Tailored tibial tubercle transfer for patellofemoral malalignment: analysis of clinical outcomes

Abstract

The purpose of this study was to describe the surgical technique, and evaluate and analyze the clinical outcomes of patients who underwent tibial tubercle realignment in our institution. Reported results of tibial tubercle transfer for patellofemoral malalignment vary considerably. Most authors rely mainly on the passive intraoperative patellar tracking test in determining the new location of the tibial tubercle. Conversely, the senior author relocates the tibial tubercle based on the intraoperative active and passive patellar tracking tests and the condition of the patellar articular surface. The medical records of 66 consecutive patients who underwent 80 tibial tubercle relocation procedures due to patellar instability or patellofemoral pain and maltracking were reviewed. Fifty-five patients with 69 operated knees participated in designated follow-ups which were conducted according to a predesigned protocol. The median follow-up was 6.2 years (range 2-13 years). Clinical outcomes significantly improved compared to the preoperative state; 72.5% of operated knees demonstrated good-to-excellent results according to the Lysholm and Karlsson scores, and physical findings supported the positive effect of the procedure. A statistically significant positive correlation was found between clinical outcomes and male gender, the absence of moderate to severe patellar chondral damage, and instability as the dominant preoperative symptom. Postoperative complication rate was low and patients with longer postoperative follow-ups demonstrated better clinical outcomes. The presented method of tibial tubercle transfer provided a good long-lasting surgical solution for patients with patellar instability and patients with patellar maltracking and anterior knee pain. Good prognostic factors included male gender, clinical patellar instability as the dominant preoperative symptom and intact patellar articular cartilage.