Cervical Sagittal Alignment and Related Factor Analysis and Prediction Model in Patients Undergoing Revision Surgery After Anterior Cervical Fusion.

INTRODUCTION: Patients with myelopathy or radiculopathy commonly undergo anterior cervical fusion surgery (ACFS), which has a notable failure rate on occasion. The goal of this study was to compare revision and nonrevision surgery patients in cervical sagittal alignment (CSA) subsequent to ACFS; additionally, to identify the best CSA parameters for predicting clinical outcome after ACFS; and furthermore, to create an equation model to assist surgeons in making decisions on patients undergoing ACFS. METHODS: The data of 99 patients with symptomatic cervical myelopathy/radiculopathy who underwent ACFS were analyzed. Patients were divided into group A (underwent revision surgery after the first surgery failed) and group B (underwent only the first surgery). We measured and analyzed both preoperative and postoperative CSA parameters, including C2 slope, T1 slope, cervical lordosis C2-C7 (CL), C2-C7 sagittal vertical axis (C2C7 SVA), occiput-C2 lordosis angle (C0-C2), and chin brow vertical angle, and we further computed the correlation between the CSA parameters and created a prediction model. RESULTS: The (T1S-CL)-C2S mismatch differed significantly between groups A and B ([9.95 ± 9.95]0, [3.79 ± 6.58]0, P < 0.05, respectively). A significant correlation was observed between C2 slope and T1CL in group B relative to group A postoperatively (R2 = 0.42 versus R2 = 0.09, respectively). Compared with group B, patients in group A had significantly higher C2C7SVA values, more levels of fusion, and more smokers. The sensitivity, specificity, accuracy, and discrimination of the model were, respectively, 73.5%, 84%, 78.8%, and 85.65%. CONCLUSION: The causes of revision surgery in cervical myelopathic patients after anterior cervical corpectomy and fusion/anterior cervical diskectomy and fusion are multifactorial. (T1S-CL)-C2S mismatch and high C2C7SVA are the best cervical sagittal parameters that increase the odds of revision surgery, and the effect is more enhanced when comorbidities such as smoking, low bone-mineral density, and increased levels of fusion are taken into account.

Multi-rod posterior correction only with halo-femoral traction for the management of adult neuromuscular scoliosis (> 100°) with severe pelvic obliquity: a minimum 5-year follow-up.

BACKGROUND: Many patients with neuromuscular scoliosis (NMS) experience a variety of difficult medical problems that aggravate the development effects of progressive scoliosis and pelvic obliquity (PO). The objective of the current study was to assess the safety and effectiveness of multi-rod posterior correction only (MRPCO) with halo-femoral traction (HFT) for the management of adult NMS (> 100°) with severe PO. METHODS: From 2012 to 2017, 13 adult patients who suffered from NMS (> 100°) with severe PO underwent MRPCO with HFT. The radiography parameters in a sitting position, such as the coronal Cobb angle of the main curve, the PO and the trunk shift (TS), were measured at the preoperative, postoperative and final follow-up stages. The preoperative and final follow-up assessment of the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) was taken. RESULTS: The average follow-up span was 68.15 ± 6.78 months. There was decreased postoperative coronal Cobb angle with an average mean of 125.24° ± 11.78° to 47.55° ± 12.10°, with a correction rate of 62.43%; the PO was reduced to 6.25° ± 1.63° from 36.93° ± 4.25° with a correction rate of 83.07%; the TS was reduced to 2.41 cm ± 1.40 cm from 9.19 cm ± 3.07 cm. There was significant improvement in all parameters compared to the preoperative data. The VAS score reduced from 4.77 ± 0.93 to 0.69 ± 0.75, and the ODI score reduced from 65.38 ± 16.80 to 28.62 ± 12.29 at the final follow-up. CONCLUSIONS: Treatment of adult NMS (> 100°) with severe PO could be safe and effective with MRPCO with HFT. In order to obtain the optimum sitting balance, this could reduce the prevalence of complications and rectify the curvature and the correction of PO.

Research progress on the regulation of bone marrow stem cells by noncoding RNAs in adolescent idiopathic scoliosis.

Adolescent idiopathic scoliosis (AIS) is a common spinal deformity in young women, but its pathogenesis remains unclear. The primary pathogenic factors contributing to its development include genetics, abnormal bone metabolism, and endocrine factors. Bone marrow stem cells (BMSCs) play a crucial role in the pathogenesis of AIS by regulating its occurrence and progression. Noncoding RNAs (ncRNAs) are also involved in the pathogenesis of AIS, and their role in regulating BMSCs in patients with AIS requires further evaluation. In this review, we discuss the relevant literature regarding the osteogenic, chondrogenic, and lipogenic differentiation of BMSCs. The corresponding mechanisms of ncRNA-mediated BMSC regulation in patients with AIS, recent advancements in AIS and ncRNA research, and the importance of ncRNA translation profiling and multiomics are highlighted.

Promotion effect of FGF23 on osteopenia in congenital scoliosis through FGFr3/TNAP/OPN pathway.

BACKGROUND: Congenital scoliosis (CS) is a complex spinal malformation of unknown etiology with abnormal bone metabolism. Fibroblast growth factor 23 (FGF23), secreted by osteoblasts and osteocytes, can inhibit bone formation and mineralization. This research aims to investigate the relationship between CS and FGF23. METHODS: We collected peripheral blood from two pairs of identical twins for methylation sequencing of the target region. FGF23 mRNA levels in the peripheral blood of CS patients and age-matched controls were measured. Receiver operator characteristic (ROC) curve analyses were conducted to evaluate the specificity and sensitivity of FGF23. The expression levels of FGF23 and its downstream factors fibroblast growth factor receptor 3 (FGFr3)/tissue non-specific alkaline phosphatase (TNAP)/osteopontin (OPN) in primary osteoblasts from CS patients (CS-Ob) and controls (CT-Ob) were detected. In addition, the osteogenic abilities of FGF23-knockdown or FGF23-overexpressing Ob were examined. RESULTS: DNA methylation of the FGF23 gene in CS patients was decreased compared to that of their identical twins, accompanied by increased mRNA levels. CS patients had increased peripheral blood FGF23 mRNA levels and decreased computed tomography (CT) values compared with controls. The FGF23 mRNA levels were negatively correlated with the CT value of the spine, and ROCs of FGF23 mRNA levels showed high sensitivity and specificity for CS. Additionally, significantly increased levels of FGF23, FGFr3, OPN, impaired osteogenic mineralization and lower TNAP levels were observed in CS-Ob. Moreover, FGF23 overexpression in CT-Ob increased FGFr3 and OPN levels and decreased TNAP levels, while FGF23 knockdown induced downregulation of FGFr3 and OPN but upregulation of TNAP in CS-Ob. Mineralization of CS-Ob was rescued after FGF23 knockdown. CONCLUSIONS: Our results suggested increased peripheral blood FGF23 levels, decreased bone mineral density in CS patients, and a good predictive ability of CS by peripheral blood FGF23 levels. FGF23 may contribute to osteopenia in CS patients through FGFr3/TNAP / OPN pathway.

Inhibition of miR-182-5p Targets FGF9 to Alleviate Osteoarthritis.

Background: The pathogenesis of osteoarthritis (OA) is complex and there is no specific drug for treatment. The aim of this study was to identify the molecular targets of OA therapy, focusing on the expression and biological functions of miR-182-5p and its target genes in OA. Methods: miR-182-5p and fibroblast growth factor 9 (FGF9) were overexpressed or knocked down in IL-1ß-induced chondrocytes. An OA knee model was performed by surgically destroying the medial meniscus. The gene expression of miR-182-5p and FGF9 was calculated. The protein FGF9 was tested by western blotting. Cell counting kit-8 (CCK8), plate cloning assay, and flow cytometry were conducted to evaluate cell proliferation and apoptosis. The expression of inflammatory factors, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and interleukin (IL)-8, was evaluated using enzyme-linked immunosorbent assay (ELISA). Dual-luciferase reporter assays validated the targeting relationship between miR-182-5p and FGF9. Hematoxylin-eosin (HE) and safranin O-fast Green (S-O) staining were utilized to access cartilage damage. Ki67 expression in cartilage was detected using immunohistochemistry (IHC). TdT-mediated dUTP nick-end labeling (TUNEL) assays were used to calculate the apoptosis rate of cartilage. Results: The expression of miR-182-5p was upregulated, and FGF9 was downregulated in the IL-1ß-induced chondrocytes. OA chondrocytes proliferation ability in the miR-182-5p mimics group was decreased, and the apoptosis rate and inflammatory factor were increased. Transfection with miR-182-5p inhibitor increased the proliferative ability and decreased the apoptosis rate in the IL-1ß-induced chondrocytes. Transfection with miR-182-5p inhibitor reversed IL-1ß-induced inflammatory factor release in chondrocytes. Targeted binding sites existed between miR-182-5p and FGF9. After overexpression of FGF9, the miR-182-5p effect on OA chondrocytes was reversed. The hyaline cartilage thickness and proteoglycan content decreased in OA rats, and this was reversed by miR-182-5p inhibitor treatment. Conclusions: miR-182-5p expression levels were increased in OA chondrocytes and regulated chondrocyte proliferation, apoptosis, and inflammation by targeting FGF9. miR-182-5p is a potential gene for OA treatment.

Treatment of ankylosing spondylitis complicated with a thoracolumbar Andersson lesion by posterior closed osteotomy, debridement and fusion through the fracture line.

BACKGROUND: An Andersson lesion (AL) is a fatigue fracture occurring across three columns in ankylosing spondylitis (AS), resulting in spinal pseudarthrosis (SP) formation, most commonly in the thoracolumbar segment. However, there is still great controversy and few reports on the best surgical method for the treatment of AS combined with thoracolumbar AL. The purpose of this study was to investigate the efficacy of posterior closed osteotomy, debridement and fusion through the fracture line for the treatment of this disease. METHODS: The clinical data of 13 patients (male 8, female 5, mean age 50.6 years) with AS combined with thoracolumbar AL treated with posterior closed osteotomy, debridement and fusion through the fracture line were retrospectively analysed. The following parameters of the full-length lateral spine radiographs were measured preoperatively and at the last follow-up: cervical 7 tilt (C7T), global kyphosis (GK), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), local kyphosis (LK), angle of the fusion levels (AFL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS) and sagittal vertical axis (SVA). The visual analog scale (VAS), Oswestry disability index (ODI) and Scoliosis Research Society-22 (SRS-22) scores were recorded preoperatively and at the last follow-up. RESULTS: The mean operation time was 345 min, the mean blood loss was 673 mL, and the mean follow-up time was 21.9 months. Compared with the preoperative values, the C7T, GK, TK, TLK, LK, AFL, PT, SS and SVA values of all patients were significantly improved at the last follow-up (P < 0.05); GK improved from 81.62 ± 16.11 to 50.15 ± 8.55, with an average of 31° of correction (F = 75.945, P<0.001). The VAS, ODI and SRS-22 scores also significantly improved (P < 0.05). At the last follow-up, bone fusion was found in all fracture ends. One patient developed numbness in the lower limbs after surgery and recovered after 3 months of rehabilitation; none of the remaining patients experienced postoperative complications. CONCLUSIONS: Posterior closed osteotomy, debridement and fusion through the fracture line completely removes the necrotic tissue around the SP, relieves symptoms, and corrects kyphosis simultaneously. It reduces the tension behind the fracture line or changes the tension into compressive stress, enabling stable repair of the fracture and avoiding anterior surgery. It is a safe and effective operation.

Strategy and Efficacy of Surgery for Congenital Cervicothoracic Scoliosis with or without Hemivertebra Osteotomy.

OBJECTIVE: Cervicothoracic scoliosis will cause severe deformities in the early stage, and its structure is complex and the surgical methods are varied. The purpose of this research is to explore the indication and analyze the corrective effect of the two different posterior approach surgical strategies, including correction with fusion and hemivertebra osteotomy, for congenital cervicothoracic scoliosis deformities in children and adolescents. METHODS: This was a retrospective study of 21 patients with cervicothoracic scoliosis who received surgical treatment from January 2010 to June 2020, including nine cases of posterior hemivertebra osteotomy and fusion surgery and 12 cases of posterior correction and fusion alone. The Cobb angle, T1 tilt angle, clavicular angle, neck tilt angle, radiographic shoulder height, sagittal vertical axis, coronal balance distance, and local kyphosis angle were measured preoperatively, postoperatively, and at the last follow-up. Posterior approach hemivertebra resection or correction with fusion surgery was adopted based on the different individual characteristics of deformity such as main curve Cobb angle, growth potential, and flexibility. Patients were divided into two groups (osteotomy group and nonosteotomy group) according to whether a hemivertebra osteotomy was performed, and the corrective results in the two groups were compared. Paired-sample t tests or independent-sample t tests were used. RESULTS: The median follow-up after surgery of the 21 patients was 36 months (range, 18-72 months). The Cobb angle was corrected from 45.81° ± 14.23° preoperatively to 10.48° ± 5.56° postoperatively (correction rate, 77.78% ± 8.93%). The T1 tilt angle decreased from 15.26° ± 7.08° preoperatively to 3.33° ± 2.14° postoperatively (correction rate,73.42% ± 21.86%). The radiographic shoulder height was corrected from 1.13 ± 0.74 cm preoperatively to 0.52 ± 0.42 cm postoperatively (correction rate, 39.51% ± 35.65%). The clavicular angle improved from 2.52° ± 1.55° preoperatively to 1.16° ± 0.96° postoperatively (correction rate, 47.18% ± 35.84%). No significant differences were found at the last follow-up (p > 0.05). The Cobb angle of the main curve, T1 tilt angle, clavicular angle, cervical tilt angle, and shoulder height difference were similar in the two groups (p > 0.05). CONCLUSIONS: Posterior approach hemivertebra resection or correction with fusion surgery can be used in the treatment of congenital cervicothoracic scoliosis with satisfactory results, and the surgeon can make an individualized surgical plan according to individual characteristics of deformity.

Posterior-only debridement, bone fusion, single-segment versus short-segment instrumentation for mono-segmental lumbar or lumbosacral pyogenic vertebral osteomyelitis: minimum five year follow-up outcomes.

BACKGROUND: Pyogenic vertebral osteomyelitis (PVO), which is a potentially life-threatening condition and is associated with significant morbidity and mortality, is a cause of back pain that can lead to neurologic deficits if not diagnosed in time and effectively treated. The objective of this study is to compare the efficacy of posterior single-segment and short-segment fixation combined with one-stage posterior debridement and fusion for the treatment of mono-segmental lumbar or lumbosacral PVO. METHODS: Charts of all patients with mono-segmental lumbar or lumbosacral PVO were treated by single-stage posterior debridement, bone graft fusion, and pedicle screw fixation from April 2012 to January 2016. All patients were divided into two groups: sinlge-segment fixation (Group A, n = 31) and short-segment fixation (Group B, n = 36). These patients were followed up for a minimum of five years. The clinical efficacy was evaluated and compared on average operation time, blood loss, visual analog scale (VAS), erythrocyte sedimentation rate (ESR), C-Reactive protein (CRP), neurological function recovery and local lordotic angle. RESULTS: All 67 patients were completely cured during the follow-up. All patients had significant improvement of neurological condition and pain relief at the final follow-up. The VAS was 7.1 ± 0.7 in group A and 7.2 ± 0.6 in group B pre-operatively, which decreased to 2.1 ± 0.6 and 2.0 ± 0.7, respectively, at three months after surgery, then reduced to 0.4 ± 0.5 and 0.5 ± 0.5, respectively, at the final follow-up. ESR, CRP returned to normal limits in all patients 3 months after surgery. The mean blood loss and operation time in group A were less than that in group B (P < 0.05). The local lordotic angle in group A was increased from preoperative - 1.7 ± 7.9° to postoperative 5.8 ± 7.1°, with angle loss of 1.5 ± 0.8° at the final follow-up, respectively (P < 0.05). The local lordotic angle in group B was increased from preoperative - 1.6 ± 7.8° to postoperative 13.5 ± 6.2°, with angle loss of 1.3 ± 0.8° at the final follow-up, respectively (P < 0.05). In the mean postoperative local lordotic angle, there was significant difference between the two groups at the time of immediate postoperative period or the final follow-up (P < 0.05). CONCLUSION: Posterior-only debridement, interbody graft using titanium mesh cage, posterior single-segment instrumentation and fusion represent a safe and effective treatment option for selected patients with mono-segmental lumbar and lumbosacral PVO. This approach may preserve more lumbar normal motor units with less blood loss and operation time when compared with that of short-segment fixation. But short-segment fixation was superior to the single-segment fixation in the correction of kyphosis.

Retrospective analysis of deformed complex vertebral osteotomy in children with severe thoracic post-tubercular angular kyphosis.

BACKGROUND: Many surgical options have been described to manage post-tubercular kyphosis, but the standard approach for treating severe post-tubercular angular kyphosis in children has not been established yet. The present study was performed to evaluate the safety and efficacy of deformed complex vertebral osteotomy (DCVO) for the treatment of severe thoracic post-tubercular angular kyphosis (> 70°) in children. METHODS: Deformed complex vertebrae indicated that multiple deformed and fused vertebrae were usually involved with two or more vertebral bodies and the partial or total fusion of many segments' facet joints and intervertebral discs. Thus, DCVO indicated that a wider posterior wedge-shaped and three-column osteotomy was performed within deformed complex vertebrae to correct a more extensive range of angles. From 2010 to 2017, 15 children who suffered from severe thoracic post-tubercular angular kyphosis underwent DCVO. Deformed complex vertebrae involved two vertebral bodies in 9 patients and three vertebral bodies in 6 patients. The Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) were assessed preoperatively and at the final follow up. This was a retrospective study analysing the outcome after grade 4/5 spinal osteotomies in deformed complex vertebrae. RESULTS: The mean duration of surgery was 239 ± 37.81 min. The average period of follow-up was 31.6 ± 6.98 months. The preoperative mean kyphosis of deformed complex vertebrae was 83.39° ± 9.04°; the mean thoracic kyphosis (TK) and lumbar lordosis (LL) were 81.09° ± 8.51° and 80.51° ± 7.64°, respectively; the mean sagittal vertical axis (SVA) was 3.83 cm ± 1.43 cm. The postoperative mean kyphosis of deformed complex vertebrae was reduced to 19.98° ± 2.47° (P < 0.001) with a mean kyphosis correction of 63.41°; at the final follow up, it was 18.4° ± 2.29° (P < 0.001) without obvious loss of correction. The postoperative mean TK, LL, and SVA were reduced to 24.05° ± 3.84°, 46.9° ± 3.53°, and 0.6 cm ± 0.34 cm, respectively (P < 0.001 for all); and there was no obvious loss of sagittal alignment and balance at the final follow up (p = 0.982, p = 0.604, p = 0.754). Complicated with neural dysfunction preoperatively, 5 Frankel's grade D cases showed complete neurological recovery at final follow up. VAS score reduced from 3.6 ± 1.18 to 0.87 ± 0.64 (P < 0.001); and ODI score reduced from 22.21 ± 6.93 to 5.02 ± 2.6 (P < 0.001) at the final follow up. CONCLUSIONS: DCVO was an individualized osteotomy for treating severe thoracic post-tubercular angular kyphosis in children and could be safe and effective in reducing the incidence of complications and significantly improving kyphosis correction.

Preoperative Halo-Femoral Traction With Posterior Surgical Correction for the Treatment of Extremely Severe Rigid Congenital Scoliosis (Cobb Angle >120°).

INTRODUCTION: To evaluate the effectiveness and safety of preoperative halo-femoral traction (HFT) with posterior surgical correction for the treatment of extremely severe rigid congenital scoliosis (>120°). METHODS: We reviewed the records of all patients with extremely severe rigid congenital scoliosis (>120°) treated with preoperative HFT from 2010 through 2018. Radiographic measurements were performed. The period of traction, blood loss, operation time, complications, and pulmonary function test results were recorded. RESULTS: A total of 11 patients were included in the study. All patients underwent preoperative HFT with posterior surgical correction. The mean preoperative main curve Cobb angle was 127.9° ± 4.4°, and the average correction rate was 33.5% posttraction, 54.8% postoperation, and 55.3% at the latest follow-up. Pulmonary function improved significantly after traction, and forced vital capacity and forced expiratory volume in 1 second increased from 34.7% and 33.4% to 48.1% and 48.5%, respectively. Only one patient experienced halo pin infection during HFT. No patients experienced permanent neurologic deficits or death. CONCLUSION: For extremely severe rigid congenital scoliosis with a Cobb angle greater than 120°, preoperative HFT with posterior surgical correction offers an effective and safe corrective option. The perioperative complication rate can be partially reduced. STUDY DESIGN: Retrospective study.

Minimum 5-year follow-up outcomes for one-stage posterior instrumentation without neurosurgery intervention for correction of scoliosis associated with Chiari I malformation and syringomyelia.

INTRODUCTION: Traditionally, the common belief has been that, all patients with Chiari I malformation (CM-1) and syringomyelia (SM) undergoing a neurosurgical procedure even if they are neurologically asymptomatic. As the pathology of CM-1 and SM has become better understood, the traditional concepts have been challenged. The objective of this study was to investigate the minimum 5-year follow-up clinical outcomes of surgical treatment of patients with scoliosis associated with CM-1 and SM and to evaluate the necessity of neurosurgical intervention before corrective surgery. METHODS: This retrospective study was performed from May 2009 to September 2014. We enrolled 35 patients with scoliosis associated with CM-1 and SM who were undergoing spinal correction surgery without neurosurgical intervention. During the surgery, spinal cord monitor and wake-up test were used. Preoperative, postoperative, and final follow-up major curve coronary Cobb angle, correction rate, apical vertebral rotation (AVR), apical vertebral translation (AVT), thoracic kyphosis angle (T5-T12), lumbar lordosis angle (L1-S1) were analyzed on radiographs. RESULTS: The mean follow-up period was 82.5 months. The preoperative and postoperative mean curve coronary Cobb angle was from 55.7 ± 7.5° to 20.1 ± 5.8°, correction rate was 63.9%, AVR from 2.8 ± 0.6° to 1.3 ± 0.5°, AVT from 5.1 ± 1.4 to 1.7 ± 0.7 cm, thoracic kyphosis angle from 18.7 ± 4.0° to 32.2 ± 2.7°, lumbar lordosis angle from 36.3 ± 4.1° to 43.8 ± 3.2°. No neurological deficits occurred during the operation and follow-up. CONCLUSIONS: Our minimum 5-year follow-up outcomes showed that in a distinct patient population of neurologically asymptomatic individuals with CM-1, SM and progressive scoliosis, posterior instrumented spinal deformity surgery can be safely done without neurosurgical interverventions with the help of preoperative flexibility evaluation and intraoperative neuromonitoring.

Posterior-only surgical correction with heavy halo-femoral traction for the treatment of extremely severe and rigid adolescent idiopathic scoliosis (> 130°).

INTRODUCTION: The treatment of extremely severe and rigid spinal deformities was a great surgical challenge. Pulmonary impairment often occurred, which increased the challenges to already daunting surgical approaches. The present study was performed to evaluate the safety and efficacy of posterior-only surgical correction with heavy halo-femoral traction (HFT) for the treatment of extremely severe and rigid adolescent idiopathic scoliosis (AIS) of more than 130°. MATERIALS AND METHODS: From 2010 to 2017, 11 patients suffered from extremely severe and rigid AIS of more than 130° underwent posterior-only surgical correction with HFT. The preoperative mean coronal Cobb angle of major curve was 139.01° ± 5.83°, and the mean flexibility was 17.21% ± 3.33%; the mean angle of thoracic kyphosis (TK) and lumbar lordosis (LL) were 65.02° ± 7.21° and 39.05° ± 4.08°, respectively; the mean trunk shift (TS) and sagittal vertical axis (SVA) were 3.3 ± 0.97 cm and 3.97 ± 1.16 cm, respectively; moreover, the percent forced vital capacity (FVC%) and percent forced expiratory volume in 1 s (FEV1%) were 50.08% ± 6.07% and 53.46% ± 5.96%, respectively; the mean body height and weight were 140.09 ± 4.95 cm and 37 ± 4.34 kg, respectively. RESULTS: The mean duration of surgery was 335.91 ± 48.31 min and blood loss was 1590 ± 520.1 ml. The average period of follow-up was 32.18 ± 8.17 months. After heavy HFT, the mean coronal Cobb angle of major curve was reduced to 82.98° ± 6.91° with correction rate of 40.39%. After posterior-only surgical correction, the mean coronal Cobb angle was further reduced to 51.17° ± 5.4° with correction rate of 63.27%. The postoperative mean TK, LL, TS and SVA were improved to 23.85° ± 5.14°, 44.95° ± 2.26°, 1.32 ± 0.72 cm and 1.42 ± 0.83 cm, respectively. At the final follow-up, the corrective loss rate of Cobb angle was only 0.72%; moreover, the mean FVC% and FEV1% were increased to 65.45% ± 5.29% and 69.08% ± 5.32% with improvement of 15.36% and 15.62%, respectively; the mean body height and weight were increased to 154.45 ± 5.32 cm and 45 ± 4.02 kg with improvement of 14.36 cm and 8 kg, respectively. The spinal cord function was stable, and there were no new neurological symptoms after correction. CONCLUSIONS: Posterior-only surgical correction with heavy HFT could be safe and effective for the treatment of extremely severe and rigid AIS of more than 130° in reducing the incidence of complications and greatly improving curve correction.

Halo traction combined with posterior-only approach correction for cervical kyphosis with Neurofibromatosis-1: minimum 2 years follow-up.

BACKGROUND: Surgical management of cervical kyphosis in patients with NF-1 is a challenging task. Presently, anterior-only (AO), posterior-only (PO) and combined anterior-posterior (AP) spinal fusion are common surgical strategies. However, the choice of surgical strategy and application of Halo traction remain controversial. Few studies have shown and recommended posterior-only approach for cervical kyphosis correction in patients with NF-1. The aim of this study is to evaluate the safety and the effectiveness of halo Traction combined with posterior-only approach correction for treatment of cervical kyphosis with NF-1. METHODS: Twenty-six patients with severe cervical kyphosis due to NF-1 were reviewed retrospectively between January 2010 and April 2018. All the cases underwent halo traction combined with posterior instrumentation and fusion surgery. Correction result, neurologic status and complications were analyzed. RESULTS: In this study, cervical kyphosis Cobb angle decreased from initial 61.3 ± 19.7 degrees to postoperative 10.6 ± 3.7 degrees (P<0.01), with total correction rate of 82.7%, which consist of 45.8% from halo traction and 36.9% from surgical correction. JOA scores were improved from preoperative 13.3 ± 1.6 to postoperative 16.2 ± 0.7 (P<0.01). Neurological status was also improved. There was no correction loss and the neurological status was stable in mean 43 months follow-up. Three patients experienced minor complications and one patient underwent a second surgery. CONCLUSION: Halo traction combined with PO approach surgery is safe and effective method for cervical kyphosis correction in patients with NF-1. A satisfied correction result, and successful bone fusion can be achieved via this procedure, even improvement of neurological deficits can also be obtained. Our study suggested that halo traction combined with PO approach surgery is another consideration for cervical kyphosis correction in patients with NF-1.

Posterior-only debridement, internal fixation, and interbody fusion using titanium mesh in the surgical treatment of thoracolumbar tuberculosis with spinal epidural abscess: a minimum 5-year follow-up.

OBJECTIVE: To investigate the clinical efficacy and feasibility of posterior-only debridement, internal fixation, and interbody fusion using titanium mesh in the surgical treatment of thoracolumbar tuberculosis (TB) with spinal epidural abscess. METHODS: From January 2008 to January 2014, a total of 45 patients (27 male and 18 female) were reviewed. The patients were diagnosed with thoracolumbar TB with spinal epidural abscess. The patients underwent posterior-only debridement, internal fixation, and interbody fusion using titanium mesh. Hence, we assessed the intraoperative and postoperative complications, disease recurrences, kyphosis deformity correction, and neurological improvement following the American Spinal Injury Association (ASIA). We used SPSS 22.0 for the statistical analyses. An independent Student's t-test was used for the analysis of preoperative and postoperative continuous variables. The value of P (P < 0.05) was considered statistically significant. RESULTS: The mean age of patients was 37.76 ± 10.94 years (17-59 years). The mean follow-up time was 82.76 ± 12.56 months (60-128 months). The mean kyphosis Cobb angle preoperative was 29.36 ± 13.29° (5-55°) and postoperative was 3.58 ± 5.44° (- 6-13°), given the value of P (P < 0.001). According to the neurological score by the ASIA scale, there were 3 cases of grade B, 11 cases of grade C, 16 cases of grade D, and 15 cases of grade E preoperatively. The neurological score improved by 1 ~ 2 grades. All patients achieved pain relief and the VAS score significantly reduced at the last follow-up (P<0.05). While 1 patient had cerebrospinal fluid leakage, 1 had a neurological complication, 1 had delayed surgical wound healing, and 1 had a disease recurrence. No pseudoarthrosis or implant failure occurred in our patients. All patients achieved solid bone graft fusion. CONCLUSION: For thoracolumbar TB patients with spinal epidural abscess, posterior-only debridement, internal fixation, and interbody fusion using titanium mesh are safe and effective surgical treatments.

Lower androgen levels promote abnormal cartilage development in female patients with adolescent idiopathic scoliosis.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a disease characterized by changes in the three-dimensional structure of the spine. Studies have shown that the development of AIS might be associated with genetic, biomechanics, endocrine factors and abnormal bone or cartilage development. METHODS: Blood samples collected from 301 female patients (161 females with AIS and 140 females without AIS) were used for genotyping. Forty-eight serum samples from 161 females with AIS and 40 serum samples from 140 females without AIS were subjected to enzyme-linked immunosorbent assays (ELISAs). We also evaluated 32 facet joints (18 females with AIS and 14 females without AIS from the 301 female patients) using immunohistochemistry, Western blotting, and isolation of human primary chondrocytes, among other methods. We treated the AIS primary chondrocytes with dihydrotestosterone (DHT) to verify the relationship among androgen, the androgen receptor (AR), and its downstream pathway proteins. RESULTS: The serum androgen level in the AIS group was significantly decreased (1.94±0.09 vs. 2.284±0.103) compared with that in the non-AIS (control) group. The single nucleotide polymorphism genotyping results showed that the mutation rates of rs6259 between the AIS and control groups were significantly different (G/G genotype: 48.4% vs. 42.1%, G/A genotype: 40.4% vs. 35.7%, P<0.05). The levels of interleukin (IL)-6 and metalloproteinase (MMP)-13 were increased in the cartilage of AIS patients, and these patients also exhibited decreased AR levels. The cell experiment results showed that androgen reduced the degree of abnormal cartilage development in female AIS patients through the AR/IL-6/signal transducer and activator of transcription 3 (STAT3) signaling pathway. CONCLUSIONS: Our study provides a new perspective on the pathogenesis of AIS and indicates that decreased androgen levels in female AIS patients play a potential role in the development of AIS via the AR/IL-6/STAT3 signaling pathway.

Band-edge mediated frequency down-conversion in a gas-filled anti-resonant hollow-core fiber.

We demonstrate frequency down-conversions of femtosecond pulses through dispersive wave generation and degenerate four-wave mixing in a gas-filled anti-resonant hollow-core fiber. These are achieved by exploiting the rapid variation of the dispersion in the fiber's transmission band edge. In this approach, the wavelength of the down-shifted radiation is governed solely by the thickness of the dielectric wall at the core-cladding interface, while other system parameters are accountable only for inducing sufficient nonlinear phase shifts. With the right choice of cladding wall thickness, the concept can be applied directly for generating high-power mid-infrared femtosecond pulses.

Analyzing mode index mismatch and field overlap for light guidance in negative-curvature fibers.

We numerically investigate the role of cladding geometries in two widely used anti-resonant hollow-core fiber designs with negative curvatures, the tubular negative-curvature fiber and ice-cream-cone negative-curvature fiber. The confinement loss governed by the inhibited coupling between the modes in the core and cladding is thoroughly examined systematically against the core-cladding curvature for both types. We show that, in addition to the mode-index mismatch, the mode-field overlap also plays a key role in determining the loss. Simultaneously, we find the ice-cream-cone negative-curvature fiber can exhibit better loss performance than the tubular design within a specific range of the curvature. This enhancement is achieved without sacrificing the transmission bandwidth and is relatively robust against the fabrication error.

High methylation of lysine acetyltransferase 6B is associated with the Cobb angle in patients with congenital scoliosis.

BACKGROUND: The etiology of congenital scoliosis (CS) is complex and uncertain. Abnormal DNA methylation affects the growth and development of spinal development. In this study, we investigated the role of DNA methylation in CS. METHODS: The target region DNA methylation level in the peripheral blood of patients with CS was analyzed. Through in-depth analysis, genes closely related to the growth and development of the vertebra were identified. EdU staining was performed to verify the role of differentially expressed genes in chondrocyte proliferation. RESULTS: The hypermethylated KAT6B gene was observed in patients with CS, and was positively correlated with the Cobb angle. KAT6B was primarily expressed on chondrocytes. The promoter of KAT6B in CS patients was hypermethylated, and its expression was significantly reduced. Further mechanistic studies revealed that EZH2 mediated trimethylation of lysine 27 on histone H3 of the KAT6B promoter. Overexpression of KAT6B in CS-derived primary chondrocytes can significantly promote chondrocyte proliferation, which may be related to activation of the RUNX2/Wnt/ß-catenin signaling pathway. CONCLUSION: Epigenetic modification of KAT6B may be a cause of CS. If similar epigenetic modification abnormalities can be detected through maternal liquid biopsy screening, they may provide useful biomarkers for early screening and diagnosis of CS.

rs6127698 polymorphism in the MC3R gene and susceptibility to multifocal tuberculosis in southern Chinese Han population.

OBJECTIVE: To investigate the relationship between melanocortin-3 receptor (MC3R) gene polymorphism and tuberculosis (TB) susceptibility in Han population in southern China. METHODS: A total of 341 patients with TB (173 with pulmonary TB and 168 with multifocal TB) and 359 healthy controls were enrolled. Genotyping was performed by PCR and DNA sequencing, and detection of protein was performed by western blot. RESULTS: The distributions of genotype and allele frequencies of rs6127698 differed significantly between the pulmonary and multifocal TB groups, and between the multifocal TB and control groups. The GG genotype was significantly more common among multifocal TB patients than among pulmonary TB patients (P = .009) and those in the control group (P = .001) under the recessive model. GG+GT genotype was more common in multifocal TB than in pulmonary TB (P < .01) and control group (P < .01) under the dominant model. G allele was more common in multifocal TB than in pulmonary TB (P < .0167) and control group (P < .0167). Patients with multifocal TB had an increased expression of MC3R protein than healthy controls (P < .05). CONCLUSIONS: In the southern Chinese Han population, the MC3R rs6127698 polymorphism, which accompanying an increased expression of MC3R protein,was associated with susceptibility to multifocal TB. Presence of the G allele increased the risk of developing multifocal TB.

Posterior-Only Surgical Correction with Heavy Halo-Femoral Traction for the Treatment of Severe and Rigid Congenital Scoliosis Associated with Tethered Spinal Cord and Type II Split Cord Malformation.

OBJECTIVE: To evaluate the safety and efficacy of posterior-only surgical correction with heavy halo-femoral traction for the treatment of severe and rigid congenital scoliosis (SRCS) associated with tethered spinal cord (TSC) and type II split cord malformation (SCM). METHODS: Thirteen patients with SRCS associated with TSC and type II SCM underwent posterior-only surgical correction with heavy halo-femoral traction. The preoperative mean coronal Cobb angle was 88.87° ± 12.15°; the mean flexibility was 15.28% ± 3.88%; and the mean angle of thoracic kyphosis and lumbar lordosis was 39.63° ± 18.47° and 56.99° ± 10.02°, respectively. RESULTS: The mean duration of surgery was 320 ± 43.64 minutes and the mean blood loss was 1422.31 ± 457.59 mL. The mean follow-up period was 24.46 ± 7.53 months. After heavy halo-femoral traction, the mean coronal Cobb angle was reduced to 59.14° ± 8.75°. After posterior-only surgical correction, postoperative mean coronal Cobb angle was further reduced to 33.85° ± 8.77°. The postoperative mean correction rate was 62.46% ± 5.04%. The postoperative mean angle of thoracic kyphosis and lumbar lordosis was 29.31° ± 6.75° and 47.79° ± 3.68°, respectively. At the final follow-up, the corrective loss rate of Cobb angle was only 0.69%. There were no significant differences between final follow-up and preoperative modified Japanese Orthopaedic Association total scores. The Scoliosis Research Society-22 total score improved at the final follow-up evaluation compared with the preoperative total score. CONCLUSIONS: Without prophylactic neurosurgical intervention and spine-shortening osteotomy, posterior-only surgical correction with heavy halo-femoral traction could be safe and effective for the treatment of SRCS associated with TSC and type II SCM.