Restoring the ideal Roussouly sagittal alignment in Lenke 5 adolescent idiopathic scoliosis patients: a method for decreasing the risk of proximal junctional kyphosis.

PURPOSE: Although the Roussouly classification has been widely used in surgical planning for adult scoliosis patients, little is known about whether it can be used to guide sagittal correction for adolescent idiopathic scoliosis (AIS) patients. The purpose of this study was to explore whether the Roussouly classification could be used to help surgeons restore the ideal sagittal alignment for AIS patients to avoid the development of proximal junctional kyphosis (PJK). METHODS: In this retrospective cohort study, eighty-seven patients with Lenke 5 AIS who underwent surgery from January 2010 to August 2020 were enrolled and divided into two groups: the PJK group and the non-PJK group. All patients were classified into "current types" and "ideal types" according to two versions of the Roussouly classification, and the mismatch rate was evaluated in terms of the consistency between their current type and ideal type. Student's t test, Mann‒Whitney U test, Pearson's Chi-square test, and others were used to compare the two groups regarding patient demographic characteristics (age, sex, Risser sign, etc.) and radiographic parameters (sagittal vertical axis [SVA]; thoracic kyphosis [TK]; thoracolumbar junctional kyphosis [TLK]; lumbar lordosis [LL]; pelvic incidence [PI]; pelvic tilt [PT]; sacral slope [SS]; upper instrumented vertebra [UIV]; lower instrumented vertebra [LIV]; etc.). Multivariate logistic regression with backwards stepwise selection was performed to identify the risk factors for PJK. RESULTS: PJK was observed in 16 out of 87 patients (18.4%) until the final follow-up. The incidence of PJK was significantly higher in the patients not matching their ideal type than in those who did after surgery (60.9% vs. 3.1%, p = 0.000). The patients with ideal Type 1 had the highest incidence of PJK, while the lowest incidence was observed in patients with ideal Type 2 (50.0% vs. 5.1%, p = 0.000). The PJK group had greater TK, LL, and PI-LL than the non-PJK group before and after surgery. The postoperative PJA in the PJK group was also larger than that in the non-PJK group. Multivariate logistic regression revealed that postoperative Roussouly type mismatch was significantly associated with the occurrence of PJK (OR = 64.2, CI = 9.6-407.1, p = 0.000). CONCLUSIONS: The Roussouly classification could serve as a prognostic tool for PJK in Lenke 5 AIS patients. Corrective surgery should restore sagittal alignment with respect to the patient's ideal sagittal profile (according to the Roussouly classification based on the PI) to decrease the incidence of PJK in AIS patients.

A novel MRI-based Cervical-Endplate Bone Quality score independently predicts cage subsidence after Anterior Cervical Discectomy and Fusion.

INTRODUCTION: Postoperative cage subsidence after Anterior Cervical Discectomy and Fusion (ACDF) often has adverse clinical consequences and is closely related to Bone Mineral Density (BMD). Previous studies have shown that cage subsidence can be better predicted by measuring site-specific bone density. MRI-based Endplate Bone Quality (EBQ) scoring effectively predicts cage subsidence after lumbar interbody fusion. However, there is still a lack of studies on the practical application of EBQ scoring in the cervical spine. PURPOSE: To create a similar MRI-based scoring system for Cervical-EBQ (C-EBQ) and to assess the correlation of the C-EBQ with endplate Computed Tomography (CT)-Hounsfield Units (HU) and the ability of this scoring system to independently predict cage subsidence after ACDF, comparing the predictive ability of the C-EBQ with the Cervical-Vertebral Bone Quality (C-VBQ) score. METHODS: A total of 161 patients who underwent single-level ACDF for degenerative cervical spondylosis at our institution from 2012 to 2022 were included. Demographics, procedure-related data, and radiological data were collected, and Pearson correlation test was used to determine the correlation between C-EBQ and endplate HU values. Cage subsidence was defined as fusion segment height loss of ≥ 3 mm. Receiver operating characteristic analysis and area-under-the-curve values were used to assess the predictive ability of C-EBQ and C-VBQ. A multivariate logistic regression model was developed to identify potential risk factors associated with subsidence. RESULTS: Cage subsidence was present in 65 (40.4%) of 161 patients. The mean C-EBQ score was 1.81 ± 0.35 in the group without subsidence and 2.59 ± 0.58 in the group with subsidence (P < 0.001). Multivariate analysis showed that a higher C-EBQ score was significantly associated with subsidence (OR = 5.700; 95%CI = 3.435-8.193; P < 0.001), was the only independent predictor of cage subsidence after ACDF, had a predictive accuracy of 93.7%, which was superior to the C-VBQ score (89.2%), and was significantly negatively correlated with the endplate HU value (r = -0.58, P < 0.001). CONCLUSIONS: Higher C-EBQ scores were significantly associated with postoperative cage subsidence after ACDF. There was a significant negative correlation between C-EBQ and endplate HU values. The C-EBQ score may be a promising tool for assessing preoperative bone quality and postoperative cage subsidence and is superior to the C-VBQ.

Simplified S1 vertebral bone quality (vbq) score to assess proximal junctional kyphosis after Lenke 5 adolescent idiopathic scoliosis surgery.

BACKGROUND: Proximal junctional kyphosis (PJK) is a common complication following corrective surgery for adolescent idiopathic scoliosis (AIS) with a Lenke 5 curve. Previous studies have suggested that PJK may be associated with osteopenia, which is prevalent in AIS patients. MRI-based vertebral bone quality (VBQ) scores have been proposed as a valuable tool to assess preoperative bone quality. However, accurately measuring VBQ scores in Lenke 5 AIS patients with a structural lumbar curve can be challenging. Recently, a simplified S1 VBQ score has been proposed as an alternative method when the traditional VBQ score is not applicable. This study aims to evaluate the predictive value of the simplified S1 VBQ score in predicting the occurrence of PJK after corrective surgery for Lenke 5 AIS. METHODS: We conducted a retrospective analysis of patient data to assess the predictive utility of the S1 VBQ score for PJK in Lenke 5 AIS patients. Demographic, radiographic, and surgical data were collected, and S1 VBQ scores were calculated based on preoperative T1-weighted MRI images. Univariate analysis, linear regression, and multivariate logistic regression were performed to identify potential risk factors for PJK and to assess the correlation between other variables and the S1 VBQ score. Receiver operating characteristic analysis and area under the curve values were used to evaluate the predictive efficiency of the S1 VBQ score for PJK. RESULTS: A total of 105 patients (aged 15.50 ± 2.36 years) were included in the analysis, of whom 24 (22.9%) developed PJK. S1 VBQ scores were significantly higher in the PJK group compared to the non-PJK group (2.83 ± 0.44 vs. 2.48 ± 0.30, P < 0.001), and there was a significant positive correlation between the S1 VBQ score and proximal junctional angle (PJA) (r = 0.46, P < 0.0001). Multivariate analysis revealed that the S1 VBQ scores and preoperative thoracic kyphosis (TK) were significant predictors of PJK. CONCLUSION: This study provided evidence that higher S1 VBQ scores were independently associated with PJK occurrence following corrective surgery for Lenke 5 AIS. Preoperative measurement of the S1 VBQ score on MRI may serve as a valuable tool in planning surgical correction for Lenke 5 AIS.

Novel MRI signs of the atlantodental space in patients with atlantoaxial dislocation.

OBJECTIVES: The type of atlantodental space tissue in patients with atlantoaxial dislocation (AAD) can help doctors understand the possibility of reduction before surgery. However, relevant research on this topic is lacking. In this study, we aimed to summarise the atlantodental space classification of patients with AAD using magnetic resonance imaging (MRI) and explore their clinical characteristics. MATERIALS AND METHODS: Preoperative 3T cervical MR images of patients who underwent posterior reduction and fixation surgery for non-traumatic AAD between 1 September 2012 and 31 July 2023 were collected. Two radiologists read and recorded the MRI results based on the standard protocol. The kappa value was used to evaluate intra- and inter-observer agreements. The patient's age, sex, body mass index, clinical symptoms, Japanese Orthopaedic Association (JOA) score, and visual analogue scale information were obtained from medical records. RESULTS: A total of 135 patients with AAD (mean age, 51.3 ± 14.0 years, 52 men) were included in the analysis. The inter-observer agreement between the two readers was 0.818 (P < 0.0001). The intra-observer consistencies were 0.882 (P < 0.0001) and 0.896 (P < 0.0001). Patients with inflexible tissue signs exhibit more irreducible in hyperextension position, and their range of motion of ADI is smaller. These patients were older and had a higher incidence of abnormal spinal cord signals and JOA scores. CONCLUSIONS: Novel MRI signs exhibited high inter- and intra-observer consistency and were associated with patient age, abnormal spinal cord signals, reducibility, range of motion of ADI, and symptoms.

Preoperative geriatric nutritional risk index is useful factor for predicting postoperative delirium among elderly patients with degenerative lumbar diseases.

PURPOSE: It is the first study to evaluate the predictive value of the geriatric nutritional risk index (GNRI) on postoperative delirium (POD) after transforaminal lumber interbody fusion (TLIF) in elderly patients with degenerative lumbar diseases. METHODS: A retrospective study was conducted to assess the outcomes of TLIF surgery in elderly patients with lumbar degenerative disease between the years 2016 and 2022. Delirium was diagnosed by reviewing postoperative medical records during hospitalization, utilizing the Confusion Assessment Method. The geriatric nutritional risk index was calculated using the baseline serum albumin level and body weight. Multivariate logistic regression analysis was employed to identify the association between preoperative GNRI and postoperative delirium (POD). Additionally, a receiver operating characteristic curve was utilized to determine the optimal GNRI cutoff for predicting POD. RESULTS: POD was observed in 50 of the 324 patients. The GNRI was visibly reduced in the delirium group. The mean GNRI was 93.0 ± 9.1 in non-delirium group and 101.2 ± 8.2 in delirium group. On multivariate logistic regression, Risk of POD increases significantly with low GNRI and was an independent factor in predicting POD following TLIF (OR 0.714; 95% CI 0.540-0.944; p = 0.018). On receiver operating characteristic curve, the area under curve (AUC) for GNRI was 0.738 (95% CI 0.660-0.817). The cutoff value for GNRI according to the Youden index was 96.370 (sensitivity: 66.0%, specificity: 70.4%). CONCLUSION: Our study indicated that lower GNRI correlated significantly with POD after TLIF. Performing GNRI evaluation prior to TLIF may be an effective approach of predicting the risk for POD among elderly patients with degenerative lumbar diseases.

A novel cervical vertebral bone quality score can independently predict cage subsidence after anterior cervical corpectomy and fusion.

OBJECTIVES: To optimize cervical vertebral bone quality (C-VBQ) score and explore its effectiveness in predicting cage subsidence in Anterior Cervical Corpectomy and Fusion (ACCF) and identify a new method for evaluating subsidence without different equipment and image scale interference. METHODS: Collecting demographic, imaging, and surgical related information. Measuring Cage Subsidence with a new method. Multifactorial logistic regression was used to identify risk factors associated with subsidence. Pearson's correlation was used to determine the relationship between C-VBQ and computed tomography (CT) Hounsfield units (HU). The receiver operating characteristic (ROC) curve was used to assess C-VBQ predictive ability. Correlations between demographics and C-VBQ scores were analyzed using linear regression models. RESULTS: 92 patients were included in this study, 36 (39.1%) showed subsidence with a C-VBQ value of 2.05 ± 0.45, in the no-subsidence group C-VBQ Value was 3.25 ± 0.76. The multifactorial logistic regression showed that C-VBQ is an independent predictor of cage subsidence with a predictive accuracy of 93.4%. Pearson's correlation analysis showed a negative correlation between C-VBQ and HU values. Linear regression analysis showed a positive correlation between C-VBQ and cage subsidence. Univariate analyses showed that only age was associated with C-VBQ. CONCLUSIONS: The C-VBQ values obtained using the new measurements independently predicted postoperative cage subsidence after ACCF and showed a negative correlation with HU values. By adding the measurement of non-operated vertebral heights as a control standard, the results of cage subsidence measured by the ratio method are likely to be more robust, perhaps can exclude unavoidable errors caused by different equipment and proportional.

The effect of brace treatment history on bone density in preoperative patients with adolescent idiopathic scoliosis (AIS) assessed by vertebral bone quality (VBQ) score: a retrospective propensity score-matched analysis.

INTRODUCTION: Adolescent idiopathic scoliosis (AIS), a prevalent condition among teenagers, is often accompanied by osteopenia. However, the impact of brace treatment on bone density in AIS patients remains a matter of debate. The Vertebral bone quality (VBQ) score, derived from MRI signal intensity, has been shown to correlate with bone mineral density (BMD). Yet, no studies to date have drawn comparisons between VBQ scores in preoperative AIS patients who had brace treatment history and those who have not received brace treatment. OBJECTIVE: This study aims to elucidate the influence of brace treatment on bone density in AIS patients using VBQ score. METHODS: A retrospective analysis was conducted on 243 AIS patients, each with Cobb angles ranging from 50-70°, who had undergone preoperative MRI scans. The patients were segregated into two cohorts: those who received brace treatment (n = 174) and those who did not (n = 69). Through propensity score matching, a total of 53 matched pairs were selected for further analysis. VBQ scores were extracted from T1-weighted MRI scans. RESULTS: Post-matching, no significant baseline discrepancies were observed between the two groups. Interestingly, brace-treated patients exhibited lower average VBQ scores than their non-brace-treated counterparts (2.43 ± 0.11 vs. 2.55 ± 0.12, p < 0.01), suggesting a higher bone density. Furthermore, a negative correlation was observed between VBQ scores and the duration of brace usage (R2 = 0.3853, p < 0.01). CONCLUSION: Brace treatment may potentially enhance bone density in AIS patients by mitigating vertebral fat infiltration. The utilization of VBQ scores presents an alternative, potentially robust approach to assessing bone quality.

CVTrack: Combined Convolutional Neural Network and Vision Transformer Fusion Model for Visual Tracking.

Most single-object trackers currently employ either a convolutional neural network (CNN) or a vision transformer as the backbone for object tracking. In CNNs, convolutional operations excel at extracting local features but struggle to capture global representations. On the other hand, vision transformers utilize cascaded self-attention modules to capture long-range feature dependencies but may overlook local feature details. To address these limitations, we propose a target-tracking algorithm called CVTrack, which leverages a parallel dual-branch backbone network combining CNN and Transformer for feature extraction and fusion. Firstly, CVTrack utilizes a parallel dual-branch feature extraction network with CNN and transformer branches to extract local and global features from the input image. Through bidirectional information interaction channels, the local features from the CNN branch and the global features from the transformer branch are able to interact and fuse information effectively. Secondly, deep cross-correlation operations and transformer-based methods are employed to fuse the template and search region features, enabling comprehensive interaction between them. Subsequently, the fused features are fed into the prediction module to accomplish the object-tracking task. Our tracker achieves state-of-the-art performance on five benchmark datasets while maintaining real-time execution speed. Finally, we conduct ablation studies to demonstrate the efficacy of each module in the parallel dual-branch feature extraction backbone network.

Tetrahedral Framework Nucleic Acids Inhibit Muscular Mitochondria-Mediated Apoptosis and Ameliorate Muscle Atrophy in Sarcopenia.

Sarcopenia is known as age-related muscle atrophy, which influences over a quarter of the elderly population worldwide. It is characterized by a progressive decline in muscle mass, strength, and performance. To date, clinical treatments in sarcopenia are limited to rehabilitative interventions and dietary supplements. Tetrahedral framework nucleic acids (tFNAs) represent a novel kind of DNA-based nanomaterial with superior antiapoptosis capacity in cells, tissues, organs, and systems. In our study, the therapeutic effect of tFNAs treatment on sarcopenia was evaluated both in vivo and in vitro. Results from muscular biophysiological characteristics demonstrated significant improvement in muscle function and endurance in the aged mouse model, and histologic examinations also showed beneficial morphological changes in muscle fibers. In vitro, DEX-induced sarcopenic myotube atrophy was also ameliorated through the inhibition of mitochondria-mediated cell apoptosis. Collectively, tFNAs treatment might serve as an alternative option to deal with sarcopenia in the near future.

Lentivirus-shRNA Mediated Prolyl Hydroxylase 2 Knockdown Increases HIF-1α and Inhibits Nucleus Pulposus Cells Degeneration.

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

The preoperative Hounsfield unit value at the position of the future screw insertion is a better predictor of screw loosening than other methods.

OBJECTIVE: Screw loosening is a widely reported issue after spinal screw fixation and triggers several complications after lumbar interbody fusion. Osteoporosis is an essential risk factor for screw loosening. Hounsfield units (HU) value is a credible indicator during bone mineral density (BMD) evaluation. As compared with the general evaluation of BMD, we hypothesized that specific measurements of HU at the precise location of the future screw insertion may be a better predictor of screw loosening. METHODS: Clinical data of 56 patients treated by oblique lumbar interbody fusion (OLIF) of the L4-L5 segments with an anterior lateral single rod (ALSR) screw fixation were reviewed in this study. Vertebral bodies with ≥ 1 mm width radiolucent zones around the screw were defined as screw loosening. HU in the insertional screw positions, the central transverse plane, and the average values of three and four planes were measured. Regression analyses identified independent risk factors for screw loosening separately. The area under the receiver operating characteristic curve (AUC) was computed to evaluate predictive performance. RESULTS: The local HU values were significantly lower in the loosening group, regardless of the selected measuring methods. The AUC of screw loosening prediction was higher in the insertional screw positions' HU than other frequently used methods. CONCLUSIONS: The HU value measured in the insertional screw position is a better predictor of ALSR screw loosening than other methods. The risk of screw loosening should be reduced by optimizing the trajectory of the screw based on the measurement of HU in preoperative CT. KEY POINTS: • Osteoporosis is an essential risk factor for screw loosening, and Hounsfield units (HU) are a credible predictor during bone mineral density (BMD) evaluation. • The HU value measured in the insertional screw position is a better predictor of screw loosening than other frequently used HU measurement methods. • The risk of screw loosening might potentially be reduced by optimizing the trajectory of the screw based on the measurement of HU in preoperative CT.

Posterior concave reconstruction with cage in the surgical treatment of complex lumbar deformity caused by lumbosacral hemivertebrae.

PURPOSE: To identify the clinical and radiological outcomes in the coronal and sagittal planes after treatment of congenital complex lumbosacral hemivertebrae (LSHV) with or without posterior concave reconstruction. METHODS: We retrospectively reviewed a consecutive series of patients with congenital LSHV deformities treated by posterior-only hemivertebra resection. The minimum follow-up was 2 years. The patients were divided into a concave-cage group and a non-cage group. The radiographic and clinical results were compared between the two groups. RESULTS: Forty patients were categorized into the cage group (n = 14) and non-cage group (n = 26). At the end of the propensity score matching analysis, 14 patients from the cage group were matched to 14 patients in the non-cage group. The lumbosacral curve and thoracolumbar/lumbar curve improved significantly in both groups at the final postoperative follow-up (P < 0.001), and the lumbosacral curve at the final follow-up was remarkably lower in the cage than non-cage group. The correction rates of the lumbosacral curve and thoracolumbar/lumbar curve were significantly higher in the cage than non-cage group. The lower lumbar lordosis improved significantly in both groups at the final postoperative follow-up (P < 0.05), and the lower lumbar lordosis at the final follow-up and its correction were remarkably higher in the cage than non-cage group (both P < 0.05). CONCLUSIONS: Posterior column reconstruction with insertion of a concave cage may achieve a higher correction rate of large lower lumbar lordosis and lumbosacral coronal deformity, attain better sagittal balance, and have fewer complications related to implant failure than posterior-only hemivertebra resection in patients with congenital LSHV.

Vertebral bone quality score as a novel predictor of proximal junctional kyphosis after thoracic adolescent idiopathic scoliosis surgery.

INTRODUCTION: Proximal junctional kyphosis (PJK) is one of the most common complications after thoracic AIS surgery. Previous studies reported that the etiology of PJK was associated with osteopenia and meanwhile the AIS patients were found osteopenia which could persist into adulthood. Recently, an MRI-based vertebral bone quality score (VBQ) was reported to be a promising tool which can assess preoperative bone quality. OBJECTIVE: This study aims to evaluate the utility of VBQ score in predicting PJK after corrective surgery for thoracic AIS (Lenke 1 and 2). METHODS: We conducted a retrospective study to identify the predictive efficiency of VBQ score for PJK in thoracic AIS patients. Demographic, radiographic parameters, and surgical variables were collected. VBQ score was calculated using preoperative T1-weighted MRI. Univariate analysis, linear regression, and multivariate logistic regression were performed to determine potential risk factors of PJK and correlation between other parameters and VBQ score. Receiver operating characteristic analysis and area under the curve values were utilized to evaluate the predictive efficiency of VBQ score for PJK. RESULTS: A total of 206 patients (aged 14.4 ± 2.3 years) were included, of which 33 (16.0%) developed PJK. VBQ scores were significantly different between the PJK and non-PJK groups (2.8 ± 0.2 vs 2.5 ± 0.2, P < 0.01). A significant positive correlation was found between VBQ score and PJA (R2 = 0.1728, P < 0.01).On multivariate analysis, VBQ score was the only significant predictor of PJK (odds ratio = 2.178, 95% CI = 1.644-2.885, P < 0.001), with a predictive accuracy of 83%. CONCLUSION: Higher VBQ scores were independently associated with PJK occurrence after corrective surgery for thoracic AIS. Preoperative measurement of VBQ score on MRI may serve as a valuable tool in planning thoracic AIS surgery.

MRI-based vertebral bone quality score for predicting cage subsidence by assessing bone mineral density following transforaminal lumbar interbody fusion: a retrospective analysis.

PURPOSE: This is the first study to evaluate the predictive value of the vertebral bone quality (VBQ) score on cage subsidence after transforaminal lumbar interbody fusion (TLIF) in a Chinese population using the spinal quantitative computed tomography (QCT) as the clinical standard. Meanwhile, the accuracy of the MRI-based VBQ score in bone mineral density (BMD) measurement was verified. METHODS: We performed a retrospective study of patients who underwent single-level TLIF from 2015 to 2020 with at least 1 year of follow-up. Cage subsidence was measured using postoperative radiographic images based on cage protrusion through the endplates more than 2 mm. The VBQ score was measured on T1-weighted MRI. The results were subjected to statistical analysis. RESULTS: A total of 283 patients (61.1% of female) were included in the study. The subsidence rate was with 14.1% (n = 40), and the average cage subsidence was 2.3 mm. There was a significant difference in age, sex, VBQ score and spinal QCT between the subsidence group and the no-subsidence group. The multivariable analysis demonstrated that only an increased VBQ score (OR = 2.690, 95% CI 1.312-5.515, p = 0.007) and decreased L1/2 QCT-vBMD (OR = 0.955, 95% CI 0.933-0.977, p < 0.001) were associated with an increased rate of cage subsidence. The VBQ score was found to be moderately correlated with the spinal QCT (r = -0.426, p < 0.001). The VBQ score was shown to significantly predict cage subsidence, with an accuracy of 82.5%. CONCLUSION: Our findings indicate that the MRI-based VBQ score is a significant predictor of cage subsidence and could be used to assess BMD.

Meglumine cyclic adenylate improves cardiovascular hemodynamics and motor-function in a rat model of acute T4 thoracic spinal cord injury.

STUDY DESIGN: Animal experimental study. OBJECTIVES: Spinal cord injury (SCI) at or above the T6 level causes cardiovascular dysfunction. Maintaining cAMP levels with cAMP analogs can facilitate neurological recovery. In the present study, the effects of meglumine cyclic adenylate (MCA), a cAMP analog and approved cardiovascular drug, on cardiovascular and neurological recovery in acute T4-SCI in rats were investigated. SETTING: Hospital in Kunming, China. METHODS: Eighty rats were randomly allocated to five groups, and groups A-D received SCI: (A) a group administered MCA at 2 mg/kg/d iv qd, (B) a group administered dopamine at 2.5 to 5 µg/kg/min iv to maintain mean arterial pressure above 85 mm Hg, (C) a group administered atropine at 1 mg/kg iv bid, (D) a group receiving an equal volume of saline iv qd for 3 weeks after SCI and (E) a group undergoing laminectomy only. The cardiovascular and behavioral parameters of the rats were examined, and spinal cord tissues were processed for hematoxylin and eosin staining, Nissl staining, electron microscopy, and analysis of cAMP levels. RESULTS: Compared with dopamine or atropine, MCA significantly reversed the decrease in cAMP levels in both myocardial cells and the injured spinal cord; improved hypotension, bradycardia and behavioral parameters at 6 weeks; and improved spinal cord blood flow and histological structure at 7 days post-SCI. The regression analysis suggested spinal cord motor-function improved as decreased heart rate and mean arterial pressure were stopped post-SCI. CONCLUSIONS: MCA may be an effective treatment for acute SCI by sustaining cAMP-dependent reparative processes and improving post-SCI cardiovascular dysfunction. SPONSORSHIP: N/A.

Tranexamic acid can reduce blood loss in adolescent scoliosis surgery: a systematic review and meta-analysis.

BACKGROUND: Tranexamic acid (TXA) has been widely used in orthopedic surgery, but its efficacy in adolescent scoliosis (AS) surgery remains unclear in the literature. The purpose of this systematic review and meta-analysis is to evaluate the safety and efficacy of TXA compared to placebo treatment during or after AS surgery, by gathering data from randomized both controlled trials (RCTs) and non-RCTs. METHODS: English and Chinese electronic databases including PubMed, Web of Science, Embase, Cochrane, CNKI, and Wan Fang database were searched to identify the relevant literature up until August 2022. The primary outcomes were intraoperative blood loss and total blood loss. The secondary outcomes included the need for transfusion, postoperative hemoglobin (Hb) level, and change in Hb level. Stata 17 was used for data analysis and the risk of bias was assessed. We followed the PRISMA checklist to ensure the quality of this article. RESULTS: Twelve studies (795 participants) were included in the meta-analysis for intraoperative blood loss during surgery. The results suggest that TXA can reduce the intraoperative blood loss of the patients (MD = -306.40ml, 95%CI = -404.04ml to -208.77ml, p < 0.001). Six studies (2027 patients) were included in the meta-analysis for total blood loss. The pooled result shows that the total blood loss of the TXA group was significantly lower than that of the control group (MD = -779.24ml, 95% CI = -1157.10ml to -410.39ml, p < 0.001). Five studies (419 patients) were included in the meta-analysis for postoperative Hb level and shows a non-significant outcome (MD = 5.09 g/l, 95%CI = 2.92 g/l to 7.25 g/l, p = 0.611). Three studies (268 patients) were included in the meta-analysis for the postoperative Hb level. There is a non-significant decrease in the TXA group (MD = -0.23 g/l, 95%CI = -0.48 g/l to 0.01 g/l, p = 0.319). Eight studies (670 patients) reported data on the need for transfusion after surgery. The overall relative risks (RR) showed a significant difference between the TXA and control group, with a lower risk of transfusion in the TXA group (RR = 0.547, 95%CI = 0.308 to 0.972, p = 0.04). CONCLUSIONS: The meta-analysis of the data reveals that TXA usage is associated with a significant reduction in intraoperative and total blood loss, a lower risk of transfusion, and a non-significant change in postoperative Hb levels in AS surgery However, it should be noted that the surgical operation situations varied across different studies. Therefore, further research is required to investigate the effects of TXA on specific subgroups of gender, operation time, and blood transfusion indicators. Overall, our study provides valuable evidence for the clinical management of AS surgery and may inform the development of practice guidelines and protocols for the use of TXA in this setting.

Anterior debridement, bone grafting and fixation for cervical spine tuberculosis: an iliac bone graft versus a structural manubrium graft.

BACKGROUND: Anterior debridement, decompression, bone grafting, and instrumentation are safe and effective techniques for patients with lower cervical spine tuberculosis. However, there is no consensus regarding the methods for using autogenous bone grafts. The purpose of this retrospective study was to compare the clinical outcomes of anterior surgical management for cervical spine tuberculosis by using an iliac bone graft versus a structural manubrium graft. METHODS: From January 2009 to September 2018, 23 patients with cervical spine tuberculosis were treated with anterior debridement, autogenous structural bone grafting and fixation at our spinal department. The patients were divided into 2 groups according to the different graft materials, namely, iliac crest bone grafts (Group A) and structural manubrium grafts (Group B). The clinical and radiographic results of the 2 groups were analyzed and compared. RESULTS: The mean duration of follow-up was 24 months. Bony fusion was achieved in all patients without failure of internal fixation. There were no significant differences between the two groups with respect to the operation time, blood loss, fusion time, neurological outcomes, or postoperative local Cobb angle (P > .05). However, the donor site complication rate in Group A was greater than that in Group B. The postoperative ambulation time in Group A was later than that in Group B. The mean visual analog scale (VAS) score for donor site pain in Group A was higher than that in Group B at 1 week after surgery (P < 0.05). However, there was no significant difference between the 2 groups at the last visit (P > .05). CONCLUSION: Both iliac bone grafts and sternal manubrium grafts can effectively reconstruct anterior column defects in anterior surgery. However, structural sternal manubrium autografts cause fewer complications associated with donor site morbidities than iliac bone grafts.

The improved bioactive n-HA/PA66 cage versus the PEEK cage in anterior cervical fusion: results from a 6-year follow-up and a case-matched study.

BACKGROUND: The nanohydroxyapatite/polyamide 66 (n-HA/PA66) cage, a bioactive nonmetal cage, is fabricated in a hollow cylindrical shape and has been widely used for decades with good clinical outcomes for anterior cervical fusion. However, there remain some radiological complications, such as a slightly high subsidence rate. To improve the clinical outcomes, the improved n-HA/PA66 cage now has been developed into a trapezoidal and wedge shape, a better biomechanical shape matching the cervical spine that is similar to that of the PEEK cage. However, there have been no long-term comparisons of the improved n-HA/PA66 cage and PEEK cage in anterior cervical reconstruction. METHODS: Fifty-eight patients who underwent single-level anterior cervical decompression and fusion (ACDF) with the improved n-HA/PA66 cage (n-HA/PA66 group) were matched with patients with the PEEK cage (PEEK group) by clinical presentation, segment, age and sex. All patients underwent a minimum of 6 years of follow-up. The radiographic parameters (cage subsidence, fusion status, cervical lordosis, and segmental sagittal alignment) and clinical parameters (10-point visual analogue scale, Neck Disability Index and Japanese Orthopedic Association scores) from patients were evaluated before surgery, immediately after surgery, and at the latest follow-up. RESULTS: The n-HA/PA66 and PEEK groups were well matched in terms of clinical presentation, segment, age, and sex at surgery. The n-HA/PA66 and PEEK cages had similar fusion rates at 6 months postoperatively (n-HA/PA66: 58.6% vs. PEEK: 51.7%, P = 0.455) and at the last follow-up (n-HA/PA66: 96.6% vs. PEEK: 93.1%, P = 0.402). The respective cage subsidence rates in the n-HA/PA66 and PEEK groups were 6.9 and 12.1% (P = 0.342). The correction of SA was similar between the groups at the final follow-up (n-HA/PA66: 4.29 ± 1.99 vs. PEEK: 3.99 ± 2.59 P = 0.464). There were no significant differences between the two groups in mean cervical lordosis, visual analogue scale scores of the neck and arm, NDI scores, JOA scores or patients' overall satisfaction at the final follow-up. CONCLUSION: After single-level ACDF, the improved n-HA/PA66 cage had similar excellent results in both radiological and clinical outcomes compared with the PEEK cage over 6 years of follow-up. According to these results, the improved n-HA/PA66 cage and the PEEK cage could be comparable for ACDF.

Postoperative proximal junctional kyphosis correlated with thoracic inlet angle in Lenke 5c adolescent idiopathic scoliosis patients following posterior surgery.

BACKGROUND: Proximal junctional kyphosis is a common complication after posterior fusion in patients with adolescent idiopathic scoliosis and is correlated with postoperative changes of thoracic kyphosis. In lenke 5c patients, higher postoperative LL and spontaneous change of TK may produce an effect on final PJK. However, no studies has been performed to evaluate the correlation of PJK with thoracocervical parameters in patients with AIS. METHODS: Data from 98 patients who underwent posterior fusion for Lenke 5C AIS with 2 years of follow-up were retrospectively reviewed. Patients in the extended fusion group underwent fusion at levels higher than upper-end vertebra + 2 (n = 38), and those in the thoracolumbar/lumbar (TL/L) fusion group underwent fusion at UEV + 2 or lower (n = 60). RESULTS: During an average follow-up of 38.1 months, 23 of 98 patients developed PJK. The extended fusion group had a higher incidence of PJK than the TL/L fusion group (14/38 vs. 9/60, respectively; P = 0.01) and a significantly greater decrease in thoracic kyphosis than the TL/L group (P < 0.01). Patients with PJK had a significantly larger preoperative thoracic inlet angle (TIA) than those without PJK (P < 0.01). Multivariate analysis showed that a greater preoperative TIA and extended fusion were associated with PJK. The Scoliosis Research Society 22-item questionnaire score did not significantly differ between the PJK and non-PJK groups. CONCLUSIONS: The preoperative TIA could be a predictor of PJK. Among patients with Lenke 5C AIS, those with a TIA of > 71° are more likely to develop PJK. Additionally, extended fusion in patients with Lenke 5C may increase the risk of PJK.

Influence of coronal-morphology of endplate and intervertebral space to cage subsidence and fusion following oblique lumbar interbody fusion.

BACKGROUND: Endplate morphology is considered to be one of the influencing factors of cage subsidence after lumbar interbody fusion (LIF). Previous radiographic evaluations on the endplate mostly used sagittal X-ray or MRI. However, there are few studies on the CT evaluation of the endplate and intervertebral space (IVS), especially the evaluation of coronal morphology and its influence on subsidence and fusion after LIF. We aimed to measure and classify the shapes of the endplate and IVS using coronal CT imaging and evaluate the radiographic and clinical outcomes of different shapes of the endplate/IVS following oblique lateral lumbar interbody fusion (OLIF). METHODS: A total of 137 patients (average age 59.1 years, including 75 males and 62 females) who underwent L4-5 OLIF combined with anterolateral fixation from June 2018 to June 2020 were included. The endplate concavity depth (ECD) was measured on the preoperative coronal CT image. According to ECD, the endplate was classified as flat (< 2 mm), shallow (2-4 mm), or deep (> 4 mm). The L4-5 IVS was further classified according to endplate type. The disc height (DH), DH changes, subsidence rate, fusion rate, and Oswestry Disability Index (ODI) in different endplate/IVS shapes were evaluated during 1-year follow up. RESULTS: The ECD of L4 inferior endplate (IEP) was significantly deeper than that of L5 superior endplate (SEP) (4.2 ± 1.1 vs 1.6 ± 0.8, P < 0.01). Four types of L4-5 IVS were identified: shallow-shallow (16, 11.7%), shallow-flat (45, 32.9%), deep-shallow (32, 23.4%), and deep-flat (44, 32.1%). A total of 45 (32.9%) cases of cage subsidence were observed. Only one (6.3%) subsidence event occurred in the shallow-shallow group, which was significantly lower than in the other three groups (19 shallow-flat, 6 deep-shallow, and 19 deep-flat) (P < 0.05). Meanwhile, the shallow-shallow group had the highest fusion rate (15, 93.8%) and the highest rate of reach minimal clinically important difference (MCID) ODI among the four types. For a single endplate, the shape of L4 IEP is the main influencing factor of the final interbody fusion rate, and the shallow shape L4 IEP facilitates fusion ( OR = 2.85, p = 0.03). On the other hand, the flat shape L5 SEP was the main risk factor to cage subsidence (OR = 4.36, p < 0.01). CONCLUSION: The L4-5 IVS is asymmetrical on coronal CT view and tends to be fornix-above and flat-down. The shallow-shallow IVS has the lowest subsidence rate and best fusion result, which is possibly because it has a relatively good degree in matching either the upper or lower interface of the cage and endplates. These findings provide a basis for the further improvements in the design of OLIF cages.