Midvastus Versus Medial Parapatellar Approach in Simultaneous Bilateral Total Knee Arthroplasty

The purpose of this study was to compare the postoperative outcomes over a period of 3 years in patients who underwent bilateral total knee arthroplasty (TKA) using midvastus (MV) versus medial parapatellar (MPP) approaches.

In this retrospective study, 2 propensity-matched cohorts of patients who underwent simultaneous bilateral TKA via MV (n = 100) and MPP (n = 100) approaches from January 2017 to December 2018 were compared. Surgical parameters compared were surgery time and the incidence of lateral retinacular release (LRR). Clinical parameters including the visual analog score for pain, time for straight leg raise (SLR), range of motion, the Knee Society Score, and the Feller patellar score were assessed in the early postoperative and follow-up periods up to 3 years. Radiographs were evaluated for alignment, patellar tilt, and displacement.

LRR was performed on 17 knees (8.5%) in the MPP group and 4 knees (2%) in the MV group which was significant (P = .03). The time to SLR was significantly lower in the MV group. There was no statistically significant difference in the length of hospital stay between the groups. The visual analog score, range of motion, and Knee Society Score were better in the MV group within 1 month (P < .05), but no statistically significant differences were found later. Patellar scores, radiographic patellar tilt, and displacements were similar at all follow-up periods.

In our study, the MV approach had faster SLR, less LRR, and better pain and function scores in the first few weeks after TKA. However, its effect on different patient outcomes has not been sustained at 1 month and further follow-up points. We recommend that surgeons use the surgical approach with which they are most familiar.