) were most associated with recurrent dislocation by analyzing relevant original literature in order to provide improved suggestions on early surgical treatment. Methods According to the preset retrieval strategy, the original studies were retrieved until January 2020 using MEDLINE, Embase and Cochrane Library. Review Manager 5.3 software was used to summarize and compare the differences of recurrent dislocation of MPFL injuries at different attachments. Results Although the incidence of recurrent patellar dislocation at the femoral attachment of MPFL was higher overall (femoral only vs. patellar only vs. combined: 37.6% vs. 32.3% vs. 35.8%), no statistical difference was found among the three groups (femoral only vs. patellar only, RR = 1.32 [95% CI 0.89–1.95]; P = 0.17) (femoral only vs. combined, RR = 1.15 [95% CI 0.59–2.22]; P = 0.68) (patellar only vs. combined, RR = 0.94 [95% CI 0.69–1.29]; P = 0.72). In addition, the sulcus angle of recurrent dislocation group is significantly greater than that in the non-recurrent dislocation group (MD = 3.06 [95% CI 0.42–5.70]; P = 0.02). Conclusions Based on the pooled data collected from the original studies available, the risk of recurrent patellar dislocation due to damage to the MPFL at different sites did not differ. Additionally, the sulcus angle in the group with recurrent dislocation was considerably higher when comparing with the group without recurrent dislocation, that is, the shallower and flatter of the trochlear groove, the higher the risk of recurrent patellar dislocation.

Isolated medial patellofemoral ligament reconstruction for recurrent patellofemoral instability: analysis of outcomes and risk factors

“…The MPFL is the most important static restraint to the lateral displacement of the patella during the first 30° of flexion [ 76 ]. After the first patellar dislocation, the MPFL is always damaged [ 77 , 78 ] and a ligament reconstruction is often required [ 12 , 79 ]. Patients without imaging evidence of pathoanatomical risk factors are suitable for isolated MPFL reconstruction [ 80 – 83 ].…”

Surgical treatment of patellar dislocation: A network meta-analysis of randomized control trials and cohort studies

“…A study has shown elevated TT-TG distance, trochlear dysplasia, patella alta and so that 92% of 175 patients had MPFL injury after a first time acute patellar dislocation ( 11 ). Injured sites include the femoral attachment and the patellar attachment ( 12 ). Moreover, a biomechanical study showed that MPFL provides approximately 60% of the inward binding resistance against lateral patella displacement ( 13 ).…”

Neural Network Algorithm MRI Images for Analysis of Influencing Factors for Patellar Dislocation in Exercise

“…When the femur in motion is subject to internally rotated external force relative to the tibia, the inner surface of the patella bumps into the lateral femoral condyle, and the stress to cortical bone is transmitted to the bone trabecula, resulting in congestion, edema, and hemorrhage of trabecular bone. e different degrees of damage to the trabecular bone occurred due to external stress, and the patella was instantly separated from the trochlear groove, leading to patella dislocation [13][14][15]. e individual differences, and noise and artifacts in MRI images, and other interference factors [16,17], resulted in a certain probability of missed diagnosis in the diagnosis of clinical APD patients.…”