Novel Minimal Invasive Surgical Techniques for the Treatment of Segmental-Lateral Pathologic Lesions of the Spine (original) (raw)
Related papers
2009
Study Design. A morphometric analysis, using magnetic resonance imaging (MRI) studies of the lumbar spine. Objective. To identify the anatomic position of the ventral root and the retroperitoneal vessels in relation to the vertebral body in normally aligned and deformed spines. Summary of Background Data. The lateral approach to the lumbar spine is a relatively new method for performing interbody fusions. In contrast to the standard open anterior approach with direct vision of the operative field, the lateral approach uses expandable retractors that are positioned under fluoroscopic guidance. Risks of this technique include injury to the exiting nerve root and retroperitoneal vessels. Methods. One hundred lumbar spine MRI studies were reviewed from patients treated for various spinal pathologies. The measured intervertebral segments were divided into 3 groups: group 1 (n ϭ 247), normally aligned vertebrae and disc spaces; group 2 (n ϭ 18), degenerative spondylolisthetic segments; and group 3 (n ϭ 19), segments from the apex of degenerative lumbar scoliosis. Axial MR images were used to measure: the vertebral endplate anterior-posterior (AP) diameter, the overlap between the ventral root and the posterior margin of the vertebra, and the overlap between the retroperitoneal large vessels and the anterior edge of the vertebra. Results. The overlap between the adjacent neuro-vascular structures and the vertebral body endplate gradually increased from L1-L2 to L4-L5. The maximal overlap, at the L4-L5 level reached 87% resulting in a relatively narrow corridor for performing the operative procedure. Alteration in the anatomic location of the nerve root and the retroperitoneal vessels, in Group 3 (scoliosis) further decreased the safe corridor. Conclusion. The safe corridor for performing the discectomy and inserting the intervertebral cage narrows from L1-L2 to the L4-L5 level. This corridor is further narrowed with rotatory deformity of the spine. Using the preoperative MRI to assess the relative position of the adjacent neuro-vascular structures in relation to the lower vertebra's endplate at each level is recommended.
Spinal Instrumentation after Complete Resection of the Last Lumbar Vertebra
Spine, 2011
Study Design. Human cadaveric ilio-lumbosacral spines were tested in an in vitro biomechanical fl exibility experiment to investigate the biomechanical stability provided by four different types of spinal reconstruction techniques after spondylectomy of the L5 vertebral body. Objective. To compare the biomechanical stability provided by four reconstruction methods after L5 spondylectomy. Summary of Background Data. Clinical studies have shown that total spondylectomy of the L5 vertebral body presents a challenging scenario for spinal reconstruction. Biomechanical studies on spinal reconstruction after total spondylectomy have been performed at the thoracolumbar junction. However, there have been no biomechanical studies after L5 spondylectomy. Methods. Seven cadaveric lumbosacral spines (L2-S1) with intact ilium were used. After intact testing, spondylectomy of the L5 vertebra was performed and the spine was reconstructed using an expandable cage for anterior column support. Supplementary fi xation was performed as a sequential order of: (1) bilateral pedicle screws at L4-S1 (SP), (2) anterior plate and bilateral pedicle screws at L4-S1 (ASP), (3) bilateral pedicle screws at L3-S1 and iliac screws (MP), and (4) anterior plate at L4-S1, bilateral pedicle screws at L3-S1 and iliac screws (AMP). Range of motion (ROM) for each construct was obtained by applying pure moments in fl exion, extension, lateral bending, and axial rotation. Results. In fl exion, extension and lateral bending all the instrumented constructs signifi cantly decreased (P < 0.05) the range of motion (ROM) compared to intact. In axial rotation, only the circumferential support constructs (ASP, AMP) provided signifi cantly decreased (P < 0.05) ROM, whereas posterior instrumentations alone (SP, MP) were comparable to intact spines.
Anatomy and Examination of the Spine
Neurologic Clinics, 2007
A review of the anatomy of the spine in a few pages must, by necessity, be abridged. This article concentrates on clinically relevant anatomy. For a more expansive discussion, the reader is referred to the most recent edition of Gray's anatomy .
Journal of Spine, 2015
Surgeries for Lumbar Spinal Stenosis (LSS) aim at decompressing spinal nerves and relieving symptoms of radiculopathy or myelopathy. Frequently after surgery, stenosis may progress in adjacent spinal segments, but the etiology of adjacent segment degeneration is still unclear. It is hypothesized that surgical approaches for LSS may alter the normal biomechanics of adjacent segments, eventually contributing to the development of stenosis. This study investigated implications of established decompressive surgical approaches on adjacent segments biomechanics.
The Spine Journal, 2002
Background context: Bilateral laminotomy has been proposed as an alternative to laminectomy for decompression of lumbar spinal stenosis. Preservation of the posterior midline ligaments with laminotomy is presumed to maintain spinal segment stability. There have been no previous studies that directly compare the amount of destabilization and increase in disc pressures between the two procedures. Purpose: To quantify spinal segmental instability caused by bilateral laminotomy and laminectomy, and to compare the central and peripheral intradiscal pressures after the two procedures. Study design/setting: Mechanical testing of the lumbar motion segments of calf spines. Methods: Nine fresh calf spines were tested under flexion, extension, lateral bending and axial rotation, intact first, then after laminotomy and laminectomy at the level of L4-L5. Four miniature pressure transducers were implanted in the central and peripheral disc at L4-L5 to measure intradiscal pressures. Three-dimensional motion was measured with motion analysis system. Results: Comparing with bilateral laminotomy, laminectomy showed significant increase in segmental motion at the surgical level in flexion (16%, p Ͻ .05), extension (14%, p Ͻ .04) and right axial rotation (23%, p Ͻ .03). In flexion, the stress at the anterior annulus increased a nonsignificant 20% after laminotomy, but significant 130% after laminectomy (p Ͻ .02). In the intact spine, the posterolateral annulus experienced the highest stress with lateral bending to the same side when compared with other loading directions. This stress remained unchanged after laminotomy but increased 9% after laminectomy (p Ͻ .06). In rotation, axial intradiscal stresses were evenly distributed and unchanged after each procedure. Conclusions: Laminectomy causes more destabilization of a spinal motion segment than laminotomy and significantly increases disc stress in the anterior annulus.
Anatomic Considerations in Spine Surgery
Contemporary Spine Surgery, 2000
LEARNING OBJECTIVES-By the time the reader finishes this lesson, he or she should be able to: 1. Define the bony landmarks on the external surface of the occipital bone. 2. Describe the posterior instrumentation in the lower cervical spine. 3. Identify the most vulnerable and important structures during anterior dissection and decompression. CATEGORY-Spinal Anatomy KEY WORDS-vertebral body, lateral mass, pedicle, transverse formina, nuchal lines This continuing education activity is intended for orthopedic surgeons and other physicians with an interest in spine surgery.
Spine Surgery and Related Research
2019
Introduction: This study aimed to compare the clinical and radiological results of transforaminal lumbar interbody fusion (TLIF) with a boomerang-shaped cage and traditional posterior lumbar interbody fusion (PLIF) according to fused level and elucidate whether TLIF could replace PLIF at all lumbar levels. Methods: The study investigated 128 patients with lumbar spondylolisthesis who underwent a single-level TLIF or traditional PLIF. Intraoperative blood loss, operative time, and recovery rate were analyzed. Percent slip, disc height, and local lordosis at the fused level were measured using X-ray images from preoperation to the final follow-up. Results: No significant differences in recovery rate were observed at any level. The operative time and intraoperative blood loss were significantly less in the TLIF group at the L4/5 and L5/S1 levels. There were no significant differences in disc height or local lordosis at the L3/4 and L4/5 levels, and a satisfactory level of maintenance a...