How to Quantitatively Balance a Total Knee? A Surgical Algorithm to Assure Balance and Control Alignment

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering

Background:

• Total knee arthroplasty (TKA) aims for optimal knee balance and limb alignment.
• Intra-operative sensors and surgical navigation offer patient-specific feedback for TKA.
• This study quantifies the effects of surgical corrections on knee balance and alignment.

Discussion:

• An average of three surgical corrections were needed post-bone cuts for balanced TKAs.
• Specific soft tissue releases (e.g., arcuate release) and bone adjustments (e.g., tibial insert thickness) significantly alter terminal extension.
• Coronal alignment is notably affected by medial collateral ligament (MCL) pie-crusting, tibial varus, arcuate ligament, and popliteus tendon releases.

Key Insights:

• Each surgical correction demonstrated a distinct impact on intra-articular loads during flexion and extension.
• Soft tissue adjustments play a crucial role in influencing limb alignment across both anatomical planes.
• A presented surgical algorithm aids in achieving knee balance while preserving sagittal and coronal alignment.

Outlook:

• Further research can refine surgical algorithms for TKA based on quantitative biomechanical data.
• Understanding the precise impact of each correction can lead to improved patient outcomes and implant longevity.
• Integration of advanced navigation and sensor technology can enhance precision in TKA procedures.