Patient-specific instrumentation improved axial alignment of the femoral component, operative time and perioperative blood loss after total knee arthroplasty

23 randomized controlled trials were included in this meta-analysis which compared component alignment, operative time, length of stay and blood loss between cases of total knee arthroplasty completed with patient-specific instrumentation and cases completed with conventional instrumentation. Absolute deviation and incidence of outliers did not significantly differ between groups for overall coronal lower limb alignment, coronal and sagittal femoral component alignment, and coronal and sagittal tibial component alignment. While absolute deviation in axial femoral component alignment was lower among PSI groups, the difference between groups in outliers in axial femoral component alignment was not significant. Operative time was statistically significantly shorter among PSI groups by approximately 7.5 minutes, and blood loss was statistically significantly lower among PSI groups by approximately 83mL. Length of stay did not significantly differ between groups.