STUDY DESIGN: A biomechanical and imaging study of human cadaveric spinal motion segments.

OBJECTIVE: To investigate the effect of both disc degeneration and facet joint osteoarthritis on lumbar segmental motion.

SUMMARY OF BACKGROUND DATA: Spinal degeneration includes the osteoarthritic changes of the facet joint as well as disc degeneration. Disc degeneration has been reported to be associated with spinal motion. The association of facet joint osteoarthritis with lumbar segmental ...

STUDY DESIGN: An in vitro biologic study of the effects of adenovirus expressing bone morphogenetic proteins (BMPs) and adenovirus expressing Sox9 on extracellular matrix metabolism by bovine nucleus pulposus cells.

OBJECTIVE: To compare the effects of recombinant adenoviral vectors expressing various BMPs (2, 3, 4, 5, 7, 8, 10, 11, 12, 13, 14, and 15) and Sox9 on extracellular matrix accumulation by bovine nucleus pulposus cells.

SUMMARY OF BACKGROUND DATA: Nucleus pulposus matrix ...

STUDY DESIGN: A biomechanical and anatomic study with human cadaveric lumbar spine.

OBJECTIVES: The purpose of this study is to examine the morphologic changes in the intervertebral foramen during flexion, extension, lateral bending, and axial rotation of the lumbar spine and to correlate these changes with the flexibility of the spinal motion segments.

SUMMARY OF BACKGROUND DATA: Previous studies showed morphologic changes in the intervertebral foramen during flexion and extension; ...

STUDY DESIGN: Destructive compression tests and finite element analyses were conducted to investigate the biomechanical strength at the graft-endplate interface in anterior cervical fusion.

OBJECTIVES: To investigate the effect of endplate thickness, endplate holes, and bone mineral density of the vertebral body on the biomechanical strength of the endplate-graft interface in an anterior interbody fusion of the cervical spine.

SUMMARY OF BACKGROUND: Subsidence of the graft into the ...

STUDY DESIGN: In vivo study of the effect of injection of osteogenic protein-1 (OP-1) on a rabbit anular needle puncture model of intervertebral disc (IVD) degeneration.

OBJECTIVE: To study radiographic, magnetic resonance imaging (MRI), biochemical, and histologic changes in the rabbit IVD after injection of OP-1 into the nucleus pulposus in a needle puncture disc degeneration model.

SUMMARY OF THE BACKGROUND DATA: Growth factors, such as OP-1, have the ability to stimulate synthesis of ...

STUDY DESIGN: A review of 66 consecutive patients at a single institution who underwent one-level anterior cervical discectomy and fusion (ACDF) with rigid anterior plate fixation with allograft or autograft.

OBJECTIVES: To address the efficacy of allograft to autograft with primary respect to fusion rate and secondary attention to risk factors and clinical outcome in patients undergoing one-level ACDF with rigid anterior plate fixation.

SUMMARY OF BACKGROUND DATA: Although autograft is ...

BACKGROUND CONTEXT: A relatively high pseudarthrosis rate is associated with multilevel anterior cervical discectomy and fusion (ACDF). Anterior plate fixation increases fusion rate in multilevel ACDF. A debate still exists between the effectiveness of allograft versus autograft in plated multilevel ACDF.

PURPOSE: To determine the efficacy of allograft versus autograft in fusion rate and clinical outcome in patients undergoing two- and three-level ACDFs with rigid anterior plate ...

STUDY DESIGN: An in vitro biomechanical study of various reconstructive techniques following decompression of the spondylotic cervical spine. OBJECTIVE.: To evaluate the biomechanical stability of anterior cervical plate fixation following three strategies of decompression for multilevel cervical spondylosis (three levels) of the cervical spine: three level discectomy, single corpectomy and discectomy, and a two-level corpectomy.

SUMMARY OF BACKGROUND DATA: The main goals of surgical ...

STUDY DESIGN: A cadaveric study was done to analyze the dimensional changes in the spinal canal and intervertebral foramen of the lumber spine with flexion and extension movements.

OBJECTIVES: To investigate the relationship between flexion and extension movements and morphologic changes in the spinal canal and the intervertebral foramen.

SUMMARY OF BACKGROUND DATA: Previous studies have reported that the dimensions of the spinal canal and the intervertebral foramen may change ...

STUDY DESIGN: Axial pullout tests using fresh cadaveric thoracolumbar vertebral bodies.

OBJECTIVES: To evaluate the effect of a new injectable calcium phosphate cement on the axial pullout strength of both revised and augmented pedicle screws in comparison with polymethyl methacrylate and in terms of injection method.

SUMMARY OF BACKGROUND DATA: Failure of pedicle screws by loosening and back out remains a significant clinical problem and is of particular concern for patients with low ...

BACKGROUND CONTEXT: Although plate fixation enhances the fusion rate in multilevel anterior cervical discectomy and fusion (ACDF), debate exists regarding the efficacy of nonplating to rigid plate fixation in one-level ACDF.

PURPOSE: To determine the efficacy of nonplating to rigid plate fixation in regards to fusion rate and clinical outcome in patients undergoing one-level ACDF with autograft.

STUDY DESIGN: A review of 69 consecutive patients who underwent one-level ACDF with autograft ...

STUDY DESIGN: A biomechanical study was performed using cadaveric cervical spine specimens.

OBJECTIVE: To determine the effect of cervical spine fusion on adjacent-level intradiscal pressure.

SUMMARY OF BACKGROUND DATA: Clinical studies have reported that patients with spinal fusion are at greater risk of pathology and early disc degeneration at adjacent levels. It is hypothesized that eliminating motion at one level leads to hypermobility and increased forces at adjacent levels, thus ...

STUDY DESIGN: Destructive biomechanical tests using fresh cadaveric thoracolumbar vertebral bodies.

OBJECTIVES: To evaluate the compression strength of human vertebral bodies injected with a new calcium phosphate (CaP) cement with improved infiltration properties for augmentation of the vertebral bodies before compression fracture and also for vertebroplasty in comparison with polymethylmethacrylate (PMMA) injection.

SUMMARY OF BACKGROUND DATA: Vertebroplasty is the percutaneous ...

STUDY DESIGN: This study correlates the mRNA and protein levels of large and small proteoglycans with the morphologic grade of degeneration.

OBJECTIVES: To investigate changes in mRNA and protein levels of aggrecan, versican, biglycan, decorin and fibromodulin in the anulus fibrosus and the nucleus pulposus at different stages of tissue degeneration.

SUMMARY OF BACKGROUND DATA: Proteoglycans are found in both the anulus fibrosus and nucleus pulposus and contribute to the hydration of the ...