The literature is inconclusive on the development of adjacent-level vertebral fracture after initial cement augmentation. A preliminary hypotheses is that cement injection exaggerates force transmission to the adjacent vertebral bodies, thereby predisposing those levels to future fractures. A sandwich vertebra is an intact vertebral body located between 2 previously cemented vertebrae. The purp...

The segmental body plan of vertebrates arises from the metameric organization of the paraxial mesoderm into somites. Each mesodermal somite is subdivided into at least two distinct domains: rostral and caudal. The segmental pattern of dorsal root ganglia, sympathetic ganglia and nerves is imposed by differential properties of either somitic domain. In the present work, we have extended these st...

Duplication of the vertebral artery is a rare developmental anomaly. Duplication and fenestration are terms often used incorrectly and interchangeably in the literature. To the best of our knowledge, this is the first report to describe bilateral duplication of the extracranial vertebral artery. Bilaterally, there are 2 separate origins of each vertebral artery from the corresponding subclavian...

Different spine models have placed the IAR at various locations in the spine; more commonly, the central region of the intervertebral disk, the middle region of the subjacent vertebra, and the central region of the vertebral body. A computer simulation model of the cervical spine (C2-T1) was developed to investigate sagittal plane kinematics for different placements of the vertebral axis of rot...

One male patient at 59 years old of age was diagnosed as cervical myelopathy for unsteady gait and stiff lower limbs, followed by cervical 3/4 and 5/6 discectomy plus bone grafting and internal fixation, when processing the superior endplate of left cervical 4 disk, a large number of arterial bleeding occurred, which was stopped by packing method, and followed by continued cervical discectomy p...

Substantial data exist from cadaveric and magnetic resonance imaging studies regarding the position of the conus medullaris in normally developed adults. However, no large studies have documented the position of the conus medullaris in patients with diagnosed lumbar spinal stenosis. To goal of the current study was to determine the position of the conus medullaris within a living adult populati...

BACKGROUND AND PURPOSE There are few comparative studies regarding morphologic changes after kyphoplasty and vertebroplasty. The purpose of this study was to compare restoration of vertebral body height and wedge angle and cement leakage with kyphoplasty and vertebroplasty in osteoporotic compression fractures. MATERIALS AND METHODS Forty patients (57 vertebrae) were treated with kyphoplasty,...

The preoperative MR findings in 11 patients, all of whom had developed recurrent low back pain after surgery for herniated lumbar intervertebral disk, were correlated with the surgical findings to determine possible criteria for distinguishing recurrent disk herniation from postoperative scar (extradural fibrosis). The preoperative MR findings agreed with the surgical findings in seven of eight...

BACKGROUND Prior studies that have concluded that disk degeneration uniformly precedes facet degeneration have been based on convenience samples of individuals with low back pain. We conducted a study to examine whether the view that spinal degeneration begins with the anterior spinal structures is supported by epidemiologic observations of degeneration in a community-based population. METHOD...

Objective: To determine the biomechanical effect of an intervertebral spacer on construct stiffness in a PVC model and cadaveric canine cervical vertebral columns stabilized with monocortical screws/polymethylmethacrylate (PMMA). Study Design: Biomechanical study. Sample population: PVC pipe; cadaveric canine vertebral columns Methods: PVC model – PVC pipe was used to create a gap model mimicki...