• Journal of Korean Neurosurgical Society
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• 제38권1호
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• pp.77-79
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• 2005

We report a case of early stress fracture of the pelvic ring following an extension of a multilevel instrumented lumbosacral fusion in an osteopenic female. Surgeons should be aware of possibilities of pelvic complications in osteopenic patients with lumbosacral arthrodesis and should take care when harvesting iliac bone graft.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.664-667
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• 2008

Since the advent of pedicle screw fixation system, posterior spinal fusion has markedly increased This intemal fixation system has been reported to enhance the fusion rates, thereby becoming very popular procedure in posterior spinal arthrodesis. Although some previous studies have shown the complications of spinal instruments removal, i.e. loss of correction and spinal collapse in scoliosis or long spine fusion patients, there has been no study describing the benefit or complications in lumbar spinal fusion surgery of one or two level. In order to clarify the effect of removal of instruments on mechanical motion profile, we simulated a finite element model of instrumented posterolateral fused lumbar spine model, and investigated the change of mechanical motion profiles after the removal of instrumentation.

• Journal of Korean Neurosurgical Society
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• 제62권6호
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• pp.700-711
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• 2019

Objective : The treatment of multiple thoracolumbar spine fractures according to fracture continuity has rarely been reported. Herein we evaluate the clinical features and outcomes of multiple thoracolumbar fractures depending on continuous or noncontinuous status. Methods : From January 2010 to January 2016, 48 patients with acute thoracic and lumbar multiple fractures who underwent posterior fusion surgery were evaluated. Patients were divided into two groups (group A : continuous; group B : noncontinuous). We investigated the causes of the injuries, the locations of the injuries, the range of fusion levels, and the functional outcomes based on the patients' general characteristics. Results : A total of 48 patients were enrolled (group A : 25 patients; group B : 23 patients). Both groups had similar pre-surgical clinical and radiologic features. The fusion level included three segments (group A : 4; group B : 5) or four segments (group A : 19; group B : 5). Group B required more instrumented segments than did group A. Group A scored 23.5 and group B scored 33.4 on the Korean Oswestry Disability Index (KODI) at the time of last follow-up. In both groups, longer fusion was associated with worse KODI score. Conclusion : In this study, due to the assumption of similar initial clinical and radiologic features in both group, the mechanism of multiple fractures is presumed to be the same between continuous and noncontinuous fractures. The noncontinuous fracture group had worse KODI scores in long-term follow-up, thought to be due to long fusion level. Therefore, we recommend minimizing the number of segments that are fused in multiple thoracolumbar and lumbar fractures when decompression is not necessary.

• Journal of Yeungnam Medical Science
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• 제20권2호
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• pp.160-168
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• 2003

요추부 척추에 기구를 시술한 유한요소 복합체 모델을 이용하여 제 4-5 요추간판에 대한 해석을 수행한 결과, 근육의 작용을 케이블과 케이블 가이드로써 단순화 모사한 follower 하중에서 수직하중인 경우보다 높은 압축력을 나타내어 더욱 안정함을 보였고 불안정성의 원인이 되는 전단력과 굽힘모멘트의 발생은 미미하였다. 장분절 고정에 의한 인접 분절에 전단력이 증가됨을 실험적으로 보였는데, 이는 장분절 고정이 퇴행성 변화 촉진에 기여할 것으로 추정된다.

• Journal of Korean Neurosurgical Society
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• 제64권3호
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• pp.437-446
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• 2021

Objective : To investigate the radiographic characteristics of the uppermost instrumented vertebrae (UIV) and UIV+1 compression fractures that are predictive of revision surgery following long-segment spinal fixation. Methods : A total 27 patients who presented newly developed compression fracture at UIV, UIV+1 after long segment spinal fixation (minimum 5 vertebral bodies, lowest instrumented vertebra of L5 or distal) were reviewed retrospectively. Patients were divided into two groups according to following management : revisional surgery (group A, n=13) and conservative care (group B, n=14). Pre- and postoperative images, and images taken shortly before and after the occurrence of fracture were evaluated for radiologic characteristics Results : Despite similar degrees of surgical correction of deformity, the fate of the two groups with proximal junctional compression fractures differed. Immediately after the fracture, the decrement of adjacent disc height in group A (32.3±7.6 mm to 23.7±8.4 mm, Δ=8.5±6.9 mm) was greater than group B (31.0±13.9 mm to 30.1±15.5 mm, Δ=0.9±2.9 mm, p=0.003). Pre-operative magnetic resonance imaging indicated that group A patients have a higher grade of disc degeneration adjacent to fractured vertebrae compared to group B (modified Pfirrmann grade, group A : 6.10±0.99, group B : 4.08±0.90, p=0.004). Binary logistic regression analysis indicated that decrement of disc height was the only associated risk factor for future revision surgery (odds ratio, 1.891; 95% confidence interval, 1.121-3.190; p=0.017). Conclusion : Proximal junctional vertebral compression fractures with greater early-stage decrement of adjacent disc height were associated with increased risk of future neurological deterioration and necessity of revision. The condition of adjacent disc degeneration should be considered regarding severity and revision rate of proximal junctional kyphosis/proximal junction failures.

• Journal of Korean Neurosurgical Society
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• 제46권4호
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• pp.292-299
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• 2009

Objective : Clinical and radiological results of posterior dynamic stabilization using interspinous U (ISU, $Coflex^{TM}$, Paradigm Spine $Inc.^{(R)}$, NY, USA) were analyzed in comparison with posterior lumbar interbody fusion (PLIF) in degenerative lumbar spinal stenosis (LSS). Methods : A retrospective study was conducted for a consecutive series of 61 patients with degenerative LSS between May 2003 and December 2005. We included only the patients completed minimum 24 months follow up evaluation. Among them, 30 patients were treated with implantation of ISU after decompressive laminectomy (Group ISU) and 31 patients were treated with wide decompressive laminectomy and posterior lumbar interbody fusion (PLIF; Group PLIF). We evaluated visual analogue scale (VAS) and Oswestry Disability Index (ODI) for clinical outcomes (VAS, ODI), disc height ratio disc height (DH), disc height/vertebral body length ${\times}100$), static vertebral slip (VS) and depth of maximal radiolucent gap between ISU and spinous process) in preoperative, immediate postoperative and last follow up. Results : The mean age of group ISU ($66.2{\pm}6.7$ years) was 6.2 years older than the mean age of group PLIF ($60.4{\pm}8.1$ years; p=0.003). In both groups, clinical measures improved significantly than preoperative values (p<0.001). Operation time and blood loss was significantly shorter and lower in group ISU than group PLIF (p<0.001). In group ISU, the DH increased transiently in immediate postoperative period ($15.7{\pm}4.5%{\rightarrow}18.6{\pm}5.9%$), however decreased significantly in last follow up ($13.8{\pm}6.6%$, p=0.027). Vertebral slip (VS) of spondylolisthesis in group ISU increased during postoperative follow-up ($2.3{\pm}3.3{\rightarrow}8.7{\pm}6.2$, p=0.040). Meanwhile, the postoperatively improved DH and VS was maintained in group PLIF in last follow up. Conclusion : According to our result, implantation of ISU after decompressive laminectomy in degenerative LSS is less invasive and provides similar clinical outcome in comparison with the instrumented fusion. However, the device has only transient effect on the postoperative restoration of disc height and reduction of slip in spondylolisthesis. Therefore, in the biomechanical standpoint, it is hard to expect that use of Interspinous U in decompressive laminectomy for degenerative LSS had long term beneficial effect.

• Journal of Korean Neurosurgical Society
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• 제62권1호
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• pp.53-60
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• 2019

Objective : The purpose of this study was to determine the efficacy of intra-operative cell salvage system (ICS) to decrease the need for allogeneic transfusions in patients undergoing major spinal deformity surgeries. Methods : A total of 113 consecutive patients undergoing long level posterior spinal segmental instrumented fusion (${\geq}5$ levels) for spinal deformity correction were enrolled. Data including the osteotomy status, the number of fused segments, estimated blood loss, intra-operative transfusion amount by ICS (Cell $Saver^{(R)}$, $Haemonetics^{(C)}$, Baltimore, MA, USA) or allogeneic blood, postoperative transfusion amount, and operative time were collected and analyzed. Results : The number of patients was 81 in ICS group and 32 in non-ICS group. There were no significant differences in demographic data and comorbidities between the groups. Autotransfusion by ICS system was performed in 53 patients out of 81 in the ICS group (65.4%) and the amount of transfused blood by ICS was 226.7 mL in ICS group. The mean intra-operative allogeneic blood transfusion requirement was significantly lower in the ICS group than non-ICS group (2.0 vs. 2.9 units, p=0.033). The regression coefficient of ICS use was -1.036. Conclusion : ICS use could decrease the need for intra-operative allogeneic blood transfusion. Specifically, the use of ICS may reduce about one unit amount of allogeneic transfusion in major spinal deformity surgery.