Advanced imaging assessment of bone quality.

Area of Science:

• Biomedical Engineering
• Radiology
• Orthopedics

Background:

• Bone mineral density (BMD) alone partially predicts bone strength and fracture risk.
• Noninvasive and nondestructive techniques offer complementary structural information.
• Quantitative assessment of bone macrostructure and microstructure is crucial for improved bone strength estimation.

Purpose of the Study:

• To review noninvasive and/or nondestructive techniques for quantitative bone assessment.
• To highlight the limitations and challenges of current bone imaging methods.
• To discuss the clinical applicability and future directions for bone imaging.

Main Methods:

• Dual X-ray absorptiometry (DXA) and computed tomography (CT) for macrostructure.
• Volumetric quantitative CT (vQCT), high-resolution CT (hrCT), and high-resolution MR (hrMR) for in vivo assessment.
• Micro-CT and micro-MR for in vitro analysis of trabecular bone microstructure.

Main Results:

• vQCT, hrCT, and hrMR are suitable for in vivo studies; micro-CT and micro-MR for in vitro.
• Challenges include balancing resolution, sampling size, signal-to-noise, radiation dose, and acquisition time.
• Clinical application requires balancing complex architectural features with simpler densitometry and research needs versus clinical demands.

Conclusions:

• Advanced imaging techniques provide valuable structural bone information beyond BMD.
• Further research is needed to address technical challenges and clinical integration.
• Optimizing techniques for diagnostic accuracy and monitoring reproducibility is essential.