Anatomic Factors Associated With Osteochondral Allograft Matching for Trochlear Cartilage Defects: A...

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Computational Anatomy

Background:

• Articular step-off in osteochondral allografts impacts joint contact pressures.
• Current donor selection relies on basic anatomic parameters (trochlear length, width, tibial width).

Purpose of the Study:

• To identify anatomic factors predicting optimal graft matching using 3D simulation.
• To improve donor-recipient matching for osteochondral allografts.

Main Methods:

• Generated 3D trochlear models from 10 cadaveric specimens.
• Simulated virtual graft transplantation into various defect sizes and locations.
• Calculated cartilage/bone incongruity and articular step-off.
• Used regression models to identify predictors of graft mismatch.

Main Results:

• Ideal matches were achieved for all superolateral defects but only 15-53% of central defects.
• Laterality, sulcus angle, sagittal angle, lateral radius of curvature, and medial facet width predicted ideal graft matching.
• Increased sagittal and sulcus angle mismatch significantly increased step-off in proud central grafts.

Conclusions:

• Sagittal angle, sulcus angle, and lateral radius of curvature mismatch are crucial for optimal donor allograft selection, particularly for large central defects.
• Mismatch parameters can be defined to guide donor selection and minimize articular step-off.