Objectives. Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. Methods. CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1
Many studies have investigated the kinematics of the lumbar spine and the morphological features of the lumbar discs. However, the segment-dependent immediate changes of the lumbar intervertebral space height during flexion-extension motion are still unclear. This study examined the changes of intervertebral space height during flexion-extension motion of lumbar specimens. First, we validated the accuracy and repeatability of a custom-made mechanical loading equipment set-up. Eight lumbar specimens underwent CT scanning in flexion, neural, and extension positions by using the equipment set-up. The changes in the disc height and distance between adjacent two pedicle screw entry points (DASEP) of the posterior approach at different lumbar levels (L3/4, L4/5 and L5/S1) were examined on three-dimensional lumbar models, which were reconstructed from the CT images.Objectives
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To employ a simple and fast method to evaluate those patients with neurological deficits and misplaced screws in relatively safe lumbosacral spine, and to determine if it is necessary to undertake revision surgery. A total of 316 patients were treated by fixation of lumbar and lumbosacral transpedicle screws at our institution from January 2011 to December 2012. We designed the criteria for post-operative revision scores of pedicle screw malpositioning (PRSPSM) in the lumbosacral canal. We recommend the revision of the misplaced pedicle screw in patients with PRSPSM = 5′ as early as possible. However, patients with PRSPSM < 5′ need to follow the next consecutive assessment procedures. A total of 15 patients were included according to at least three-stage follow-up.Objectives
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