The Effect of Patella Eversion on Clinical Outcome Measures in Simultaneous Bilateral Total Knee Arthroplasty: A Prospective Randomized Controlled Trial

Abstract Background During total knee arthroplasty (TKA), surgical exposure requires mobilization technique of the patella. With this trial, we intended to investigate the effect of patella eversion on clinical outcome measures in simultaneous bilateral TKA. Methods We prospectively enrolled 44 patients (88 knees) from April 2008 to June 20l4.One knee was operated with patella eversion (group A) and the other with patella lateral retraction (group B) randomly. Follow-up results, including the operation time, complications, and the time of achieving straight leg raise (SLR) and 90° knee flexion, were recorded. The data of range of motion (ROM) and Visual Analogue Scale score were collected separately at 7 days, 3 months, 6 months, and 1 year postoperatively. Results The time of achieving SLR was 2.7 ± 0.8 days in group A and 2.1 ± 0.7 DAYS in group B, which were significantly different ( P = .032). Significant difference was found on active and passive ROM during the follow-up times between groups A and B, except the passive ROM at 6 months postoperatively. No significant difference was found on operation time, complications, patella baja or tilt, time of achieving 90°knee flexion, and Visual Analogue Scale score during the follow-up times. Conclusions Patellar eversion was adverse to the early knee function recovery after TKA; it would delay the time of achieving SLR and decrease the passive and active ROM. In addition, more carefully and scientifically designed randomized controlled trials are still required to further prove the claim.