Analysis of risk factors affecting postoperative neurological recovery in patients with cervical spine fracture in ankylosing spondylitis.

Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease that mainly affects the spine and involves the sacroiliac and peripheral joints. Low-energy trauma can often lead to spinal fractures and spinal cord injuries (SCIs), the treatment of AS is challenging. The prognosis of neurological function in patients with AS cervical fracture and SCI is a major problem that must sought clinician attention on urgent basis. A total of 106 patients with AS cervical fractures who underwent surgical treatment at Shanghai Changzheng Hospital between August 2009 and 2021 were included in this study. All the patients were divided into 2 groups (improved group and the control group) based on their neurological function improvement at 1 year mark after the surgery. The baseline characteristics, perioperative factors, and procedural outcomes of all the patients including injury type, AS drug treatment, the injured segment, ossified anterior longitudinal ligament injury, spinal hypersignal, decompression time window, operation duration, blood loss, preoperative and postoperative American Spinal Injury Association (ASIA) score were recorded and analyzed. Among the 106 patients, 79 demonstrated improved neurological function at 1 year mark after the surgery. Binary univariate logistic regression analysis revealed significant differences in injury type (P = .018), ossified anterior longitudinal ligament injury (P = .01), operation duration (P = .002), spinal hypersignal (P = .001), preoperative ASIA score (P < .001), and prior AS drug treatment (P = .012). No significant differences were observed in the other variables (P > .05). Binary multivariate logistic regression analysis identified spinal hypersignal (OR = 37.185, P = .028), preoperative ASIA score (OR = 0.16, P = .012) and previous AS drug treatment (OR = 0.296, P = .049) as factors associated with postoperative neurological function improvement. The preoperative ASIA score and previous drug treatment of AS were identified as protective factors affecting the improvement of neurological functions in patients with AS cervical fracture after surgery. Preoperative T2-weighted spinal hypersignal was identified as an independent risk factor affecting the improvement of neurological function recovery in patients with AS cervical fracture after the surgery.

Hounsfield units in assessing bone mineral density in ankylosing spondylitis patients with cervical fracture-dislocation.

BACKGROUND: Cervical spine fracture-dislocations in patients with ankylosing spondylitis (AS) are mostly unstable and require surgery. However, osteoporosis, one of the comorbidities for AS, could lead to detrimental prognoses. There are few accurate assessments of bone mineral density in AS patients. AIM: To analyze Hounsfield units (HUs) for assessing bone mineral density in AS patients with cervical fracture-dislocation. METHODS: The HUs from C2 to C7 of 51 patients obtained from computed tomography (CT) scans and three-dimensional reconstruction of the cervical spine were independently assessed by two trained spinal surgeons and statistically analyzed. Inter-reader reliability and agreement were assessed by interclass correlation coefficient. RESULTS: The HUs decreased gradually from C2 to C7. The mean values of the left and right levels were significantly higher than those in the middle. Among the 51 patients, 25 patients (49.02%) may be diagnosed with osteoporosis, and 16 patients (31.37%) may be diagnosed with osteopenia. CONCLUSION: The HUs obtained by cervical spine CT are feasible for assessing bone mineral density with excellent agreement in AS patients with cervical fracture-dislocation.

Posterior Release, Reduction, and Intra-Articular Fusion for Irreducible Type III Atlantoaxial Rotary Fixation.

BACKGROUND AND OBJECTIVES: For irreducible atlantoaxial rotary fixation (AARF), anterior or posterior release was often needed before posterior reduction and fusion. Anterior atlantoaxial joint release has potential complications such as retropharyngeal abscess, persistent hoarseness, and infection. This study aims to assess the efficacy of posterior release, reduction, and intra-articular fusion without resecting the C2 nerve root on irreducible type III AARF. METHODS: The data of 9 pediatric patients diagnosed with AARF who underwent posterior atlantoaxial release, reduction, and intra-articular fusion without resecting the C2 nerve root were retrospectively reviewed. Japanese Orthopaedic Association scores and Visual Analog Scale for Neck Pain were used to assess outcomes. The preoperative and follow-up assessments of atlantodens interval (ADI) were documented to evaluate the reduction of atlantoaxial joint. The patient demographics, surgery time, blood loss, bone fusion time, follow-up period, and surgery-related complications were meticulously documented. RESULTS: The mean follow-up duration was 35.1 ± 11.5 months. Complete reduction was achieved in 8 patients, while one patient did not achieve complete reduction. The ADI decreased significantly from 8.7 ± 2.2 mm before surgery to 2.1 ± 1.3 mm at the final follow-up. All patients demonstrated successful bone fusion, with an average fusion period of 3.7 ± 1.3 months. The Visual Analog Scale for Neck Pain at the final follow-up exhibited a significant decrease compared with preoperative values (P < .05), while no significant difference was observed in Japanese Orthopaedic Association scores. There were no complications related to surgery. CONCLUSION: Posterior atlantoaxial release, reduction, and intra-articular fusion with a C2 nerve root preservation technique is effective in the treatment of irreducible type III AARF.

Identification and Verification of Novel Biomarkers Involving Rheumatoid Arthritis with Multimachine Learning Algorithms: An In Silicon and In Vivo Study.

Background: Rheumatoid arthritis (RA) remains one of the most prevalent chronic joint diseases. However, due to the heterogeneity among RA patients, there are still no robust diagnostic and therapeutic biomarkers for the diagnosis and treatment of RA. Methods: We retrieved RA-related and pan-cancer information datasets from the Gene Expression Omnibus and The Cancer Genome Atlas databases, respectively. Six gene expression profiles and corresponding clinical information of GSE12021, GSE29746, GSE55235, GSE55457, GSE77298, and GSE89408 were adopted to perform differential expression gene analysis, enrichment, and immune component difference analyses of RA. Four machine learning algorithms, including LASSO, RF, XGBoost, and SVM, were used to identify RA-related biomarkers. Unsupervised cluster analysis was also used to decipher the heterogeneity of RA. A four-signature-based nomogram was constructed and verified to specifically diagnose RA and osteoarthritis (OA) from normal tissues. Consequently, RA-HFLS cell was utilized to investigate the biological role of CRTAM in RA. In addition, comparisons of diagnostic efficacy and biological roles among CRTAM and other classic biomarkers of RA were also performed. Results: Immune and stromal components were highly enriched in RA. Chemokine- and Th cell-related signatures were significantly activated in RA tissues. Four promising and novel biomarkers, including CRTAM, PTTG1IP, ITGB2, and MMP13, were identified and verified, which could be treated as novel treatment and diagnostic targets for RA. Nomograms based on the four signatures might aid in distinguishing and diagnosing RA, which reached a satisfactory performance in both training (AUC = 0.894) and testing (AUC = 0.843) cohorts. Two distinct subtypes of RA patients were identified, which further verified that these four signatures might be involved in the immune infiltration process. Furthermore, knockdown of CRTAM could significantly suppress the proliferation and invasion ability of RA cell line and thus could be treated as a novel therapeutic target. CRTAM owned a great diagnostic performance for RA than previous biomarkers including MMP3, S100A8, S100A9, IL6, COMP, LAG3, and ENTPD1. Mechanically, CRTAM could also be involved in the progression through immune dysfunction, fatty acid metabolism, and genomic instability across several cancer subtypes. Conclusion: CRTAM, PTTG1IP, ITGB2, and MMP13 were highly expressed in RA tissues and might function as pivotal diagnostic and treatment targets by deteriorating the immune dysfunction state. In addition, CRTAM might fuel cancer progression through immune signals, especially among RA patients.

Quercetin ameliorates oxidative stress-induced senescence in rat nucleus pulposus-derived mesenchymal stem cells via the miR-34a-5p/SIRT1 axis.

BACKGROUND: Intervertebral disc degeneration (IDD) is a main contributor to low back pain. Oxidative stress, which is highly associated with the progression of IDD, increases senescence of nucleus pulposus-derived mesenchymal stem cells (NPMSCs) and weakens the differentiation ability of NPMSCs in degenerated intervertebral discs (IVDs). Quercetin (Que) has been demonstrated to reduce oxidative stress in diverse degenerative diseases. AIM: To investigate the role of Que in oxidative stress-induced NPMSC damage and to elucidate the underlying mechanism. METHODS: In vitro, NPMSCs were isolated from rat tails. Senescence-associated ß-galactosidase (SA-ß-Gal) staining, cell cycle, reactive oxygen species (ROS), real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, and western blot analyses were used to evaluated the protective effects of Que. Meanwhile the relationship between miR-34a-5p and Sirtuins 1 (SIRT1) was evaluated by dual-luciferase reporter assay. To explore whether Que modulates tert-butyl hydroperoxide (TBHP)-induced senescence of NPMSCs via the miR-34a-5p/SIRT1 pathway, we used adenovirus vectors to overexpress and downregulate the expression of miR-34a-5p and used SIRT1 siRNA to knockdown SIRT1 expression. In vivo, a puncture-induced rat IDD model was constructed, and X rays and histological analysis were used to assess whether Que could alleviate IDD in vivo. RESULTS: We found that TBHP can cause NPMSCs senescence changes, such as reduced cell proliferation ability, increased SA-ß-Gal activity, cell cycle arrest, the accumulation of ROS, and increased expression of senescence-related proteins. While abovementioned senescence indicators were significantly alleviated by Que treatment. Que decreased the expression levels of senescence-related proteins (p16, p21, and p53) and senescence-associated secreted phenotype (SASP), including IL-1ß, IL-6, and MMP-13, and it increased the expression of SIRT1. In addition, the protective effects of Que on cell senescence were partially reversed by miR-34a-5p overexpression and SIRT1 knockdown. In vivo, X-ray, and histological analyses indicated that Que alleviated IDD in a puncture-induced rat model. CONCLUSION: In summary, the present study provides evidence that Que reduces oxidative stress-induced senescence of NPMSCs via the miR-34a/SIRT1 signaling pathway, suggesting that Que may be a potential agent for the treatment of IDD.

Comparative study of halo-vest reduction and skull traction reduction in the treatment of cervical fracture dislocation in patients with ankylosing spondylitis.

Background: This study aimed to investigate the safety and efficacy of the halo-vest in the treatment of cervical fracture in patients with ankylosing spondylitis (AS) and kyphosis. Methods: From May 2017 to May 2021, 36 patients with cervical fractures with AS and thoracic kyphosis were included in this study. The patients with cervical spine fractures with AS underwent preoperative reduction by halo-vest or skull tractions. Instrumentation internal fixation and fusion surgery were then performed. The level of cervical fractures, the operative duration, blood loss, and treatment outcomes were investigated preoperatively and postoperatively. Results: A total of 25 cases were included in the halo-vest group and 11 cases were included in the skull tractions group. The intraoperative blood loss and the surgery duration were significantly less in the halo-vest group than in the skull traction group. A comparison of American Spinal Injury Association scores at admission and final follow-up showed that the neurological function of patients improved in both groups. All patients had reached solid bony fusion during the follow-up. Conclusion: This study presented a unique approach to use halo-vest treatment fixation of unstable cervical fracture in patients with AS. The patient should also have early surgical stabilization with a halo-vest to correct spinal deformity and avoid worsening of neurological status.

The association of rod curvature with postoperative outcomes in patients undergoing posterior lumbar interbody fusion for spinal stenosis: a retrospective case-control study.

BACKGROUND: Restoration of sagittal balance is a crucial consideration in posterior lumbar interbody fusion (PLIF) surgery and adverse postoperative outcomes are associated with inadequate restoration of sagittal alignment. However, there remains a shortage of substantial evidence regarding the effect of rod curvature on both sagittal spinopelvic radiographic parameters and clinical outcomes. METHOD: A retrospective case-control study was conducted in this study. Patient demographics (age, gender, height, weight and BMI), surgical characteristics (number of fused levels, surgical time, blood loss and hospital stay) and radiographic parameters (lumbar lordosis [LL], sacral slope [SS], pelvic incidence [PI], pelvic tilt [PT], PI-LL, Cobb angle of fused segments [Cobb], rod curvature [RC], Posterior tangent angle of fused segments [PTA] and RC-PTA) were analyzed. RESULTS: Patients in the abnormal group had older mean age and suffered more blood loss than those in the normal group. In addition, RC and RC-PTA were significantly lower in the abnormal group compared to the normal group. Multivariate regression analysis revealed that lower age (OR = 0.94; 95% CI: 0.89-0.99; P = 0.0187), lower PTA (OR = 0.91; 95% CI: 0.85-0.96; P = 0.0015) and higher RC (OR = 1.35; 95% CI: 1.20-1.51; P < 0.0001) were related to higher odds of better surgical outcomes. The receiver operating characteristic curve analysis showed that the ROC curve (AUC) for predicting outcomes of surgery by RC classifier was 0.851 (0.769-0.932). CONCLUSIONS: In patients who underwent PLIF surgery for lumbar spinal stenosis, those who had a satisfactory postoperative outcome tended to be younger, had lower blood loss, and higher values of RC and RC-PTA compared to those who had poor recovery and required revision surgery. Additionally, RC was found to be a reliable predictor of postoperative outcomes.

Chitosan-based multifunctional hydrogel for sequential wound inflammation elimination, infection inhibition, and wound healing.

In this study, a composite hydrogel (QMPD hydrogel) composed of methacrylate anhydride (MA) grafted quaternary ammonium chitosan (QCS-MA), polyvinylpyrrolidone (PVP), and dopamine (DA) was designed for the sequential wound inflammation elimination, infection inhibition, and wound healing. The QMPD hydrogel formation was initiated by the ultraviolet light-triggered polymerization of QCS-MA. Furthermore, hydrogen bonds, electrostatic interactions, and "π-π" stacking between QCS-MA, PVP, and DA were involved in the hydrogel formation. In this hydrogel, the quaternary ammonium groups of quaternary ammonium chitosan and the photothermal conversion of polydopamine are capable of killing bacteria on wounds, which showed the bacteriostatic ratios of 85.6 % and 92.5 % toward Escherichia coli and Staphylococcus aureus, respectively. Moreover, the oxidation of DA sufficiently scavenged free radicals and introduced the QMPD hydrogel with good anti-oxidant and anti-inflammatory abilities. Together with the extracellular matrix-mimic tropical structure, the QMPD hydrogel significantly promoted the wound management of mice. Therefore, the QMPD hydrogel is expected to provide a new method for the design of wound healing dressings.

Sagittal Reconstruction of the Atlantoaxial Lateral Mass Complex with an Intra-Articular Cage Fusion Technique for Degenerative Atlantoaxial Instability.

OBJECTIVE: To evaluate outcomes of sagittal reconstruction of the atlantoaxial lateral mass complex using a modified intra-articular cage fusion technique for treating degenerative atlantoaxial instability. METHODS: Data from 15 patients with degenerative atlantoaxial instability were retrospectively reviewed. All patients underwent posterior reduction and intra-articular fusion with a cage filled with local autologous bone. Atlantodental interval values on plain radiography in flexion before and after surgery were recorded. Bone fusion was evaluated on computed tomography reconstruction, and bone fusion time was recorded. Lateral atlantoaxial joint space height before and after surgery was measured on coronal computed tomography reconstruction. Japanese Orthopaedic Association score and visual analog scale score for neck pain before surgery and at final follow-up were compared. RESULTS: Mean follow-up time was 40.7 ± 13.4 months. All patients achieved good reduction and solid bone fusion at follow-up. Mean fusion time was 4.4 ± 1.1 months. Atlantodental interval decreased from 8.6 ± 1.5 mm preoperatively to 1.9 ± 0.5 mm at final follow-up (P < 0.05). Lateral atlantoaxial joint space height significantly improved from 1.7 ± 0.5 mm preoperatively to 4.7 ± 0.3 mm at final follow-up (P < 0.05). Japanese Orthopaedic Association score significantly improved from 14.9 ± 1.5 preoperatively to 16.7 ± 0.6 at final follow-up (P < 0.05). Visual analog scale score for neck pain markedly decreased from 4.5 ± 1.8 preoperatively to 0.5 ± 0.6 at final follow-up (P < 0.05). CONCLUSIONS: Posterior reduction and intra-articular cage fusion with a C2 nerve root preservation technique is effective in treatment of degenerative atlantoaxial instability. Satisfactory reconstruction of the sagittal alignment and the height of atlantoaxial complex can be achieved.

Computational Drug Discovery in Ankylosing Spondylitis-Induced Osteoporosis Based on Data Mining and Bioinformatics Analysis.

BACKGROUND: Ankylosing spondylitis (AS) and osteoporosis (OP) are both prevalent illnesses in spine surgery, with OP being a possible consequence of AS. However, the mechanism of AS-induced OP (AS-OP) remains unknown, limiting etiologic research and therapy of the illness. To mine targetable medicine for the prevention and treatment of AS-OP, this study analyzes public data sets using bioinformatics to identify genes and biological pathways relevant to AS-OP. METHODS: First, text mining was used to identify common genes associated with AS and OP, after which functional analysis was carried out. The STRING database and Cytoscape software were used to create protein-protein interaction networks. Hub genes and potential drugs were discovered using drug-gene interaction analysis and transcription factors-gene interaction analysis. RESULTS: The results of text mining showed 241 genes common to AS and OP, from which 115 key symbols were sorted out by functional analysis. As options for treating AS-OP, protein-protein interaction analysis yielded 20 genes, which may be targeted by 13 medications. CONCLUSIONS: Carlumab, bermekimab, rilonacept, rilotumumab, and ficlatuzumab were first identified as the potential drugs for the treatment of AS-OP, proving the value of text mining and pathway analysis in drug discovery.

New Subtype of Atlantoaxial Rotatory Fixation (Type IIIa).

OBJECTIVE: Some atlantoaxial rotatory fixations (AARFs) cannot be classified according to the Fielding and Hawkins classification. This study aimed to introduce a new subtype of AARF (type IIIa AARF) with a C1 anterior displacement >5 mm, but with one lateral mass being displaced anteriorly and another posteriorly. METHODS: Data from 10 cases of AARF with anterior C1 displacement of >5 mm were retrospectively reviewed. The exclusion criteria were as follows: 1) type I, II, or IV AARF according to the Fielding and Hawkins classification; 2) cases caused by trauma, tumor, or infection; 3) AARF with os odontoideum or odontoid fracture; and 4）age ≥18 years. Imaging features were analyzed. The atlanto-dental interval was measured to evaluate C1 anterior displacement. RESULTS: Three cases that did not match type III AARF were classified under type IIIa AARF. They had the following common imaging features: 1) atlanto-dental interval of >5 mm, being similar to type III AARF; 2) one lateral mass of C1 displaced anteriorly and the other posteriorly (the most important feature distinguishing the type from type III AARF in which both C1 lateral masses displaced anteriorly); and 3) C1-C2 separation angle (mean 44.2 ± 2.9°) being larger than that in type III AARF. CONCLUSIONS: AARF with anterior C1 displacement of >5 mm, but with one lateral mass displaced anteriorly and the other posteriorly, was defined as type IIIa AARF. It should not be confused with type III AARF because these 2 types differ in biomechanics and imaging parameters.

Biomechanical Evaluation of the Cross-link Usage and Position in the Single and Multiple Segment Posterior Lumbar Interbody Fusion.

OBJECTIVE: Previous studies have neither explored the usage of cross-links nor investigated the optimal position of the cross-links in posterior lumbar interbody fusion (PLIF). This study evaluates biomechanical properties of cross-links in terms of different fixation segments and optimal position in single- and multi-segment posterior lumbar interbody fusion. METHODS: Two finite element (FE) models of instrumented lumbosacral spine with single-(L4/5) and multi-segment (L3-S1) PLIF surgery were simulated. On the basis of the two models, the benefits of the usage of cross-links were assessed and compared with the status of no application of cross-links. Moreover, the effects of position of cross-links on multi-segment PLIF surgery were studied in Upper, Middle, and Lower positions. RESULTS: No significant difference was found in the range of motion (ROM), intersegmental rotational angle (IRA) of adjacent segments, and intradiscal pressure (IDP) regardless of the usage of cross-links in the single-segment PLIF surgery, while the cross-link increased the maximum von Mises stress in the fixation (MSF) under the axial rotation (53.65 MPa vs 41.42 MPa). In the multi-segment PLIF surgery, the usage of cross-links showed anti-rotational advantages indicated by ROM (Without Cross-link 2.35o , Upper, 2.24o ; Middle, 2.26o ; Lower, 2.30o ) and IRA (Without Cross-link 1.19o , Upper, 1.08o ; Middle, 1.09o ; Lower, 1.13o ). The greatest values of MSF were found in without cross-link case under the flexion, lateral bending, and axial rotation (37.48, 62.61, and 86.73 MPa). The application of cross-links at the Middle and Lower positions had lower values of MSF (48.79 and 69.62 MPa) under the lateral bending and axial rotation, respectively. CONCLUSION: The application of cross-links was not beneficial for the single-segment PLIF, while it was found highly advantageous for the multi-segment PLIF. Moreover, the usage of cross-links at the Middle or Lower positions resulted in a better biomechanical stability.

Drug discovery in spinal cord injury-induced osteoporosis: a text mining-based study.

Background: Spinal cord injury (SCI) and osteoporosis (OP) are common diseases in spine surgery, and OP could be the complication of SCI. However, SCI-induced OP is a complex pathologic process and drug discovery is limited, which restricts the study in the mechanism and treatment of the disease. This study aims to identify the genes and molecular pathways related to SCI-induced OP through computational tools and public datasets, and to explore drug targeting therapy, ultimately preventing the occurrence of OP after SCI. Methods: In this study, common genes related to SCI and OP were obtained by text mining, then which conducted the functional analysis. Protein-protein interaction (PPI) networks were constructed by STRING online and Cytoscape software. Finally, core genes and potential drugs were performed after undergoing drug-gene interaction analysis which also completed functional analysis. Results: A total of 371 genes common to 'SCI' and 'OP' were identified by text mining. After functional analysis, 207 significant genes were screened out. Subsequently, PPI analysis yielded 23 genes targetable by 13 drugs which were the candidate to treat SCI-induced OP. Conclusions: Taken together, siltuximab, olokizumab, clazakizumab and BAN2401 were first discovered to become the potential drugs for the treatment of SCI-induced OP. Drug discovery using text mining and pathway analysis is a significant way to investigate the pathomechanism of the disease while exploring existing drugs to treat the disease.

1,25(OH)2D3 Mitigates Oxidative Stress-Induced Damage to Nucleus Pulposus-Derived Mesenchymal Stem Cells through PI3K/Akt Pathway.

Intervertebral disc degeneration (IVDD) is one of the main causes of low back pain. The local environment of the degenerated intervertebral disc (IVD) increases oxidative stress and apoptosis of endogenous nucleus pulposus-derived mesenchymal stem cells (NPMSCs) and weakens its ability of endogenous repair ability in degenerated IVDs. A suitable concentration of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) has been certified to reduce oxidative stress and cell apoptosis. The current study investigated the protective effect and potential mechanism of 1,25(OH)2D3 against oxidative stress-induced damage to NPMSCs. The present results showed that 1,25(OH)2D3 showed a significant protective effect on NPMSCs at a concentration of 10-10 M for 24 h. Protective effects of 1,25(OH)2D3 were also exhibited against H2O2-induced NPMSC senescence, mitochondrial dysfunction, and reduced mitochondrial membrane potential. The Annexin V/PI apoptosis detection assay, TUNEL assay, immunofluorescence, western blot, and real-time quantitative polymerase chain reaction assay showed that pretreatment with 1,25(OH)2D3 could alleviate H2O2-induced NPMSC apoptosis, including the apoptosis rate and the expression of proapoptotic-related (Caspase-3 and Bax) and antiapoptotic-related (Bcl-2) proteins. The intracellular expression of p-Akt increased after pretreatment with 1,25(OH)2D3. However, these protective effects of 1,25(OH)2D3 were significantly decreased after the PI3K/Akt pathway was inhibited by the LY294002 treatment. In vivo, X-ray, MRI, and histological analyses showed that 1,25(OH)2D3 treatment relieved the degree of IVDD in Sprague-Dawley rat disc puncture models. In summary, 1,25(OH)2D3 efficiently attenuated oxidative stress-induced NPMSC apoptosis and mitochondrial dysfunction via PI3K/Akt pathway and is a promising candidate treatment for the repair of IVDD.

Drug Discovery in Spinal Cord Injury With Ankylosing Spondylitis Identified by Text Mining and Biomedical Databases.

Spinal cord injury (SCI) and ankylosing spondylitis (AS) are common inflammatory diseases in spine surgery. However, it is a project where the relationship between the two diseases is ambiguous and the efficiency of drug discovery is limited. Therefore, the study aimed to investigate new drug therapies for SCI and AS. First, text mining was used to obtain the interacting genes related to SCI and AS, and then, the functional analysis was conducted. Protein-protein interaction (PPI) networks were constructed by STRING online and Cytoscape software to identify hub genes. Last, hub genes and potential drugs were performed after undergoing drug-gene interaction analysis, and MicroRNA and transcription factors regulatory networks were also analyzed. Two hundred five genes common to "SCI" and "AS" identified by text mining were enriched in inflammatory responses. PPI network analysis showed that 30 genes constructed two significant modules. Ultimately, nine (SST, VWF, IL1B, IL6, CXCR4, VEGFA, SERPINE1, FN1, and PROS1) out of 30 genes could be targetable by a total of 13 drugs. In conclusion, the novel core genes contribute to a novel insight for latent functional mechanisms and present potential prognostic indicators and therapeutic targets in SCI and AS.

Biomechanical and Clinical Study of Rod Curvature in Single-Segment Posterior Lumbar Interbody Fusion.

Objective: Pedicle screw fixation is a common technique used in posterior lumbar interbody fusion (PLIF) surgery for lumbar disorders. During operation, rod contouring is often subjective and not satisfactory, but only few studies focused on the rod-contouring issue previously. The aim of the study was to explore the effect of the rod contouring on the single-segment PLIF by the finite element (FE) method and retrospective study. Methods: A FE model of the lumbosacral vertebrae was first reconstructed, and subsequently single-segmental (L4/5) PLIF surgeries with four rod curvatures (RCs) were simulated. Herein, three RCs were designed by referring to centroid, Cobb, and posterior tangent methods applied in the lumbar lordosis measurement, and zero RC indicating straight rods was included as well. Clinical data of patients subjected to L4/5 segmental PLIF were also analyzed to verify the correlation between RCs and clinical outcome. Results: No difference was observed among the four RC models in the range of motion (ROM), intersegmental rotation angle (IRA), and intradiscal pressure (IDP) under four actions. The posterior tangent model had less maximum stress in fixation (MSF) in flexion, extension, and axial rotation than the other RC models. Patients with favorable prognosis had larger RC and positive RC minus posterior tangent angle (RC-PTA) of fused segments with respect to those who had poor prognosis and received revision surgery. Conclusion: All RC models had similar biomechanical behaviors under four actions. The posterior tangent-based RC model was superior in fixation stress distribution compared to centroid, Cobb, and straight models. The retrospective study demonstrated that moderate RC and positive RC-PTA were associated with better postoperative results.

Cervical Myelopathy Due to Idiopathic Retro-odontoid Pseudotumor.

OBJECTIVE: A retro-odontoid pseudotumor (ROP) is commonly associated with atlantoaxial instability or rheumatoid arthritis. However, ROP in the absence of atlantoaxial instability or rheumatoid arthritis, which is termed idiopathic ROP (IROP), is a rare condition. The pathomechanisms and optimal treatment strategies for IROP remain controversial. The aim of the present study was to evaluate the radiographic and clinical characteristics of IROP patients and to assess the efficiency of atlantoaxial/occipitocervical fusion on IROP regression. METHODS: Data from 5 patients diagnosed with IROP were retrospectively reviewed. Posterior atlantoaxial or occipitocervical fixation and fusion were performed in 4 patients and C1 posterior arch resection alone in 1 patient. The patients' features, surgical procedures, and complications were recorded. The retro-odontoid soft tissue thickness was measured on preoperative and postoperative magnetic resonance imaging to evaluate IROP regression. RESULTS: The mean follow-up time was 37 months. ROP regression was achieved in patients who received atlantoaxial/occipitocervical fusion, but not for the patient with C1 posterior resection alone. There were no observed neurovascular complications associated with surgery. CONCLUSIONS: IROP was related to a restricted range of motion of the subaxial spine. Upper cervical fixation is an optional treatment that produces IROP regression over time. By contrast, direct removal of the IROP is unnecessary.

Anterior Canal Reconstruction and Fusion for Myelopathy Caused by Degenerative Cervical Kyphosis and Stenosis With or Without Ossification of the Posterior Longitudinal Ligament.

STUDY DESIGN: This was a retrospective study. OBJECTIVE: To introduce an anterior surgical technique for myelopathy caused by degenerative cervical kyphosis and stenosis (DCKS) with or without ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: The optimal approach in the treatment of DCKS remains a controversy because each anterior or posterior route surgery has advantages and disadvantages. MATERIALS AND METHODS: In the period from June 2017 through June 2019, a consecutive cohort of adults diagnosed with DCKS underwent anterior canal reconstruction and fusion (ACRF). All patients underwent x-ray, computed tomography, and magnetic resonance imaging of the cervical spine. Radiologic assessment included kyphosis, canal area, canal reconstruction, OPLL, and spinal cord curvature and morphology. The Japanese Orthopaedic Association (JOA) scoring system was used to evaluate the neurological status. Surgery-related and implant-related complications were all recorded. Follow-up was carried out at 3, 6, 12, 24, and 36 months postoperation. RESULTS: Fourty-one patients were included in the study, of which 19 presented with OPLL. Postoperatively, the canal area were significantly greater at last follow-up compared with preoperation (208.4 vs. 123.2 mm2; P=0.001). There was significant kyphosis correction (-17.6 vs. 8.5 degrees, P=0.001) at last follow-up. Ninety-six segmental canal reconstruction were performed, 89 (92.7%) reached bone fusion at both grooves with a mean time of 7.9 months. On sagittal magnetic resonance imaging, 33 (80.5%) patients presented with lordosis in the spinal cord curvature, 8 (19.5%) with straight. The mean JOA score at last follow-up was significantly better than preoperation (15.0 vs. 9.3 points; P<0.01). One patient presented with cerebrospinal fluid leakage, 1 with screw displacement and 2 with dysphagia. CONCLUSION: ACRF, receiving good correction of kyphosis, amplified canal area, solid instrumented fusion and circumferential decompression, is an effective and safe surgical technique for cervical myelopathy caused by DCKS with or without OPLL. LEVEL OF EVIDENCE: Level III-a retrospective analysis.

Cervical spine fracture-dislocation in patients with ankylosing spondylitis and severe thoracic kyphosis: Application of halo vest before and during surgical management.

Cervical spine fracture-dislocation in patients with ankylosing spondylitis (AS) and severe thoracic kyphosis is extremely unstable. This study was performed to investigate the efficacy and safety of halo vest application before and during surgery for these patients. We retrospectively analyzed the case histories, operations, neurologic outcomes, follow-up data, and imaging records of 25 patients with AS and severe thoracic kyphosis who underwent surgical treatment of cervical fracture-dislocation in our department from 2008 to 2019. A halo vest was used to reduce and immobilize the fractured spinal column ends before and during surgery. The neurologic injury was evaluated using the American Spinal Injury Association (ASIA) impairment scale score, visual analog scale (VAS) score, and Japanese Orthopaedic Association (JOA) score before and after the operation. Twenty-two patients achieved closed anatomical reduction; two achieved successful reduction and one underwent failed reduction after halo vest application. No fracture site displacement occurred after movement into the prone position. No patients developed secondary neurological deterioration. The mean Cobb angle of thoracic kyphosis was 69.0° ± 12.3°. All patients underwent posterior or combined anterior-posterior surgery. The ASIA grade improved significantly (P < 0.01). The mean VAS and JOA scores also increased significantly after the operation (14.6 ± 3.0 vs. 10.4 ± 4.3 and 0.5 ± 0.6 vs. 4.6 ± 1.9, respectively; P < 0.01). One patient died 3 weeks after the operation. No other severe complications occurred. All patients had reached solid bony fusion by the 12-month follow-up. Use of a halo vest before and during the operation is safe and effective in patients with AS and severe thoracic kyphosis who develop cervical fracture-dislocation. This technique makes positioning, awake nasoendotracheal intubation, nursing, and the operation more convenient. It can also provide satisfactory reduction and rigid immobilization and prevent secondary neurologic deterioration.

Alcohol Abuse and Alcohol Withdrawal Are Associated with Adverse Perioperative Outcomes Following Elective Spine Fusion Surgery.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: Alcohol abuse (AA) and alcohol withdrawal (AW), both belonging to alcohol use disorders, bring about vast health consequences, social issues, and financial burden in United States. This study aims to explore the relationship of AA and AW with perioperative outcomes following elective spine fusion surgery. SUMMARY OF BACKGROUND DATA: Large studies evaluating the outcomes of spine surgery in patients with AA or AW are lacking. METHODS: We used the National Inpatient Sample (NIS) from 2006 to 2014 to extract records with a primary procedure of spinal fusion surgery. Multivariable regression analysis was used to assess the association of AA and AW with in-hospital mortality, perioperative complications, cost and length of stay (LOS). RESULTS: Among 3,132,192 patients undergoing elective spinal fusion surgery, the prevalence of AA and AW was 1.14% (35,833) and 0.15% (4623), respectively. Among the AA admissions, 12.90% of patients developed AW. The incidence of overall complications was 6.14%, 10.15%, and 33.73% in patients without AA, with AA and with AW, respectively. After multivariable adjustment, AW was associated with elevated risk of overall complications (odds ratio [OR]: 4.51; 95% confidence interval [CI]: 3.86-5.27), neurologic (OR: 2.58; 95% CI: 1.62-4.12), respiratory (OR: 8.04; 95% CI: 6.62-9.77), cardiac (OR: 3.58; 95% CI: 2.60-4.93), gastrointestinal (OR: 2.31; 95%CI: 1.68-3.17), urinary and renal (OR: 2.68; 95% CI: 2.11-3.39), venous thromboembolism (OR: 3.06; 95% CI: 1.94-4.82), wound-related complications (OR: 3.84; 95% CI: 2.96-4.98) and in-hospital mortality (OR: 5.95; 95% CI: 3.25-10.90). AW was also linked to 40% higher cost and 85% longer LOS. CONCLUSION: Both AA and AW are associated with adverse outcomes in patients undergoing spinal fusion surgery with more pronounced risks for AW. Aggressive management in perioperative period is required to improve outcomes in these patients.Level of Evidence: 3.