広範脊柱管狭窄症

Background/Objectives: Indirect decompression through restoration of disc and foraminal height with a large lateral interbody cage has been advocated for selected patients, but its efficacy in a large series remains unproven. In this retrospective study, we evaluated the clinical and radiographic results of indirect decompression achieved by posterior longitudinal ligament (PLL) ligamentotaxis in minimally invasive oblique lateral interbody fusion (MIS-OLIF) performed without posterior decompression. Methods: We retrospectively reviewed 236 consecutive patients treated for single- or two-level degenerative lumbar disease (November 2019-May 2025); clinical follow-up of at least 24 months was available in 181 patients. Visual analogue scale (VAS) scores and radiographic parameters-disc height, foraminal height, foraminal area, spinal canal diameter and cross-sectional area (CSA) of the thecal sac-were compared before and after surgery, and extension ratios were correlated with preoperative values. Results: Clinical scores improved significantly. All radiographic parameters increased substantially: disc height +49.1%, foraminal height +33.7%, foraminal area +44.5%, canal diameter +37.4% and CSA +36.2%. Extension ratios were inversely correlated with preoperative values. Six patients (2.5%) required additional posterior decompression. The slippage subgroup showed greater radiographic gains than the stenosis subgroup. Conclusions: MIS-OLIF without posterior decompression significantly enlarged the foramen and spinal canal; reduction in disc bulging and PLL ligamentotaxis may contribute to this effect, with greater improvement in more severely degenerated, overtly slipped segments. Careful patient selection remains essential, and prospective comparative studies with longer follow-up are needed.

Ponticulus posticus (PP) is a bony bridge arising from the posterior arch of C1 toward the superior articular process or lateral mass; when complete, it forms an arcuate foramen over the C1 vertebral artery (VA) groove and may convert the VA path into an osseous canal. This anatomy can narrow the usual corridor for C1 lateral mass screw (LMS) insertion. We report a 68-year-old man who sustained an upper cervical cord injury (ASIA Impairment Scale grade [AIS] B) after a fall. Computed tomography (CT) revealed continuous ossification of the posterior longitudinal ligament and anterior longitudinal ligament from C2 to T1, and magnetic resonance imaging showed canal stenosis due to a retro-odontoid pseudotumor with intramedullary signal change. Dynamic flexion radiograph demonstrated an atlas-dens interval of 5.6 mm and a space available for the spinal cord of 15.5 mm, while three-dimensional computed tomographic angiography identified bilateral complete PP with an aberrant VA course and no symptoms of vertebrobasilar insufficiency. After C1 laminectomy, the arcuate bony bridge was microsurgically unroofed with a 3-mm high-speed burr, enabling direct visualization and protection of the VA with neurosurgical sheets and a Penfield dissector; unroofing was complete on the left and partial on the right based on the bony bridge morphology and the VA exit point. An intraoperative navigation system confirmed screw entry points and trajectories, allowing placement of C1 screws. Immediate postoperative CT confirmed appropriate screw positions. Postoperative vascular imaging was not performed. At three months, the patient's neurological status improved to AIS C, which indicates motor-incomplete spinal cord injury, with no implant-related complications. In bilateral complete PP, the risk of VA injury with C1 LMS has led to divergent recommendations ranging from avoidance to conditional use with protective techniques. Microsurgical unroofing placed the VA under direct visualization and protection, and navigation verified a controlled corridor, supporting intraoperative adjustments in complex C1-2 anatomy. In this setting, microsurgical unroofing with navigation permitted C1 LMS placement under direct VA visualization and protection and may be a reasonable option when a controlled corridor can be created in selected patients.

PURPOSE: This study aims to establish a comprehensive protocol for assessing the morphometric parameters of the cervical vertebral canal using Magnetic Resonance Imaging (MRI) and to evaluate the interobserver reliability of these measurements. METHODS: A descriptive study was conducted to evaluate the diameter and area of the cervical vertebral canal through MRI scans of 20 patients. Two independent observers performed the measurements, and interobserver reliability was assessed using Intraclass Correlation Coefficients (ICC). RESULTS: The study detailed an effective method for evaluating both the diameter and area of the cervical vertebral canal, demonstrating excellent interobserver reproducibility for diameter measurements (ICC > 0.969) and good reproducibility for area measurements (ICC > 0.893). CONCLUSION: This protocol provides a standardized approach for measuring the cervical vertebral canal parameters, enhancing the evaluation of stenosis, and supporting precise clinical decision-making. The protocol is clear, reproducible, and adaptable for use in other research settings and clinical practices.

Endoscopic spine surgery enables targeted neural decompression with the least amount of tissue disruption to paraspinal structures compared to other spine surgery techniques. Though with minimal visualization, endoscopic spine surgery can be challenging. This article presents a stepwise overview of three key uniportal lumbar endoscopic techniques: interlaminar microdiscectomy, interlaminar laminectomy, and transforaminal microdiscectomy. Through integrated operative footage, the videos demonstrate indications, portal trajectory, and critical anatomic landmarks unique to each approach. The interlaminar microdiscectomy technique is illustrated for median and paramedian disc herniations, emphasizing safe ligamentum flavum separation, dural protection, and direct fragment removal under endoscopic visualization. The interlaminar laminectomy segment details the management of central and lateral recess stenosis, highlighting stepwise bone removal, decompression of traversing and exiting roots, and controlled hemostasis within a limited corridor. The transforaminal microdiscectomy sequence demonstrates access through Kambin's triangle, foraminoplasty, and targeted fragment excision without violating the spinal canal. Operative tips focus on portal alignment, irrigation control, and avoidance of nerve injury, supplemented by discussion of ergonomic hand positioning and intraoperative troubleshooting. Together, these video demonstrations provide a comprehensive visual reference for surgeons transitioning to endoscopic lumbar surgery. By standardizing procedural steps and emphasizing anatomical orientation, this method article aims to enhance reproducibility, expand technical proficiency, and promote the safe adoption of endoscopic decompression for lumbar disc and canal pathology.

BACKGROUND: Congenital cervical spine stenosis is an anatomical narrowing of the cervical spine canal, an aberrant anatomy, which can predispose patients to a wide variety of spinal injuries in undiagnosed individuals, even in the setting of minor trauma. Life-threatening injuries with premature career endings are not uncommon among athletes with undiagnosed congenital cervical stenosis sustaining cervical trauma and are well reported in many news outlets. Unfortunately, no clear consensus regarding diagnostic workup and universal guidelines regarding return to play exist. A similar imbroglio exists over criteria and parameters used to screen and diagnose the condition, as well as the demographics and epidemiology of congenital cervical spine stenosis due to limited evidence. PURPOSE: The goal of this retrospective study is to investigate the prevalence of congenital cervical spine stenosis by race. STUDY DESIGN: Large level 1 trauma center retrospective cross-sectional study PATIENT SAMPLE: A total of 381 trauma patients with unremarkable cervical spine CAT scan from 01/01/2013-12/31/2023 OUTCOME MEASURES: The mid-sagittal canal diameter (SCD) and the interpedicular distance (IPD) were measured from C3-T1 using criteria established by Bajwa, SCD < 13 mm and IPD < 23 mm as cut points for cervical spine stenosis, with sensitivity and specificity of 88-100% at each cervical vertebral body. METHODS: A total of 797 patients were reported in the registry; 416 met exclusion criteria. ßDemographic variables, such as age, gender and race, were collected. All patients with a history of cervical spine injury, previous surgeries, and pre-existing anomalies, including lesions, mass, deformity and technical artifact, were excluded. The mid-sagittal canal diameter (SCD) and the interpedicular distance (IPD) were measured from C3-T1. RESULTS: Three hundred and eighty-one (381) patients met inclusion criteria: 306 (81%) were White, 70 (19%) were Black, 3 (0.78) identified as Asian, and 2 (0.52) were American Indian. In the Asian and American Indian groups no cervical level met the criteria of stenosis as defined by an SCD <13 mm and IPD <23 mm. For both the White and Black participant groups, C3-C4 was found to have the narrowest canal diameter with an average SCD of 13.57 ± 1.63and IPD 21.83 ± 1.53. The White participant group prevalence was 15.4% at C3-C4, compared to 21.4% among the Black participant group. CONCLUSION: This study revealed a high prevalence of congenital cervical stenosis within a trauma population with a higher prevalence within the Black participant group. Additionally, C3-C4 was found the most commonly affected level, as opposed to previous reports at C5. Providers must remain vigilant for stenosis in at-risk populations.