Imageless optical navigation system is clinically valid for total knee arthroplasty.

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Surgical Navigation Technologies

Background:

• Optimal implant positioning is crucial for long-term total knee arthroplasty (TKA) survival.
• Computer-assisted navigation (CAN) enhances accuracy in femoral and tibial bone cuts.
• Imageless CAN offers advantages like reduced cost, radiation, and procedure time compared to image-based systems.

Purpose of the Study:

• To evaluate the clinical accuracy of an imageless optical navigation system for TKA.
• To compare intra-operative measurements from the navigation system with post-operative radiographic assessments.

Main Methods:

• Retrospective review of 42 primary TKA patients using CAN.
• Assessment of femoral and tibial component coronal alignment via post-operative radiographs.
• Comparison of radiographic alignment with intra-operative CAN measurements using Bland-Altman analysis.

Main Results:

• Mean absolute differences between navigation and radiographic measurements were 1.16° (femoral) and 1.76° (tibial).
• 88% of coronal measurements were within ±3°, and 99% were within ±5°.
• Bland-Altman analysis showed a slight bias, with CAN measurements averaging 0.52° less than radiographic measurements.

Conclusions:

• The optical imageless navigation system demonstrates clinical accuracy in measuring femoral and tibial coronal cuts.
• Measurements were within 2.0° of post-operative radiographic assessments, supporting its use in TKA.
• This technology provides a reliable method for achieving precise bone cuts in total knee arthroplasty.