Journal of neurosurgery. Spine
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The purpose of this study was to evaluate the effect of a fixed atlantoaxial angle on subaxial sagittal alignment, and that of atlantoaxial fixation on adjacent-segment motion and degeneration. ⋯ Atlantoaxial fixation in a hyperlordotic position produced kyphotic sagittal alignment after surgery in both GH and MB groups. Reduction of the atlantoaxial joint can be easily achieved through screw fixation at an optimal angle, thereby ameliorating the risk for subsequent subaxial kyphosis. Degeneration of lower adjacent segments appeared to be less with this procedure compared with using a combination of transarticular screw fixation and posterior wiring.
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Degenerative changes of the interspinous ligaments (ISLs) have generally been ignored in previous studies. Factor-related causes, the effects that these changes have on other structures within the spinal functional unit, and their relation to kinematic changes in the spine are lacking. In this study, the authors evaluated the reliability of a proposed MR imaging grading system of ISL degeneration (ISLD). They also investigated the relationship between ISLD and aging, disc/facet joint degeneration, and lumbar segmental motion. ⋯ The authors proposed a reliable and reproducible grading system that may be used to investigate spinal kinematics in association with ISLD. The authors' findings illustrated the distribution of ISLD grades. The most severe grade occurred primarily in elderly patients. Mobility decreased in the most severe grade; therefore, the stage of ISLD should be taken into consideration when evaluating spinal stability.
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The prognosis in patients with a distant spinal metastasis from the lung is dismal. The role of radical surgery in such cases has been questioned because of the excessive morbidity, blood loss, and operative time as well as the tumor's extreme malignancy. The purpose of this study was to evaluate the surgical results and the prognosis associated with radical surgery for lung cancer metastasis to the spine in carefully selected patients and to clarify whether there is an indication for radical surgery such as total en bloc spondylectomy (TES) in lung cancer metastasis. ⋯ Total en bloc spondylectomy has been shown to be associated with excessive morbidity, blood loss, and operative time; however, the procedure is becoming less invasive. The authors conclude that TES is appropriate in selected cases with controllable primary lung cancer, localized spinal metastasis, and no visceral metastasis. In such patients, improvement in the prognosis can be expected after TES. However, even in selected cases and with skilled surgical technique, the complication rate remains high. Total en bloc spondylectomy should be performed after a thorough discussion of the risks and benefits.
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This study was conducted to assess the in vivo safety and accuracy of percutaneous lumbar pedicle screw placement using the owl's-eye view of the pedicle axis and a new guidance technology system that facilitates orientation of the C-arm into the appropriate fluoroscopic view and the pedicle cannulation tool in the corresponding trajectory. ⋯ The owl's-eye technique of coaxial pedicle imaging with the C-arm fluoroscopy, facilitated by NeuroVision, is a safe and accurate means by which to place percutaneous pedicle screws for degenerative conditions of the lumbar spine. This is the largest series reported to use the oblique or owl's-eye projection for percutaneous pedicle screw insertion. The accuracy of percutaneous screw insertion with this technique meets or exceeds that of other reported clinical series or techniques.
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Thoracic pedicle screw instrumentation is often indicated in the treatment of trauma, deformity, degenerative disease, and oncological processes. Although classic teaching for cervical spine constructs is to bridge the cervicothoracic junction (CTJ) when instrumenting in the lower cervical region, the indications for extending thoracic constructs into the cervical spine remain unclear. The goal of this study was to determine the role of ligamentous and facet capsule (FC) structures at the CTJ as they relate to stability above thoracic pedicle screw constructs. ⋯ When stopping thoracic constructs at T-1, care should be taken to preserve the SSL/ISL complex to avoid destabilization of the supra-adjacent CTJ, which may manifest clinically as proximal-junction kyphosis. In an analogous fashion, if a T-1 laminectomy is required for neural decompression or surgical access, consideration should be given to extending instrumentation into the cervical spine. Facet capsule disruption, as might be encountered during T-1 pedicle screw placement, may not be an acutely destabilizing event, due to the interaction of the C7–T1 facet joints with T-1 instrumentation.