Mini-subvastus versus a Standard Approach in Total Knee Arthroplasty: A Prospective, Randomized, Controlled Study

This prospective randomized study compared the clinical and radiological results of primary total knee arthropasty (TKA) using a mini-subvastus approach (group I; n = 35) or a standard approach (group II; n = 33). A posterior-stabilized prosthesis was used in both groups by the same surgeon. Mean follow-up was 18 months (range 14 - 26 months). Patients in group I lost less blood and experienced less pain 1 day post-operatively. They achieved an active straight leg raise earlier and underwent less lateral retinacular releases. Functional outcome and the range of knee movements were significantly better in group I up to 9 months post-operatively, but there was no significant difference between the groups at 1 year post-operatively or at final follow-up. Reduced access and visibility in group I prolonged the operation time and resulted in five technical errors on radiographic evaluation. Based on these results, the authors currently only use the mini-subvastus approach for minimally invasive TKA in selected cases.