Mini-midvastus versus mini-medial parapatellar approach in total knee arthroplasty: a prospective, randomized study

To date, no English literature has evaluated the short-term results of the mini-medial parapatellar approach compared with the mini-midvastus approach. This prospective, randomized study was performed to compare the short-term results of total knee arthroplasty using either a mini-midvastus or a mini-medial parapatellar approach.

We reported the clinical and radiological results of 89 patients who had primary total knee arthroplasties with minimally invasive techniques using either a mini-midvastus or a mini-medial parapatellar approach. The mini-midvastus approach was used on 45 patients (group I) and a mini-medial parapatellar approach on 44 patients (group II). Skin incision length, tourniquet time, incidence of lateral retinacular release, total blood loss, straight leg raising time, visual analogy scale score, alignment of the knee, component position, and complication of each group were examined. Knee Society scores, range of motion were compared at 7 days, 6 weeks, 3 months, and 6 months postoperatively.

The mean tourniquet time was 68 min in group I, significantly longer than 56 min for group II. However, comparisons of postoperative knee scores and function scores between both approaches did not yield a significant difference in outcome. No significant difference was found with respect to total blood loss, visual analogy scale score, straight-leg-raising test, range of motion or radiographic findings.

Based on these results, we believe that the early results are similar between mini-midvastus and mini-medial parapatellar approach, ultimately the selection of the surgical approach will depend on the surgeon's experience and preference.