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Background. The nano-hydroxyapatite/polyamide-66 (n-HA/PA66) cage is a biomimetic cage with a lower elastic modulus than the titanium mesh cage (TMC). This study aimed to compare the long-term outcomes of the n-HA/PA66 cage and TMC in the anterior reconstruction of thoracic and lumbar fractures. Methods. We retrospectively studied 113 patients with acute traumatic thoracic or lumbar burst fractures, comprising 60 patients treated with the TMC and 53 treated with the n-HA/PA66 cage for anterior reconstruction following single-level corpectomy. The radiographic data (cage subsidence, fusion status, segmental sagittal alignment) and clinical data (visual analogue scale (VAS) for pain and Oswestry Disability Index (ODI) for function) were evaluated preoperatively, postoperatively, and at final follow-up after a minimum 7-year period. Results. The n-HA/PA66 and TMC groups had similar final fusion rates (96.2% vs. 95.0%). The cage subsidence at final follow-up was 2.3 ± 1.6 mm with subsidence of more than 3 mm occurring in 24.5% in the n-HA/PA66 group, which was significantly lower than the respective values of 3.9 ± 2.5 mm and 58.3% in the TMC group. The n-HA/PA66 group also had better correction of the bisegmental kyphotic angle than the TMC group (7.1°±7.5°vs 1.9°±8.6°, p

Hypoxia-inducible factor (HIF) plays a crucial role in regulating the hypoxia-inducible state of nucleus pulposus cells in the intervertebral disc. In addition, the oxygen-dependent conversion of HIF-1α in nucleus pulposus cells is controlled by the protein proline 4-hydroxylase domain (PHD) family. To explore whether HIF-1α can be regulated by modulating PHD homologs to inhibit nucleus pulposus degeneration, PHD2-shRNAs were designed and a PHD2 interference vector was constructed. The expression of HIF-1α and PHD2 genes in the nucleus pulposus cells in the experimental group was detected by RT-PCR, and the expression of HIF-1α, MMP-2, Aggrecan, and Col II proteins in the P0-P3 cells in the experimental group and the control group was detected by Western blotting. The apoptosis of P0-P3 nucleus pulposus cells was detected by flow cytometry. After lentivirus infection, the interference efficiency of the PHD2 gene decreased with cell passage. The apoptosis of P1-P3 cells in the experimental group was significantly lower than that in the control group or degeneration group. Compared to the control group, the expression of HIF-1α, Aggrecan, and Col II proteins increased significantly, and the expression of MMP-2 protein decreased significantly. In conclusion, interference with PHD2 can upregulate the expression of HIF-1α, accelerate anabolism, reduce catabolism, inhibit apoptosis of nucleus pulposus cells, and then these can inhibit degeneration of nucleus pulposus cells. Our results can provide an effective therapeutic target in intervertebral discs during intervertebral disc degeneration, and this may have important clinical significance.

BackgroundThe distal adding-on phenomenon has attracted extensive discussion in the field of spine surgery due to the continual occurrence after scoliosis correction. Previous work has mainly focused on adolescent idiopathic scoliosis (AIS), and a relatively high number of theories for the mechanism of the distal adding-on phenomenon has been proposed for these kinds of patients. Severe and rigid scoliosis, as a special disease form, has a unique etiology, clinical manifestations and internal mechanisms distinct from those of AIS. Given the uniqueness of this disease, the mechanism and causes of the distal adding-on phenomenon have been infrequently studied in depth.ObjectiveTo define clinical and radiological factors associated with distal adding-on in patients with severe and rigid scoliosis.MethodsRadiographic parameters and demographic data of patients with severe and rigid scoliosis were evaluated preoperatively, after posterior instrumentation and fusion surgery, and at the final follow-up via radiographs. According to the appearance of distal adding-on at the final follow-up, the patients were grouped into the Adding-on and the Non-adding-on groups. Various radiological parameters were analyzed in stepwise multivariate logistic regression to identify the variables associated with distal adding-on, which were then incorporated into a nomogram. The predictive performance and calibration of the nomograms for distal adding-on were assessed using C statistics and calibration plots.Results93 patients (21 in the Adding-on and 72 in the Non-adding-on group) were included. The incidence of distal adding-on was 22.6%. The variables associated with distal adding-on were the anterior release, posterior internal distraction, and later posterior spinal fusion (IP) procedure, the posterior vertebral column resection and posterior spinal fusion (PVCR) procedure, postoperative apical vertebral translation (Post-AVT) and preoperative slope of the line linking the pedicles on the concave side of the upper- and lower-end vertebrae (Tan α). Combining these factors, the nomogram achieved a concordance index of 0.92 in predicting distal adding-on and had well-fitted calibration curves.ConclusionsFor patient with a negative Tanα in severe and rigid scoliosis, the risk of distal adding-on tended to increase, and it is recommended to give priority to IP or PVCR. In the final correction, a smaller Post-AVT should not be pursued excessively.

Background Proximal junctional kyphosis is a common complication after posterior fusion in patients with adolescent idiopathic scoliosis and is correlated with postoperative changes of thoracic kyphosis. In lenke 5c patients, higher postoperative LL and spontaneous change of TK may produce an effect on final PJK. However, no studies has been performed to evaluate the correlation of PJK with thoracocervical parameters in patients with AIS. Methods Data from 98 patients who underwent posterior fusion for Lenke 5C AIS with 2 years of follow-up were retrospectively reviewed. Patients in the extended fusion group underwent fusion at levels higher than upper-end vertebra + 2 (n = 38), and those in the thoracolumbar/lumbar (TL/L) fusion group underwent fusion at UEV + 2 or lower (n = 60). Results During an average follow-up of 38.1 months, 23 of 98 patients developed PJK. The extended fusion group had a higher incidence of PJK than the TL/L fusion group (14/38 vs. 9/60, respectively; P = 0.01) and a significantly greater decrease in thoracic kyphosis than the TL/L group (P P Conclusions The preoperative TIA could be a predictor of PJK. Among patients with Lenke 5C AIS, those with a TIA of > 71° are more likely to develop PJK. Additionally, extended fusion in patients with Lenke 5C may increase the risk of PJK.

Background This study assesses performance and utility of motor evoked potentials and somatosensory evoked potentials during corrective surgery to thoracic tuberculosis with kyphosis (TTK), as well as corresponding risk factors. Methods Patients diagnosed with TTK and underwent TTK corrective surgery from 2012 to 2018 were included. Relevant Data were retrospectively collected. Measures of intraoperative neurophysiological monitoring (IONM) performance were calculated. A receiver operating characteristic (ROC) curve and area under ROC curve (AUC) were deployed to identify the diagnostic accuracy of potential recovery. Univariate and multivariate analysis were performed to determine risk factors correlated with IONM alerting. Results 68 patients were included. The mean age was 31.7±20.3 years (3-78 years). IONM alerting occurred in 12 surgeries (12/68, 17.6%), of which 6 were somatosensory evoked potential (SSEP) alerting, 2 motor evoked potential (MEP) alerting, and 4 combinations of both SSEP and MEP. There were 10 posterior vertebral column resections (PVCRs) and 2 pedicle subtraction osteotomies (PSOs) with 1.83±1.19 vertebra resected. Four (4/68, 5.89%) patients were identified with presence of postoperative neurological deficits (PNDs). Calculated measures of performance of MEP and SSEP were as follows: sensitivity of 0.75, specificity of 0.86, positive predictive value (PPV) of 0.25, and negative predictive value (NPV) of 0.98 respectively. The AUC of evoked potential recovery in diagnosing a PND was 0.884. On logistic regression analysis, sever kyphosis was determined as the independent risk factor for IONM alerting. Conclusions Multimodal IONM can benefit 66.7% participants from neural impingement under appropriate intervention after IONM alerting. Corrective surgery in TTK is at risk of spinal injury, especially in severe kyphosis requiring three-column osteotomy.

Objective The nano-hydroxyapatite/polyamide66 (n-HA/PA66) cage is a novel biomimetic nonmetal cage, whereas the polyetheretherketone (PEEK) cage has been widely used for decades with excellent clinical outcomes. However, there has been no long-term comparison of these 2 cages in anterior cervical reconstruction. Methods This retrospective study included 98 patients who underwent single-level anterior cervical decompression and fusion (ACDF) from January 2009 to June 2011 with at least 7 years of follow-up; the PEEK cage was used in 51 patients (PEEK group), whereas the n-HA/PA66 cage was used in 47 (n-HA/PA66 group). The groups were compared regarding radiographic (cage subsidence, fusion status, cervical lordosis, and segmental sagittal alignment) and clinical (10-point visual analog scale and Japanese Orthopedic Association scores) parameters preoperatively, postoperatively, and at the final follow-up. Results The n-HA/PA66 and PEEK cages had similar fusion rates at the final follow-up (97.9% vs. 98.0%). The respective cage subsidence rates in the PEEK and n-HA/PA66 cage groups were 9.8% and 10.6%. There were no significant differences between the 2 groups in mean cervical lordosis, mean interbody height, segmental sagittal alignment, cervical lordosis, and 10-point visual analog scale and Japanese Orthopedic Association scores at the final follow-up. The n-HA/PA66 cages resulted in high fusion and low subsidence rates during long-term follow-up. Conclusions After single-level ACDF, the n-HA/PA66 cage showed similar radiographic fusion, subsidence rate, and clinical results compared with the PEEK cage during 7 years of follow-up. These results suggest that the n-HA/PA66 cage could be comparable with the PEEK cage for ACDF.

POEMS syndrome is a rare clonal plasma cell disease characterized by polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes. We report a rare case of neurological impairment in patients with concurrent cervical disc herniation and POEMS syndrome. A patient presented to a local hospital with C3/4 and C4/5 disc herniation, apparent spinal cord compression concomitant with neurological signs, and concurrent POEMS syndrome. Anterior cervical discectomy and fusion was performed. The limb numbness was only slightly alleviated, and 10 days postoperatively the patient complained of muscle weakness of the extremities and was referred to our hospital. The patients exhibited non-typical neurological signs and an enlarged liver and spleen that could not be explained. Electroneuromyography and immunofixation electrophoresis produced abnormal results. We diagnosed concurrent POEMS syndrome, for which drug therapy was prescribed. The patient’s symptoms receded. Patients presenting with cervical spondylopathy and non-typical neurological signs and symptoms or other systemic problems should be evaluated for the presence of concurrent disease and ruled out differential diagnoses.

Study Design Comparative study Objective To compare manual and deep learning-based automated measurement of Cobb angle in adolescent idiopathic scoliosis. Methods We proposed a fully automated framework to measure the Cobb angle of AIS patients. Whole-spine images of 500 AIS individuals were collected. 200 digital radiographic (DR) images were labeled manually as training set, and the remaining 300 images were used to validate by mean absolute error (MAE), Pearson or spearman correlation coefficients, and intra/interclass correlation coefficients (ICCs). The relationship between accuracy of vertebral boundary identification and the subjective image quality score was evaluated. Results The PT, MT, and TL/L Cobb angles were measured by the automated framework within 300 milliseconds. Remarkable 2.92° MAE, .967 ICC, and high correlation coefficient (r = .972) were obtained for the major curve. The MAEs of PT, MT, and TL/L were 3.04°, 2.72°, and 2.53°, respectively. The ICCs of these 3 curves were .936, .977, and .964, respectively. 88.7% (266/300) of cases had a difference range of ±5°, with 84.3% (253/300) for PT, 89.7% (269/300) for MT, and 93.0% (279/300) for TL/L. The decreased bone/soft tissue contrast (2.94 vs 3.26; P=.039) and bone sharpness (2.97 vs 3.35; P=.029) were identified in the images with MAE exceeding 5°. Conclusion The fully automated framework not only identifies the vertebral boundaries, vertebral sequences, the upper/lower end vertebras and apical vertebra, but also calculates the Cobb angle of PT, MT, and TL/L curves sequentially. The framework would shed new light on the assessment of AIS curvature.

Purpose We previously reported anterior release, posterior internal distraction, and subsequent spinal fusion (ARPIDF) for the correction of severe scoliosis with a satisfactory correction rate. However, surgical procedures were completed in 2–3 stages. Here we compare Cobb angle of ≥90° in scoliosis correction between a novel posterior multiple screws distraction reducer (MSDR) system and ARPIDF. Methods Thirty-six patients with severe scoliosis treated by MSDR or ARPIDF (n = 18 in both groups). We retrospectively analyzed and compared outcome measures between the two groups over a minimum follow-up duration of 2 years. The following variables were compared between the two groups: age at surgery, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, operation time, estimated blood loss, hospitalization time, follow-up duration, various radiological parameters, complication rate, and Scoliosis Research Society-30 score. Results There were no significant between-group differences with respect to age, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, and follow-up duration. Further, there was no significant difference in terms of preoperative, postoperative, and final follow-up findings of the radiographic data. However, the ARPIDF group had longer operation and hospitalization times and greater blood loss. In the ARPIDF group, 4 patient developed complications (infection, intraoperative neuromonitoring changes, transient dyspnea); none of these events occurred in the MSDR group. Conclusion The use of MSDR helped achieve greater scoliosis correction with a shorter operation time, lower blood loss, and lower complication rate than the use of ARPIDF. MSDR facilitates safer and easier correction of severe scoliosis without increasing surgical risk.

Background PIA has been proven to be a predictor for postoperative dysphagia in patients who undergo occipitospinal fusion. However, its predictive effect for postoperative dysphagia in patients who undergo OCF is unknown. The aim of this study was to evaluate the predictive ability of the pharyngeal inlet angle (PIA) for the occurrence of postoperative dysphagia in patients who undergo occipitocervical fusion (OCF). Methods Between 2010 and 2018, 98 patients who had undergone OCF were enrolled and reviewed. Patients were divided into two groups according to the presence of postoperative dysphagia. Radiographic parameters, including the atlas-dens interval (ADI), O-C2 angle (O-C2a), occipital and external acoustic meatus to axis angle (O-EAa), C2 tilting angle (C2Ta), C2-7 angle (C2-7a), PIA and narrowest oropharyngeal airway space (nPAS), were measured and compared. Simple linear regression and multiple regression analysis were used to evaluate the radiographic predictors for dysphagia. In addition, we used PIA = 90° as a threshold to analyze its effect on predicting dysphagia. Results Of the 98 patients, 26 exhibited postoperative dysphagia. Preoperatively, PIA in the dysphagia group was significantly higher than that in the nondysphagia group. We detected that O-C2a, O-EAa, PIA and nPAS all decreased sharply in the dysphagia group but increased slightly in the nondysphagia group. The changes were all significant. Through regression analyses, we found that PIA had a similar predictive effect as O-EAa for postoperative dysphagia and changes in nPAS. Additionally, patients with an increasing PIA exhibited no dysphagia, and the sensitivity of PIA Conclusions PIA could be used as a predictor for postoperative dysphagia in patients undergoing OCF. Adjusting a PIA level higher than the preoperative PIA level could avoid dysphagia. For those who inevitably had decreasing PIA, preserving intraoperative PIA over 90° would help avert postoperative dysphagia. Trial registration This trial has been registered in the Medical Ethics Committee of West China Hospital, Sichuan University. The registration number is 762 and the date of registration is Sep. 9 th, 2019.

Background Previous studies have reported the progression of deformity in patients with adolescent idiopathic scoliosis after implant removal. However, for patients with congenital scoliosis, few studies have investigated the prognosis after implant removal. Methods We observed 24 patients with congenital scoliosis, who underwent implant removal, for at least 3 years. Radiographic parameters and demographic data were compared to evaluate whether implant removal would lead to deformity progression. Results Four of the 24 patients (16.7%) suffered correction loss and underwent revision surgery (RS). All correction losses occurred within 12 months of implant removal. The average curve of fixed segments (9.84° ± 7.22° to 16.42° ± 16.79°; P = 0.017) and kyphosis of fixed segments (10.46° ± 13.42° to 18.98° ± 25.99°; P = 0.03) increased significantly throughout the follow-up. After excluding patients who underwent RS, the changes in curve of fixed segments (9.10°–11.58°) and kyphosis of fixed segments (8.50°–9.24°) were all within the measurement error. The coronal and sagittal balance maintained during the follow-up. Through comparison, we thought that the younger age and lower Risser’s grade with larger scoliosis might be risk factors for correction loss. Conclusions Implant removal after fusion surgery for congenital scoliosis may present loss of correction and require RS, thus preserving implants is recommended. When removal of instrumentation is inevitable, parents and patients should be counseled for potential loss of correction and RS, and patients should be monitored for the progression of deformity.

Background: Curcumin is the major component of turmeric, which has an anticancer property in multiple cancers, including hepatocellular carcinoma (HCC). However, the mechanisms are still largely unclear. This research aims to assess the pharmacological function of curcumin and explore the potential microRNA (miRNA)-mRNA regulatory mechanism in curcumin-mediated HCC progression. Materials and Methods: Hep3B and Huh-7 cells were used for in vitro experiments. Cells were exposed to various doses of curcumin, and transfection was conducted using Lipofectamine 2000. Cell proliferation, migration, and invasion were examined using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide or transwell assay. The abundances of miR-21-5p and gender-determining region Y-related high-mobility group box 6 (SOX6) were examined using quantitative real-time polymerase chain reaction or Western blot. The relationship between miR-21-5p and SOX6 was analyzed through luciferase reporter analysis. Results: Curcumin repressed HCC cell proliferation, migration, and invasion. miR-21-5p level was decreased in curcumin-treated cells, and miR-21-5p overexpression reversed curcumin-mediated inhibition of HCC progression. SOX6 was targeted through miR-21-5p, and SOX6 restoration attenuated miR-21-5p-induced promotion of HCC progression. Moreover, curcumin exposure increased SOX6 expression through regulating miR-21-5p, and knockdown of SOX6 overturned curcumin-modulated suppression of HCC progression. Conclusions: Curcumin repressed proliferation, migration, and invasion of HCC cells by regulating miR-21-5p and SOX6, indicating the promisingly pharmacological effect of curcumin in HCC.

The treatment of congenital hemivertebrae in the upper thoracic region is challenging. The objective of this study was to investigate the outcomes of posterior hemivertebral resection for the upper thoracic region. Twenty-one patients diagnosed with upper thoracic congenital scoliosis were included. All of them received hemivertebral resection surgery via the posterior-only approach with at least 2 years of follow-up. The radiographic parameters and Scoliosis Research Society-22 score were analyzed. All the intraoperative and postoperative complications were recorded retrospectively. The segmental main curve was 35.9° before surgery and 7.0° at the last follow-up, with an average correction rate of 80.2%. The total main curve was 44.1° before surgery and 11.6° at the last follow-up, with an average correction rate of 73.9%. The caudal compensatory curve was corrected from 20.2° to 7.1°, with an average correction rate of 64.9%. The segmental kyphosis was corrected from 30.9° to 8.9°, with an average correction rate of 65.5%. The total Scoliosis Research Society-22 score significantly improved in all patients at the last follow-up, mainly resulting from the improvement of the self-image, mental health, and satisfaction domains. The following complications were found: one pedicle fracture, two malpositioned screws, one transient neurologic deficit, one implant failure, and four postoperative curve progressions. Although good radiographic deformity correction and clinical results were achieved after surgery, the incidence rate of complications was high at 42.9%; great care should be taken to prevent them, especially for postoperative curve progression (19.0%).

Background Spinal tuberculosis accounts for more than 50% of bone tuberculosis cases. This study compared clinical, radiological and functional outcomes between anterior and posterior approaches for treatment of middle or lower thoracic spinal tuberculosis in elderly patients. Methods We retrospectively examined middle or lower thoracic spinal tuberculosis (T5–T12) in patients over 65 years. All procedures included debridement, decompression, autologous bone graft and fixation. Surgical procedure, surgical duration, estimated blood loss during surgery and laboratory results were recorded. Pleural effusion volume, thoracic cavity volume, Oswestry Disability Index score, neurological status, radiological parameters and complication rate were evaluated. Results No significant difference was found in surgical duration, blood loss, kyphosis angle correction, loss of correction, thoracic cavity volume, or complication rate between the two groups (P > 0.05). Average postoperative pleural effusion volumes were 605.9 ± 209.5 mL (377–1074 mL) and 262.9 ± 228.1 mL (0–702.4 mL) in the anterior and posterior groups, respectively (P = 0.004). Average hospitalization durations were 26.4 ± 10.5 days (17–53 days) and 19.2 ± 5.0 days (14–30 days) (P = 0.04). Average postoperative serum albumin levels were 24.19 ± 3.84 g/L (19–29.5 g/L) and 28.24 ± 2.52 g/L (24.4–31.6 g/L) (P = 0.01). No relapse or reinfection was observed in either group at the final follow-up. Surgical revision was not required in either group. Conclusions Both anterior and posterior surgeries can be used to treat middle or lower thoracic spinal (T5-T12) tuberculosis in elderly patients. In general, the posterior approach might be superior, especially for patients with poor general health.

Background and aims Population-based studies suggest a strong association between the presence of nonalcoholic fatty liver disease (NAFLD) and an increased risk of urolithiasis. However, the available information on the association of the severity of NAFLD with urolithiasis is limited. We hypothesised a link between the severity of NAFLD and the risk of urolithiasis. Methods We recruited 1527 adult patients with NAFLD who completed a comprehensive health checkup. The severity of NAFLD was measured with AST to platelet ratio (APRI score). Logistic regression analysis was used to detect the association of APRI score with the risk of urolithiasis among NAFLD patients. ROC analysis was used to assess the diagnostic value of APRI score for identifying urolithiasis among NAFLD patients. Results Multivariate analysis showed three independent risk factors for urolithiasis: obesity (OR 2.06 95%CI 1.35-3.13), APRI score (OR 1.29 95%CI 1.05-1.59), and serum uric acid (OR 1.07 95%CI 1.05-1.09), suggesting an independent association between the noninvasive staging of liver fibrosis and the risk of urolithiasis in NAFLD patients. A three-variable model (obesity, APRI score, and serum uric acid) with an AUROC of 0.73 (95% CI 0.70-0.75) was significant in identifying urolithiasis. Conclusions The severity of NAFLD is associated with the risk of urolithiasis among NAFLD patients. Moreover, a three-variable model (obesity, APRI score, serum uric acid) could serve as a useful tool for identifying individuals at high risk for urolithiasis in these patients.

Background Context Many different correction methods have been reported to treat severe and rigid scoliosis. In the past, anterior and posterior spinal fusion (APSF), which included an anterior release followed by posterior instrumented fusion, was widely applied. In recent years, anterior/posterior vertebral column resection (APVCR) is used to treat severe and rigid scoliosis. Purpose We aimed to compare the clinical results of APSF and APVCR for severe and rigid scoliosis. Study Design This is a retrospective, one-center, institutional review board-approved study. Patient Sample A total of 48 patients with severe and rigid scoliosis treated by APSF or APVCR were enrolled. Outcome Measures Comparisons between groups were made regarding the following variables: age at surgery, gender, etiology, flexibility of main curve, anterior release length, posterior fusion length, screw number, operation time, estimated blood loss, hospitalization time, follow-up duration, different radiological parameters, complication rate, and Scoliosis Research Society (SRS)-22 scores. Methods According to the operating technique, 48 patients with severe and rigid scoliosis were divided into two groups. In the first group, 26 patients were treated by APSF. In the second group, 22 patients were treated by APVCR. All patients had a minimum 2-year follow-up. The radiographic parameters as well as anterior release length, posterior fusion length, screw number, operation time, estimated blood loss, hospitalization time, complication rate, and demographic data were analyzed. Results There was no significant difference in age, gender, etiology, flexibility of main curve, anterior release length, posterior fusion length, screw number, and follow-up between the two groups. The APVCR group had longer operation and hospitalization time, and more blood loss. There was no significant difference in the preoperative main curve between the two groups, but the APVCR group had smaller main curve at postoperation and final follow-up, and higher correction rate at immediate postoperation and final follow-up. There was no significant difference in the preoperative, postoperative, and final follow-up thoracic kyphosis, and coronal and sagittal balance between the two groups. There was no significant difference in complication rate between the two groups. Analysis of the preoperative SRS-22 questionnaire revealed no difference between the two groups. At final follow-up, APSF and APVCR groups had similar scores in the function, pain, self-image, mental health, and satisfaction with the treatment domains. Conclusions Compared with APSF, treating severe and rigid scoliosis by APVCR means longer operation and hospitalization time, and more blood loss, but it allows better correction rate of main curve. Furthermore, SRS-22 questionnaire improvement scores were similar for both correction methods.

Dolomite is considered advantageous as bed material in fluidized bed gasification processes, due to its catalytic tar cracking and anti-sintering properties. However, in case of pressurized fluidized bed gasifiers, the use of dolomite is challenging. High temperature in the presence of steam favors the production of clean syngas due to the intensified cracking of tar in the presence of CaO, whereas it simultaneously increases the tendency of fragmentation of dolomite particles after full calcination. The present study was carried out to examine the influence of the properties of dolomite on the stability of dolomite in a pressurized fluidized bed gasifier, with the aim of determining criteria for dolomite selection. Glanshammar dolomite exhibited a better stability in the mechanical strength after calcination, compared to Sala dolomite. The corresponding change of micro-structure that occurred during dolomite chemical transformation was presented. The crystal pattern and Si distribution in the crystal lattice are the possible explanations for the superior performance of the Glanshammar dolomite compared to the Sala dolomite.

There are many different systems recommending upper instrumented vertebra (UIV) for Lenke type 2 adolescent idiopathic scoliosis (AIS), several of which suggest that all Lenke type 2 AIS patients should be fused to the second thoracic vertebra (T2). However, all previously proposed UIV selecting systems do not accurately predict postoperative shoulder balance. We investigated whether fusing to T2 could prevent postoperative shoulder imbalance and identified circumstances under which to fuse up to T2.We retrospectively collected all patients with typical Lenke type 2 AIS who received surgery by one spine surgeon in our hospital from 2010 to 2014. Lateral shoulder balance was assessed utilizing radiographic shoulder height difference (RSH), coracoid height difference (CHD), clavicle-rib intersection difference (CRID), and clavicle angle (CA). Medial shoulder balance was assessed by T1 tilt angle and first rib angle (FRA). Lateral shoulders were considered to be level if the absolute value of RSH was less than 10 millimeters. All patients were divided into two groups as follows: 1) T2 group: UIV of T2 (n=49); and 2) below-T2 group: UIV of T3 (n=24) or T4 (n=6). Patients were assessed before surgery and at final follow-up with a minimum follow-up duration of 24 months.Seventy-nine typical Lenke type 2 AIS patients were identified. Preoperative CHD and CA were significantly associated with postoperative lateral shoulder imbalance (both p=0.045), whereas the UIV level was not significantly associated with it. Both fusing to T2 and to below T2 could improve RSH (p0.001 and p=0.001, respectively). Fusing to T2 slightly worsened CHD, CRID, and CA at last follow-up (all p0.001), while fusing to below T2 improved these lateral shoulder balance parameters (p=0.042, p0.001, and p=0.007, respectively). For medial shoulder balance, fusing to below T2 worsened T1 tilt angle and FRA at last follow-up (p=0.025 and p0.001, respectively), while fusing to T2 effectively kept these medial shoulder parameters in balance. In addition, for patients with an elevated left border of T1, the T2 group had worse preoperative T1 tilt angle but gained better postoperative T1 tilt angle than the below-T2 group (p0.001 and p=0.040, respectively).Preoperative lateral shoulder balance, more so than the UIV level, can strongly influence postoperative lateral shoulder balance. Fusing to T2 can only effectively improve medial shoulder balance, not lateral shoulder balance (CHD, CRID, and CA). Moreover, a positive T1 tilt angle is an indicator for fusing to T2 to improve medial shoulder balance.

Objective One-stage posterior hemivertebral resection has been proven to be an effective, reliable surgical option for treating congenital scoliosis due to a single hemivertebra. To date, however, no studies of treating unbalanced multiple hemivertebrae have appeared. This study evaluated the efficacy and safety of one-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae. Patients and methods Altogether, we studied 15 patients with unbalanced multiple hemivertebrae who had undergone hemivertebral resection using the one-stage posterior approach with at least 2 years of follow-up. Clinical outcomes were assessed radiographically and with the Scoliosis Research Society-22 (SRS-22) score. Related complications were also recorded. Results The mean Cobb angle of the main curve was 62.4° (46°–98°) before surgery and 18.2° (9°–33°) at the most recent follow-up (average correction 73.3%). The compensatory cranial curve was corrected from 28.5° (11°–52°) to 9.1° (0°–30°) (average correction 70.0%). The compensatory caudal curve was corrected from 31.6° (14°–54°) to 6.9°(0°–19°) (average correction 79.1%). The segmental kyphosis/lordosis was corrected from 41.1° (−40° to 98°) to 12.3° (−25° to 41°) (average correction 65.5%). The mean growth rate of the T1-S1 length in immature patients was 9.8 mm/year during the follow-up period. Health-related quality of life (SRS-22 score) had significantly improved. Complications include one wound infection and one developing deformity. Conclusion One-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae provides good radiographic and clinical outcomes with no severe complications when performed by an experienced surgeon. Longer follow-up to detect late complications is obligatory.

Currently, polylactide is the most popular material used to made bioabsorbable cages but too-quick degradation and osteolysis around the cage have been reported in the literature. This study evaluated the fusion effect, biomechanical stability, and histologic characteristics of a novel bioabsorbable multiamino acid copolymer/nanohydroxyapatite/calcium sulfate (MAACP/n-HA/CS) interbody cage in a goat model of anterior cervical discectomy and fusion.A total of 24 goats underwent C3/C4 discectomy and fusion with 3 groups of intervertebral implants: MAACP/n-HA/CS cage group (n = 8), titanium cage group (n = 8), and autologous tricortical iliac crest bone group (n = 8). Disc space height and lordosis angle were measured pre- and postoperatively and after 4, 12, and 24 weeks. Range of motion (ROM) was evaluated through biomechanical testing. Histologic analysis was performed to evaluate fusion status and to detect any foreign body reactions associated with the bioabsorbable cages.At 12 and 24 weeks, disc space height in MAACP/n-HA/CS cage group was greater than that of titanium cage group and tricortical iliac crest group (P0.05). Lordosis angle in MAACP/n-HA/CS cage group and titanium cage group were lower than that of tricortical iliac crest group (P0.05). Biomechanical test showed that ROM did not differ significantly between MAACP/n-HA/CS cage group and titanium cage group, whereas the value of ROM in bone graft group was the largest. Histologic evaluation showed a better interbody fusion in the MAACP/n-HA/CS cage group than in the other 2 groups. MAACP/n-HA/CS cage surface degraded and was absorbed at 24 weeks. All MAACP/n-HA/CS cages showed excellent biocompatibility.MAACP/n-HA/CS cages can provide good fusion effect, enough biomechanical stability, and integrate closely with the surrounding bone.

Background: Proximal junctional kyphosis is a common complication after posterior fusion in adolescent idiopathic scoliosis patients, and was correlated with postoperative change of thoracic kyphosis. However, no previous literature has evaluated the correlation of PJK with thoracervical parameters in the AIS patients. Methods: Data from 61 patients who underwent posterior fusion for Lenke 5C AIS and had 2 years of follow-up were retrospectively reviewed. Patients were fused higher than two levels above the upper-end-vertebra in the extended fusion group (n=32), whereas they were fused below or at UEV+2 in the TL/L fusion group (n=29). Results: During an average follow-up of 32.5 months, 14/61 patients had PJK. The extended fusion group had a greater incidence of PJK than the TL/L fusion group did (11/32 vs. 3/29,P = 0.03) and a significant more decrease of TK than the TL/L group(p72° with extended fusion was a risk factor for PJK at final follow-up. The SRS-22 score did not significantly differ between the extended fusion and TL/L fusion groups. Conclusions: TIA could be a predictor of PJK. In Lenke 5C AIS patients, those with TIA >72° were more likely to develop PJK. And extended fusion in patients with Lenke 5C adolescent idiopathic scoliosis may be at an increased risk of proximal junctional kyphosis.

Dysphagia is a common postoperative complication in patients undergoing occipitocervical fusion (OCF). Previous studies had proposed the use of two measures-the occipital to C2 angle (O-C2a) and the occipital and external acoustic meatus to axis angle (O-EAa)-to predict postoperative dysphagia after OCF. However, these studies had small sample sizes and the predictive abilities of both measures are still not clear.To evaluate the predictive ability of O-EAa and O-C2a for dysphagia after OCF.A retrospective clinical study.A total of 109 consecutive patients who had undergone OCF.Presence of postoperative dysphagia, O-C2a, C2 tilting angle (C2Ta), O-EAa, and the narrowest oropharyngeal airway space (nPAS).Between April 2010 and June 2018, 109 consecutive patients who had undergone OCF were reviewed. Patients were divided into two groups according to the presence of postoperative dysphagia. Radiographic measurements, including O-C2a, C2Ta, O-EAa, and nPAS, were evaluated at preoperative and 1 month postoperative and the findings were compared. Simple linear regression was used to measure the correlations between the parameters and the presence of dysphagia, and the correlations within the parameters. Multiple regression analysis was used to examine the variables that affected the change of nPAS (dnPAS%). Sensitivity and specificity analyses were used to evaluate the effectiveness of the previously proposed measures ("O-C2a change≤-5°" and "postoperative O-EAa100°") for prediction of post-OCF dysphagia.The incidence of dysphagia after OCF was 26.6% (29/109). Preoperative values for the radiographic parameters were similar between patients with and without dysphagia. In the dysphagia group, both O-C2a and O-EAa values showed a dramatic decrease after surgery, which was accompanied by a decrease in nPAS. Postoperative O-C2a, O-EAa, and nPAS in the dysphagia group were significantly smaller than those in the nondysphagia group (p.05). The changes in O-EAa, O-C2a, and nPAS showed a linear correlation with the presence of dysphagia (p.05). In addition, linear correlations were found between two of the three parameters. Multiple regression showed the change of O-C2a and O-EAa were significant predictors for dnPAS% (β=0.200, p=.022 and β=0.549, p=.000). The sensitivity and specificity of "O-C2a change≤-5°" in predicting dysphagia were 75.9% and 80.0% respectively, and those of "postoperative O-EAa100°" were 75.9% and 62.5%, respectively. However, the sensitivity of the combination of these two values in predicting postoperative dysphagia was as high as 96.6%.Both O-EAa and O-C2a could be critical predictors for postoperative dysphagia. During surgery, ensuring that the O-EAa exceeds 100° and simultaneously avoiding an O-C2a reduction greater than 5° could effectively avert postoperative dysphagia.

To investigate airway development and airway resistance by computed tomographic three-dimensional (3D) reconstruction of the bronchial tree in patients with adolescent idiopathic scoliosis (AIS). We evaluated factors predicting postoperative respiratory complications to provide timely treatment, prevent complications, and improve operative and anesthetic safety. From August 2015 to August 2017, 53 AIS patients with a mean age of 15.4 years (range 10–20 years) were included in this study. Scoliotic parameters on radiographs were analyzed. Airway resistance was obtained by pulmonary function testing. All patients’ pulmonary bronchial trees were 3D-reconstructed via chest thin layer computed tomography to explore the correlation between the spinal–thoracic deformity parameters and airway resistance. Correlations between scoliotic parameters and airway development parameters were not statistically significant (P > 0.05). The scoliotic parameters such as Cobb angle, apical vertebral translation, rotation angle to sagittal plane, rotation angle to middle line, and apical vertebral body–rib ratio (AVB-R) were positively correlated with tracheal bifurcation angle (R2: 0.429, 0.374, 0.430, 0.504, and 0.414, respectively; P

Despite extensive research, our understanding of the dolomite calcination mechanism remains unclear, especially concerning how dolomite calcination is influenced by a change in H2O and CO2 partial pressure under high-pressure conditions. In this study, dolomite calcination behaviors and mechanisms at different H2O and CO2 partial pressures were investigated using thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy. Under dry thermal conditions, CO2 has a delaying effect on dolomite calcination; however, this effect is independent of CO2 partial pressure, indicating that the calcination could be controlled by the CO2 adsorption capacity on dolomite active sites. In an H2O atmosphere, calcination might begin at a low temperature due to the adsorption of H2O on active sites and then be controlled by the dissociation of HCO 3 − . A delaying effect of H2O was also observed, with the H2O partial pressure being lower than the CO2 partial pressure in an H2O and CO2 mixture. This could be attributed to the formation of CO32− via 2OH− + CO2 = CO32− + H2O. A model was developed to predict the dolomite conversion time under isothermal conditions. A process window considering the effect of operating variables on the conversion time at 550–1000 °C and H2O partial pressures of 1–20 bar is presented.

Posterior hemivertebra resection with short fusion has gradually become the mainstream treatment for the congenital scoliosis due to single fully segmented hemivertebra. A kind of unexpected emerging S-shaped scoliosis was found secondary to this surgery, and that has not been reported yet.The aim of the present study was to analyze the possible pathogenesis, clinical feature, and treatment of the emerging S-shaped scoliosis after posterior hemivertebra resection and short fusion.This study is a retrospective case series.A total of 128 patients participated.Preoperative and postoperative whole spine radiographs were used to measure the Cobb angle of main curve, compensatory curve, and emerging curves. And the hemivertebra location, the fused segment, the apical and ending vertebrae of postoperative-emerging curve (and preoperative compensatory curves) were assessed.Both the demographics and radiographic data were reviewed. Postoperative-emerging scoliosis was defined as the curve with an increasing angle of 20° and an apical vertebra locating at least two levels away from fusion region.Of the 128 patients, 9 (7%) showed postoperative-emerging S-shaped scoliosis. The mean age was 11.4 years old. The mean main curve was 36.1±14.4° preoperatively and been significantly corrected to 6.9±6.1° (p.001). No significant difference was found in the main curve, kyphosis, coronal balance, or sagittal balance during follow-up. The emerging scoliosis occurred at 3 months (in four patients) or 6 months (in five patients) after initial surgery with an average angle of 42.6±12.9° at last follow-up. All patients underwent bracing or observation when the S-shaped scoliosis was arising, and four patients underwent a revision surgery because of deformity developing.The emerging S-shaped scoliosis was an extraordinary complication that may be developing from the preoperative compensatory scoliosis and usually occurred at 3-6 months after hemivertebra resection. The feature of these curves was similar to the adolescent idiopathic scoliosis (AIS) and brace or revision surgeries were suitable for therapy.

In this study, the anti-agglomeration abilities of Ca- and Mg-containing bed materials, including dolomite and magnesite, in a pressurized bubbling fluidized bed gasifier using pine pellets and birch chips as feedstock, is investigated. The most typical bed material—silica sand—was also included as a reference for comparison. The sustainability of the operation was evaluated via analyzing the temperatures at different levels along the bed height. During the performances, the aim was to keep the temperature at the bottom zone of the reactor at around 870 °C. However, the success highly depends on the bed materials used in the bed and the temperature can vary significantly in case of agglomeration or bad mixing of bed materials and char particles. Both Glanshammar and Sala dolomites performed well with no observed agglomeration tendencies. In case of magnesite, the bed exhibited a high agglomeration tendency. Silica sand displayed the most severe agglomeration among all bed materials, even when birch chips with a low silica content was fed at a relatively low temperature. The solid samples of all the bed materials were inspected by light microscopy and Scanning Electron Microscopy (SEM). The Energy Dispersive Spectroscopy (EDS) detector was used to detect the elemental distribution in the surface. The crystal chemical structure was analyzed using X-ray Diffraction (XRD). Magnesite agglomerates glued together by big molten ash particles. There was no coating layer detected on magnesite particles at bed temperatures – below 870 °C. But when the temperature was above 1000 °C, a significant amount of small molten ash particles was deposited on the magnesite particles, indicating a pronounced tendency for formation of a coating layer in case of long-term operation. An increasing trend of Si on the surface of dolomite particles was observed. Simultaneously, potassium deposition on the surface is not obvious. The analyses, based on the XRD diffraction and the K2O–SiO2–MgO and K2O–SiO2–CaO ternary diagrams, suggest that the observed decreases in the risks for agglomeration using dolomite, cannot be attributed to formation of alkali-containing compounds with higher melting points, but to the reaction between dolomite and silica, consuming a considerable portion of silicon and thus hinder the formation of low-melting potassium silicate, as well as its ability to stabilize the temperatures under pressurized conditions.

The vascular system particularly endothelium is sensitive to ischemia-reperfusion (I/R) injury, which is a big challenge in surgical practices and many vascular disorders. In the present study, we reported the global gene expression changes in a 2-h ischemia and 4-h reperfusion injury induced in the hind limb vessels of rhesus monkeys ( Macaca mulatta ) using microarray technique. Results: The histological results showed abnormal morphology of endothelial cells after 2-h ischemia and the hematological detection found slightly extension of coagulation time after I/R treatment. Furthermore, we found distinct alterations in gene expression patterns during I/R process. These identified genes are mostly involved in inflammation, immune response, apoptosis, and cell stress signaling pathways. The significantly up-regulated genes included IL-6 , regulator of G-protein signaling 8 , selectin E , and metallothionein 2A , et al. Whist, the robustly down-regulated genes included NECAP endocytosis associated 2 , transglutaminase 2 , and fibronectin 1 , et al. Conclusion: Our results indicate that inflammation, primarily characterized by gene expression changes of cytokines and chemokines is the most important event in the early stage of I/R injury in blood vessels.

To discuss the effectiveness of atlantoaxial joint release through anterior retrophayngeal approach and staged posterior reduction fixation and fusion for irreducible atlantoaxial dislocation (IAAD).Fifteen patients with IAAD (9 males, 6 females), aged 14-53 years (mean, 31.4 years) were included in the study. The disease duration was 3 months to 17 years (mean, 5.7 years). IAAD was attributed to trauma in 13 cases, and 2 cases were caused by congenital odontoid disconnection. Preoperative imaging examination showed atlantoaxial dislocation and could not be reset automatically in functional position. The preoperative visual analogue scale (VAS) score was 3-7 (mean, 4.1), and the preoperative Japanese Orthopaedic Association (JOA) score was 10-17 (mean, 13.8). All patients received atlantoaxial joint release through anterior retrophayngeal approach and staged posterior fixation and fusion.Anatomical reduction was achieved in all 15 patients, and the alignment of atlantoaxial joints was restored. After operation, the neck pain and neurological symptom were partially or fully improved in all patients, without deterioration of neurological function. One patient developed pharyngeal discomfort and cough after one-stage operation, 4 patients developed pharyngeal discomfort and foreign body sensation after operation, and 2 patients developed pin-path lipstick swelling during skull traction. All patients were cured by symptomatic treatment. No pulmonary infection, pressure ulcers, venous thrombosis, and incision infection was found during the treatment. All 15 patients were followed up 24-36 months, with an average of 28.6 months. Bony fusion was achieved in all patients, and the fusion time was 3-5 months, with an average of 3.6 months. At last follow-up, the VAS score was 0-2 (mean, 0.5) and the JOA score was 13-17 (mean, 15.9). There was no dislocation, recurrence, or other abnormal sign in the cervical X-ray films and three-dimensional CT.Anatomical reduction can be achieved by atlantoaxial joint release through anterior retrophayngeal approach and staged posterior fixation and fusion for treating IAAD. It is an optional procedure for IAAD.探讨经颈前咽后入路前路松解二期后路复位融合内固定术治疗难复性寰枢关节脱位的疗效。.2012 年 2 月—2016 年 8 月，收治 15 例难复性寰枢关节脱位患者。男 9 例，女 6 例；年龄 14～53 岁，平均 31.4 岁。病程 3 个月～17 年，平均 5.7 年。其中因外伤后继发寰枢关节脱位 13 例，先天性齿状突不连继发寰枢关节脱位 2 例。术前影像学检查均提示寰枢关节脱位，在功能位上无法自行复位。疼痛视觉模拟评分（VAS）为 3～7 分，平均 4.1 分；日本骨科协会（JOA）评分为 10～17 分，平均 13.8 分。采用一期经颈前咽后入路前路松解后，继续颅骨牵引，二期经后路复位植骨融合内固定术治疗。.所有患者均达解剖复位，恢复寰枢关节正常序列，术后颈痛及神经症状均部分改善甚至完全恢复，均未出现脊髓损伤加重。 1 例一期术后出现咽部不适、饮水呛咳，4 例术后有不同程度的咽部不适、异物感，2 例于颅骨牵引过程中出现钉道口红肿，均行对症处理后治愈。治疗过程中未出现肺部感染、压疮、下肢静脉血栓形成、切口感染等。15 例患者均获随访，随访时间 24～36 个月，平均 28.6 个月。植骨均获骨性融合，融合时间 3～5 个月，平均 3.6 个月。末次随访时 VAS 评分为 0～2 分，平均 0.5 分；JOA 评分为 13～17 分，平均 15.9 分。末次随访时复查颈椎 X 线片及三维 CT 均未见脱位复发及其他异常征象。.采用一期经颈前咽后入路前方松解、二期经后路植骨融合内固定术治疗难复性寰枢关节脱位可达到解剖复位，是一种可供选择的术式。.

The nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is a novel biomimetic nonmetal cage device that is now used in some medical centers, while the titanium mesh cage (TMC) is a typical metal cage device that has been widely used for decades. This study was performed to compare the long-term outcomes of these two different cages in patients undergoing anterior cervical corpectomy.This retrospective study involved 107 patients who underwent single-level anterior corpectomy using either a TMC (n = 52) or an n-HA/PA66 cage (n = 55) for treatment of cervical degenerative disease with a minimum follow-up of 8 years. Their radiographic data (cage subsidence, fusion status, segmental sagittal alignment, and cervical spine degeneration) and clinical data [visual analog scale (VAS) and Japanese Orthopedic Association (JOA) scores] were evaluated preoperatively, postoperatively, and at the final follow-up.The mean duration of follow-up was 103.6 ± 6.3 months in the n-HA/PA66 group and 102.4 ± 4.6 months in the TMC group. The n-HA/PA66 group and the TMC group had similar final fusion rates (97% vs. 94%, respectively). The final n-HA/PA66 cage subsidence was 2.4 ± 1.0 mm with 18.2% subsidence of3 mm, which was significantly lower than the respective 3.0 ± 0.7 mm and 40.4% for the TMC (p 0.01). The n-HA/PA66 group also had better JOA scores than the TMC group (p 0.01). No significant difference in the segmental sagittal alignment, cervical lordosis, or VAS score was observed between the two groups (p = 0.18, 0.42, and 0.17, respectively).The n-HA/PA66 cage is associated with excellent radiographic fusion, lower subsidence and better clinical outcomes than the TMC within 8 years after single-level anterior cervical corpectomy. With the addtional benefit of radiolucency, the n-HA/PA66 cage could be superior to the TMC in anterior cervical construction.

Background Extended fusion can be performed in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) with a large and relatively rigid thoracic curve. Progression of the thoracic curve is related to coronal imbalance. We aimed to determine the correlation between the upper instrumented vertebra choice and coronal balance in patients with Lenke 5C AIS. Methods A total of 61 patients with Lenke 5C AIS underwent posterior fusion from 2009 to 2015 in a single institution with ≥2 years of follow-up data available. The extended fusion group (n = 32) and thoracolumbar/lumbar (TL/L) fusion group (n = 29) were compared for the correction rates for the main TL/L and thoracic curves, coronal balance, upper end vertebra (UEV) tilt, and Scoliosis Research Society-22 questionnaire score. Results Both groups had excellent correction of the main TL/L curve, and the extended fusion group had a significantly greater correction rate of the thoracic curve than the TL/L fusion group (70.2% vs. 57.3%). The incidence of coronal imbalance was similar in both groups. The spontaneous change in UEV tilt was associated with the change in coronal balance from the first to the final follow-up examination. In the TL/L fusion group, the increase in UEV tilt from the first to final follow-up visit resulted in improved coronal balance at the final follow-up examination. Both groups had similar Scoliosis Research Society-22 questionnaire scores at 2 years postoperatively. Conclusions In patients with Lenke 5C AIS, thoracic curve fusion results in better correction of the thoracic curve but no improvement in coronal balance. With TL/L fusion, a postoperative UEV tilt >5° leads to better coronal balance.

Background Lenke 5 AIS is a kind of three-dimensional deformity and literature reported it usually accompany with coronal or/and sagittal imbalance. However, the postoperative coronal and sagittal balance in these patients has rarely be analyzed previously and the predict factors for postoperative trunk balance are still unclear. To synthetically analysis coronal and sagittal balance of Lenke 5 AIS patients simultaneously and found out predict factors for postoperative coronal or/and sagittal imbalance. Methods Fifty-six Lenke 5 AIS patients who underwent posterior surgery and be followed up more than 2 years were included in this study. Coronal parameters included main curve Cobb angle, lumbosacral hemi-curve Cobb angle, preoperative LEV/LIV tilt and translation and C7-CSVL distance; While sagittal parameters included pelvic incidence(PI), sacral slope(SS), pelvic tilt(PT), lumbar lordosis(LL), thoracic kyphosis(TK), and sagittal vertical axis(SVA). Coronal imbalance was defined as C7-CSVL> 20 mm, and sagittal imbalance defined as (1) SVA > 40 mm or (2) PT 20° or (3) PI-LL > 10°. And relative parameters were compared between balance and imbalance group to find out predict factors. Results All seven final coronal imbalance patients occurred in LIV = L5 group. Preoperative LIV tilt(11.4°) and translation(5.2 mm) in coronal imbalance group were abnormally lower than balance group (21.7° and 15.7 mm respectively). Eighteen patients performed final sagittal imbalance. The PI in these patients (37.7°) was significantly lower than balance group (48.0°). And most of finial sagittal imbalance patients also occurred in LIV = L5 group. Conclusions LIV = L5 as a threshold point, represents higher risk of postoperative coronal and/or sagittal imbalance. Besides, large LEV-S1 curve in reduce-bending film and small PI is directly related to final coronal imbalance and sagittal imbalance respectively.

Background Hemimetameric segmental shift (HMMS) is defined as ≥2 contralateral hemivertebrae (HV) that are separated by at least 1 normal vertebra. Theoretically, the 2 HV tend to balance each other to produce minor spine deformities. However, curve progression has still been observed in HMMS. No research has yet specifically studied its surgical treatment. This study aimed to report efficacy of HV resection for HMMS. Methods From 2009 to 2015, 15 patients (5 male and 10 female) with HMMS underwent HV resection in our department. Average age at the time of surgery was 10.5 ± 4.7 years, and mean length of follow-up was 38.5 ± 7.1 months. Clinical outcomes and related complications were assessed by reviewing the medical records, operative notes, radiographic data, and scores on the Scoliosis Research Society-22 questionnaire. Results The segmental curve was 45.1° ± 10.6° preoperatively, 14.3° ± 7.8° postoperatively, and 15.3° ± 7.6° at the latest follow-up. The cranial compensatory curve was 17.1° ± 11.9°, 8.9° ± 6.3°, and 7.8° ± 6.5°. The caudal compensatory curve was 12.0° ± 11.0°, 4.5° ± 4.8°, and 4.3° ± 5.0°. Spinal balance was significantly improved in both coronal and sagittal planes and remained stable until the latest follow-up. Three domains of the Scoliosis Research Society-22 questionnaire, including general self-image, mental health, and satisfaction, were significantly improved at the latest follow-up compared with preoperative status. Conclusions HV resection is a safe and effective treatment for HMMS that causes progressive or severe deformity.

To explore the feasibility of co-transduction and co-expression of Nogo extracellular peptide residues 1-40 (NEP1-40) gene and neurotrophin 3 (NT-3) gene into neural stem cells (NSCs).NSCs were derived from the cortex tissue of Sprague Dawley rat embryo. The experiment included 5 groups: no-load lentiviral vector transducted NSCs (group A), NEP1-40 transducted NSCs (group B), NT-3 transducted NSCs (group C), NEP1-40 and NT-3 corporately transducted NSCs (group D), and blank control (group E). Target genes were transducted into NSCs by lentiviral vectors of different multiplicity of infection (MOI; 5, 10, 15) for different time (24, 48, 72 hours). Fluorescent microscope was used to observe the expression of fluorescence protein and acquire the optimum MOI and optimum collection time. Real-time fluorescence quantitative PCR and Western blot tests were utilized to evaluate the gene expressions of NEP1-40 and NT-3 in NSCs and protein expressions of NEP1-40 and NT-3 in NSCs and in culture medium.The optimum MOI for both target gene was 10 and the optimum collection time was 48 hours. The real-time fluorescence quantitative PCR and Western blot results showed that the mRNA and protein relative expressions of NEP1-40 in groups B and D were significantly higher than those in groups A and C (NEP1-40 and NT-3 gene can be successfully co-transducted into NSCs by the mediation of lentiviral vector. The expressions of the two target genes are stable and have no auxo-action or antagonism between each other.通过慢病毒载体将 NEP1-40（Nogo extracellular peptide residues 1-40）及神经营养因子 3（neurotrophin 3，NT-3）双基因转染入神经干细胞（neural stem cells，NSCs）内进行表达，探讨 NEP1-40 及 NT-3 双基因转染 NSCs 的可行性，为 NSCs 体内实验奠定基础。.将 SD 大鼠胚胎室管膜区 NSCs 采用空载慢病毒载体（A 组）、NEP1-40 慢病毒载体（B 组）、NT-3 慢病毒载体（C 组）及 NEP1-40 和 NT-3 慢病毒载体（D 组）进行转染，以未转染病毒的细胞作为对照组（E 组）。用感染复数（multiplicity of infection，MOI）为 5、10、15 的慢病毒载体分别转染 24、48、72 h，荧光显微镜观察转染后细胞内荧光表达情况，确定慢病毒载体的最佳 MOI 和收样时间。再分别通过实时荧光定量 PCR 及 Western blot，检测转染后细胞中 NEP1-40 及 NT-3 基因的表达，以及细胞和培养基中 NEP1-40 及 NT-3 蛋白的表达。.荧光显微镜观察示，MOI 为 10 时 NEP1-40 和 NT-3 基因慢病毒载体在 NSCs 内转染率最高，最佳时间为转染 48 h 时。实时荧光定量 PCR 及 Western blot 检测示，B、D 组 NEP1-40 mRNA 相对表达量和蛋白相对表达量均显著高于 A、C 组，差异有统计学意义（通过慢病毒载体可将 NEP1-40 及 NT-3 双基因成功转染入 NSCs 内，在 NSCs 内稳定表达，且两种目的基因在表达过程中无相互拮抗或促进作用。.

To review the research progress of pathogenesis mechanism of spinal deformity in neurofibromatosis type 1 (NF1).Recent literature concerning the pathogenesis mechanism of spinal deformity in NF1 was extensively reviewed, and current developments of the correction of spinal deformity and NF1 and the pathogenesis mechanism were summarized.The pathogenesis mechanism of spinal deformity in NF1 is not yet clearly known. Current theories include erosion and stress of neurofibromas, melatonin-related decreased contractility of paraspinal muscles, osteopenia and osteoporosis, sexual precocity and mesoderm dysplasia.The clinical manifestations of NF1 may cause the spinal deformities in patients with NF1. The research of pathogenesis mechanism of spinal deformity in NF1 will be conducive to further understanding, diagnosis and treatment of NF1-related spinal deformity.综述1型神经纤维瘤病（neurofibromatosis type 1,NF1）相关的脊柱畸形致病机制研究进展。.广泛查阅近年国内外有关NF1相关脊柱畸形致病机制的文献，对其与脊柱畸形的相互联系、相关致病机制及研究进展进行综述。.目前对于NF1患者发生脊柱畸形的致病机制尚未明确，可能与神经纤维瘤直接侵蚀与压迫、椎管内硬脊膜扩张、褪黑素导致的脊柱旁肌肉收缩力下降、骨量减少与骨质疏松、性早熟以及中胚层发育不良有关。.NF1患者的众多临床表现可能是导致其脊柱畸形发生的诱因，NF1相关脊柱畸形致病机制的研究将有助于对NF1脊柱畸形的认识、诊断和治疗。.

Background Choosing the fusion level for posterior fusion in patients with Lenke 5C adolescent idiopathic scoliosis (AIS) is highly associated with coronal balance. Previous studies indicated that in patients with lowest end vertebra tilt >25°, surgeons could extend distal fusion to avoid coronal imbalance (CIB). This study aimed to assess the risk factors for CIB in Lenke 5C scoliosis and to discuss how to select fusion level. Methods We reviewed 59 patients with Lenke 5C AIS in 1 institution with at least 2 years follow-up from 2010 to 2015. Preoperative and 3-month and 2-year postoperative follow-up radiographs were measured using several specific measurements related to coronal balance. Patients were categorized into an LEV (lower end vertebra) group and an LEV+1 group. Results CIB was found in 6/31 patients in the LEV+1 group at final follow-up and not found in the LEV group at the first or final follow-up. The C7 plumb line shifted to the convex side of the central sacral vertical line in 47/59 patients, including all of the 19 patients with CIB after surgery. Patients who underwent fusion at LEV+1 with >25° LEV tilt also showed poor results regarding CIB. Statistically, coronal balance at the final follow-up was correlated with preoperative bending lumbosacral hemicurve (P = 0.002) and all 6 patients with CIB had bending lumbosacral hemicurve >15°. No significant difference was found in Scoliosis Research Society–22 questionnaire scores between the 2 groups at 2-year-follow-up. Conclusions Distal fusion extension at LEV+1 is more likely to result in CIB at the first and final follow-up, especially when the bending lumbosacral hemicurve is >15°. Fusion at LEV+1 should not be chosen when LEV is at L4.

To evaluate the outcome and complications of anterior release, posterior internal distraction and subsequent posterior spinal fusion for the treatment of severe kyphoscoliosis.The medical records and spinal imaging of 17 consecutive severe kyphoscoliosis patients who underwent anterior release, posterior internal distraction and subsequent posterior spinal fusion were reviewed.Patients underwent spinal deformity correction at the mean age of 22.6 ± 8.4 years (range 15-44 years) with mean follow-up of 37.4 ± 12.0 months (range 24-60 months). The preoperative thoracic kyphosis of 83.5° ± 16.3° (range 60°-115°) was corrected to 37.5° ± 7.9° (range 20°-49°) at the final follow-up. The preoperative major curve of 110.1° ± 16.8° (range 92°-145°) was corrected to 33.5° ± 13.9° (range 12°-63°) at the final follow-up, with a scoliosis correction of 70.3 %. At the most recent follow-up, the correction rate of proximal thoracic curve and thoracolumbar or lumbar curve was 57.1 and 74.8 %, respectively. Transient dyspnoea occurred in one patient after the initial surgery and subsequently resolved. No ventilator support was needed. Three patients complained the pain of concave soft tissue after the first distraction. There were no neurological complications or any deep wound infections. No complication of instrumentation was found at final follow-up.In the treatment of severe kyphoscoliosis, anterior release, posterior internal distraction and subsequent posterior spinal fusion, which obviates three-column osteotomy, is a good alternative correction method.

Heat transfer models using to estimate the effective thermal conductivity have been developed and included in a model for the pyrolysis of refuse-derived fuel or solid recovered fuel particles composed of cardboard and polyethylene. Both the predictions from the Kunii and Smith model and the Breitbach and Barthels model were presented and compared with the experimental data. The possible mechanisms of heat transfer in the porous solid particles were discussed. Compared to the conduction mode by solid matrix and gas phase, radiation heat flux between the neighboring voids and from particle surface and neighboring particle surface are considered as the main mechanisms at the temperatures presented in this paper. The porosity has been reported to serve as an important role in the accurate estimation of the radiation exchange factor for the radiation term in heat transfer model in a highly porous medium. Refuse-derived fuel particle with a high plastic concentration exhibits a rapid increase of porosity with the continuous thermal conversion of plastic. Thus, a coefficient as a function of porosity was applied to the radiation exchange factor in the Kunii and Smith model, which was constructed and based on a simplified model of heat transfer in packed bed. Moreover, the effect of the contact surface area between solid particles on the heat transfer of conduction mode was also considered in the Breitbach and Barthels model. Both modified models were further validated with experimental results obtained at different temperature, with different PE content and initial porosity.

Study design A retrospective study. Objective To investigate the preoperative spinopelvic sagittal alignment in Lenke 5 patients with adolescent idiopathic scoliosis (AIS), and analyze how it alters after posterior correction. Summary of background data The structural thoracolumbar or lumbar curve may change the local sagittal alignment thereby altering the sagittal balance in Lenke 5 patients with AIS. However, few studies have evaluated the spinopelvic sagittal alignment before and after the surgery in these patients. Methods Forty-eight Lenke 5 patients with AIS who underwent posterior correction and fusion were included in this study. Preoperative and postoperative radiographs were reviewed measuring both the coronal and sagittal parameters. Three pelvic sagittal states (anteverted, normal, or retroverted) were evaluated according to the magnitude relationship of individual pelvic tilt with pelvic incidence (PI). Both the coronal and sagittal parameters between different pelvic sagittal states were compared. The alterations of these parameters by surgery would also be analyzed. Results The mean follow-up was 1.8 years. Preoperatively, the mean PI was 44.3° with a pelvic tilt of 4.1°. There was 48% patients showing the anteverted pelvis, whereas the remaining 52% showing normal. The patients with anteverted pelvis showed a smaller PI and more distal lower end vertebra than normal pelvis ones. Logistic regression analysis revealed PI (odds ratio [OR] = 0.62, P = 0.024) and lower end vertebra (OR = 2.1, P = 0.037) were significantly associated with the risk of developing anteverted pelvis. The pelvic tilt was significantly increased and 61% of patients with preoperative anteverted pelvis had recovered. Logistic regression analysis revealed PI (OR = 0.7, P = 0.034) and lower instrumented vertebra (OR = 6.5, P = 0.002) were significantly associated with the risk of postoperative uncovered of anteverted pelvis. Conclusion Anteverted pelvis appears in almost half of Lenke 5 patients with AIS, especially in who have smaller PI or distal lower end vertebra. The abnormal pelvic sagittal state will be generally corrected by posterior correction surgery except for patients with a PI less than 39° or a lower instrumented vertebra that extends to L5.

Objective Hemivertebrae (HV) located at the lower lumbar or lumbosacral region often produce early trunk imbalance and long compensatory curves. Because of the biomechanical characteristics of the lumbosacral junction, the rate of instrumentation failures at the region has always been high. Our study aimed to evaluate the results of posterior HV resection with lumbosacral fixation and fusion in the treatment of congenital scoliosis and to make a preliminary analysis of the possible risk factors for instrument failures. Patients and methods From 2010 to 2015, 17 patients (7 males and 10 females) with congenital scoliosis underwent HV resection with lumbosacral fixation and fusion in our department. The mean patient age was 13.2 ± 4.4 years at surgery, and the mean follow-up time was 37.6 ± 4.6 months. Clinical outcomes and related complications were assessed by reviewing medical records, operative notes, radiographic data, and scores on the SRS-22 questionnaire. Results The mean Cobb angle of the segmental curve was 37.5° ± 12.7° preoperatively, 7.9° ± 5.5° postoperatively, and 7.9° ± 5.3° at the latest follow-up. The mean Cobb angle of the cranial compensatory curve was 39.2° ± 17.2°, 9.1° ± 9.5°, and 9.5° ± 10.8°, respectively. Trunk balance was improved in both the coronal (59.6%) and sagittal (58.6%) planes after surgery, and remained stable at the latest follow-up. Three domains of SRS-22, including self-image, mental health, and satisfaction, were significantly improved at the latest follow-up compared with preoperative status. Complications included one transient neurologic impairment, one superficial wound infection, and two implant failures. Conclusions Early posterior HV resection with short lumbosacral fixation and fusion is effective in the treatment of HV located at lower lumbar or lumbosacral region. Delayed surgical intervention may lead to longer fusion and fixation. A long lumbosacral construct using only S1 pedicle screws as distal anchors tends to accompany a high rate of implant failures.

Background Context The efficacy of one-stage posterior pedicle screw instrument used in the treatment of non-dystrophic scoliosis in neurofibromatosis type I (NF-1) is unknown. Also, there is no study that has directly compared the results of spinal deformity correction between non-dystrophic scoliosis in NF-1 and adolescent idiopathic scoliosis (AIS). Purpose The objectives of this study were to study the efficacy of a one-stage posterior pedicle screw instrument used in the treatment of non-dystrophic scoliosis in NF-1 and to compare non-dystrophic scoliosis in NF-1 with matched AIS to illustrate the differences. Study Design This is a retrospective case control study. Patient Sample Fifteen patients with non-dystrophic scoliosis in NF-1 and 15 patients with AIS underwent a one-stage posterior surgery with the pedicle screw system. Outcome Measures Preoperative and postoperative whole-spine radiographs were used to determine coronal and sagittal Cobb angles. Also, the distance between the C7 plumb line and the center sacral vertical line and the sagittal vertebral axis was measured to assess spinal balance. The Scoliosis Research Society (SRS)-22 questionnaire was used to evaluate functional outcomes. Methods We matched 15 patients with non-dystrophic scoliosis in NF-1 with patients with AIS (ratio, 1:1) for age, sex, and degree of major deformity. The overall mean age was 13.4±2.0 and 14.0±2.1 years, respectively. The NF-1 group consisted of 10 boys and 5 girls, and the AIS group consisted of 9 boys and 6 girls. The mean follow-up was 37.6±3.9 and 33.5±5.0 months, respectively. The AIS group underwent end vertebra (EV) or EV+1 fusion. The NF-1 group underwent EV+1, 2, or 3 fusion. Both coronal and sagittal Cobb angles, trunk balance, operative time, blood loss, fusion levels, length of stay, and scores on the SRS-22 questionnaire were compared between the two groups. The study was supported by the National Natural Science Foundation of China (Grant No. 81401760). There were no study-specific conflict of interest-associated biases. Results The preoperative main curve magnitude was similar between the two groups; however, the flexibility of the NF-1 group tended to be less than that of the AIS group. The rate of correction of the main curve obtained surgically (79.8% compared with 81.1%) was similar in the NF-1 and AIS groups. There were no significant differences in the loss of correction between the two groups (p>.05). Also, there were no significant differences between the groups in operative time, blood loss, fusion levels, screw number, length of stay, trunk balance, and scores on the SRS-22. There were no serious complications related to surgery in both groups. Conclusions Despite the differences in preoperative flexibilities and fusion strategies, non-dystrophic scoliosis in NF-1 can be treated with a satisfied correction rate and progression rate similar to comparable AIS by using the one-stage posterior pedicle screw technique. Dural ectasia or thin pedicles in non-dystrophic scoliosis could make pedicle screw placement challenging.

Background: The treatment of the syrinx prior to correction of the scoliosis in syringomyelia-associated scoliosis (SMS) patients remains controversial. The aim of this study is to evaluate the role of the syrinx size in the management of SMS patients. Materials and Methods: This was a retrospective study of 36 SMS patients. They were divided into 2 groups: Group A (26 with a small syrinx, syrinx(S)/spinal cord(C) ratio ≤0.7) and Group B (10 with a large syrinx, S/C ratio >0.7). Patients with a large syrinx accepted prophylactic neurosurgery prior to scoliosis surgery. They were evaluated at baseline, 1-week and last follow-up after correction surgery for changes in curve correction, global coronal balance, thoracic kyphosis (TK), sagittal vertical axis (SVA), and Scoliosis Research Society (SRS)-22 scores. Results: The syrinx size of patients in Group A was significantly smaller than that of in Group B. The syrinx size was significantly decreased after prophylactic neurosurgery in Group B. The radiographic parameters of scoliosis at baseline, 1-week and last follow-up after scoliosis surgery were comparable between two groups. No abnormal signal was detected during the process of neuromonitoring in both groups. Pre- and postoperative SRS-22 scores were similar between two groups. Conclusions: Prophylactic neurosurgery may be beneficial for decreasing the risk of correction surgery in SMS patients with large syrinx (S/C ratio >0.7). After the intervention of syrinx prior to scoliosis correction, SMS patients with large syrinx could obtain similar clinical and radiographic outcomes of treatment with pedicle-screw-based spinal instrumentation and fusion compared to the patients with small syrinx.

With the aims of improving the understanding of the use of dolomite bed materials in a fluidized bed (FB) gasifier, dolomite primary fragmentation behaviors and mechanisms at elevated temperatures were thoroughly investigated by means of quantitative analysis of particles production, size distribution, and particles shape (in terms of HS circularity and convexity). Crystalline Glanshammar and amorphous Sala dolomites of different original particle sizes (300–350 μm, 350–500 μm, and 500–1000 μm) were treated under various conditions, such as temperatures of 650, 750, and 950 °C and gas conditions of N2, N2 & steam, and H2O & CO2. Crystalline Glanshammar dolomite exhibited severe fragmentation, while amorphous Sala dolomite only fragmented slightly. Fragmentation mechanisms were proposed for amorphous and crystalline dolomite. In case of the Glanshammar dolomite, the release of H2O trapped in the crystal lattices and trace level of CO2 at structure defects, contributed to 10% and 55% of the primary fragmentation, respectively. The presence of CO2 can significantly mitigate the fragmentation of crystalline Glanshammar dolomite, which is probably either due to the prevention of CO2− dissociation at the defects or filling of cations by interchanging CO2− with the dolomite, consequently, allowing for a stabilization of dolomite structure. The analysis shows that elutriation in fluidized bed gasifier can be reduced significantly when either using amorphous Sala dolomite as bed material or treatment of the Glanshammar dolomite in the presence of CO2 before its utilization in a fluidized bed.