Effect of Rotational Component Alignment on Clinical Outcome 5 to 7 Years After TKA With the Columbus Knee System

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Total knee arthroplasty (TKA) aims to restore function and alleviate pain in patients with knee osteoarthritis.
• Component alignment is a critical factor influencing TKA success, but the specific impact of rotational alignment remains debated.

Purpose of the Study:

• To investigate the association between rotational alignment of femoral and tibial components and patient-reported outcomes after TKA.
• To determine if femorotibial rotational mismatch affects functional outcomes following TKA.

Main Methods:

• A cohort of 96 patients undergoing TKA with a minimum 5-year follow-up was analyzed.
• Computed tomography (CT) scans of 55 patients were used to assess femoral and tibial component rotational alignment.
• Patient outcomes were evaluated using the Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and SF-36 Health Survey.

Main Results:

• Femoral component malrotation was identified in 15.5% of patients.
• Tibial component malrotation and femorotibial rotational mismatch were observed in 38.2% and 29.1% of patients, respectively.
• Significant femoral component malrotation (>3°) correlated with poorer OKS and KOOS scores, whereas tibial malrotation and femorotibial mismatch did not significantly impact outcomes.

Conclusions:

• Internal or external femoral malalignment exceeding 3° is detrimental to subjective and objective outcomes 5-7 years post-TKA.
• Tibial component malrotation and femorotibial rotational mismatch, though common, do not appear to compromise functional outcomes in the long term.
• Precise rotational alignment of the femoral component is crucial for optimizing patient satisfaction and function after total knee replacement.