The role of bone metastases on the mechanical competence of human vertebrae

Marco Palanca; Giulia Cavazzoni; Enrico Dall'Ara

doi:10.1016/j.bone.2023.116814

The role of bone metastases on the mechanical competence of human vertebrae

Bone. 2023 Aug:173:116814. doi: 10.1016/j.bone.2023.116814. Epub 2023 May 29.

Authors

Marco Palanca¹, Giulia Cavazzoni², Enrico Dall'Ara³

Affiliations

¹ Dept of Oncology and Metabolism, The University of Sheffield, Sheffield, UK; INSIGNEO Institute for In Silico Medicine, The University of Sheffield, Sheffield, UK; Dept of Industrial Engineering, Alma Mater Studiorum - University of Bologna, Bologna, Italy. Electronic address: m.palanca@sheffield.ac.uk.
² Dept of Oncology and Metabolism, The University of Sheffield, Sheffield, UK; INSIGNEO Institute for In Silico Medicine, The University of Sheffield, Sheffield, UK; Dept of Industrial Engineering, Alma Mater Studiorum - University of Bologna, Bologna, Italy.
³ Dept of Oncology and Metabolism, The University of Sheffield, Sheffield, UK; INSIGNEO Institute for In Silico Medicine, The University of Sheffield, Sheffield, UK.

PMID: 37257631
DOI: 10.1016/j.bone.2023.116814

Abstract

Spine is the most common site for bone metastases. The evaluation of the mechanical competence and failure location in metastatic vertebrae is a biomechanical and clinical challenge. Little is known about the failure behaviour of vertebrae with metastatic lesions. The aim of this study was to use combined micro-Computed Tomography (microCT) and time-lapsed mechanical testing to reveal the failure location in metastatic vertebrae. Fifteen spine segments, each including a metastatic and a radiologically healthy vertebra, were tested in compression up to failure within a microCT. Volumetric strains were measured using Digital Volume Correlation. The images of undeformed and deformed specimens were overlapped to identify the failure location. Vertebrae with lytic metastases experienced the largest average compressive strains (median ± standard deviation: -8506 ± 4748microstrain), followed by the vertebrae with mixed metastases (-7035 ± 15605microstrain), the radiologically healthy vertebrae (-5743 ± 5697microstrain), and the vertebrae with blastic metastases (-3150 ± 4641microstrain). Strain peaks were localised within and nearby the lytic lesions or around the blastic tissue. Failure between the endplate and the metastasis was identified in vertebrae with lytic metastases, whereas failure localised around the metastasis in vertebrae with blastic lesions. This study showed for the first time the role of metastases on the vertebral internal deformations. While lytic lesions lead to failure of the metastatic vertebra, vertebrae with blastic metastases are more likely to induce failure in the adjacent vertebrae. Nevertheless, every metastatic lesion affects the vertebral deformation differently, making it essential to assess how the lesion affects the bone microstructure. These results suggest that the properties of the lesion (type, size, location within the vertebral body) should be considered when developing clinical tools to predict the risk of fracture in patients with metastatic lesions.

Keywords: Digital volume correlation; Ex vivo test; Failure location; Metastasis; Strain analysis; Vertebrae.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bone Neoplasms* / diagnostic imaging
Bone Neoplasms* / pathology
Fractures, Bone* / pathology
Humans
Lumbar Vertebrae
Spinal Fractures* / pathology
Spine / pathology
X-Ray Microtomography