Two-Dimensional Versus Three-Dimensional Preoperative Planning in Total Hip Arthroplasty

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Preoperative planning in total hip arthroplasty (THA) is crucial for accurate implant sizing and positioning.
• Traditional methods utilize radiographs or CT scans for 2D templating.
• Advanced 3D planning offers potential for improved surgical outcomes.

Purpose of the Study:

• To compare the accuracy of 3D versus 2D preoperative planning in primary THA.
• To evaluate the restoration of the center of rotation (COR), combined offset, and leg length.
• To assess the impact of osteoarthritis (OA) patterns on planning method effectiveness.

Main Methods:

• Sixty patients undergoing primary THA for hip osteoarthritis were included.
• Patients were randomly allocated to robotic arm-assisted or conventional THA.
• Both 2D digital templating and 3D planning using robotic software were performed, with measurements on CT scanograms using the contralateral hip as reference.

Main Results:

• 3D templating demonstrated significantly less medialization of the horizontal COR and more accurate vertical COR restoration compared to 2D.
• 3D planning achieved superior planned restoration of leg length.
• 3D planning showed better reproducibility for implant sizes and angles, with distinct benefits noted for different OA patterns.

Conclusions:

• 3D preoperative planning enhances the accuracy of restoring native hip joint mechanics in THA.
• Significant differences exist between 2D and 3D planning, particularly influenced by OA subtypes.
• These findings provide valuable insights for clinicians utilizing 2D planning in THA.