In vivo measurement of vertebral deformation using digital tomosynthesis based digital volume correlation

Area of Science:

• Biomedical Engineering
• Orthopedics
• Radiology

Background:

• Osteoporotic vertebral fractures are common and lead to complications.
• Current bone mineral density assessments lack accuracy in identifying at-risk individuals.
• A novel technique, DTS-DVC, inspired by lab methods, assesses bone mechanics using medical imaging.

Purpose of the Study:

• To evaluate the in vivo precision errors of DTS-DVC.
• To determine the utility of DTS-DVC in identifying mechanically compromised vertebrae.
• To assess differences in vertebral mechanics between fractured and non-fractured individuals.

Main Methods:

• Digital tomosynthesis (DTS) images were acquired from patients in supine and standing positions, with and without added weight.
• Digital Volume Correlation (DVC) was applied to DTS images to calculate endplate-to-endplate displacement, stiffness, and compliance.
• Seven patients with vertebral fractures (Fx) and twelve without (NFx) participated.

Main Results:

• Total measurement error for DTS-DVC was low (0.017-0.019 mm).
• All measured biomechanical parameters significantly changed with loading (p < 0.0001 to p < 0.05).
• Fractured vertebrae exhibited significantly higher endplate-to-endplate displacement and heterogeneity compared to adjacent intact vertebrae.

Conclusions:

• DTS-DVC is feasible for in vivo biomechanical assessment of vertebrae.
• This technique has the potential to improve the understanding and clinical assessment of vertebral fracture risk.
• Further investigation is warranted to refine and validate DTS-DVC for clinical application.