Comparison of mini-subvastus approach versus medial parapatellar approach in primary total knee arthroplasty

Minimally invasive knee arthroplasty is rapidly gaining recognition with the aim of reducing the damage to the extensional mechanism of traditional medial parapatellar approach and achieving faster recovery of patients after surgery. The purpose of this meta-analysis was to compare the efficacy and safety of mini-subvastus (MSV) and medial parapatellar (MMP) approach in primary total knee arthroplasty (TKA).

PubMed, EMBASE, the Cochrane Library, Web of Science and China National Knowledge Infrastructure and Google Search Engine were systematically searched for randomized controlled trials (RCTs) comparing mini-subvastus and medial parapatellar approach in primary TKA. Primary outcomes were total knee society score (KSS), functional KSS, straight leg-raising days. Secondary outcomes were hospital stays, blood loss, operation time, wound-related complications, deep venous thrombosis (DVT) and/or pulmonary embolism (PE). Subgroup analyzes were performed on the range of motion (ROM) at different follow-up times.

A total of 14 RCTs involving 1172 patients were included in the meta-analysis. No significant difference between the two groups was found in functional KSS (P = 0.31), hospital stays (P = 0.07), wound-related complications (P = 0.77), DVT (P = 0.59) and/or PE (P = 0.33). The MSV approach provides higher total KSS (P = 0.007), lower straight leg raising days (P = 0.003) and less blood loss (P = 0.004) compared with the MMP approach. Additionally, patients in the MSV group had also better ROM at 4-6 weeks (P = 0.04), 3 months (P = 0.007), 6 months (P = 0.02) after surgery compared with the patients in the MMP group.

The available evidence indicates that using the MSV approach could be a reasonable alternative to the MMP approach that may potentially ensure the integrity of the quadriceps muscles and enhance the early rapid recovery in primary TKA.

Level II, therapeutic study.