Locking plate fixation compared with tension-band wiring for patellar fractures: a multicentre randomized controlled trial

Aims: Patellar fractures are associated with considerable postoperative morbidity, and tension-band wiring has high complication rates and suboptimal outcomes. Locking plate fixation is a recent surgical innovation which confers superior biomechanical stability. However, there is little information about the clinical outcomes of this method of treatment. The aim of this study was to compare locking plate fixation with tension-band wiring in patients requiring surgical treatment for a patellar fracture. Methods: In this patient- and assessor-blinded, multicentre randomized trial, 122 adults with a displaced patellar fracture were assigned 1:1 to locking plate fixation or tension-band wiring. The primary outcome was patient-reported knee function measured by the five sub-scales of the Knee Injury and Osteoarthritis Outcome Score (KOOS) at 12 months. Superiority was predefined as a statistically significant difference in at least three KOOS sub-scales exceeding the minimal clinically important difference (pain 10, symptoms 9, activities of daily living 6, sport and recreation 10, quality of life 10). Secondary outcomes included additional clinical and functional outcomes. Analyses were performed according to the intention-to-treat principle. Results: A total of 63 patients were assigned to locking plate fixation and 59 to tension-band wiring; 57 (90.5%) and 52 (88.1%), respectively, completed 12-month follow-up. Locking plate fixation resulted in statistically significant and clinically meaningful improvements in three KOOS sub-scales at this time: symptoms (mean difference -10.4 (95% CI -16.4 to -4.4)), sport and recreation (-14.1 (95% CI -24.7 to -3.4)), and quality of life (-10.9 (95% CI -19.0 to -2.7)). Removal of hardware, failure of fixation, and reoperation occurred more frequently after tension-band wiring. Conclusion: Locking plate fixation yielded superior patient-reported outcomes compared with tension-band wiring at 12 months, providing high-level evidence supporting the use of plate fixation as a preferred surgical technique for patients with a displaced patellar fracture.