Local analysis of trabecular bone fracture

Area of Science:

• Biomechanics
• Materials Science
• Orthopedics

Background:

• Assessing bone fracture risk is crucial for preventing traumatic injuries.
• Bone mineral density and bone volume fraction have limitations in identifying failure zones.
• A need exists for additional parameters to fully describe bone failure events.

Purpose of the Study:

• To compare fracture and non-fracture zones in trabecular bone.
• To identify morphometrical parameters that best describe the trabecular fracture zone.
• To analyze local structural differences influencing bone failure.

Main Methods:

• Micro-computed tomography (micro-CT) scanning of trabecular bone specimens before and after mechanical testing.
• Automatic registration to identify the 3D fracture zone by comparing pre- and post-failure datasets.
• Morphometrical analysis of parameters including bone volume fraction, off-axis angle, structural model index, and connectivity density.

Main Results:

• Ten out of twelve morphometrical parameters showed statistically significant differences between fracture and non-fracture zones.
• Off-axis angle, structural model index, and connectivity density exhibited differences greater than 30% with reduced distribution overlap.
• Bone volume fraction showed significant but smaller differences with considerable distribution overlap.

Conclusions:

• Trabecular bone exhibits significant structural differences between fractured and non-fractured areas.
• Off-axis angle, structural model index, and connectivity density are superior indicators of trabecular bone fracture zones compared to bone volume fraction.
• These findings refine the understanding of bone failure mechanisms and improve fracture risk assessment.