CT-based structural analyses of vertebral fractures with polymeric augmentation: A study of cadaveric three-level spine segments

• Published in: Computers in biology and medicine 2021-06, Vol.133, p.104395-104395, Article 104395
• Main Authors: Rezaei, Asghar, Giambini, Hugo, Miller II, Alan L., Xu, Hao, Xu, Haocheng, Li, Yong, Yaszemski, Michael J., Lu, Lichun
• Format: Article
• Language: English
• Subjects: Augmentation; Biomechanical Phenomena; Biomechanics of spine; Bone surgery; Cadaver; Cadavers; Compression; Computational neuroscience; Computed tomography; Defects; Female; Fracture strength; Fractures; Humans; Male; Mechanical properties; Mechanical testing; Mechanical tests; Metastases; Metastasis; Pain; Polymers; Polymethyl methacrylate; Polymethylmethacrylate; Polypropylene fumarate; Rigidity; Rigidity analysis; Segments; Software; Spinal Fractures - diagnostic imaging; Spine; Tomography, X-Ray Computed; Vertebrae; Vertebral augmentation; Vertebral fracture; Vertebroplasty
• ISSN: 0010-4825; 1879-0534
• DOI: 10.1016/j.compbiomed.2021.104395

Pathologic vertebral fractures due to metastasis can occur under normal physiologic activities, leading to pain and neurologic deficit. Prophylactic vertebroplasty is a technique used to augment vertebral strength and reduce the risk of fracture. Currently, no technique is available to objectively assess vertebral fracture risk in metastatically-involved vertebral bodies. The aim of the current study was to develop an image-based computational technique to estimate fracture force outcomes during bending. To this end, mechanical testing was performed on intact, simulated defect, PMMA-augmented, and PPF-augmented 3-level spine segments from both sexes under a compression/flexion-type loading condition. The augmentation performance of poly(methyl methacrylate) (PMMA) and poly(propylene fumarate) (PPF) were also evaluated and compared. Cylindrical defects were created in 3-level spine segments with attached posterior elements and ligaments. Using CT images of each segment, a rigidity analysis technique was developed and used for predicting fracture forces during bending. On average, PPF strengthened the segments by about 630 N, resulting in fracture forces similar to those observed in the intact and PMMA-augmented groups. Female spines fractured at about 1150 N smaller force than did male spines. Rigidity analysis, along with age, explained 66% variability in experimental outcomes. This number increased to 74% when vertebral size and age were added to the rigidity analysis as explanatory variables. Both PPF and PMMA similarly increased fracture strength to the level of intact specimens. The results suggest that PPF can be a suitable candidate for augmentation purposes and rigidity analysis can be a promising predicting tool for vertebral fracture forces. •Image-based rigidity analysis is a promising technique to predict fracture forces in augmented spine segments.•Poly(propylene fumarate) (PPF) can be a suitable candidate for augmenting metastatic vertebral bodies.•Female spines fractured at about 1150 N smaller force than did male spines.