Secondary osteon variants and remodeling in human bone

Area of Science:

• Paleopathology
• Human Osteology
• Bone Histology

Background:

• Human cortical bone exhibits secondary osteon variants, including drifting osteons and Type II osteons.
• The biological significance and associations of these osteon variants with bone remodeling remain poorly understood.
• Previous research suggested potential links to age, biomechanics, diet, and mineral homeostasis.

Purpose of the Study:

• To investigate the relationship between secondary osteon variants (Type II and drifting osteons) and static measures of bone remodeling.
• To determine if osteon parameters and densities differ based on the presence or absence of these variants.
• To explore potential biological and social influences on osteon variant occurrence.

Main Methods:

• Histomorphometric analysis of 112 thin sections from a late English Medieval adult human femoral osteological collection.
• Categorization of osteon variants (Type II and drifting) and assessment of remodeling indicators derived from osteon parameters (area, diameter, area ratios) and densities.
• Statistical comparison of remodeling indicators between groups with and without specific osteon variants, considering age, sex, and socio-economic status.

Main Results:

• Sporadic statistically significant differences were observed.
• The Haversian canal to osteon area ratio differed with Type II osteon presence (p=0.017).
• Type II osteons were more common in males (p=0.048), and drifting osteons were associated with smaller osteon (p=0.049) and Haversian canal areas (p=0.05).

Conclusions:

• The study identified limited consistent relationships between osteon variants and bone remodeling indicators.
• Observed associations, such as sex differences in Type II osteon prevalence, may relate to biological or social factors like physiological recovery.
• The general lack of strong correlations suggests that osteon variants likely arise from natural variation within the population.