Jordy van Sambeeck

Complications of a self-centering sliding tibial tubercle osteotomy for patellofemoral complaints 3 49 Figure 1. Surgical technique. A lateral osteotomy in the frontal plane is performed, about 5 cm long and 0.75 cm thick. Medial soft tissues remain intact to the tuberosity. Patellar height can then be adapted and the tibial tuberosity is fixed temporarily, then the knee is flexed tot 90 degrees. This centers the patella between the distal femoral condyles, causing the patella tendon to center the tibial tuberosity. In this position the tuberosity is fixed with two or three lag screws. Statistical analysis: A Chi-square test was used to detect differences in major and minor complications between sexes, whether or not patients had previous surgery, whether or not additional procedures were performed and between indications pain and instability. Fisher´s exact test was used if the observed value was 10 or lower or when expected count was equal to or lower than 5 with Chi-square analysis. If a complication occurred less than five times, no analysis was performed. Statistical analyses were performed using the statistical package SPSS 20.0 for WINDOWS (IBM SPSS, Chicago, IL, USA). Results Five hundred and twenty-nine (529) knees in four hundred and forty-seven (447) patients were included in analysis. Two patients with patellar dislocation after a prior TKA were excluded. Descriptive statistics are displayed in table 1.