Navigation-assisted less invasive total knee arthroplasty compared with conventional total knee arthroplasty: a randomized prospective trial

The purpose of this study was to evaluate the hypothesis that a less invasive (LIS) surgical technique using a navigation system would promote rapid recovery and improve alignment compared with conventional technique in total knee arthroplasty (TKA). This study compared 49 navigation-assisted LIS TKAs with 53 conventionally performed TKAs using a medial parapatellar arthrotomy with patellar eversion. Navigation-assisted LIS TKA used a shorter skin incision, a midvastus approach without patella eversion, and a navigation system. Navigation-assisted LIS TKA had better pain scores, shorter times to achieve 90 degrees flexion and straight leg raise, and a smaller extension lag during the very early postoperative period. However, there were no differences between the groups 2 weeks postoperatively. There were no differences in mean prosthetic alignment between the 2 groups, but the navigation-assisted LIS group had fewer "outliers" than the conventionally performed TKA group.