Biomechanics of Vertebral Bone Augmentation

Restoration of Spinal Alignment and Disk Mechanics following Polyetheretherketone Wafer Kyphoplasty with StaXx FX

“…Although new adjacent fractures do occur with or without the use of vertebroplasty or kyphoplasty, there is still no adequate documentation on the risk of adjacent fracture after vertebral augmentation. 18,19 This is probably dependent more upon load transmission to the surrounding structures and maintenance of spine alignment rather than upon changes in the vertebral bone stiffness. 14 In an osteoporotic vertebral body, kyphosis increases peak stresses up to 2.5-fold.…”

“…If kyphotic spinal alignment alters load sharing and disturbs the balance between vertebral segments leading to an increased likelihood of new fractures, any effort to correct the kyphosis to prevent subsequent vertebral fractures is justified. 4,11,18 Gaitanis et al 11 showed that cement augmentation with hyperextension almost totally restored anterior and middle vertebral column height; however, posterior height was not corrected adequately. The results from the current study closely match those of Gaitanis et al 11 in terms of restoration of anterior height, whereas StaXx FX was able to nearly equally reduce both the vertebral and segmental kyphosis.…”

“…14,21,22 The result of decreased nuclear pressure is increased stress on the annulus and apophyseal ring. 18,23 Tzermiadianos et al 14 tested the hypothesis that the inability of the disk to generate adequate IDP after vertebral fractures in human cadaveric specimens will increase loading of adjacent vertebra predisposing them to fracture even in the absence of a kyphotic deformity. In this study, after cement augmentation, disk pressure increased during flexion by 15 Ϯ 11% in the specimens with intact endplates, whereas it was decreased by 19 Ϯ 26.7% in the disks with the fractured endplates.…”

The Quality of Applied Bone Cement Depends on the Chemical Composition of the Application System

“…The bone cement was applied by hand, therefore application systems were not necessary. In the time course of the use of bone cement, new and better injectable cements were developed for spinal application [9,10]. Several studies in the past showed an increased exposure to fumes during the mixing procedure of PMMA [11].…”

Vertebral compression fractures: a review of current management and multimodal therapy

“…Finally, fractures may develop in vertebrae adjacent to the augmented vertebral body. Some researchers, for example, Hadley et al, have speculated that this is due to increased loading on the adjacent levels secondary to stiffness of the augmented body,58 but similar incidences of adjacent fracture with untreated patients have been reported, suggesting that this is a consequence of the patient’s existing osteoporotic disease as opposed to a result of the intervention 53…”