A Suprapatellar approach, when compared to an Infrapatellar approach, yields less Anterior Knee Pain and better patellofemoral joint Function, for intramedullary nailing of diaphyseal tibial fractures. Results of a Randomised Controlled Trial.

Abstract

OBJECTIVES: To assess if a suprapatellar (SP) approach, when compared to an infrapatellar (IP) approach, yielded less patient reported anterior knee pain and higher patellofemoral joint function at 6 weeks and 12 months post operatively, when treating tibial fractures with intramedullary nailing METHODS: Design: Prospective, parallel group randomized control trial Setting: Tertiary level one trauma care centre, Brisbane, Australia Patients Selection Criteria: Skeletally mature patients with an acute diaphyseal tibial fracture (AO/OTA 41A2/3, 42 A1- 43A3) amenable to an IMN were included. Exclusion criteria were peri-prosthetic fractures, nonunions, and presence of a contralateral injury that would restrict weightbearing. Outcome Measures and Comparisons: Anterior knee pain, through the visual analogue scale (VAS) and patellofemoral function using the Kujala scale at 6-weeks and 12-months were compared between those treated with a SP and IP approach. Results: 95 tibia fractures were included in the randomized trial, with complete follow-up data for 44 and 46 tibia fractures in the SP and IP groups, respectively. The SP cohort exhibited better patella-femoral knee function at both 6 weeks post operatively (Kajula 53.0 for SP vs 43.2 for IP, p<0.01)) and 12 months (Kujala 92.0 for SP vs 81.3 for IP (p<0.01)), and a reduction in anterior knee pain at 12-months post-operatively (VAS 0.7 SP vs 2.9 IP, p<0.01). Conclusions: This randomized trial demonstrated clinically meaningful differences in patellofemoral function, for a suprapatellar versus infrapatellar approach, with a greater than 10 point discrepancy in Kujala score at both 6 weeks and 12 months. Additionally, there was a clinically important difference in VAS knee pain scores for patients at 12 months, but not at 6 weeks, post operatively. These results contribute to the growing body of evidence demonstrating the functional and clinical benefits of the suprapatellar approach.