Component Alignment in Simultaneous Bilateral versus Unilateral Total Knee Arthroplasty.

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Total knee arthroplasty (TKA) is a common procedure for knee osteoarthritis.
• Simultaneous bilateral total knee arthroplasty (SBTKA) offers potential benefits like reduced overall recovery time.
• Understanding component alignment in SBTKA versus unilateral TKA (UTKA) is crucial for optimal surgical outcomes.

Purpose of the Study:

• To investigate and compare component alignment in the coronal and sagittal planes between the first and second knees in SBTKA and in UTKA.

Main Methods:

• Radiographic analysis of component alignment (femoral and tibial) in coronal (alpha and beta angles) and sagittal (gamma and delta angles) planes.
• Inclusion of 274 SBTKAs and 198 UTKAs, categorized into three groups: right knee SBTKA, left knee SBTKA, and UTKA.
• Preoperative assessment of anatomical varus angle and Kellgren-Lawrence gonarthrosis grade.

Main Results:

• No significant differences were found in preoperative anatomical varus angle or gonarthrosis grade among the groups.
• Coronal plane alignment (femoral alpha angle, tibial beta angle) showed no statistically significant differences between SBTKA and UTKA groups.
• Sagittal plane alignment (femoral gamma angle, tibial delta angle) also demonstrated no significant differences across all study groups.

Conclusions:

• Component angular alignment in total knee arthroplasty is comparable whether performed simultaneously on both knees or unilaterally.
• These findings suggest that SBTKA can achieve similar component positioning to UTKA, potentially simplifying surgical planning and execution.