Failure of isolated medial patellofemoral ligament reconstruction in children: Risk factors and management

Abstract

Background: Patellofemoral instability is a frequent cause of referral in pediatric sports medicine. Isolated medial patellofemoral ligament reconstruction is widely used and provides satisfactory outcomes with a low failure rate. Given the success of this surgical technique, the literature on medial patellofemoral ligament reconstruction failures in the pediatric population is limited. Moreover, given the multifactorial nature of patellofemoral instability, the heterogeneity of the current literature, and the paucity of pediatric studies, medial patellofemoral ligament reconstruction failures are often difficult to analyze. Methods: The purpose of this study was to retrospectively review the associated risk factors, surgical management, and the clinical outcomes at 2-year follow-up of skeletally immature patients that presented to our clinic with a failed medial patellofemoral ligament reconstruction. Results: Of the 181 cases in 155 patients included in this study, treatment failed in 12 (7%). All 12 patients presented with at least one risk factor for patellofemoral instability, the most common being trochlear dysplasia and a high-grade J sign. Conclusions: We conclude that isolated medial patellofemoral ligament reconstruction for patellofemoral instability in children has a low failure rate. Clinicians must assess pre-operative risk factors before surgical treatment is considered. A high-grade J sign and high-grade trochlear dysplasia were associated with medial patellofemoral ligament reconstruction failure in this cohort. Tailoring treatment to patients’ associated risk factors selection may improve outcomes.

Concomitant anterior medializing osteotomy and MPFL reconstruction improves patellar tilt when compared to MPFL reconstruction alone

“…Recent studies have analyzed the outcomes of iMPFLR in various patient cohorts [1, 9, 12, 21, 30]. Shubin Stein et al found that regardless of bony pathologies, iMPFLR provides improved outcome scores and low rates of recurrence [9].…”

Simultaneous MPFL reconstruction and guided growth result in low rates of recurrent patellofemoral instability

“…Coronal plane angular deformities of the femur and tibia in children can lead to altered gait and limb length discrepancy. One underappreciated consequence of genu valgum is patellofemoral instability (PFI) as a result of an elevated Q angle and a resulting laterally directed vector acting on the patella as well as an increase of tibial tubercle-trochlear groove (TT-TG) measurements [1]. In adults, aside from traditional tibial tubercle osteotomy and/or medial patellofemoral ligament reconstruction (MPFL), corrective high tibial or distal femoral osteotomies are the only treatment of concomitant coronal malalignment for recurrent patellar dislocations [28].…”