PURPOSE: To clarify the influence of biomechanics on post-operative clinical outcomes in bicruciate-retaining total knee arthroplasty (BCR-TKA). METHODS: Severe medial osteoarthritis who underwent BCR-TKA were examined. Each patient was asked to perform a squat (weight-bearing [WB]) and active assisted knee flexion (non-WB [NWB]) under single fluoroscopy surveillance. A 2D-to-3D registration technique was used. Patients were divided into two groups based on their 1-year post-operative patient-reported outcome measures (PROMs) using hierarchical cluster analysis. The rotational alignment on computed tomography, anterior stability at 30° of knee flexion, axial rotation of the femur relative to the tibial component and anteroposterior translation of the medial and lateral femorotibial contact points were measured. RESULTS: Components did not significantly differ between the groups, with 1.6 ± 5.0° and 5.4 ± 4.7° of femoral internal rotation in the low PROM ( CONCLUSION: The femoral component in the low-PROM group was externally rotated across all ranges of motion, and the lateral contact points were posteriorly located in BCR-TKA. LEVEL OF EVIDENCE: Level II, prospective cohort study.