Sex- and site-specific reference data for size-invariant properties using multi-stack HRpQCT.

Area of Science:

• Orthopedics and Bone Biology
• Medical Imaging and Diagnostics
• Biomechanical Engineering

Background:

• High-resolution peripheral quantitative computed tomography (HRpQCT) is an advanced imaging technique for assessing bone microarchitecture and predicting strength, surpassing traditional methods like DXA.
• Current HRpQCT reference data, often based on single thin slices, may not fully represent clinically relevant bone regions and can be limited by size-dependent parameters, potentially masking true bone quality changes.
• There is a need for size-independent parameters derived from multi-stack HRpQCT to improve the accuracy and sensitivity of longitudinal bone health assessments.

Purpose of the Study:

• To establish the first age-, sex-, and site-specific reference data for novel multi-stack HRpQCT parameters at the distal radius and tibia.
• To identify size-independent parameters that are most sensitive to age-related changes for improved bone health assessment.
• To evaluate the utility of these parameters for refined longitudinal monitoring and fracture risk evaluation.

Main Methods:

• Recruited 381 healthy participants (144 female, 237 male) from a predominantly Caucasian population, aged 20-92 years.
• Acquired multi-stack HRpQCT scans at the distal radius and tibia using second-generation scanners.
• Selected six size-independent parameters: total volumetric BMD, cortical volumetric BMD, relative cortical thickness, trabecular degree of anisotropy, trabecular bone volume over total volume, and apparent yield stress, for analysis.

Main Results:

• Generated comprehensive age-, sex-, and site-specific reference data for multi-stack HRpQCT parameters.
• Identified cortical volumetric BMD, particularly in the weight-bearing tibia in women, as the most sensitive size-independent parameter to age-related changes.
• Demonstrated good agreement between single-stack and multi-stack derived densitometric and microstructural properties, supporting cross-protocol comparisons.

Conclusions:

• Multi-stack HRpQCT provides a refined set of size-independent variables for comprehensive bone health assessment.
• These novel parameters offer improved sensitivity for detecting age-related bone changes and enhance longitudinal monitoring capabilities.
• The findings support the use of multi-stack HRpQCT for more accurate fracture risk prediction and personalized bone management strategies.