Medial Pivot Total Knee Arthroplasty: Replicating Native Knee Kinematics and Early Clinical Outcomes

Despite advances in total knee arthroplasty (TKA), up to 20% of patients remain dissatisfied, often due to non-physiological knee kinematics associated with conventional cruciate-retaining and posterior-stabilized designs. Medial pivot TKA systems aim to replicate native knee biomechanics by providing a stable medial compartment with controlled lateral femoral rollback.

To evaluate early clinical, functional, and radiological outcomes of primary TKA using a medial pivot knee system in patients with advanced knee osteoarthritis.

This prospective single-center study included 73 patients (82 knees) undergoing primary TKA with a medial pivot knee system between August 2023 and December 2024. Patients with severe deformities or prior knee osteotomies were excluded. All surgeries were performed by a single surgeon using a standardized technique. Clinical outcomes were assessed using the Oxford Knee Score (OKS), WOMAC score, Forgotten Joint Score (FJS), and range of motion (ROM) preoperatively and at 6 weeks, 3 months, and 1 year postoperatively. Radiographs were evaluated for component positioning, loosening, and osteolysis. Patient satisfaction and complications were recorded.

At one year, significant improvements were observed in all outcome measures. Mean OKS improved from 11.3 to 45.1, WOMAC from 29.6 to 88.4, and FJS reached 87.4. Mean ROM increased from 118.4° preoperatively to 121.5°. Excellent or good satisfaction was reported by 97.3% of patients. No radiological loosening or osteolysis was observed. Complications were minimal and successfully managed.

Medial pivot TKA demonstrated excellent short-term functional outcomes, high patient satisfaction, and stable radiological results, suggesting that replication of native knee kinematics may enhance early clinical performance.