Characteristics and evaluation of C1 posterior arch variation for transpedicular screw placement between patients with and without basilar invagination.

BACKGROUND: C1 transpedicular screw (C1TS) placement provided satisfactory pullout resistance and 3D stability, but its application might be limited in patients with basilar invagination (BI) due to the high incidences of the atlas anomaly and vertebral artery (VA) variation. However, no study has explored the classifications of C1 posterior arch variations and investigated their indications and ideal insertion trajectories for C1TS in BI. PURPOSE: To investigate the bony and surrounding arterial characteristics of the atlas, classify posterior arch variations, identify indications for C1TS, evaluate ideal insertion trajectories for C1TS in BI patients without atlas occipitalization (AO), and compare them with those without BI and AO as control. METHODS: A total of 130 non-AO patients with and without BI (52 patients and 78 patients, respectively) from two medical centers were included at a 1:1.5 ratio. The posterior arch variations were assessed using a modified C1 morphological classification. Comparisons regarding the bony and surrounding arterial characteristics, morphological classification distributions, and ideal insertion trajectories between BI and control groups were performed. The subgroup analyses based on different morphological classifications were also conducted. In addition, the factors possibly affecting the insertion parameters were investigated using multiple linear regression analyses. RESULTS: The BI group was associated with significantly smaller lateral mass height and width, sagittal length of posterior arch, pedicle height, vertical height of posterior arch, and distance between VA and VA groove (VAG) than control group. Four types of posterior arch variations with indications for different screw placement techniques were classified; Classifications I and II were suitable for C1TS. The BI cohort showed a significantly lower rate of Classification I than the control cohort. In the BI group, the subgroup of Classification I had significantly larger distance between the insertion point (IP) and inferior aspect of the posterior arch. In addition, it had the narrowest width along ideal screw trajectory, but a significantly more lateral ideal mediolateral angle than the subgroup of Classification II. Multiple linear regression indicated that the cephalad angle was significantly associated with the diagnosis of BI (B = 3.708, P < 0.001) and sagittal diameter of C1 (B = 3.417, P = 0.027); the ideal mediolateral angle was significantly associated with BMI (B = 0.264, P = 0.031), sagittal diameter of C1 (B = - 4.559, P = 0.002), and pedicle height (B = - 2.317, P < 0.001); the distance between the IP and inferior aspects of posterior arch was significantly associated with age (B = - 0.002, P = 0.035), BMI (B = - 0.007, P = 0.028), sagittal length of posterior arch (B = - 0.187, P = 0.032), pedicle height (B = - 0.392, P < 0.001), and middle and lower parts of posterior arch (B = 0.862, P < 0.001). CONCLUSION: The incidence of posterior arch variation in BI patients without AO was remarkably higher than that in control patients. The insertion parameters of posterior screws were different between the morphological classification types in BI and control groups. The distance between VA V3 segments and VAG in BI cohort was substantially smaller than that in control cohort. Preoperative individual 3D computed tomography (CT), CT angiography and intraoperative navigation are recommended for BI patients receiving posterior screw placement.

Pericytes Regulate Cerebral Perfusion through VEGFR1 in Ischemic Stroke.

Neurons in the penumbra (the area surrounding ischemic tissue that consists of still viable tissue but with reduced blood flow and oxygen transport) may be rescued following stroke if adequate perfusion is restored in time. It has been speculated that post-stroke angiogenesis in the penumbra can reduce damage caused by ischemia. However, the mechanism for neovasculature formation in the brain remains unclear and vascular-targeted therapies for brain ischemia remain suboptimal. Here, we show that VEGFR1 was highly upregulated in pericytes after stroke. Knockdown of VEGFR1 in pericytes led to increased infarct area and compromised post-ischemia vessel formation. Furthermore, in vitro studies confirmed a critical role for pericyte-derived VEGFR1 in both endothelial tube formation and pericyte migration. Interestingly, our results show that pericyte-derived VEGFR1 has opposite effects on Akt activity in endothelial cells and pericytes. Collectively, these results indicate that pericyte-specific expression of VEGFR1 modulates ischemia-induced vessel formation and vascular integrity in the brain.

Comparison of robotic or computer-assisted navigation versus fluoroscopic freehand techniques in the accuracy of posterior cervical screw placement during cervical spine surgery: a meta-analysis.

OBJECTIVE: Robot guidance (RG) and computer-assisted navigation (CAN) have been increasingly utilized for posterior cervical screw placement in cervical spine surgery, and cervical screw malposition may contribute to catastrophic complications. However, the superiority of the navigation using RG or CAN compared with conventional freehand (FH) techniques remains controversial, and no meta-analysis comparing the two methods in cervical spine surgery has been performed. METHODS: The PubMed, Embase, Web of Science, Cochrane, China National Knowledge Infrastructure, and Wanfang databases were searched for eligible literature. Studies reporting the primary outcomes of the accuracy of cervical screw placement using RG or CAN compared with FH techniques were included. Bias was evaluated using the Cochrane risk of bias criteria and the Newcastle-Ottawa Scale. The outcomes were evaluated in terms of odds ratio or standardized mean difference and corresponding 95% confidence interval. RESULTS: One randomized controlled trial and 18 comparative cohort studies published between 2012 and 2023 consisting of 946 patients and 4163 cervical screws were included in this meta-analysis. The RG and CAN techniques were associated with a substantially higher rate of optimal and clinically acceptable cervical screw accuracy than FH techniques. Furthermore, compared with the FH group, the navigation group showed fewer postoperative adverse events, less blood loss, shorter hospital lengths of stay, and lower postoperative Neck Disability Index scores. However, the navigation and FH groups had equivalent intraoperative times and postoperative visual analog scale and Japanese Orthopaedic Association scores at the final follow-up. CONCLUSIONS: Both RG and CAN are superior to FH techniques in terms of the accuracy of cervical screw placement. Navigation techniques, including RG and CAN methods, are accurate, safe, and feasible in cervical spine surgery.

Comparative effectiveness of nonpharmacological interventions in reducing psychological symptoms among patients with chronic low back pain.

OBJECTIVES: Chronic low back pain (CLBP) can seriously impair the quality of life of patients and has a remarkable comorbidity with psychological symptoms, which, in turn, can further exacerbate the symptoms of CLBP. Psychological treatments are critical and nonnegligent for the management of CLBP, and thus, should attract sufficient attention. However, current evidence does not suggest the superiority and effectiveness of nonpharmacological interventions in reducing psychological symptoms among patients with CLBP.Thus, this study was designed to compare the effectiveness of nonpharmacological interventions for depression, anxiety, and mental health among patients with CLBP and to recommend preferred strategies for attenuating psychological symptoms in clinical practice. METHODS: In this systematic review and network meta-analysis (NMA), PubMed, Embase Database, Web of Science, and Cochrane Library were searched from database inception until March 2022. Randomized clinical trials (RCTs) that compare different nonpharmacological interventions for depression, anxiety, and mental health among patients with CLBP were eligible. The Preferred Reporting Items for Systematic Reviews and Meta-analyses statement was used. Four reviewers in pairs and divided into two groups independently performed literature selection, data extraction, and risk of bias, and certainty of evidence assessments. This NMA was conducted with a random effects model under a frequentist framework. The major outcomes were depression, anxiety, and mental health presented as the standardized mean difference (SMD) with the corresponding 95% CI. RESULTS: A total of 66 RCTs that randomized 4806 patients with CLBP met the inclusion criteria. The quality of evidence was typically low or some risks of bias (47 out of 66 trials, 71.3%), and the precision of summary estimates for effectiveness varied substantially. In addition, 7 categories of interventions with 26 specific treatments were evaluated. For depression, mind body therapy (pooled SMD = -1.20, 95% CI: -1.63 to -0.78), biopsychosocial approach (pooled SMD = -0.41, 95% CI: -0.70 to -0.12), and physical therapy (pooled SMD = -0.26, 95% CI: -0.50 to -0.02) exhibited remarkable effectiveness in reducing depression compared with the control group. For managing anxiety, mind body therapy (pooled SMD = -1.35, 95% CI: -1.90 to -0.80), multicomponent intervention (pooled SMD = -0.47, 95% CI: -0.88 to -0.06), and a biopsychosocial approach (pooled SMD = -0.46, 95% CI: -0.79 to -0.14) were substantially superior to the control group. For improving mental health, multicomponent intervention (pooled SMD = 0.77, 95% CI: 0.14 to 1.39), exercise (pooled SMD = 0.60, 95% CI: 0.08 to 1.11), and physical therapy (pooled SMD = 0.47, 95% CI: 0.02-0.92) demonstrated statistically substantial effectiveness compared with the control group. The rank probability indicated that mind body therapy achieved the highest effectiveness in reducing depression and anxiety among patients with CLBP. Besides, the combined results should be interpreted cautiously based on the results of analyses evaluating the inconsistency and certainty of the evidence. CONCLUSION: This systemic review and NMA suggested that nonpharmacological interventions show promise for reducing psychological symptoms among patients with CLBP. In particular, mind body therapy and a biopsychosocial approach show considerable promise, and mind body therapy can be considered a priority choice in reducing depression and anxiety. These findings can aid clinicians in assessing the potential risks and benefits of available treatments for CLBP comorbidity with psychological symptoms and provide evidence for selecting interventions in clinical practice. More RCTs involving different interventions with rigorous methodology and an adequate sample size should be conducted in future research.

Prognostic Structural Neural Markers of MRI in Response to Mechanical Thrombectomy for Basilar Artery Occlusion.

Objective: Mechanical thrombectomy (MT) has been an effective first-line therapeutic strategy for ischemic stroke. With impairment characteristics separating it from anterior circulation stroke, we aimed to explore prognostic structural neural markers for basilar artery occlusion (BAO) after MT. Methods: Fifty-four BAO patients with multi-modal magnetic resonance imaging at admission from the multicenter real-world designed BASILAR research were enrolled in this study. Features including volumes for cortical structures and subcortical regions, locations and volumes of infarctions, and white matter hyperintensity (WMH) volumes were recorded from all individuals. The impact features were identified using ANCOVA and logistic analysis. Another cohort (n = 21) was further recruited to verify the prognostic roles of screened prognostic structures. Results: For the primary clinical outcome, decreased brainstem volume and total infarction volumes from mesencephalon and midbrain were significantly related to reduced 90-day modified Rankin score (mRS) after MT treatment. WMH volume, WMH grade, average cortex thickness, white matter volume, and gray matter volume did not exhibit a remarkable relationship with the prognosis of BAO. The increased left caudate volume was obviously associated with early symptomatic recovery after MT. The prognostic role of the ratio of pons and midbrain infarct volume in brainstem was further confirmed in another cohort with area under the curve (AUC) = 0.77. Conclusions: This study was the first to provide comprehensive structural markers for the prognostic evaluation of BAO. The fully automatic and semiautomatic segmentation approaches in our study supported that the proportion of mesencephalon and midbrain infarct volume in brainstem was a crucial prognostic structural neural marker for BAO.