Enhanced Mid-Resection Workflow Technique for Severe Varus Deformity Correction Using Robotic-Arm Assisted Total Knee...

Area of Science:

• Orthopedic Surgery
• Robotics in Medicine
• Biomechanical Engineering

Background:

• Robotic-arm assisted total knee arthroplasty (RA-TKA) enhances component positioning and alignment accuracy.
• The effectiveness of RA-TKA in correcting severe varus knee deformities remains under-investigated.
• Existing RA-TKA workflows have limitations in achieving pre-balance for severe varus knees.

Purpose of the Study:

• To establish the utility of RA-TKA in achieving pre-balance for severe varus knee deformities.
• To describe a novel technique for robotic-arm assisted total knee arthroplasty in severe varus knees.
• To develop an algorithm for selecting RA-TKA workflows based on varus deformity severity.

Main Methods:

• A novel "enhanced mid-resection workflow" was developed for RA-TKA.
• This technique involves a provisional postero-medial femoral bone cut in flexion to address osteophytes and capsule tightness.
• Flexion gap balancing is achieved through adjustments in axial component positioning.

Main Results:

• The novel technique successfully achieved pre-balance in severe varus deformities.
• The enhanced mid-resection workflow provides access to remove posterior osteophytes and release the posterior capsule.
• The described technique allows for precise bone cuts to balance the knee in extension.

Conclusions:

• The novel "enhanced mid-resection workflow" is effective for RA-TKA in severe varus knee deformities.
• This technique establishes the utility of RA-TKA in balancing complex knee alignments.
• An algorithm is proposed to guide surgeons in selecting the appropriate RA-TKA workflow for pre-balancing knees.