Radiographic and Clinical Outcomes Following Pedicle Subtraction Osteotomy : Minimum 2-Year Follow-Up Data.

Objective: The purpose of this study was to report the results of pedicle subtraction osteotomy (PSO) for fixed sagittal imbalance with a minimum 2-year follow-up. Besides, authors evaluated the effect of adjunctive multi-level posterior column osteotomy (PCO) on achievement of additional lumbar lordosis (LL) during PSO.

Methods: A total of 31 consecutive patients undergoing PSO for fixed sagittal imbalance were enrolled and analyzed.

Trends in Incidence and Treatment of Herniated Lumbar Disc in Republic of Korea : A Nationwide Database Study.

Objective: This study aimed to determine the incidence and analyze trends of the herniated lumbar disc (HLD) based on a national database in the Republic of Korea (ROK) from January 2008 to December 2016.

Methods: This study was a retrospective analysis of data obtained from the national health-claim database provided by the National Health Insurance Service for 2008-2016 using the International Classification of Diseases. The crude incidence and age-standardized incidence of HLD were calculated, and additional analysis was conducted according to age and sex.

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

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.

Anatomic Trajectory Screw Fixation at Upper Instrumented Vertebra Is a Substantial Risk Factor for Proximal Junctional Kyphosis.

Background: This study aimed to investigate the risk of proximal junction kyphosis (PJK) and proximal junction failure (PJF) associated with screw trajectory (straightforward vs. mixed vs. anatomic) at upper instrumented vertebra (UIV).

Kyphectomy and interbody fixation using lag screws in a child with myelomeningocele kyphosis: a technical case report.

A 5-year-old boy had a thoracolumbar-level MMC that had been repaired at the day after birth and kyphotic deformity got worse as he grew. He complained of discomfort about not being able to take a supine posture and decided to perform surgery for kyphosis. In our case, surgical correction is offered to stop the deformity progression, manage the associated pain, and finally to gain sitting and supine posture.

Clinical Efficacy of Intra-Operative Cell Salvage System in Major Spinal Deformity Surgery.

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 (≥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®, Haemonetics©, Baltimore, MA, USA) or allogeneic blood, postoperative transfusion amount, and operative time were collected and analyzed.

Total Deformity Angular Ratio as a Risk Factor for Complications after Posterior Vertebral Column Resection Surgery.

Objective: The aim of the present study was to identify whether the deformity angular ratio (DAR) influences the occurrence of complications after posterior vertebral column resection (PVCR) and to establish the DAR cut-off value.

Methods: Thirty-six consecutive patients undergoing PVCR from December 2010 to October 2016 were reviewed. The relationships between the total, sagittal, and coronal DAR and complications were assessed using receiver operator characteristics curves.

Factors for the acquisition of 10° angular change at the lumbar spine through posterior column osteotomy in adult spinal deformity surgery.

OBJECTIVEPosterior column osteotomy (PCO) has been known to provide an angular change (AC) of approximately 10° in sagittal plane deformity. However, whether PCO can actually obtain an AC of ≥ 10° depending on the particular level in the lumbar spine and which factors can effect a gain of ≥ 10° AC after PCO remain to be elucidated. The aim of this study was to identify the factors that effect a gain of ≥ 10° AC through PCO by comparing radiographic measurements between an AC group and a control group before and after adult spinal deformity (ASD) surgery.

Failure to generate baseline muscle motor evoked potentials during spine surgery: Risk factors and association with the postoperative outcomes.

Objective: To identify factors associated with the failure to generate baseline muscle motor evoked potentials (mMEPs) during spinal surgery, and to determine the association between baseline mMEP generation and postoperative outcomes.

Methods: A total of 345 patients who underwent spine surgery with intraoperative mMEP monitoring were included, and we retrospectively reviewed their demographic/clinical parameters, and mMEP recording results according to lesion locations.

Results: Multivariable logistic regression analysis revealed that preoperative Medical Research Council grade of the weakest muscle <3 was significantly associated with failure of baseline mMEP generation in both cervical and thoracic lesions.

Surgical and radiological outcomes after posterior vertebral column resection according to the surgeon's experience.

The purpose of this study was to estimate and analyze the radiological, surgical, and clinical results of posterior vertebral column resection (PVCR) according to the surgeon's experience. Although PVCR has been recognized as the most powerful surgical technique to correct severe spinal deformity, PVCR is a technically demanding procedure with a high complication rate. A retrospective review of the chart and radiographic data of 34 consecutive patients who received PVCR was carried out.

Risk Factor Analysis of Change in Intraoperative Neurophysiologic Monitoring During Cervical Open Door Laminoplasty.

Objective: The aim of this study is to determine the risk factors affecting intraoperative neurophysiologic monitoring (IONM) changes, when such changes take place, and clinical outcomes associated with IONM change during cervical open door laminoplasty (COL) for cervical compressive myelopathy.

Methods: Between 2010 and 2015, 79 patients who underwent COL with IONM recording were studied. Changes in motor evoked potentials or somatosensory evoked potentials over an alarm criterion were defined as IONM change.

Assessment of T1 Slope Minus Cervical Lordosis and C2-7 Sagittal Vertical Axis Criteria of a Cervical Spine Deformity Classification System Using Long-Term Follow-up Data After Multilevel Posterior Cervical Fusion Surgery.

Backgound: Recently, previous research proposed a cervical spine deformity (CSD) classification using a modified Delphi approach. However, C2-C7 sagittal vertical axis (SVA) and T1 slope minus C2-C7 lordosis (TS-CL) cut-off values for moderate and severe disability were based on expert opinion.

Objective: To investigate the validity of a CSD classification system.

Clinical and Radiological Outcomes of Posterior Vertebral Column Resection for Severe Spinal Deformities.

Objective: The aim of this study was to investigate clinical and radiological outcomes of patients who underwent posterior vertebral column resection (PVCR) by a single neurosurgeon in a single institution.

Methods: Thirty-four consecutive patients with severe spinal deformities who underwent PVCR between 2010 and 2016 were enrolled. The radiographic measurements included a kyphotic angle of PVCR levels (VCR angle), sagittal vertical axis (SVA), thoracic kyphosis, lumbar lordosis (LL), and spinopelvic parameters.

Relationship Between Cervical Sagittal Alignment and Patient Outcomes After Anterior Cervical Fusion Surgery Involving 3 or More Levels.

Background: T1 slope minus C2-7 lordosis (TS-CL) and cervical sagittal alignment reportedly affect health-related quality of life (HRQOL) scores after multilevel posterior cervical fusion surgery. There are no reports of a relationship between cervical alignment and patient outcomes after anterior cervical discectomy and fusion (ACDF) involving 3 or more levels. This study aimed to investigate the relationship between cervical sagittal alignment and patient-reported HRQOL after ACDF involving 3 or more levels.

Freehand S2 Alar-Iliac Screw Placement Using K-Wire and Cannulated Screw : Technical Case Series.

Objective: Among the various sacropelvic fixation methods, S2 alar-iliac (S2AI) screw fixation has several advantages compared to conventional iliac wing screw. However, the placement of S2AI screw still remains a challenge. The purpose of this study was to describe a novel technique of free hand S2AI screw insertion using a K-wire and cannulated screw, and to evaluate the accuracy of the technique.

Proximal Junctional Kyphosis and Proximal Junctional Failure Following Adult Spinal Deformity Surgery.

The purpose of this review is the current understanding of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) following adult spinal deformity (ASD) surgery. We carried out a systematic search of PubMed for literatures published up to September 2017 with "proximal junctional kyphosis," "proximal junctional failure," and "adult spinal deformity" as search terms. A total of 98 literatures were searched.

Surgical Removal of a Ruptured Radiculomedullary Artery Aneurysm: A Case Report.

Subarachnoid hemorrhage due to a solitary spinal aneurysm is extremely rare, and diagnosis and treatment are challenging. We report a rare case of a ruptured radiculomedullary artery aneurysm in a patient with Behçet disease. A 49-year-old man presented with severe lower abdominal and leg pain.

Adolescent Idiopathic Scoliosis Surgery by a Neurosurgeon: Learning Curve for Neurosurgeons.

Objective: To determine a neurosurgeon's learning curve of surgical treatment for adolescent idiopathic scoliosis (AIS) patients.

Methods: This study is a retrospective analysis. Forty-six patients were treated by a single neurosurgeon between 2011 and 2017 using posterior segmental instrumentation and fusion.

Long-Term Results Following Surgical Resection of Chordomas in the Craniocervical Junction and the Upper Cervical Spine: Review of 12 Consecutive Cases.

Background: Since chordoma is refractory to chemotherapy and conventional radiotherapy, radical surgical resection is mandatory. However, it is surgically demanding in the craniocervical junction (CCJ) and upper cervical spine.

Objective: To analyze long-term surgical results of cervical chordomas.

Multilevel Posterior Column Osteotomies Are Not Inferior For the Correction of Rigid Adult Spinal Deformity Compared with Pedicle Subtraction Osteotomy.

Background: Posterior column osteotomy (PCO) has been used for the correction of various spinal deformities. However, little evidence is available regarding the effects of multilevel PCO in adult spinal deformity (ASD) surgery. This study aimed to show the usefulness of PCO in rigid ASD surgery by assessing radiographic and clinical outcomes.

Corticobulbar motor evoked potentials from tongue muscles used as a control in cervical spinal surgery.

Objective: Motor evoked potentials (MEPs) changes might be caused to the non-surgically induced factors during cervical spinal surgery. Therefore, control MEPs recorded cranially to the exit of the C5 root are highly recommendable in cervical spinal surgery. We studied whether corticobulbar MEPs (C-MEPs) from tongue muscle could be used as a control MEPs in cervical spinal surgery.

Clinical Impact of T1 Slope Minus Cervical Lordosis After Multilevel Posterior Cervical Fusion Surgery: A Minimum 2-Year Follow Up Data.

Study Design: Retrospective study.

Objective: To assess the long-term relationship between sagittal alignment of the cervical spine and patient-reported health-related quality-of-life (HRQOL) scores after multilevel posterior cervical fusion, and to explore whether an analog of T1 slope minus C2-C7 lordosis ('T1S-CL') impacts on patients' clinical outcomes.

Background: A 6-month follow-up study demonstrated that, similar to the thoracolumbar spine, the severity of disability increases with sagittal malalignment after cervical reconstruction surgery.

Comparative Study Between Cobalt Chrome and Titanium Alloy Rods for Multilevel Spinal Fusion: Proximal Junctional Kyphosis More Frequently Occurred in Patients Having Cobalt Chrome Rods.

Background: The use of titanium alloy (Ti) rods is frequently associated with rod fracture after spinal fixation. To address this issue, cobalt chrome (CoCr) rods, which are advantageous because of their greater strength and resistance to fatigue relative to Ti rods, have been introduced. The purpose of the present study was to compare radiographic outcomes after the use of Ti versus CoCr rods in a matched cohort of patients undergoing posterior spinal fusion for treatment of spinal instability.

Radiographic and Clinical Results of Freehand S2 Alar-Iliac Screw Placement for Spinopelvic Fixation: An Analysis of 45 Consecutive Screws.

Study Design: This was a retrospective clinical case series.

Objective: The purpose of this study was to evaluate mid-term outcomes of S2 ala-iliac (S2AI) screw fixation in patients who underwent multilevel posterior spinal fusion surgery.

Summary Of Background Data: There have been few reports on radiographic and clinical outcomes in patients who underwent spinopelvic reconstruction surgery using S2AI screw installation.

Multi-channel motor evoked potential monitoring during anterior cervical discectomy and fusion.

Objectives: Anterior cervical discectomy and fusion (ACDF) surgery is the most common surgical procedure for the cervical spine with low complication rate. Despite the potential prognostic benefit, intraoperative neurophysiological monitoring (IONM), a method for detecting impending neurological compromise, is not routinely used in ACDF surgery. The present study aimed to identify the potential benefits of monitoring multi-channel motor evoked potentials (MEPs) during ACDF surgery.