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Comparative Study for Alignment of Extramedullary Guides versus Portable, Accelerometer-Based Navigation in Total
Kazu Matsumoto1, Hiroyasu Ogawa1, Masashi Fukuta2
1Department of Orthopaedic Surgery, Gifu University Graduate School of Medicine, Gifu, Japan.
The Journal of Knee Surgery
|May 2, 2017
Summary
Portable navigation (PN) systems offer comparable accuracy to traditional extramedullary (EM) systems for total knee arthroplasty (TKA) component positioning. Both methods provide satisfactory alignment, though femoral component accuracy requires further improvement in PN systems.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Surgical Navigation
Background:
- Total knee arthroplasty (TKA) component positioning is critical for optimal patient outcomes.
- Extramedullary (EM) systems have been the standard for TKA alignment, often requiring image intensification.
- Portable navigation (PN) devices, utilizing accelerometers, are emerging as an alternative to EM systems.
Purpose of the Study:
- To compare the accuracy of component positioning in TKA between EM and PN systems.
- To evaluate coronal and sagittal plane alignments relative to the mechanical axis of the limb.
Main Methods:
- Retrospective analysis of 100 primary TKAs performed between October 2010 and June 2015.
- Components positioned using either EM or PN systems by multiple surgeons.
- Radiographic evaluation of coronal and sagittal plane alignments of femoral and tibial components.
Main Results:
- Mean postoperative coronal alignment angles for femoral and tibial components were comparable between PN and EM groups.
- Mean postoperative sagittal alignment angles for femoral and tibial components were also comparable between the groups.
- Incidence of component malalignment exceeding 3 degrees was similar for both PN and EM systems.
Conclusions:
- Both PN and EM systems achieve satisfactory coronal and sagittal component alignments in TKA.
- Femoral component alignment was less accurate than tibial component alignment, particularly with the PN system.
- Further technical advancements in PN systems could enhance their accuracy for TKA component implantation.
