Table 1.

The reduction in human cancellous bone stiffness and strength associated with a 6% difference in bone volume or mass is shown. The 95% confidence interval is reported if available, otherwise the range across all cited studies is shown. A factor that causes a greater change in bone stiffness or strength than that caused by a 6% reduction in bone volume (the first row) has the potential to explain how bone turnover can influence fracture risk independent of bone quantity.

Process through which bone remodeling modifies bone mass	Difference in Bone Mass (%)	Expected Reduction in Stiffness (%)	Expected Reduction in Strength (%)	Source
Reduction in bone volume	−6% (Volume)	12–16%	9–14%	Empirical power law models [14, 17–21]
Reduction in average tissue degree of mineralization from 65% to 62% ash by weight.	−6%(Bone Mineral Content)	11–13%	11–13%	95% confidence interval from empirical power law models [41]
Intraspecimen variation in tissue degree of mineralization	0% Reduction in bone mass; Increase in COV of tissue mineralization from 20% to 50%	14–24%	Not Yet Evaluated	Micro-computed tomography based finite element models [45, 46]
Removal of Trabeculae	−6% (Volume)	3–39%	18–35%	3D cellular solid finite element models [50, 51]
Addition of Remodeling Cavities	−6% (Volume)	12–47%	13–61%	Micro-computed tomography based finite element models [53, 55]