Distance mapping for quantifying contact surface area and inter-bone distance in wrist CT imaging: a comparative...

Area of Science:

• Orthopedics and Radiology
• Biomechanical Engineering
• Medical Imaging Analysis

Background:

• Osteoarthritis assessment relies on articular surface congruency and cartilage integrity.
• Computed Tomography (CT) scanning and bone-to-bone distance mapping offer non-invasive evaluation methods.
• Distance maps visualize joint inter-bone distances, representing contact surface area.

Purpose of the Study:

• To evaluate the sensitivity of different distance map generation methods to threshold settings.
• To compare these methods in radioscaphoid, radiolunate, and scapholunate joints.
• To determine the most robust method for assessing joint contact in osteoarthritis.

Main Methods:

• Analysis of static 3D-CT scans from healthy and pathological wrists.
• Generation of distance maps using various methods with different distance and angle thresholds.
• Application of a mixed-effects model to compare method sensitivity to threshold variations.

Main Results:

• Different methods and thresholds significantly impact contact area and distance measures.
• The method combining perpendicular distance and angle thresholds demonstrated the least sensitivity to threshold changes.
• This preferred method yielded minimal variations in contact surface area and bone-to-bone distances.

Conclusions:

• The choice of method and thresholds in distance mapping affects osteoarthritis assessment outcomes.
• Combining perpendicular distance and angle thresholds provides a more stable and reliable measure of joint contact.
• This approach enhances the non-invasive evaluation of joint integrity using CT imaging.