Three-Dimensional Preoperative Planning Software for Hip Resurfacing Arthroplasty.

Area of Science:

• Orthopedic Surgery
• Medical Imaging
• Surgical Planning Software

Background:

• Three-dimensional (3D) planning improves visualization and implant sizing in hip arthroplasty, potentially reducing surgical time and complications.
• Hip resurfacing arthroplasty (HRA) is technically demanding, with challenges in accurate implant placement.

Purpose of the Study:

• To evaluate the validity, reliability, and usability of a preoperative 3D Hip Planner software specifically for HRA.
• To assess the software's accuracy in determining implant size, stem-shaft angle, and cup inclination angle compared to 2D planning.

Main Methods:

• Fifty random HRA cases were planned twice by junior trainees using the 3D Hip Planner within a month.
• Outcome measures (implant size, stem-shaft angle, cup inclination) were compared between 3D and 2D planning.
• Software usability was assessed using an adapted Unified Theory of Acceptance and Use of Technology (UTAUT) survey.

Main Results:

• Bland-Altman analysis showed minimal mean differences between 3D and 2D planning for stem-shaft (0.7°) and inclination (-0.6°) angles.
• Inter-rater reliability showed biases of -2° for stem-shaft and 3° for inclination angles.
• High test-retest reliability (r=0.98) and significant association (r=0.91) were found for femoral implant size, with repeatability within ±2° and ±3° for angles.

Conclusions:

• The 3D Hip Planner demonstrates validity and reliability for preoperative planning in hip resurfacing arthroplasty.
• The software shows significant potential for optimizing the quality and accuracy of surgical planning in HRA.
• Usability surveys indicated positive user acceptance, with 70-90% agreeing on improved expectancy in key domains.