Fracture Characterization of Human Cortical Bone Under Mode I Loading

Area of Science:

• Biomaterials Science
• Mechanical Engineering
• Orthopedic Research

Background:

• Understanding bone fracture toughness is crucial for orthopedic implant design and fracture healing.
• Existing methods for measuring bone fracture energy can be complex and require large samples.
• Human cortical bone exhibits complex fracture behavior that needs accurate characterization.

Purpose of the Study:

• To develop and validate a miniaturized double cantilever beam (DCB) test for determining human cortical bone fracture energy.
• To implement an advanced data-reduction scheme for improved accuracy.
• To establish a cohesive law that accurately represents bone's mechanical response during fracture.

Main Methods:

• Utilized a miniaturized double cantilever beam (DCB) test setup for pure mode I loading.
• Employed an equivalent crack length data-reduction scheme for enhanced analysis.
• Applied digital image correlation (DIC) to precisely measure crack opening displacement.
• Developed a cohesive zone model (CZM) using the finite-element method (FEM) for validation.

Main Results:

• The miniaturized DCB test successfully determined fracture energy in human cortical bone.
• The equivalent crack length method offered significant advantages over traditional approaches.
• DIC measurements correlated well with the evolving fracture energy.
• The developed cohesive law accurately mimicked the observed mechanical behavior of bone.

Conclusions:

• The miniaturized DCB test provides a reliable and efficient method for assessing bone fracture energy.
• The combination of DIC and CZM offers a robust approach for bone fracture characterization.
• This methodology can aid in the development of improved bone- Grafts and orthopedic treatments.