Objective:To evaluate the characteristic manifestations of lumbar fusion following oblique lateral interbody fusion (OLIF), determine the specific incidence of these patterns, and the identify factors associated with fusion characteristics.Methods:This retrospective study analyzed 209 patients who underwent OLIF surgery at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, between July 2017 and September 2023. The cohort had a mean age of 64.2±9.8 years and included 125 males and 84 females. A total of 338 lumbar segments were assessed, comprising 159 segments treated with stand-alone OLIF (OLIF-SA) and 179 segments treated with OLIF combined with posterior pedicle screw fixation (OLIF-PSF). Inclusion criteria were: patients aged 18-80 years who underwent OLIF with complete radiographic records. Surgical parameters, including fixation method, number of fused segments, surgical approach, and cage dimensions (height and width), were obtained from operative records. Radiographic evaluation included preoperative osteophytes, Hounsfield unit (HU) values of endplates, and cage positioning. Fusion rate, fusion pattern (lateral vs. central), cage subsidence, and related influencing factors were assessed. Clinical outcomes were measured via the Oswestry disability index (ODI) and visual analog scale (VAS) preoperatively, immediately postoperatively, and at 1-year follow-up. Results:The overall fusion rate was 98.2% (332/338), with a non-union rate of 1.8% (6/338). The incidence of lateral fusion was 40.2% (136/338). In the OLIF-SA group, lateral and central fusion rates were 50.3% (80/159) and 49.7% (79/159), respectively, with no cases of non-union. In the OLIF-PSF group, lateral fusion occurred in 31.3% (56/179), central fusion in 65.4% (117/179), and non-union in 3.3% (6/179), with statistically significant differences between groups ( P<0.05). Preoperative osteophytes and higher endplate HU values were significantly associated with lateral fusion ( P<0.05). However, cage dimensions and cage position (anterior-posterior and lateral placement) were not significantly associated with fusion pattern ( P>0.05). Overall, 61.5% (208/338) of segments showed no cage subsidence; 24.5% (83/338) had settling, and 14.0% (47/338) had grade 1 or higher subsidence. Among lateral fusion cases, the rates of no subsidence, anchoring, grade 1, grade 2, and grade 3 subsidence were 67.6%, 21.3%, 7.4%, 3.9%, and 0.7%, respectively. In the central fusion group, these rates were 59.2%, 27.6%, 9.2%, 2.5%, and 1.3%, respectively. In the non-union group, grade 2 and 3 subsidence occurred in 50% (3/6) each, significantly higher than in the other fusion groups ( P<0.05). Post hoc analysis confirmed that grade 2 and 3 subsidence rates were significantly elevated in the non-union group compared to the lateral and central fusion groups, while other subsidence categories showed no significant differences across groups. Clinically, patients showed significant improvements in ODI and VAS scores following surgery ( P<0.05). Conclusions:Lateral fusion occurred in 40.2% of OLIF cases. The OLIF-SA technique, preoperative osteophytes, and elevated preoperative HU values were significantly associated with lateral fusion. In contrast, surgical approach, number of fused segments, cage height, width, and cage positioning did not significantly influence the occurrence of lateral fusion.

Objective:This study aimed to explore the molecular mechanisms of the maladaptation of H3N2 influenza virus in chicken embryos, provide a theoretical basis for the restoration of H3N2 influenza vaccine production in chicken embryos.Methods:Samples of respiratory secretions from patients with influenza-like symptoms (Influenza-like Illness, ILI) caused by H3N2 influenza virus were inoculated into chicken embryos and Madin-Darby Canine Kidney cells (MDCK), respectively. After isolating the virus, hemagglutination experiments were conducted to detect hemagglutination titers and hemagglutination inhibition experiments were used to compare antigenic differences; further, whole-genome sequencing of H3N2 influenza virus was performed using second-generation high-throughput gene sequencing (Next Generation High-Throughput Gene Sequencing, NGS), and key amino acid sites of mutations were identified through sequence alignment; combined with sialic acid receptor binding experiments, the differences in the binding of wild-type and mutant receptor binding sites (RBS) to sialic acid receptors were compared; finally, molecular docking and molecular dynamics simulation method were used to explore the specific molecular mechanisms of how mutation sites affect the differences in the affinity of the RBS pocket for sialic acid receptors.Results:The hemagglutination assay result indicated that both chicken embryos and MDCK cells could isolate the influenza virus, and the hemagglutination inhibition test showed that no antigenic differences were produced in the isolated strains. NGS analysis revealed that the H3N2 virus underwent an F195Y mutation in the (RBS) region of the hemagglutinin (HA) protein after adaptation through chicken embryo passages. Receptor-binding experiments demonstrated that the F195Y mutation enhanced the virus′s binding ability to α2, 3-linked sialic acid glycan (Neu5Acα2-3Galβ1-4GlcNAcβ-PAA, 3′SLN), while the mutation did not affect the affinity of the RBS pocket for α2, 6-linked sialic acid glycan (Neu5Acα2-6Galβ1-4GlcNAcβ-PAA, 6′SLN). Molecular docking and molecular dynamics simulation result indicate that the F195Y mutation, by replacing a hydrophobic amino acid with a hydrophilic one, leads to a significant decrease in the structure of the RBS pocket, enhancing the binding stability of the H3N2 influenza virus with α2, 3-sln. This is specifically manifested by an increase in binding time and an increase in the number of hydrogen bonds at the RBS site with the receptor. Furthermore, the F195Y mutation does not alter the binding of the virus to other receptors.Conclusions:The F195Y mutation in the RBS pocket of H3N2 influenza virus is a key site affecting the viral chicken embryo inadaptability.

Objective:To evaluate the characteristic manifestations of lumbar fusion following oblique lateral interbody fusion (OLIF), determine the specific incidence of these patterns, and the identify factors associated with fusion characteristics.Methods:This retrospective study analyzed 209 patients who underwent OLIF surgery at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, between July 2017 and September 2023. The cohort had a mean age of 64.2±9.8 years and included 125 males and 84 females. A total of 338 lumbar segments were assessed, comprising 159 segments treated with stand-alone OLIF (OLIF-SA) and 179 segments treated with OLIF combined with posterior pedicle screw fixation (OLIF-PSF). Inclusion criteria were: patients aged 18-80 years who underwent OLIF with complete radiographic records. Surgical parameters, including fixation method, number of fused segments, surgical approach, and cage dimensions (height and width), were obtained from operative records. Radiographic evaluation included preoperative osteophytes, Hounsfield unit (HU) values of endplates, and cage positioning. Fusion rate, fusion pattern (lateral vs. central), cage subsidence, and related influencing factors were assessed. Clinical outcomes were measured via the Oswestry disability index (ODI) and visual analog scale (VAS) preoperatively, immediately postoperatively, and at 1-year follow-up. Results:The overall fusion rate was 98.2% (332/338), with a non-union rate of 1.8% (6/338). The incidence of lateral fusion was 40.2% (136/338). In the OLIF-SA group, lateral and central fusion rates were 50.3% (80/159) and 49.7% (79/159), respectively, with no cases of non-union. In the OLIF-PSF group, lateral fusion occurred in 31.3% (56/179), central fusion in 65.4% (117/179), and non-union in 3.3% (6/179), with statistically significant differences between groups ( P<0.05). Preoperative osteophytes and higher endplate HU values were significantly associated with lateral fusion ( P<0.05). However, cage dimensions and cage position (anterior-posterior and lateral placement) were not significantly associated with fusion pattern ( P>0.05). Overall, 61.5% (208/338) of segments showed no cage subsidence; 24.5% (83/338) had settling, and 14.0% (47/338) had grade 1 or higher subsidence. Among lateral fusion cases, the rates of no subsidence, anchoring, grade 1, grade 2, and grade 3 subsidence were 67.6%, 21.3%, 7.4%, 3.9%, and 0.7%, respectively. In the central fusion group, these rates were 59.2%, 27.6%, 9.2%, 2.5%, and 1.3%, respectively. In the non-union group, grade 2 and 3 subsidence occurred in 50% (3/6) each, significantly higher than in the other fusion groups ( P<0.05). Post hoc analysis confirmed that grade 2 and 3 subsidence rates were significantly elevated in the non-union group compared to the lateral and central fusion groups, while other subsidence categories showed no significant differences across groups. Clinically, patients showed significant improvements in ODI and VAS scores following surgery ( P<0.05). Conclusions:Lateral fusion occurred in 40.2% of OLIF cases. The OLIF-SA technique, preoperative osteophytes, and elevated preoperative HU values were significantly associated with lateral fusion. In contrast, surgical approach, number of fused segments, cage height, width, and cage positioning did not significantly influence the occurrence of lateral fusion.

Objective:This study aimed to explore the molecular mechanisms of the maladaptation of H3N2 influenza virus in chicken embryos, provide a theoretical basis for the restoration of H3N2 influenza vaccine production in chicken embryos.Methods:Samples of respiratory secretions from patients with influenza-like symptoms (Influenza-like Illness, ILI) caused by H3N2 influenza virus were inoculated into chicken embryos and Madin-Darby Canine Kidney cells (MDCK), respectively. After isolating the virus, hemagglutination experiments were conducted to detect hemagglutination titers and hemagglutination inhibition experiments were used to compare antigenic differences; further, whole-genome sequencing of H3N2 influenza virus was performed using second-generation high-throughput gene sequencing (Next Generation High-Throughput Gene Sequencing, NGS), and key amino acid sites of mutations were identified through sequence alignment; combined with sialic acid receptor binding experiments, the differences in the binding of wild-type and mutant receptor binding sites (RBS) to sialic acid receptors were compared; finally, molecular docking and molecular dynamics simulation method were used to explore the specific molecular mechanisms of how mutation sites affect the differences in the affinity of the RBS pocket for sialic acid receptors.Results:The hemagglutination assay result indicated that both chicken embryos and MDCK cells could isolate the influenza virus, and the hemagglutination inhibition test showed that no antigenic differences were produced in the isolated strains. NGS analysis revealed that the H3N2 virus underwent an F195Y mutation in the (RBS) region of the hemagglutinin (HA) protein after adaptation through chicken embryo passages. Receptor-binding experiments demonstrated that the F195Y mutation enhanced the virus′s binding ability to α2, 3-linked sialic acid glycan (Neu5Acα2-3Galβ1-4GlcNAcβ-PAA, 3′SLN), while the mutation did not affect the affinity of the RBS pocket for α2, 6-linked sialic acid glycan (Neu5Acα2-6Galβ1-4GlcNAcβ-PAA, 6′SLN). Molecular docking and molecular dynamics simulation result indicate that the F195Y mutation, by replacing a hydrophobic amino acid with a hydrophilic one, leads to a significant decrease in the structure of the RBS pocket, enhancing the binding stability of the H3N2 influenza virus with α2, 3-sln. This is specifically manifested by an increase in binding time and an increase in the number of hydrogen bonds at the RBS site with the receptor. Furthermore, the F195Y mutation does not alter the binding of the virus to other receptors.Conclusions:The F195Y mutation in the RBS pocket of H3N2 influenza virus is a key site affecting the viral chicken embryo inadaptability.

The acute combination fractures of the atlas and axis in adults have a higher rate of neurological injury and early death compared with atlas or axial fractures alone. Currently, the diagnosis and treatment choices of acute combination fractures of the atlas and axis in adults are controversial because of the lack of standards for implementation. Non-operative treatments have a high incidence of bone nonunion and complications, while surgeries may easily lead to the injury of the vertebral artery, spinal cord and nerve root. At present, there are no evidence-based Chinese guidelines for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults. To provide orthopedic surgeons with the most up-to-date and effective information in treating acute combination fractures of the atlas and axis in adults, the Spinal Trauma Group of Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field of spinal trauma to develop the Evidence-based guideline for clinical diagnosis and treatment of acute combination fractures of the atlas and axis in adults ( version 2023) by referring to the "Management of acute combination fractures of the atlas and axis in adults" published by American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) in 2013 and the relevant Chinese and English literatures. Ten recommendations were made concerning the radiological diagnosis, stability judgment, treatment rules, treatment options and complications based on medical evidence, aiming to provide a reference for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults.

Objective:To observe the diagnostic value of the fat deposition between the base of spinous process and dura mater in the mid-sagittal T1WI image of lumbar spine MRI for occult pars interarticularis defect, and to discuss the its mechanism.Methods:From January 2015 to December 2019, 32 cases with low back and leg pain were confirmed by MR scanning that the fat deposition between the dura mater and the base of spinous process with or without fat deposition in the rest of the spinal canal, including 20 males and 12 females were included. The age was 28.5±6.2 years (range, 18-57 years). Spiral CT scanning and multiplanar reconstruction were used to judge the integrity of the isthmus, levels of defect, and unilateral or bilateral defect. The observation of the above imaging data were independently completed by two orthopaedic doctors.Results:In 32 patients with epidural fat deposition, there were 24 patients with occult isthmus and 8 patients with simple epidural lipomatosis, confirmed by spiral CT multiplanar reconstruction. In 24 cases of isthmus, there were 18 males and 6 females. The age was 27.3±5.3 years (range, 18-45 years). There were 2 cases between the base of L 4 spinous process and dura mater, and 22 cases between the base of L 5 spinous process and dura mater, without fat deposition in the rest of the spinal canal. All 24 cases were bilateral isthmus, and the anterior and lateral X-ray could not be diagnosed. All patients complained of different degrees of mechanical low back pain. 6 cases with disc herniation, and no case with intermittent claudication. In 8 patients with simple epidural lipomatosis, there were 2 males and 6 females. The age ranged from 32 to 55 years, with an average of 38.4±6.7 years. There were 4 cases between the base of L 3 spinous process and dura mater, 3 cases between the base of L 4 spinous process and dura mater, and 1 case between the base of L 5 spinous process and dura mater. All 8 patients had fat deposition between the lamina and dura mater in the upper and/or the same level, and the dura mater was compressed by the fat. 8 patients complained of different degrees of low back pain without tenderness. 2 cases with disc herniation, and one case with intermittent claudication. Conclusion:The fat deposition sign between the base of spinous process and dura mater has certain specificity for occult lumbar spondylolysis. As an effective supplement to the discontinuous bone signal of spondylolysis, it is helpful to the early diagnosis of spondylolysis.

Objective:To analyze the incidence and epidemiological characteristics of traumatic spinal cord injury in China in 2018.Methods:Multi-stage stratified cluster sampling was used to randomly select hospitals capable of treating patients with spinal cord injury from 3 regions，9 provinces and 27 cities in China to retrospectively investigate eligible patients with traumatic spinal cord injury admitted in 2018. National and regional incidence rates were calculated. The data of cause of injury，injury level，severity of injury，segment and type of fracture，complications，death and other data were collected by medical record questionnaire，and analyzed according to geographical region，age and gender.Results:Medical records of 4，134 patients were included in this study，with a male-to-female ratio of 2.99∶1. The incidence of traumatic spinal cord injury in China in 2018 was 50.484 / 1 million （95% CI 50.122-50.846）. The highest incidence in the Eastern region was 53.791 / 1 million （95% CI 53.217-54.365）. In the whole country，the main causes of injury were high falls （29.58%），as well as in the Western region （40.68%），while the main causes of injury in the Eastern and Central regions were traffic injuries （31.22%，30.10%）. The main injury level was cervical spinal cord in the whole country （64.49%），and the proportion of cervical spinal cord injury in the Central region was the highest （74.68%），and the proportion of lumbosacral spinal cord injury in the Western region was the highest （32.30%）. The highest proportion of degree of injury was incomplete quadriplegia （55.20%），and the distribution pattern was the same in each region. A total of 65.87% of the patients were complicated with fracture or dislocation，77.95% in the Western region and only 54.77% in the Central region. In the whole country，the head was the main combined injury （37.87%），as well as in the Eastern and Central regions，while the proportion of chest combined injury in the Western region was the highest （38.57%）. A total of 32.90% of the patients were complicated with respiratory complications. There were 23 patients （0.56%） died in hospital，of which 17（73.91%） died of respiratory dysfunction. Conclusions:The Eastern region of China has a high incidence of traumatic spinal cord injury. Other epidemiological features include high fall as the main cause of injury cervical spinal cord injury as the main injury level，incomplete quadriplegia as the main degree of injury，head as the main combined injury，and respiratory complications as the main complication.

Circular RNA (circRNA) is a kind of RNA with a circular structure. The unique structure of circRNA endows it with various cell biological functions and characteristics. It has become a research hotspot recently. CircRNA can play a role via mechanisms, such as microRNA (miRNA) sponge, RNA binding protein, peptide translation and regulation of gene transcription. CircRNA was found to be associated with disc degeneration, spinal cord injury, scoliosis, and facet arthritis. Some techniques, including bioinformatics and molecular biology techniques, microarray and high-throughput sequencing, can be used to predict and to discover disease-related circRNA, aiming to evaluate whether circRNA can be used as a molecular biomarker for spinal and spinal cord diseases. Based on the current role of circRNA, the corresponding therapeutic strategies have been carried out in experimental animals, which can provide theoretical basis for gene therapy. At present, the researches in circRNA for spinal and spinal cord diseases are still insufficient compared with those in other fields. Currently, the main direction focuses on the miRNA sponge mechanism of circRNA. Due to the variety of diseases in spinal surgery, the research progress of circRNA is also varied. In addition, the development of microarray and high-throughput sequencing technology have greatly promoted the researches in circRNA. The availability of public database is of great significance in the study. The present review summarized the current researches status of circRNA in spinal and spinal cord diseases, aiming to deepen understanding of circRNA in spinal and spinal cord diseases.

Objective To investigate the causes of re-fractures of non fracture vertebral body after percutaneous kyphoplasty (PKP).Methods 512 patients (618 vertebral bodies) treated with PKP because of osteoporosis VCFs were recruited from June 2010 to June 2014.There were 107 males (121 vertebral bodies) and 405 females (497 vertebral bodies) with the mean age of 70.38±7.59 years old (51 to 91 years).There were 406 single segment fracture and 106 double segment fractures cases,and the fracture segments were T4 to L5.The T value of the patients' bone mineral density (BMD) was from-1.0 to-5.2 SD.The clinic characteristics of all the patients including age,sex,body weight,body height,body mass index (BMI),BMD score of the spine,volume of bone cement,restoration rate of anterior/middle vertebral height,postoperative complications (pulmonary embolism,bone cement leakage,nerve injury),and treated vertebral level were analyzed.Results 52 patients (10.16％,52/512) experienced refractures of non fracture vertebral body after kyphoplasty,and 4 experienced re-fracture of the fracture vertebral body after kyphoplasty.The average age of the 52 patients was 71.88±7.74 years old,meanwhile,the ratio of female was 94.23％ (49/52),the mean T value of BMD-4.03±0.60 SD,the ratio of initial double segment fractures 51.92％ (27/52).In addition,among the 456 cases with no fracture,the average age was 70.21±7.56 years,the ratio of female was 77.19％ (352/456);the mean T value of BMD was-2.89±0.55 SD;the ratio of initial double segment fractures was 17.32％(79/456).The data above (age,T value of BMD and initial double segment fractures) were all with statistical significant differences.Whereas the BMI,volume of bone cement,intervertebral disc leakage and restoration rate of anterior/middle vertebral height had no significant difference between the two groups.Furthermore,in the re-fracture of non fracture vertebral body group,32 cases (61.54％,32/52) were nonadjacent fractures,and 20 (38.46％,20/52) were adjacent fractures.Conclusion Osteoporosis degree,female and initial double segment fractures were major risk factors in the development of re-fracture of non fracture vertebral body after PKP.

Objective To compare the clinical outcomes between proximal femoral nail antirotation (PFNA) combined with salmon calcitonin and PFNA only for the treatment of unstable intertrochanteric fractures in elderly patients.Methods From January 2009 to December 2011,120 elderly patients with intertrochanteric fracture were randomly divided into two groups:calcitonin group and control group.Patients in calcitonin group were treated with PFNA combined with salmon calcitonin,while patients in control group were treated with PFNA only.According to Evans-Jensen classification,60 patients in calcitonin group (28 males and 32 females,with an average age of 75.1 years) were divided into 20 cases of type Ⅱ A,32 cases of type Ⅱ B and 8 type Ⅲ.Sixty patients in control group (27 males and 33 females,with an average age of 74.9 years) were divided into 22 cases of type Ⅱ A,32 cases of type Ⅱ B and 6 type Ⅲ.Bone healing was assessed with X-ray and bone mineral density (BMD) was measured by dual energy X-ray absorptiometry.Harris hip and SF-12 score,complications,adverse effect of salmon calcitonin and subsequent fragility fractures were evaluated postoperatively.Results One-hundred and thirteen patients were followed up for at least 2 years.In 6 months after surgery,there were 4 cases of delayed healing in control group.However,all fractures were healed in 12 months after surgery.No significant difference was found between the two groups in BMD preoperatively.The changes in BMD were significantly different between the two groups in 6 months,1 year and 2 years after surgery.No significant difference was found between the two groups in Harris hip and 1-year SF-12 score while the 2-year SF-12 score was significantly different between the two groups.There was 1 patient in calcitonin group who suffered from subsequent fragility fracture in 3 months after surgery,while there was 6 patients in control group during 13 to 23 months postoperatively.Conclusion PFNA combined with salmon calcitonin achieves good effect for the treatment of unstable intertrochanteric fractures in elderly patients.