Artificial Intelligence Autonomously Measures Cup Orientation, Corrects for Pelvis Orientation, and Identifies...

Area of Science:

• Orthopedic surgery
• Medical imaging
• Artificial intelligence in medicine

Background:

• Cup orientation in total hip arthroplasty (THA) is critical for preventing impingement and dislocation.
• Manual measurement of cup orientation from radiographs is time-consuming and inaccurate.
• Accurate assessment of cup orientation is essential for successful THA outcomes.

Purpose of the Study:

• To develop and validate an artificial intelligence (AI) program for autonomous measurement of cup orientation from antero-posterior pelvic radiographs.
• To assess the AI program's ability to correct for pelvic orientation and identify cup retroversion.
• To compare the accuracy and efficiency of AI-based measurements against traditional manual methods.

Main Methods:

• Utilized 504 computed tomographic (CT) scans from 2,945 patients undergoing THA for 3D reconstruction and cup orientation measurement.
• Developed an AI model trained on 4,000 X-rays, with data augmentation creating 4,000,000 training images.
• Validated the AI model's accuracy against CT measurements using a test group of 690 radiographs.

Main Results:

• AI predictions for cup orientation were obtained rapidly, averaging 0.22 ± 0.03 seconds per radiograph.
• AI measurements demonstrated high correlation with CT scans (Pearson's r = 0.976 for anteversion, 0.984 for inclination), significantly outperforming manual measurements (r = 0.650 and 0.687).
• The AI model achieved 100.0% accuracy in identifying retroverted cups (17 cases) from single antero-posterior radiographs.

Conclusions:

• AI algorithms can accurately measure cup orientation from radiographs, correcting for pelvic tilt and surpassing manual measurement accuracy.
• This AI approach offers a timely and efficient solution for assessing cup orientation in THA.
• This represents the first AI-driven method capable of identifying retroverted cups using a single antero-posterior radiograph.