Component sizing in total knee arthroplasty: patient-specific guides vs. computer-assisted navigation

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Medical Technology

Background:

• Total knee arthroplasty (TKA) aims for accuracy and reproducibility.
• Patient-specific guides (PSG) and computer-assisted navigation (CAN) are advanced technologies used in TKA.
• Comparing the predictive accuracy of PSG and CAN for femoral component size is crucial for surgical planning.

Purpose of the Study:

• To compare the anatomical registration and femoral component size prediction accuracy between PSG and CAN systems in TKA.
• To evaluate the methodologies employed by PSG and CAN for determining optimal femoral component size.
• To assess the clinical relevance of PSG and CAN predictions against actual surgical component selection.

Main Methods:

• A comparative study involving 111 patient-specific guides (PSG) total knee arthroplasties (TKA).
• Thirty of these TKA cases were concurrently evaluated using computer-assisted navigation (CAN).
• Femoral component size predictions from both PSG and CAN were compared to the actual component selected by the surgeon.

Main Results:

• The PSG system demonstrated superior accuracy and precision in predicting femoral component size for TKA compared to the CAN system.
• PSG predictions more closely aligned with the surgeon's final component selection than CAN predictions.
• The study found PSG to be more reliable for determining optimal femoral component size in TKA.

Conclusions:

• Surgeon's final component selection in TKA was more frequently aligned with PSG predictions than CAN predictions.
• Intraoperative surface registration via CAN may be less accurate than preoperative 3D MRI reconstructions for femoral component sizing.
• PSG, utilizing preoperative imaging, appears to offer more reliable femoral component sizing in TKA than intraoperative navigation systems.