Animal Models of Internal Endplate Injury-Induced Intervertebral Disc Degeneration: A Systematic Review.

OBJECTIVE: To systematically review relevant animal models of disk degeneration induced through the endplate injury pathway and to provide suitable animal models for exploring the intrinsic mechanisms and treatment of disk degeneration. DESIGN: PubMed, Web of Science, Cochrane and other databases were searched for literature related to animal models of disk degeneration induced by the endplate injury pathway from establishment to August 2024, and key contents in the literature were screened and extracted to analyze and evaluate each type of animal model using the literature induction method. RESULTS: Fifteen animal experimental studies were finally included in the literature, which can be categorized into direct injury models and indirect injury models, of which direct injury models include transvertebral injury models and transpedicular approach injury models, and indirect injury models include endplate ischemia models and vertebral fracture-induced endplate injury models. The direct injury models have a minimum observation period of 2 months and a maximum of 32 wk. All direct injury models were successful in causing disk degeneration, and the greater the number of interventions, the greater the degree of disk degeneration caused. The observation period for the indirect injury models varied from 4 wk to 70 wk. Of the 9 studies, only one study was unsuccessful in inducing disk degeneration, and this was the first animal study in this research to attempt to intervene on the endplate to cause disk degeneration. CONCLUSION: The damage to the direct injury model is more immediate and controllable in extent and can effectively lead to disk degeneration. The indirect injury models do not directly damage the endplate structure, making it easier to observe the physiological and pathological condition of the endplate and associated structures of the disk. None of them can completely simulate the corresponding process of endplate injury-induced disk degeneration in humans, and there is no uniform clinical judgment standard for this type of model. The most appropriate animal model still needs further exploration and discovery.

Jintiange capsule may have a positive effect on pain relief and functional activity in OVCF patients with PVA: A meta-analysis of randomized control trials.

BACKGROUND: This study aims to systematically evaluate the clinical efficacy and adverse reactions associated with Jintiange capsule (JTG capsule)-assisted percutaneous vertebral augmentation (PVA) in the treatment of osteoporotic vertebral compression fracture (OVCF). METHODS: A comprehensive search was conducted across multiple databases including PubMed, Cochrane Library, EMBASE, Web of Science Database, China Biomedical Database, China VIP Network, China National Knowledge Infrastructure, Wanfang, and VIP Chinese Journal databases until June 1, 2022. Manual searches were also performed in relevant journals. Randomized controlled trials investigating the efficacy of JTG capsule-assisted PVA in the treatment of OVCF were identified and selected for inclusion. The quality of the included studies was assessed using the Cochrane risk bias assessment tool and Jadad scale. Meta-analysis was conducted using Stata MP18 software. RESULTS: A total of 138 literatures were retrieved, and 12 RCTS were finally included after screening, involving 1099 patients. Overall, the quality of the included literature was low, and all the included literatures were randomized controlled experiments, among which 9 were grouped by random number table, and 3 did not specify the random assignment plan. The total effective rate of the experimental group was higher than that of the control group (relative ratio: 1.19, 95% confidence interval: 1.11, 1.26, P = .868, I2 = 0%). The heterogeneity of visual analog score, Oswestry disability index, bone mineral density (BMD) of lumbar vertebrae, BMD of femoral neck and bone-γ-carboxyglutamic acid-containing protein was high. The reasons for the high heterogeneity were the age of patients, the follow-up time and the small sample size. There is publication bias in visual analog score, Oswestry disability index scores, and lumbar spine bone mineral density, and we believe that publication bias may be related to selective reporting of positive results by the authors and selective publication of positive results by the publishers. CONCLUSION: JTG capsule has demonstrated promising outcomes in alleviating the pain experienced by OVCF patients following PVP. Additionally, it has shown efficacy in enhancing postoperative lumbar and back function. Furthermore, JTG capsule has been associated with improvements in postoperative vertebral BMD and serum bone-γ-carboxyglutamic acid-containing protein levels. These findings suggest that JTG capsule could potentially serve as a viable adjunctive treatment option for managing osteoporosis following PVA.

Cervical Vertebra Bone Quality Score Predicts Zero-Profile Anchored Spacer Interbody Fusion Cage Subsidence after Anterior Cervical Diskectomy and Fusion: A Retrospective Study.

STUDY DESIGN: Retrospective study. OBJECTIVE: This retrospective study primary focus is to investigate the relationship between the C-VBQ score and the occurrence of postoperative zero-profile anchored spacer (ROI-C) interbody fusion cage subsidence. Additionally, we aim to evaluate the predictive efficacy of the C-VBQ scoring system for subsidence in the context of ACDF with the ROI-C. METHODS: Patients who underwent ACDF with the ROI-C cage at our hospital between January 2016 and December 2022 were included in this study. Univariate analysis and multivariate logistic regression were employed to identify independent risk factors associated with ROI-C cage subsidence after ACDF. Pearson correlation analysis was utilized to assess the correlation between the C-VBQ score and the height of ROI-C cage subsidence. RESULTS: A total of 102 patients underwent ACDF with ROI-C in our hospital were included in this study. Univariate analysis showed that age (P = 0.021) and C-VBQ score (P < 0.001) were the influencing factors of cage subsidence. Pearson correlation analysis showed that there was a significant positive correlation between the subsidence height of ROI-C cage and C-VBQ (r = 0.55, P < 0.01). Multivariate binary logistic regression analysis showed that C-VBQ score was the only variable that could significantly predict the subsidence of ROI-C cage after ACDF. Higher C-VBQ score was significantly associated with cage subsidence (P < 0.001).The AUC was 0.89, and the cutoff value for C-VBQ was 2.70. CONCLUSION: The findings indicate a significant correlation between a higher C-VBQ score before surgery and ROI-C cage subsidence after ACDF. The preoperative assessment of C-VBQ proves valuable for clinicians, enabling them to identify patients with low bone mineral density and predict the risk of zero-profile anchored spacer interbody fusion cage subsidence following ACDF.

Prediction of Screw Loosening After Dynamic Pedicle Screw Fixation With Lumbar Polyetheretherketone Rods Using Magnetic Resonance Imaging-Based Vertebral Bone Quality Score.

OBJECTIVE: To investigate the correlation between magnetic resonance imaging-based vertebral bone quality (VBQ) score and screw loosening after dynamic pedicle screw fixation with polyetheretherketone (PEEK) rods, and evaluate its predictive value. METHODS: A retrospective analysis was conducted on the patients who underwent dynamic pedicle screw fixation with PEEK rods from March 2017 to June 2022. Data on age, sex, body mass index, hypertension, diabetes, hyperlipidemia history, long-term smoking, alcohol consumption, VBQ score, L1-4 average Hounsfield unit (HU) value, surgical fixation length, and the lowest instrumented vertebra were collected. Logistic regression analysis was employed to assess the relationship between VBQ score and pedicle screw loosening (PSL). RESULTS: A total of 24 patients experienced PSL after surgery (20.5%). PSL group and non-PSL group showed statistical differences in age, number of fixed segments, fixation to the sacrum, L1-4 average HU value, and VBQ score (p < 0.05). The VBQ score in the PSL group was higher than that in the non-PSL group (3.56 ± 0.45 vs. 2.77 ± 0.31, p < 0.001). In logistic regression analysis, VBQ score (odds ratio, 3.425; 95% confidence interval, 1.552-8.279) were identified as independent risk factors for screw loosening. The area under the receiver operating characteristic curve for VBQ score predicting PSL was 0.819 (p < 0.05), with the optimal threshold of 3.15 (sensitivity, 83.1%; specificity, 80.5%). CONCLUSION: The VBQ score can independently predict postoperative screw loosening in patients undergoing lumbar dynamic pedicle screw fixation with PEEK rods, and its predictive value is comparable to HU value.

Study on the consistency between CT hounsfield units and MRI evaluation of preoperative cervical paraspinal muscular fat infiltration in patients undergoing ACDF.

OBJECTIVE: To explore the feasibility of applying CT Hounsfield Units (HUs) for the assessment of preoperative paraspinal muscle fat infiltration (FI) in different segments in patients who underwent anterior cervical discectomy and fusion (ACDF). To compare the consistency of preoperative paraspinal muscle FI evaluations using MRI and those via CT HUs in patients who underwent ACDF surgery. METHODS: Ninety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson's test or Sperman's test was used to analyze the correlation. RESULTS: On MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment. CONCLUSION: Patients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine.

Clinical study on freehand of bicortical sacral screw fixation with the assistance of torque measurement device.

BACKGROUND: Sacral screw loosening is a typical complication after internal fixation surgery through the vertebral arch system. Bicortical fixation can successfully prevent screw loosening, and how improving the rate of bicortical fixation is a challenging clinical investigation. OBJECTIVE: To investigate the feasibility of improving the double corticality of sacral screws and the optimal fixation depth to achieve double cortical fixation by combining the torque measurement method with bare hands. METHODS: Ninety-seven cases of posterior lumbar internal fixation with pedicle root system were included in this study. Based on the tactile feedback of the surgeon indicating the expected penetration of the screw into the contralateral cortex of the sacrum, the screws were further rotated by 180°, 360°, or 720°, categorized into the bicortical 180° group, bicortical 360° group, and bicortical 720° group, respectively. Intraoperatively, the torque during screw insertion was recorded. Postoperatively, the rate of double-cortex engagement was evaluated at 7 days, and screw loosening was assessed at 1 year follow-up. RESULTS: The bicortical rates of the 180° group, 360° group, and 720° group were 66.13%, 91.18% and 93.75%, respectively. There were statistically significant differences between the 180° group and both the 360° and 720° groups (P < 0.05). However, there was no statistically significant difference between the 360° group and the 720° group (P > 0.05).The rates of loosening of sacral screws in the 180° group, 360° group, and 720° group were 20.97%, 7.35% and 7.81%, respectively. There were statistically significant differences between the 180° group and both the 360° and 720° groups (P < 0.05). However, there was no statistically significant difference between the 360° group and the 720° group (P > 0.05). The bicortical 360° group achieved a relatively satisfactory rate of dual cortical purchase while maintaining a lower rate of screw loosening. CONCLUSION: Manual insertion of sacral screws with the assistance of a torque measurement device can achieve a relatively satisfactory dual cortical purchase rate while reducing patient hospitalization costs.

Correlation between axial symptoms and cervical sagittal alignment parameters in patients with two-level or three-level cervical spondylotic myelopathy: anterior cervcial discectomy and fusion versus hybird surgery.

OBJECTIVE: To comparatively analyze the correlation between axial symptoms (AS) and cervical sagittal alignment parameters after anterior cervical discectomy and fusion (ACDF) and hybrid surgery (HS). METHODS: From January 2018 to June 2023, 74 patients who underwent ACDF (n = 36) or HS (n = 38) for two-level or three-level cervical spondylotic myelopathy were retrospectively analyzed. The Visual Analogue Scale (VAS), Japanese Orthopedic Association (JOA), Neck Disability Index (NDI) were recorded to assess clinical outcomes. Cervical sagittal alignment parameters (Cobb's angle C2-7, C7 slope [C7S], and C2-7 sagittal vertical axis [C2-7 SVA]) were measured preoperatively, 3 days postoperatively, and at the last follow-up. The range of motion (ROM) of C2-7 and ROM of surgical segment were measured. The occurrence of AS was observed at the last follow-up. Logistic regression was used to analyze the correlation between postoperative AS and cervical sagittal alignment parameters. RESULTS: Both in ACDF group and HS group, VAS, JOA and NDI scores showed significant improvements at 3-day postoperation and at the last follow-up (P < 0.05). However, there was no significant difference between the two groups (P > 0.05). The Cobb's angle C2-7 and C7S were significantly increased at 3 days postoperation compared with pre-operatively in both groups (P < 0.05). C2-7SVA was increased in both groups 3 days after surgery compared with pre-operatively, but there was no significant difference (P > 0.05). At the last follow-up, the ROM of C2-7 in ACDF group was significantly smaller than HS group (P < 0.05). The prevalence of postoperative AS in the ACDF group and HS group was 41.7 and 18.4%, respectively, with statistical difference between the two groups (P < 0.05). When simple Logistic regression analysis was used, the last Cobb's angle C2-7 (ß = -0.088), the last C2-7SVA (ß = 0.099) in ACDF group and the last C2-7SVA (ß = 0.222) in HS group were all correlated with the occurrence of postoperative AS. When multiple Logistic regression analysis was used, only the last C2-7SVA (ß = 0.181) in the HS group was positively correlated with the occurrence of postoperative AS. CONCLUSIONS: Both ACDF and HS can achieve satisfied clinical outcomes. ACDF and HS can improve cervical sagittal balance to a certain extent, and HS is superior to ACDF in maintaining ROM. The decrease of the last Cobb's angle C2-7 and the increase of the last C2-7SVA may be related to the occurrence of AS after ACDF. The increase of the last C2-7SVA was an independent risk factor for the occurrence of AS after HS.

New evidence on the controversy over the correlation between vertebral osteoporosis and intervertebral disc degeneration: a systematic review of relevant animal studies.

OBJECTIVE: The effect of vertebral osteoporosis on disc degeneration remains controversial. The aim of this study was to conduct a systematic review and meta-analysis of relevant animal studies to shed more light on the effects and mechanisms of vertebral osteoporosis on disc degeneration and to promote the resolution of the controversy. METHODS: The PubMed, Cochrane Library, and Embase databases were searched for studies that met the inclusion criteria. Basic information and data were extracted from the included studies and data were analyzed using STATA 15.1 software. This study was registered on INPLASY with the registration number INPLASY202370099 and https://doi.org/10.37766/inplasy2023.7.0099 . RESULTS: A total of 13 studies were included in our study. Both animals, rats and mice, were covered. Meta-analysis results showed in disc height index (DHI) (P < 0.001), histological score (P < 0.001), number of osteoblasts in the endplate (P = 0.043), number of osteoclasts in the endplate (P < 0.001), type I collagen (P < 0.001), type II collagen (P < 0.001), aggrecan (P < 0.001), recombinant a disintegrin and metalloproteinase with thrombospondin-4 (ADAMTS-4) (P < 0.001), matrix metalloproteinase-1 (MMP-1) (P < 0.001), MMP-3 (P < 0.001), MMP-13 (P < 0.001), the difference between the osteoporosis group and the control group was statistically significant. In terms of disc volume, the difference between the osteoporosis group and the control group was not statistically significant (P = 0.459). CONCLUSION: Our study shows that vertebral osteoporosis may exacerbate disc degeneration. Abnormal bone remodeling caused by vertebral osteoporosis disrupts the structural integrity of the endplate, leading to impaired nutrient supply to the disc, increased expression of catabolic factors, and decreased levels of type II collagen and aggrecan may be one of the potential mechanisms.