Calculating the probability that microcracks initiate resorption spaces

Area of Science:

• Bone Biology
• Skeletal Remodeling
• Mechanobiology

Background:

• Previous research by Burr et al. (1985) suggested microcracks initiate bone remodeling events.
• The probability calculations supporting this conclusion warrant further examination of underlying assumptions and limitations.
• Minor errors in the original probability calculations have been identified and corrected.

Purpose of the Study:

• To critically analyze the assumptions and limitations of the probability calculation linking microcracks to bone remodeling.
• To re-evaluate and correct errors in the original probability calculations.
• To investigate the factors influencing the observed association between microcracks and resorption spaces in bone.

Main Methods:

• Re-examination of the probability calculation methodology used by Burr et al. (1985).
• Correction of identified minor calculation errors.
• Development of a factor (F) to account for shared cement lines between osteons containing cracks and resorption spaces.

Main Results:

• The probability of association between cracks and resorption spaces is highly dependent on factor F.
• Factor F is influenced by measurement criteria, osteon population density, and the crack initiation mechanism.
• Theoretical maximum (nmax) of osteons with both cracks and resorption spaces increases with r, c, and F, but decreases with density (d).

Conclusions:

• The direct experimental demonstration of a link between cracks and resorption spaces is challenged by a larger nmax.
• Accurate assessment of microcrack-induced remodeling requires careful consideration of spatial relationships and measurement parameters.
• The findings necessitate a nuanced understanding of how microcracks may initiate bone remodeling events.