Runx3 Restoration Regresses K-Ras-Activated Mouse Lung Cancers and Inhibits Recurrence.

Oncogenic K-RAS mutations occur in approximately 25% of human lung cancers and are most frequently found in codon 12 (G12C, G12V, and G12D). Mutated K-RAS inhibitors have shown beneficial results in many patients; however, the inhibitors specifically target K-RASG12C and acquired resistance is a common occurrence. Therefore, new treatments targeting all kinds of oncogenic K-RAS mutations with a durable response are needed. RUNX3 acts as a pioneer factor of the restriction (R)-point, which is critical for the life and death of cells. RUNX3 is inactivated in most K-RAS-activated mouse and human lung cancers. Deletion of mouse lung Runx3 induces adenomas (ADs) and facilitates the development of K-Ras-activated adenocarcinomas (ADCs). In this study, conditional restoration of Runx3 in an established K-Ras-activated mouse lung cancer model regressed both ADs and ADCs and suppressed cancer recurrence, markedly increasing mouse survival. Runx3 restoration suppressed K-Ras-activated lung cancer mainly through Arf-p53 pathway-mediated apoptosis and partly through p53-independent inhibition of proliferation. This study provides in vivo evidence supporting RUNX3 as a therapeutic tool for the treatment of K-RAS-activated lung cancers with a durable response.

The TGFß→TAK1→LATS→YAP1 Pathway Regulates the Spatiotemporal Dynamics of YAP1.

The Hippo kinase cascade functions as a central hub that relays input from the "outside world" of the cell and translates it into specific cellular responses by regulating the activity of Yes-associated protein 1 (YAP1). How Hippo translates input from the extracellular signals into specific intracellular responses remains unclear. Here, we show that transforming growth factor ß (TGFß)-activated TAK1 activates LATS1/2, which then phosphorylates YAP1. Phosphorylated YAP1 (p-YAP1) associates with RUNX3, but not with TEAD4, to form a TGFß-stimulated restriction (R)-point-associated complex which activates target chromatin loci in the nucleus. Soon after, p-YAP1 is exported to the cytoplasm. Attenuation of TGFß signaling results in re-localization of unphosphorylated YAP1 to the nucleus, where it forms a YAP1/TEAD4/SMAD3/AP1/p300 complex. The TGFß-stimulated spatiotemporal dynamics of YAP1 are abrogated in many cancer cells. These results identify a new pathway that integrates TGFß signals and the Hippo pathway (TGFß→TAK1→LATS1/2→YAP1 cascade) with a novel dynamic nuclear role for p-YAP1.

Anti-tumor effects of rivoceranib against canine melanoma and mammary gland tumour in vitro and in vivo mouse xenograft models.

BACKGROUND: Rivoceranib, a novel tyrosine kinase inhibitor, exhibits anti-tumour effects by selectively blocking vascular endothelial growth factor receptor-2 (VEGFR2) in cancer cells. Recently, the therapeutic effects of rivoceranib on solid tumours have been elucidated in human patients. However, the anti-tumour effects of rivoceranib against canine cancer remain unclear. Here, we investigated the anti-tumour effects of rivoceranib using in vitro and in vivo mouse xenograft models. METHODS: We performed cell proliferation, cell cycle, and migration assays to determine the effects of rivoceranib on canine solid tumour cell lines in vitro. Furthermore, apoptosis and angiogenesis in tumour tissues were examined using a TUNEL assay and immunohistochemistry methods with an anti-cluster of differentiation-31 antibody, respectively. Additionally, the expression levels of cyclin-D1 and VEGFR2 activity were determined using western blot analysis. RESULTS: Rivoceranib treatment showed anti-proliferative effects and mediated cell cycle arrest in the canine melanoma cell line (LMeC) and the mammary gland tumour (MGT) cell line (CHMp). In animal experiments, rivoceranib decreased the average volume of LMeC cells compared to that following control treatment, and similar results were observed in CHMp cells. Histologically, rivoceranib induced apoptosis and exerted an anti-angiogenic effect in tumour tissues. It also downregulated the expression of cyclin-D1 and inhibited VEGFR2 activity. CONCLUSION: Our results show that rivoceranib inhibits proliferation and migration of tumour cells. These findings support the potential application of rivoceranib as a novel chemotherapeutic strategy for canine melanoma and MGTs.

Comparison of Fusion Rate between Demineralized Bone Matrix versus Autograft in Lumbar Fusion : Meta-Analysis.

The demineralized bone matrix (DBM) as the bone graft material to increase the fusion rate was widely used in spinal fusion. The current study aimed to compare the fusion rate of DBM to the fusion rate of autograft in lumbar spine fusion via meta-analysis of published literature. After systematic search, comparative studies were selected according to eligibility criteria. Checklist (risk of bias assessment tool for non-randomized study) was used to evaluate the risk of bias of the included nonrandomized controlled studies. The corresponding 95% confidence interval (95% CI) were calculated. We also used subgroup analysis to analyze the fusion rate of posterolateral lumbar fusion and lumbar interbody fusion. Eight studies were finally included in this meta-analysis. These eight studies included 581 patients. Among them, 337 patients underwent spinal fusion surgery using DBM (DBM group) and 204 patients underwent spinal fusion surgery with mainly autologous bone and without using DBM (control group). There was no significant differences of fusion rate between the two groups in posterolateral fusion analysis (risk ratio [RR], 1.03; 95% CI, 0.90-1.17; p=0.66) and interbody fusion analysis (RR, 1.13; 95% CI, 0.91-1.39; p=0.27). Based on the available evidence, the use of DBM with autograft in posterolateral lumbar spine fusion and lumbar interbody fusion showed a slightly higher fusion rate than that of autograft alone; however, there was no statistically different between two groups.

Cervical Cerebrospinal Fluid Leakage Concomitant with a Thoracic Spinal Intradural Arachnoid Cyst.

We encountered a very rare case of spontaneous spinal cerebrospinal fluid (CSF) leakage and a spinal intradural arachnoid cyst (AC) that were diagnosed at different sites in the same patient. These two lesions were thought to have interfered with the disease onset and deterioration. A 30-year-old man presented with sudden neck pain and orthostatic headache. Diplopia, ophthalmic pain, and headache deteriorated. CSF leakage was confirmed in C2 by radioisotope cisternography, and an epidural blood patch was performed. While his symptoms improved gradually, paraparesis suddenly progressed. Thoracolumbar magnetic resonance imaging (MRI) revealed an upper thoracic spinal intradural AC, which was compressing the spinal cord. We removed the outer membrane of the AC and performed fenestration of the inner membrane after T3-4 laminectomy. Postoperative MRI showed complete removal of the AC and normalized lumbar subarachnoid space. All neurological deficits including motor weakness, sensory impairment, and voiding function improved to normal. We present a case of spontaneous spinal CSF leakage and consecutive intracranial hypotension in a patient with a spinal AC. Our report suggests that if spinal CSF leakage and a spinal AC are diagnosed in one patient, even if they are located at different sites, they may affect disease progression and aggravation.

Cushing Syndrome: A Potential Risk of Bilateral Postoperative Ischemic Optic Neuropathy after Lumbar Fusion.

This is a report of a 58-year-old female with Cushing syndrome who underwent posterior lumbar fusion and lost both her vision completely. She was diagnosed with posterior ischemic optic neuropathy. Cushingoid features such as buffalo hump and central obesity might have attributed in triggering posterior ischemic optic neuropathy. When laid prone for surgery, perioperative high abdominal pressure causes venous hypertension leading to increase amount of blood loss. To compensate, infusion of large quantities of intravenous fluids is necessary which leads to hemodilution which decreases ocular perfusion pressure. Hypercoagulability of Cushing syndrome is also potentially a risk factor of this condition which increases the incidence of venous thromboembolism. For there is no known effective treatment for posterior ischemic optic neuropathy, means to prevent this complication must be strategically reviewed. When performing long spine surgery on patient who has Cushing syndrome or cushingoid features, caution must be taken to avoid this devastating complication.

A functional regulatory variant of MYH3 influences muscle fiber-type composition and intramuscular fat content in pigs.

Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5'-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs.

Predictive formula of ideal lumbar lordosis and lower lumbar lordosis determined by individual pelvic incidence in asymptomatic elderly population.

PURPOSE: This study aimed to obtain reference values of lumbar lordosis (LL) and lower LL (LLL) from normal asymptomatic groups, determine the relationship between them and pelvic incidence (PI), and establish the predictive formula for ideal LLL in the elderly Korean population. METHODS: Standing plain lateral radiographs of the whole spine, including the pelvis, were analyzed in asymptomatic adult male volunteers without back pain or prior surgery involving the spine or lower extremity. Volunteers with scoliosis, spondylolisthesis, segmental disk space narrowing, and/or compression fractures in the radiographs were excluded. The following parameters were measured: LL, LLL, and pelvic parameters including PI. The values of PI-LL and PI-LLL were calculated, and the formula using stepwise multiple regression analysis was made. A P value of < 0.05 was considered statistically significant. RESULTS: The study participants included 150 volunteers. All were male participants with an average age of 64.1 ± 6.4. The average value of height, weight, and body mass index was 167.0 ± 5.5 cm, 67.3 ± 9.8 kg, and 24.1 ± 3.1 kg/m2, respectively. The average LL was - 57.5° ± 9.0°, LLL was - 41.7° ± 7.0°, and PI was 48.6° ± 8.6°. The formula was established as follows: PI-LL = 0.38 × PI - 27.61 (R2 = 0.172), PI-LLL = 0.77 × PI - 28.69 (R2 = 0.516), ideal LL = 0.62 × PI + 27.61 (R2 = 0.348), and ideal LLL = 0.225 × PI + 28.63 (R2 = 0.083). CONCLUSIONS: The ideal values of PI-LL and PI-LLL were inconsistent, and they have a positive correlation with PI in asymptomatic elderly population. Our data would be helpful as a normal reference value of ideal LL and LLL according to PI. These slides can be retrieved under Electronic Supplementary Material.

Effect of Vertebroplasty at the Upper Instrumented Vertebra and Upper Instrumented Vertebra +1 for Prevention of Proximal Junctional Failure in Adult Spinal Deformity Surgery: A Comparative Matched-Cohort Study.

BACKGROUND: This study aimed to compare radiographic outcomes of adult spinal deformity (ASD) surgery with or without 2-level prophylactic vertebroplasty (PVP) at the uppermost instrumented vertebra (UIV) and the vertebra 1 level proximal to the UIV. METHODS: This retrospective 1:2 matched-cohort comparative study enrolled 2 groups of patients undergoing ASD surgery, including 28 patients with PVP (PVP group) and 56 patients without PVP (non-PVP group), in 3 institutes between 2012 and 2015. The primary outcome measure was the incidence of proximal junctional kyphosis (PJK), proximal junctional failure (PJF), and proximal junctional fracture (PJFX). The secondary outcome measure were radiologic outcomes between PVP segments and non-PVP segments. RESULTS: Between the PVP group and non-PVP group, no significant differences were found in the incidence of PJK (13 [46.4%] vs. 26 [46.4%]; P = 1.000), PJF (11 [39.3%] vs. 18 [32.1%]; P = 0.516), and PJFX (11 [39.3%] vs. 18 [32.1%]; P = 0.516). The number of the PJFX segments was 16 and 33 in PVP segments and non-PVP segments, respectively. Until revision surgery or final follow-up, the PJFX had progressed in 24 non-PVP segments (82.7%), but not in PVP segments. The PJFX progression in all PVP segments stopped near the PVP mass at the final follow-up. Reoperation as a result of PJFX was performed in 1 patient (3.6%) and 8 patients (14.3%) in the PVP and non-PVP groups, respectively. CONCLUSIONS: PVP at UIV and vertebra 1 level proximal to the UIV cannot prevent PJK, PJF, and PJFX; however, it plays a positive role by delaying their progression. Furthermore, PVP tends to lower the reoperation rate after PJFX in ASD surgery.

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. METHODS: From 2007 to 2012, 30 consecutive patients with a minimum 5-yr follow-up having 3- or more level posterior cervical fusion met inclusion criteria. The following radiographic parameters were measured: C0-C2 lordosis, C2-C7 lordosis, C2-C7 SVA, T1 slope, and TS-CL. Pearson correlation coefficients were calculated between pairs of radiographic measures and health-related quality of life. RESULTS: Average follow-up period was 7.3 yr. C2-C7 SVA positively correlated with neck disability index (NDI) scores (r = 0.554). Regression models predicted a threshold C2-C7 SVA value of 40.8 mm and 70.6 mm correlated with moderate and severe disability based on the NDI score, respectively. The TS-CL had positive correlation with C2-C7 SVA and NDI scores (r = 0.841 and r = 0.625, respectively). Regression analyses revealed that a C2-C7 SVA value of 40 mm and 70 mm corresponded to a TS-CL value of 20° and 25°, respectively. CONCLUSION: Regression models predicted a threshold C2-C7 SVA (value of 40.8 mm and 70.6 mm) and TS-CL (value of 20° and 25°) correlated with moderate and severe disability based on the NDI, respectively. The cut-off value C2-C7 SVA and TS-CL modifier of the CSD classification can be revised accordingly.

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. The patients were divided into two groups according to a reference value based on the cut-off value of DAR. Demographic, surgical, radiological, and clinical outcomes were compared between the groups. RESULTS: There were no significant differences in the patient demographic and surgical data between the groups. The cut-off values for the total DAR (T-DAR) and the sagittal DAR (S-DAR) were 20.2 and 16.4, respectively (p=0.018 and 0.010). Both values were significantly associated with complications (p=0.016 and 0.005). In the higher T-DAR group, total complications (12 vs. 21, p=0.042) and late-onset complications (3 vs. 9, p=0.036) were significantly correlated with the T-DAR. The number of patients experiencing complications (9 vs. 11, p=0.029) and the total number of complications (13 vs. 20, p=0.015) were significantly correlated with the S-DAR. Worsening intraoperative neurophysiologic monitoring was more frequent in the higher T-DAR group (2 vs. 4) than in the higher S-DAR group (3 vs. 3). There was no difference in neurological deterioration between the groups after surgery. CONCLUSION: Both the T-DAR and the S-DAR are risk factors for complications after PVCR. Those who had a T-DAR >20.2 or S-DAR >16.4 experienced a higher rate of complications after PVCR.

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.METHODSForty consecutive patients who underwent multilevel PCOs for ASD at a single institution between 2012 and 2016 were included in this study. PCO was performed in 142 disc space levels in the lumbar spine. The authors defined the disc space level that obtained ≥ 10° AC in the sagittal plane by PCO as the AC group and the remaining patients as controls. The modified Pfirrmann grade, surgical level, implementation of the transforaminal lumbar interbody fusion (TLIF), and radiographic measurements were compared between the groups.RESULTSThere were 67 levels in the AC group and 75 in the control group. Multivariate analysis identified the surgical level at L4-5 (OR 3.802, 95% CI 1.127-12.827, p = 0.031), performing TLIF with PCO (OR 3.303, 95% CI 1.258-8.674, p = 0.015), and a preoperative kyphotic disc space angle (OR 1.397, 95% CI 1.231-1.585, p < 0.001) as the factors that significantly effected ≥ 10° AC in the sagittal plane after PCO.CONCLUSIONSIn ASD surgery, PCO cannot always achieve ≥ 10° AC in the sagittal plane. The factors that effected ≥ 10° AC in PCO for ASD were surgical level at L4-5, performing TLIF with PCO, and the preoperative kyphotic disc space angle.

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. According to the time period, the former and latter 17 patients were divided into group 1 and group 2, respectively. Patients' demographics, surgical, radiological/clinical outcomes, and complications were compared between the groups. The demographic data of the patients had no significant difference between the groups. The surgical time (492.5 ±â€Š164.8 vs 350.5 ±â€Š133.9 minutes, P = .010), estimated blood loss (1294.1 ±â€Š711.9 vs 974.1 ±â€Š905.9 mL, P = .045), and length of hospital stay (22.8 ±â€Š12.9 vs 13.4 ±â€Š3.9 days, P = .017) were significantly reduced in group 2. The correction of the PVCR site (40.5°â€Š±â€Š13.3° vs 41.2°â€Š±â€Š23.7°, P = .909), sagittal vertical axis (SVA, 81.9 ±â€Š7.2 mm vs 77.9 ±â€Š102.0 mm, P = .904) were not different between the groups. The total number of complications (22 vs 10, P = .031) and patients having complications (13 vs 7, P = .039) were lower in group 2. Additional surgery was significantly lower in group 2 (13 vs 3, P = .007). The clinical outcomes by revised Scoliosis Research Society-22 (SRS-22r) questionnaire were not different between the groups. Our series revealed that the complications after PVCR may reduce from 17 cases and surgical outcomes might be stabilized by 29 cases.

Instrumentation Failure after Partial Corpectomy with Instrumentation of a Metastatic Spine.

OBJECTIVE: To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis. METHODS: We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest. RESULTS: There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively). CONCLUSION: When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.

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. METHODS: Thirty-three patients underwent ACDF involving 3 or more levels for cervical stenosis, cervical degenerative disorder, or ossification of the posterior longitudinal ligament (February 2006-April 2015). Mean follow-up duration was 57.6 ± 33.2 months. Radiographic measurements included C0-2 lordosis, C2-7 lordosis, C2-7 sagittal vertical axis (SVA), T1 slope, and T1 slope minus cervical lordosis (TS-CL). Clinical outcomes were evaluated by Neck Disability Index (NDI) and visual analog scale (VAS) scores. RESULTS: There were significant correlations between C2-7 lordosis and T1 slope (r = 0.581, P = 0.004), and between C2-7 lordosis and TS-CL (r = -0.579, P = 0.004). C2-7 lordosis, C2-7 SVA, and TS-CL had no significant correlations with NDI or VAS score after surgery. C2-7 SVA was not significantly different before and after surgery. Postoperative TS-CL (P = 0.01) and changes in T1 slope (P = 0.028) and TS-CL (P = 0.01) were significantly correlated with changes in NDI. CONCLUSIONS: ACDF surgery involving 3 or more levels under neutral supine position did not significantly change the postoperative cervical alignment, and thus may not significantly affect cervical alignment or HRQOL.

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. According to the time period, the former and latter 23 patients were divided into group 1 and group 2, respectively. Patients' demographic data, curve magnitude, number of levels treated, amount of correction achieved, radiographic/clinical outcomes, and complications were compared between the groups. RESULTS: The majority were females (34 vs. 12) with average ages of 15.0 versus 15.6, respectively. The mean follow-up period was 24.6 months. The average number of fusion levels was similar with 10.3 and 11.5 vertebral bodies in groups 1 and 2, respectively. The average Cobb angle of major curvature was 59.8° and 58.5° in groups 1 and 2, respectively. There observed significant reductions of operative time (324.4 vs. 224.7 minutes, P = 0.007) and estimated blood loss (648.3 vs. 438.0 mL, P = 0.027) in group 2. The correction rate of the major structural curve was greater in group 2 (70.7% vs. 81.0%, P = 0.001). There was no case of neurologic deficit, infection, and revision for screw malposition. One patient of group 1 underwent fusion extension surgery for shoulder asymmetry. CONCLUSION: Radiographic and clinical outcomes of AIS patients treated by a neurosurgeon were acceptable. AIS surgery may be performed with an acceptable rate of complications after about 20 surgeries. With acquisition of surgical experiences, neurosurgeons could perform deformity surgery for AIS effectively and safely.

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. We also aimed to assess the corrective potential of multilevel PCOs compared with a single-level pedicle subtraction osteotomy (PSO). METHODS: Between 2012 and 2016, the medical records of 70 consecutive patients who underwent a multilevel PCO (35 patients) or a single-level PSO (35 patients) for ASD in a single institute were reviewed. Baseline data, radiographic measurements, and clinical outcomes using the Scoliosis Research Society-22 (SRS-22) questionnaire were compared between groups. RESULTS: The following variables were no different between the groups: age at surgery, sex, level fused, preoperative and postoperative radiologic parameters, and bone mineral density T score. However, operation time (380.0 vs. 483.6 minutes), estimated blood loss (1175.7 vs. 1362.6 mL), and the number of complications (8 vs. 20) were significantly reduced in the PCO group compared with the PSO group. A significant improvement in the SRS-22 score was seen in both groups after surgery, although no difference was observed between the groups postoperatively. CONCLUSIONS: Multilevel PCOs for the correction of rigid ASD were slightly superior to PSO, regarding clinical outcomes. Radiographic outcomes were similar between groups. Thus, multilevel PCOs may be a viable option for the treatment of rigid ASD with a mobile segment.

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. METHODS: We retrospectively reviewed data from patients who had undergone spinal fusion involving more than 3 levels at a single institution between 2004 and 2015. Patients were matched for age, diagnosis, 3-column osteotomy, levels fused, and T score. Fifty patients with Ti rods were identified and appropriately matched to 50 consecutive patients with CoCr rods. RESULTS: The distributions of age at surgery, sex, diagnosis, 3-column osteotomy, levels fused, number of patients with previous surgical procedures, and T score did not significantly differ between the 2 groups. However, there were significant differences in length of follow-up (CoCr, 25.0 vs. Ti, 28.5 months; P < 0.001), fusion rate (CoCr, 45 [90%] vs. Ti, 33 [66%]; P = 0.004), occurrence of rod breakage (CoCr, 0 vs. T, 8 [16%]; P = 0.006), and junctional kyphosis (CoCr, 24 [46%] vs. Ti, 9 [18%]; P = 0.003). CONCLUSIONS: Our findings indicate that the use of CoCr rods is effective in ensuring stability of the posterior spinal construct and accomplishment of spinal fusion. Furthermore, our results indicate that junctional kyphosis may occur more frequently in CoCr systems than in Ti systems.