Sagittal femoral morphology is not associated with robotic planning or soft‐tissue balance during robotic‐assisted total knee arthroplasty: An analysis from the Brescia Knee Research Group

PURPOSE: To evaluate the influence of sagittal femoral morphology on robotic planning parameters and intraoperative soft-tissue balance in robotic-assisted total knee arthroplasty (TKA). It was hypothesised that sagittal femoral morphology has limited impact on intraoperative planning and laxity. METHODS: This retrospective study analysed a prospectively maintained database of patients undergoing primary robotic-assisted TKA between January 2021 and November 2022. Preoperative radiographic parameters included mechanical hip-knee-ankle angle (mHKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA) and posterior tibial slope (PTS). Sagittal femoral morphology was assessed using anterior femoral offset (AFO), posterior femoral offset (PFO) and anteroposterior femoral size (AP size). Intraoperative robotic data included femoral resections, femoral flexion, rotation referenced to the posterior condylar axis (PCA) and transepicondylar axis (TEA) and medial-lateral laxity in extension and flexion. Associations between sagittal morphology, planning parameters and soft-tissue balance were analysed using linear and logistic regression models. RESULTS: ≈ 0). Similarly, sagittal morphology was not associated with medial-lateral laxity imbalance in extension or flexion, either at the initial or final assessment (all p > 0.05). CONCLUSIONS: Sagittal femoral morphology does not significantly influence robotic planning or intraoperative soft-tissue balance in robotic-assisted TKA. These findings suggest that sagittal anatomy alone is not a primary determinant of surgical planning or gap behaviour, supporting the need for a comprehensive, patient-specific and multiplanar approach. LEVEL OF EVIDENCE: Level III.