Quality-of-Life Outcomes of Patients following Patellofemoral Stabilization Surgery: The Influence of Trochlear Dysplasia

Abstract

AbstractTrochlear dysplasia is a well-described risk factor for recurrent patellofemoral instability. Despite its clear association with the incidence of patellofemoral instability, it is unclear whether the presence of high-grade trochlear dysplasia influences clinical outcome after patellofemoral stabilization. The purpose of this study was to assess whether trochlear dysplasia influenced patient-reported, disease-specific outcomes in surgically treated patellar instability patients, when risk factors were addressed in accordance with the à la carte surgical approach to the treatment of patellofemoral instability. The study design is of a case series. A total of 318 patellar stabilization procedures were performed during the study period. Of these procedures, 260 had adequate lateral radiographs and complete Banff Patellar Instability Instrument (BPII) scores available for assessment. A Pearson r correlation was calculated between four characteristics of trochlear dysplasia, the BPII total and the BPII symptoms, and physical complaints scores, a mean of 24 months following patellofemoral stabilization. Independent t-tests were performed between stratified trochlear dysplasia groups (no/low grade and high grade) and all BPII measures. There was a statistically significant correlation between measures of trochlear dysplasia and quality-of-life physical symptoms scores, an average of 2 years following patellofemoral stabilization surgery. The BPII symptoms and physical complaints domain score, as well as the individual weakness and stiffness questions, correlated with the classification of trochlear dysplasia as well as the presence of a trochlear bump (p < 0.05). Independent t-tests demonstrated statistically significant differences between the no/low-grade and high-grade dysplasia groups for the BPII stiffness (p = 0.002), BPII weakness (p = 0.05) and BPII symptom, and physical complaints values (p = 0.04). Two additional measures—the 24-month postoperative total BPII score (p = 0.11) and BPII pain score (p = 0.07)—demonstrated trends toward statistical significance. This research has established a statistically significant correlation between trochlear dysplasia and disease-specific quality-of-life outcomes following patellofemoral stabilization surgery. There was a significant correlation between patient-reported physical symptoms after surgery and high-grade trochlear dysplasia.