Minimally Invasive versus Standard Approach in Total Knee Arthroplasty

We compared a group of 20 patients who had 24 minimally invasive total knee arthroplasties with a similar group of 21 patients who had 25 standard medial parapatellar approach total knee arthroplasties. We wanted to clarify whether the minimally invasive group had an advantage over the standard group in muscle strength, pain level, postoperative recovery, and clinical results and whether the patients were prone to radiographically poor results, more operative time, and increased complications. The extensor and flexor torque, visual analog scale, pace of rehabilitation, Knee Society scores, radiographic findings, operative time, and complications of each group were examined. The minimally invasive group showed higher extensor torque values, higher ratios of postoperative to preoperative extensor torque, and lower average visual analog scale scores at 1 and 2 weeks. The patients in this group achieved straight leg raising, 90° knee flexion, and T-cane gait earlier. There was no component malalignment, but the tibial component shifted to a more medial position. The mean operative time was 56 minutes longer in the minimally invasive group. We encountered no major perioperative complications in either group. We believe the minimally invasive technique positively contributes to the early restoration of quadriceps strength and a speedy return to normal function.

Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.