Spine
-
Comparative Study
Biomechanical analysis of posterior fixation techniques in a 360 degrees arthrodesis model.
A biomechanical study to assess the ability of posterior fixation techniques to stabilize a functional spine unit (FSU) after insertion of an anterior load-sharing device. ⋯ Using a load-sharing interbody implant, translaminar facet screws are equivalent to bilateral pedicle screws in resisting motion in all three planes. Translaminar facet screws and bilateral pedicle screws offer greater stabilization in all three planes compared with unilateral pedicle screws and a single plate.
-
Comparative Study
Does anterior plating of the cervical spine predispose to adjacent segment changes?
In a human cadaveric model, the effects of plate supplementation on the mechanical behaviors of adjacent segments were investigated. ⋯ Intradiscal pressures and intervertebral motion at the adjacent levels are not significantly affected by the instrumented anterior fusion. The clinically observed degenerative change at adjacent segments in the cervical spine is more likely to be attributed to natural progression of the spondylotic process as opposed to biomechanical effect of the instrumentation or fusion.
-
Comparative Study
Human anulus fibrosis and nucleus pulposus cells of the intervertebral disc: effect of degeneration and culture system on cell phenotype.
Human intervertebral disc cells were harvested from patients with adolescent idiopathic scoliosis (AIS) and from donors with degenerative disc disease. Anulus fibrosis (AF) was separated from nucleus pulposus (NP), and cells were cultured separately in two different cell culture models. ⋯ These results provide a better understanding of how the phenotype of human healthy and degenerative disc cells is influenced by in vitro expansion. This may be useful for future tissue engineering purposes.
-
Comparative Study
The learning curve associated with thoracoscopic spinal instrumentation.
Consecutive case prospective radiographic and medical record review. ⋯ The learning curve associated with thoracoscopic spinal instrumentation appears to be acceptable. Significant differences were noted in operating time and percent curve correction after 28 cases. The complication rates remained stable throughout the surgeon's experience.
-
Postoperative outcomes of cervical pedicle screw (CPS) placement were evaluated. The screws were inserted in degenerative vertebrae using anatomic landmarks. ⋯ The deviation rate of CPS placement using anatomic landmarks was higher than anticipated, although no serious complications were encountered. Refinement of the technique (e.g., using a computer-assisted navigation system) is strongly recommended.