Abstract
Surgeon handedness may influence prosthetic alignment in conventional manual total knee arthroplasty (CM-TKA), but whether robotic assistance mitigates this effect remains unclear. This study investigated whether Mako robot-assisted TKA (MA-TKA) mitigates handedness-related discrepancies in alignment accuracy and perioperative outcomes. This retrospective cohort study included 1160 patients who underwent unilateral TKA performed by three experienced right-handed surgeons. Patients were divided into four groups based on surgical technique and operated side: MA-left (n = 84), MA-right (n = 92), CM-left (n = 453), and CM-right (n = 531). Operative duration, tourniquet time, hospital stay, blood loss, and radiographic parameters (mechanical tibiofemoral angle, mechanical lateral distal femoral angle, medial proximal tibial angle, lateral femoral component and lateral tibial component) were compared. Outliers were defined as ≥ 3° deviation from target values. Baseline characteristics were comparable across groups. MA-left surgery had the longest operative and tourniquet times, while MA-right surgery yielded the lowest blood loss. Both MA groups had significantly shorter hospital stays and lower blood loss than CM groups (P < 0.001). Radiographic accuracy was superior in MA groups, with no differences between MA-left and MA-right for any parameter. In CM groups, left-sided procedures showed significantly poorer alignment and higher outlier rates than right-sided procedures (P < 0.05). MA-TKA mitigates the negative impact of surgeon handedness on prosthetic alignment, achieving homogeneous accuracy regardless of operated side. Despite slightly longer operative times, MA-TKA reduces blood loss and shortens hospital stay, offering tangible clinical value.