Comparing the mid-vastus and medial parapatellar approaches in total knee arthroplasty: A meta-analysis of short term outcomes

Proponents of a mid-vastus (MV) approach for primary total knee arthroplasties (TKA) stress its importance in preserving function of the extensor mechanism with earlier rehabilitation and decreased prevalence of lateral release. We conducted a meta-analysis of randomised and quasi-randomised controlled trials to compare functional outcomes of the standard medial parapatellar (PP) and mid-vastus (MV) approaches in primary knee arthroplasties.

The study was conducted according to the guidelines described in the Cochrane Handbook for Systematic Reviews of Interventions. Methodological features were rated independently by two reviewers.

We included 18 studies involving 1040 patients with mean age of 69 (SD ± 2.7) for the MV and 68.8 (SD ± 2.8) for the PP group. Using a MV approach led to significant improvement in flexion (mean difference (MD) 8.88, 95% confidence interval (CI) 4.50 to 13.25, P < 0.01) and visual analogue scale score (MD − 1.72 95% CI − 2.08 to − 1.36, P < 0.01) in the first week postoperatively and reduced the number of required lateral releases (risk difference − 0.16 95% CI − 0.30 to − 0.01, P = 0.03) with no increase in complication rates.

We conclude that the MV approach may provide an alternative to the standard PP approach with earlier rehabilitation and decreased lateral release rates in primary TKA and no increase in complication rates.