Complication Rates Following Tibial Tubercle Osteotomy With and Without Distalization in Young Patients With Patellar Instability: A Multicenter Study.

Background: Tibial tubercle osteotomy (TTO) is a surgical procedure for the management of patellofemoral instability (PFI). Tubercle distalization requires a complete osteotomy detachment and has been shown to have an increased rate of certain complications in predominantly adult cohorts. With this study we identify and compare the complication rate of 2 TTO techniques-anteromedializing alone (AM) and anteromedializing with concomitant distalization (AMD) among young patients.

Methods: A retrospective comparative study was conducted from 2010 to 2021 at 2 large tertiary care pediatric hospitals identifying adolescent and young adult patients (<21 years) who presented for surgical treatment of PFI undergoing TTO. Groups were stratified based on the type of TTO: AM and AMD. Demographics and radiographic measures were recorded. Postoperative complications were identified and recorded using the modified Clavien-Dindo-Sink (CDS) classification system. Bivariate testing was conducted to compare variables among treatment groups.

Results: Seventy-six knees undergoing tubercle osteotomy (47 AM and 29 AMD) were identified. Treatment cohorts had similar demographics, mean preoperative CDI, Oswestry-Bristol classification, and Dejour classifications. Median follow-up was similar between both the groups in the AM and AMD groups (P=0.5). The overall complication was 22% (n=17/76) whereas in the AM group and AMD group was 19% (n=9/47) and 27% (n=8/29), respectively (P=0.57). The most common complications observed in both groups were infection and arthrofibrosis. No significant differences between AM and AMD groups were noted with respect to the grade of complication and individual complication rates (P >0.05).

Conclusion: The rate of overall complications was similar to prior adult studies. In this large adolescent cohort, tubercle distalization compared with anteromedial transfer alone did not demonstrate statistically significant differences. Findings from this study help surgeons understand complication rates and improving counselling among adolescent PFI patients being considering for a distalizing TTO.

Study design: Retrospective comparative study; level of evidence III.