72 research outputs found

    Posterior Trans-Dural Repair of Iatrogenic Spinal Cord Herniation after Resection of Ossification of Posterior Longitudinal Ligament

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    Iatrogenic spinal cord herniation is a rare complication following spinal surgery. We introduce a posterior trans-dural repair technique used in a case of thoracic spinal cord herniation through a ventral dural defect following resection of ossification of the posterior longitudinal ligament (OPLL) in the cervicothoracic spine. A 51-year-old female was suffering from paraplegia after laminectomy alone for cervicothoracic OPLL. Magnetic resonance imaging revealed a severely compressed spinal cord with pseudomeningocele identified postoperatively. Cerebrospinal fluid leak and iatrogenic spinal cord herniation persisted despite several operations with duroplasty and sealing agent. Finally, the problems were treated by repair of the ventral dural defect with posterior trans-dural duroplasty. Several months after surgery, the patient could walk independently. This surgical technique can be applied to treat ventral dural defect and spinal cord herniation

    Accuracy of Free Hand Pedicle Screw Installation in the Thoracic and Lumbar Spine by a Young Surgeon: An Analysis of the First Consecutive 306 Screws Using Computed Tomography

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    Study DesignA retrospective cross-sectional study.PurposeThe purpose of this study is to evaluate the accuracy and safety of free-hand pedicle screw insertion performed by a young surgeon.Overview of LiteratureFew articles exist regarding the safety of the free-hand technique without inspection by an experienced spine surgeon.MethodsThe index surgeon has performed spinal surgery for 2 years by himself. He performed fluoroscopy-assisted pedicle screw installation for his first year. Since then, he has used the free-hand technique. We retrospectively reviewed the records of all consecutive patients undergoing pedicle screw installation using the free-hand technique without fluoroscopy in the thoracic or lumbar spine by the index surgeon. Incidence and extent of cortical breach by misplaced pedicle screw was determined by a review of postoperative computed tomography (CT) images.ResultsA total of 36 patients received 306 free-hand placed pedicle screws in the thoracic or lumbar spine. A total of 12 screws (3.9%) were identified as breaching the pedicle in 9 patients. Upper thoracic spine was the most frequent location of screw breach (10.8%). Lateral breach (2.3%) was more frequent than any other direction. Screw breach on the right side (9 patients) was more common than that on the left side (3 patients) (p<0.01).ConclusionsAn analysis by CT scan shows that young spine surgeons who have trained under the supervision of an experienced surgeon can safely place free-hand pedicle screws with an acceptable breach rate through repetitive confirmatory steps

    Megahertz-wave-transmitting conducting polymer electrode for device-to-device integration

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    The ideal combination of high optical transparency and high electrical conductivity, especially at very low frequencies of less than the gigahertz (GHz) order, such as the radiofrequencies at which electronic devices operate (tens of kHz to hundreds of GHz), is fundamental incompatibility, which creates a barrier to the realization of enhanced user interfaces and ‘device-to-device integration.’ Herein, we present a design strategy for preparing a megahertz (MHz)-transparent conductor, based on a plasma frequency controlled by the electrical conductivity, with the ultimate goal of device-to-device integration through electromagnetic wave transmittance. This approach is verified experimentally using a conducting polymer, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), the microstructure of which is manipulated by employing a solution process. The use of a transparent conducting polymer as an electrode enables the fabrication of a fully functional touch-controlled display device and magnetic resonance imaging (MRI)-compatible biomedical monitoring device, which would open up a new paradigm for transparent conductors. © 2019, The Author(s

    Primary Intramedullary Neuroblastoma in Adult

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    Primary neuroblastoma in the central nervous system(CNS) is unusual tumor in adult, and primary intramedullary neuroblastoma is extremely rare. The authors report a case of 36-year-old woman presenting with pain in the right anterior chest wall and weakness of the right lower extremity. An upper thoracic intraspinal mass was revealed on magnetic resonance image. On operation, the demarcation plane of the tumor was good and enabled a total removal of the subpially located intramedullary mass. Histopathological examination revealed neuroblastoma. After surgery with whole spinal irradiation, the patient was followed up for one year. There was no evidence of local recurrence radiologically and clinically. However fifteen months after the surgery, multiple metastases to the breast, lung, Iioer and brain occurred

    Early Outcome of Posterior Cervical Endoscopic Discectomy: An Alternative Treatment Choice for Physically/Socially Active Patients

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    Anterior cervical discectomy and fusion (ACDF) is currently the standard treatment for cervical disc disease. Some patients wish to be treated with a less invasive method, because of their social/physical situations. Here we present one method of treatments for socially/physically active patients. Three patients had triceps weakness and mild posterior neck pain. The offending lesions were at the C6-7 level. All were middle-aged soldiers with families. If conventional ACDF were performed, they would have to retire from the military according to the regulation. They had to be able to perform military drills after the treatment if they were going to be able to keep their jobs. Because of their social/physical situations, all wanted to choose method with that they could treat the disease and keep their jobs. For these reasons, the posterior cervical endoscopic discectomies were performed. Ruptured fragments were successfully removed in all. The arm pain improved by more than 90% in two patients by 7 days and in the other patient by 2 months, respectively (excellent outcome by Macnab's criteria). None of the operations caused instability. All of the patients are currently able to successfully perform their military drills without difficulty. The posterior cervical endoscopic discectomy may be a promising alternative for the physically/socially active patients

    Transforaminal Epidural Steroid Injection for Lumbosacral Radiculopathy: Preganglionic versus Conventional Approach

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    OBJECTIVE: The present study was undertaken to evaluate the effectiveness of transforaminal epidural steroid injection (TFESI) with using a preganglionic approach for treating lumbar radiculopathy when the nerve root compression was located at the level of the supra-adjacent intervertebral disc. MATERIALS AND METHODS: The medical records of the patients who received conventional TFESI at our department from June 2003 to May 2004 were retrospectively reviewed. TFESI was performed in a total of 13 cases at the level of the exiting nerve root, in which the nerve root compression was at the level of the supra-adjacent intervertebral disc (the conventional TFESI group). Since June 2004, we have performed TFESI with using a preganglionic approach at the level of the supra-adjacent intervertebral disc (for example, at the neural foramen of L4-5 for the L5 nerve root) if the nerve root compression was at the level of the supra-adjacent intervertebral disc. Using the inclusion criteria described above, 20 of these patients were also consecutively enrolled in our study (the preganglionic TFESI group). The treatment outcome was assessed using a 5-point patient satisfaction scale and by using a VAS (visual assessment scale). A successful outcome required a patient satisfaction scale score of 3 (very good) or 4 (excellent), and a reduction on the VAS score of > 50% two weeks after performing TFESI. Logistic regression analysis was also performed. RESULTS: Of the 13 patients in the conventional TFESI group, nine showed satisfactory improvement two weeks after TFESI (69.2%). However, in the preganglionic TFESI group, 18 of the 20 patients (90%) showed satisfactory improvement. The difference between the two approaches in terms of TFESI effectiveness was of borderline significance (p = 0.056; odds ratio: 10.483). CONCLUSION: We conclude that preganglionic TFESI has the better therapeutic effect on radiculopathy caused by nerve root compression at the level of the supra-adjacent disc than does conventional TFESI, and the difference between the two treatments had borderline statistical significance

    Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

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    Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p&lt;0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (&lt;1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (&lt;1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

    Efficiency of lead aprons in blocking radiation − how protective are they?

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    Background: Despite the firmly established occupational risk of exposure to X-rays, they are used extensively in spine surgeries. Shielding by lead aprons is the most common protective practice. We quantified the level of their radiation blocking ability in a real-life setting. Methods: Single-center, prospective, randomized study of adult patients with degenerative lumbar disorders, scheduled to undergo posterior lumbar interbody fusion. Instrumentation was performed in either a robot-assisted, minimally invasive approach (RO) or a conventional, fluoroscopically-assisted, open approach (FA). Outcome measures included the quantitative measurement of the surgeon’s actual exposure to radiation, as recorded by thermo-luminescent dosimeters (TLD) worn both above and under the 0.5 mm thyroid and trunk lead protectors. Findings: Sixty four patients were included in this study, 34 in the RO cohort and 30 in the FA cohort. The radiation blocked by the aprons, represented as the ratio of the under-apron to above-apron TLDs, averaged 37.1% (range 25.4–48.3%, 95% confidence interval between 30.6–43.6%). In the RO cohort, the average per-screw radiation dose and time were 51.9% and 73.7% lower, respectively, than the per screw exposure in the FA cohort. Interpretation: The 0.5 mm lead aprons blocked just over one third of the radiation scattered towards the surgeon. Use of robotic-guidance in a minimally invasive approach provided for a reduction of 62.5% of the overall radiation the surgeon was exposed to during open conventional approach. We conclude that reduced radiation use (e.g. by using robotic guidance) is a more effective strategy for minimizing exposure to radiation than reliance on protection by lead aprons, and recommend utilization of practices and technologies that reduce the surgical team’s routine exposure to X-rays

    Bicortical Screw Purchase at Upper Instrumented Vertebra (UIV) Can Cause UIV Fracture After Adult Spinal Deformity Surgery: A Finite Element Analysis Study

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    Objective To examine the biomechanical stress distribution at the upper instrumented vertebra (UIV) according to unicortical- and bicortical purchase model by finite element analysis (FEA). Methods A T8 to Sacrum with implant finite element model was developed and validated. The pedicle screws were unicortically or bicortically inserted from T10 to L5, and each model was compared and the von Mises (VM) yield stress of T10 was calculated. According to the motion (flexion, extension, lateral bending, and axial rotation) of spine, boundary condition values were set as 15°, 15°, 10°, 4°. Results Although the 2 stress values did not show a significant difference between the unicortical- and bicortical purchase models in the flexion and extension, bicortical purchase model showed a larger stress distribution. However, the asymmetric behavior was significantly greater in the case of lateral bending (0.802 MPa vs. 0.489 MPa) and the rotation (5.545 MPa vs. 4.905 MPa). The greater stress was observed on the spinal body surface abutting the implanted screw. Although the maximum stress was observed around the implanted screw in the bicortical purchase model under axial loading, the VM stress of both models was not significantly different. Conclusion Bicortical purchase model showed a larger stress distribution than the unicortical model, especially in the case of lateral bending and the rotation behavior. Our biomechanical simulation by FEA indicates that bicortical fixation at UIV can be a risk factor for early UIV compression fracture after adult spinal deformity surgery

    Subsidence as of 12 months after single-level anterior cervical inter-body fusion. Is it related to clinical outcomes?

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    Background Subsidence is a frequent phenomenon in the interbody fusion process in patients with anterior cervical discectomy and fusion (ACDF). There is little evidence of whether subsidence in the cervical spine has any impact on clinical outcomes. Objectives The purpose of this study is to investigate the correlation of subsidence and clinical outcomes after ACDF and to consider reasons subsidence might not cause unfavorable clinical outcomes. Methods A total of 158 consecutive patients who underwent single-level ACDF were included. The patients were divided into a subsidence group (S-group) and a no subsidence group (N-group), with subsidence defined as a decrease by ≥3 mm in total intervertebral height (TIH). We analyzed outcomes resulting from subsidence, particularly focusing on clinical outcomes and subsequent global and segmental kyphosis using a repeated measure analysis of variance (RM-ANOVA). Results Subsidence occurred in 74 patients (46.8 %) as of a 12-month follow-up. The S-group included 58.6 % with a stand-alone cage for interbody fusion (p=0.002). Clinical outcomes improved significantly over time (neck pain, RM-ANOVA: F(1.3, 205)=125.1, p<0.001; arm pain, RM-ANOVA: F(1.3, 203)=290.8, p<0.001). There was no significant difference in interaction with subsidence and clinical outcomes between the S- and Ngroup (neck pain, RM-ANOVA: F(2,153)=1.04, p=0.356, partial η2 = 0.229; arm pain, RM-ANOVA: F(2,153)=0.56, p=0.571, partial η2 =0.142). Segmental angle increased in both groups over time and showed a statistically significant difference between the S- and N-groups (RM-ANOVA: F(3,143)=6.148, p=0.001, partial η2 =0.959). Although, global cervical angle decreased generally and displayed no statically significant difference between the S- and N-group (RM-ANOVA: F(3,119) = 2.361, p=0.075, partial η2 =0.056). Conclusions Radiographic subsidence after ACDF occurred in 46.8 % patients as of 12 months after the single-level ACDF. The lack of correlation between bad clinical outcome and radiographic subsidence may be due to segmental kyphosis, preserved posterior height, and maintaining the global cervical angle.OAIID:oai:osos.snu.ac.kr:snu2015-01/102/0000004226/13ADJUST_YN:NEMP_ID:A079510DEPT_CD:801CITE_RATE:1.766FILENAME:acta neurochir-wien-2015_lee_subsidence as of 12 months after singlelevel anterior cervical interbody fusion.pdfDEPT_NM:의학과SCOPUS_YN:YCONFIRM:
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