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Objective. This study's primary objective was to examine the risk of recall for novel spine devices over time. Secondarily, we sought to analyze interbody fusion and vertebral body replacement (VBR) devices (corpectomy cages) as a risk factor for recall. Background. The recall risk of a novel spine device over time has not been reported. In addition, FDA regulations were lowered for interbody fusion devices to enter the market in 2007. As well, VBR implants were recently approved by the FDA for use in the cervical spine in 2015. Materials and Methods. Spine devices cleared between January 1, 2008 and December 31, 2018 were identified from the FDA's 510(k) database. All recall data were collected from the database in January 2021 to provide a 2-year minimum follow-up for a recall to occur. Product labels were used to classify interbody fusion and VBR devices. Cumulative incidence function was conducted to compare the overall risk of recall for FDA-cleared spine devices, and the hazard ratio determined for VBR and all other devices versus interbody implants during the study period. Results. A total of 2384 spine devices were cleared through 510 (k) in the study period. The hazard of recall at 5 years was 5.3% (95% CI: 4.4%-6.2%) and 6.5% (95% CI: 5.4%-7.7%) at 10 years. No significant difference in recall risk was identified for interbody fusion and VBR devices. Conclusion. The risk of recall at 5 and 10 years of a novel spine device is about half the 12% rate reported for orthopedic devices in general. Despite lowered FDA regulations for interbody fusion devices and recent approval for VBR device use in the cervical spine, no increased risk of recall was detected. Further research is necessary to explain the reason for the lower risk of recall with spine devices. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to quantify and evaluate morphology of intervertebral space between neighboring cervical units using radiographic imaging indices, to help spine surgeons when performing anterior cervical discectomy and fusion (ACDF) surgery on the Chinese population. Methods: The background and imaging parameters of the subjects were assessed. Cervical lateral radiographs were employed to measure the intervertebral height (IH), intervertebral height index (IHI), and segmental lordosis (SL). Endplate parameters measurements were conducted on sagittal T2-weighted magnetic resonance imaging (MRI), including endplate sagittal diameter (ESD), and endplate concavity depth (ECD). All individuals were divided into three age groups: individuals aged 20–35 were in group A, individuals aged 36–50 were in group B, and individuals aged over 50 were in group C. A comparison of the variables was conducted among the three groups. Additionally, these radiographic parameters were also compared between males and females. Results: A total of 102 individuals were included in this study. IH was greater at C6/7 than those at other segmental levels (p < 0.001). The largest SL values were found at C6/7, while the least were found at C3/4. The superior ESD (ESDs) and ECD (ECDs) of the intervertebral space were significantly greater than those of the inferior endplates (p < 0.05). The ESD and ECD values were the largest at C6/7, while the least at C3/4. Additionally, age and gender had an influence on several parameters. IH was significantly lower in group A compared to group B (p < 0.05) and group C (p < 0.05) from C3/4 level to C6/7 level. ECDs were lower in group A compared to group B (p < 0.05) and group C (p < 0.05) at each level. IH and ESD in males were generally significantly greater than those in females at all levels (p < 0.05). Conclusion: The current study found that C6/7 had the greatest IH, SL, ESD, and ECD values in asymptomatic Chinese. SL gradually increased from C3/4 to C6/7 levels. IH and ECD were significantly associated with age. Males had greater IH and ESD values than females. These findings provide baseline information for planning for selection of anterior screws and intervertebral implants. [ABSTRACT FROM AUTHOR]

Introduction The cervical spine, pivotal for mobility and overall body function, can be affected by cervical spondylosis, a major contributor to neural disorders. Prevalent in both general and military populations, especially among pilots, cervical spondylosis induces pain and limits spinal capabilities. Anterior Cervical Discectomy and Fusion (ACDF) surgery, proposed by Cloward in the 1950s, is a promising solution for restoring natural cervical curvature. The study objective was to investigate the impacts of ACDF implant design on postsurgical cervical biomechanics and neurorehabilitation outcomes by utilizing a biofield head-neck finite element (FE) platform that can facilitate scenario-specific perturbations of neck muscle activations. This study addresses the critical need to enhance computational models, specifically FE modeling, for ACDF implant design. Materials and Methods We utilized a validated head-neck FE model to investigate spine–implant biomechanical interactions. An S-shaped dynamic cage incorporating titanium (Ti) and polyetheretherketone (PEEK) materials was modeled at the C4/C5 level. The loading conditions were carefully designed to mimic helmet-to-helmet impact in American football, providing a realistic and challenging scenario. The analysis included intervertebral joint motion, disk pressure, and implant von Mises stress. Results The PEEK implant demonstrated an increased motion in flexion and lateral bending at the contiguous spinal (C4/C5) level. In flexion, the Ti implant showed a modest 5% difference under 0% activation conditions, while PEEK exhibited a more substantial 14% difference. In bending, PEEK showed a 24% difference under 0% activation conditions, contrasting with Ti's 17%. The inclusion of the head resulted in an average increase of 18% in neck angle and 14% in C4/C5 angle. Disk pressure was influenced by implant material, muscle activation level, and the presence of the head. Polyetheretherketone exhibited lower stress values at all intervertebral disc levels, with a significant effect at the C6/C7 levels. Muscle activation level significantly influenced disk stress at all levels, with higher activation yielding higher stress. Titanium implant consistently showed higher disk stress values than PEEK, with an orders-of-magnitude difference in von Mises stress. Excluding the head significantly affected disk and implant stress, emphasizing its importance in accurate implant performance simulation. Conclusions This study emphasized the use of a biofidelic head-neck model to assess ACDF implant designs. Our results indicated that including neck muscles and head structures improves biomechanical outcome measures. Furthermore, unlike Ti implants, our findings showed that PEEK implants maintain neck motion at the affected level and reduce disk stresses. Practitioners can use this information to enhance postsurgery outcomes and reduce the likelihood of secondary surgeries. Therefore, this study makes an important contribution to computational biomechanics and implant design domains by advancing computational modeling and theoretical knowledge on ACDF–spine interaction dynamics. [ABSTRACT FROM AUTHOR]

Radiologists manually interpret magnetic resonance imaging (MRI) scans for the detection of intervertebral cervical disc degeneration, which are often obtained in a primary care or emergency hospital context. The ability of computer models to work with pathological findings and aid in the first interpretation of medical imaging tests is widely acknowledged. Deep learning methods, which are commonly employed today in the diagnosis or detection of many diseases, show great promise in this area. For the detection and segmentation of intervertebral cervical disc intensity, we propose a Mask‐RCNN‐based deep learning algorithm in this study. The provided approach begins by creating an original dataset using MRI scans that were collected from Yozgat Bozok University. The senior radiologist labels the data, and three classes of intensity are chosen for the classification (low, intermediate, and high). Two alternative network backbones are used in the study, and as a consequence of the training for the Mask R‐CNN algorithm, 98.14% and 96.72% mean average precision (mAP) values are obtained with the ResNet50 and ResNet101 architectures, respectively. Utilizing the five‐fold cross‐validation approach, the study is conducted. This study also applied the Faster R‐CNN method, achieving a mAP value of 85.2%. According to the author's knowledge, no study has yet been conducted to apply deep learning algorithms to detect intervertebral cervical disc intensity in a patient population with cervical intervertebral disc degeneration. By ensuring accurate MRI image interpretation and effectively supplying supplementary diagnostic information to provide accuracy and consistency in radiological diagnosis, the proposed method is proving to be a highly useful tool for radiologists. [ABSTRACT FROM AUTHOR]

(1) Background: The kinematic characteristics of disc prosthesis undergoing complex motion are not well understood. Therefore, examining complex motion may provide an improved understanding of the post-operative behavior of spinal implants. (2) Methods: The aim of this study was to develop kinematic tests that simulate multiplanar motion and combined rotational–translational motion in a disc prosthesis. In this context, five generic zirconia-toughened alumina (BIOLOX®delta, CeramTec, Germany) ball and socket samples were tested in a 6 DOF spine simulator under displacement control with an axial compressive force of 100 N in five motion modes: (1) flexion–extension (FE = ± 7.5°), (2) lateral bending (LB = ± 6°), (3) combined FE-LB (4) combined FE and anteroposterior translation (AP = 3 mm), and (5) combined LB and lateral motion (3 mm). For combined rotational–translational motion, two scenarios were analyzed: excessive translational movement after sample rotation (scenario 1) and excessive translational movement during rotation (scenario 2). (3) Results: For combined FE-LB, the resultant forces and moments were higher compared to the unidirectional motion modes. For combined rotational–translational motion (scenario 1), subluxation occurred at FE = 7.5° with an incremental increase in AP translation = 1.49 ± 0.18 mm, and LB = 6° with an incremental increase of lateral translation = 2.22 ± 0.16 mm. At the subluxation point, the incremental increase in AP force and lateral force were 30.4 ± 3.14 N and 40.8 ± 2.56 N in FE and LB, respectively, compared to the forces at the same angles during unidirectional motion. For scenario 2, subluxation occurred at FE = 4.93° with an incremental increase in AP translation = 1.75 mm, and LB = 4.52° with an incremental increase in lateral translation = 1.99 mm. At the subluxation point, the incremental increase in AP force and lateral force were 39.17 N and 38.94 N in FE and LB, respectively, compared to the forces in the same angles during the unidirectional motion. (4) Conclusions: The new test protocols improved the understanding of in vivo-like behavior from in vitro testing. Simultaneous translation–rotation motion was shown to provoke subluxation at lower motion extents. Following further validation of the proposed complex motion testing, these new methods can be applied future development and characterization of spinal motion-preserving implants. [ABSTRACT FROM AUTHOR]

When conducting spine-related diagnosis and surgery, the three-dimensional (3D) upright posture of the spine under natural weight bearing is of significant clinical value for physicians to analyze the force on the spine. However, existing medical imaging technologies cannot meet current requirements of medical service. On the one hand, the mainstream 3D volumetric imaging modalities (e.g. CT and MRI) require patients to lie down during the imaging process. On the other hand, the imaging modalities conducted in an upright posture (e.g. radiograph) can only realize 2D projections, which lose the valid information of spinal anatomy and curvature. Developments of deep learning-based 3D reconstruction methods bring potential to overcome the limitations of the existing medical imaging technologies. To deal with the limitations of current medical imaging technologies as is described above, in this paper, we propose a novel deep learning framework, ReVerteR, which can realize automatic 3D Reconstruction of Vertebrae from orthogonal bi-planar Radiographs. With the utilization of self-attention mechanism and specially designed loss function combining Dice, Hausdorff, Focal, and MSE, ReVerteR can alleviate the sample-imbalance problem during the reconstruction process and realize the fusion of the centroid annotation and the focused vertebra. Furthermore, aiming at automatic and customized 3D spinal reconstruction in real-world scenarios, we extend ReVerteR to a clinical deployment-oriented framework, and develop an interactive interface with all functions in the framework integrated so as to enhance human–computer interaction during clinical decision-making. Extensive experiments and visualization conducted on our constructed datasets based on two benchmark datasets of spinal CT, VerSe 2019 and VerSe 2020, demonstrate the effectiveness of our proposed ReVerteR. In this paper, we propose an automatic 3D reconstruction method of vertebrae based on orthogonal bi-planar radiographs. With the 3D upright posture of the spine under natural weight bearing effectively constructed, our proposed method is expected to better support doctors make clinical decision during spine-related diagnosis and surgery. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the safety and efficacy of a novel Poly-Ether-Ether-Ketone (PEEK) expandable vertebral body replacement (VBR) for anterior cervico-thoracic vertebral column reconstruction in patients with metastatic, traumatic, or degenerative diseases. Radiographic and clinical outcomes, as well as complication rates, were analyzed in a retrospective analysis of 28 patients (61 ± 13 years; 64% female) who underwent an anterior cervical corpectomy and fusion (ACCF) with the Expandable Corpectomy Device (ECD) from DePuy/Synthes (2011–2020). Correction of the bisegmental kyphotic angle (BKA) was chosen as the primary outcome. Bony fusion, loss of device height, and implant subsidence were evaluated additionally. Clinical outcome was assessed using Odom's criteria, the numerical pain rating scale (NRS), the American Spinal Injury Association Impairment Scale (AIS), and the Karnofsky Performance Status Scale (KPSS). Our study found a significant improvement in the BKA (12.3° ± 9.6°; p = 0.0002) at the last follow-up with no statistically relevant loss of device height (p = 0.96) or implant subsidence (p = 0.99). Successful bony fusion was observed in all patients. The KPSS significantly improved in patients with a tumorous disease at the time of discharge (p = 0.0009), and the sensation of pain showed significant improvement at six months post-operatively and at the final follow-up (p = 0.004; p = 0.021). However, four patients needed further secondary posterior stabilization, and one ECD was explanted due to a severe surgical site infection after an accidental esophageal lesion. In conclusion, the ECD proofed the radiographic stability for the anterior column reconstruction of the cervico-thoracic spine with significantly improved clinical outcome. [ABSTRACT FROM AUTHOR]

Purpose: Hybrid cervical spine surgery (HS) is a novel surgical strategy wherein an artificial disc replacement is done with a cervical fusion nearby with a stand-alone titanium cage to combine the advantages in both procedures. The aim of this study was to evaluate interactions of these devices within the same patient, and to analyze, if the different goal of each implant is accomplished. Methods: Thirty-six patients were treated surgically within a non-randomized retrospective study framework with HS. Patients were examined preoperatively followed by clinical and radiological examination at least one year postoperative. Clinical outcome was detected with NDI, VAS arm/neck, pain self-assessment questionnaires and subjective patient satisfaction. Radiological assessments included RoM, segmental lordosis, cervical lordosis of C2-C7, subsidence, ap-migration and heterotopic ossifications (HO) at the cTDR levels. Results: Statistically significant improvement of all clinical scores was observed (NDI 37.5 to 5.76; VASarm 6.41 to 0.69; VASneck 6.78 to 1.48). Adequate RoM was achieved at cTDR levels. RoM in the ACDF levels was reduced statistically significant (p < 0.001), and solid fusion (> 2°) was achieved in all evaluated fusion level. Global lordosis (C2-C7) increased statistically significant (2.4° to 8.1°). Subsidence and HO at the cTDR levels did not occur. Conclusions: HS results in preservation of the segmental motion in the cTDR and fast and solid fusion in the cage cohort simultaneously. Patient safety was proven. In carefully selected cases, HS is a safe and viable treatment option by choosing the right "philosophy" level per level. [ABSTRACT FROM AUTHOR]

Objective: Cervical hybrid surgery optimizes the use of cervical disc arthroplasty (CDA) and zero-profile (ZOP) devices in anterior cervical discectomy and fusion (ACDF) but lacks uniform combination and biomechanical standards, especially in revision surgery (RS). This study aimed to investigate the biomechanical characteristics of adjacent segments of the different hybrid RS constructs in ACDF RS. Methods: An intact 3-dimensional finite element model generated a normal cervical spine (C2–T1). This model was modified to the primary C5–6 ACDF model. Three RS models were created to treat C4–5 adjacent segment degeneration through implanting cages plus plates (Cage-Cage), ZOP devices (ZOP-Cage), or Bryan discs (CDA-Cage). A 1.0-Nm moment was applied to the primary C5–6 ACDF model to generate total C2–T1 range of motions (ROMs). Subsequently, a displacement load was applied to all RS models to match the total C2–T1 ROMs of the primary ACDF model. Results: The ZOP-Cage model showed lower biomechanical responses including ROM, intradiscal pressure, maximum von Mises stress in discs, and facet joint force in adjacent segments compared to the Cage-Cage model. The CDA-Cage model exhibited the lowest biomechanical responses and ROM ratio at adjacent segments among all RS models, closely approached or lower than those in the primary ACDF model in most motion directions. Additionally, the maximum von Mises stress on the C3–4 and C6–7 discs increased in the Cage-Cage and ZOP-Cage models but decreased in the CDA-Cage model when compared to the primary ACDF model. Conclusion: The CDA-Cage construct had the lowest biomechanical responses with minimal kinematic change of adjacent segments. ZOP-Cage is the next best choice, especially if CDA is not suitable. This study provides a biomechanical reference for clinical hybrid RS decision-making to reduce the risk of ASD recurrence. [ABSTRACT FROM AUTHOR]

A virtual reality-based lumbar rehabilitation training system is designed to address the increasing number of patients with low back pain (LBP) year by year. Attitude sensors are used to track lower back movement. In order to improve the effect of rehabilitation training, several virtual rehabilitation training games and assessment scenes are designed based on the Unity3D engine to complete different tasks from simple to complex. The goal is to increase patients' interest in rehabilitation training. The experimental results verify the accuracy of rehabilitation data acquisition, real-time interactive communication, and the smooth operation of rehabilitation scenes. [ABSTRACT FROM AUTHOR]

There has been a recent uptake in the use of polyether-ether-ketone (PEEK), which is an organic thermoplastic polymer, in the manufacturing of various medical devices, implants, and equipment. Finding the best time and procedure for PEEK after sulfonation is the goal of this research. A total of 30 PEEK discs were sulfonated in this study by immersing them in concentrated (H2SO4) sulfuric acid for various durations and subsequently treated using various post-treatment techniques. Five experiments were carried out, aimed studying the effect of immersion time (5 s–2 min). The methods used as post-treatment were hydrothermal treatment, immersion in NaOH, and washing with acetone. The sulfonation time was measured, and the post-treatment techniques, surface characterizations, were conducted using scanning electron microscopy (SEM) (Electron Optics Instruments, LLC., West Orange, NJ, USA), atomic force microscopy (AFM) (AFM, Vía Burton, CA, USA), and hydrophilic properties. The results were confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The findings of this study demonstrate that sulfonating PEEK caused a structure with a porous network to form in every sample. As the sulfonation time increased, the porous structure became more noticeable and the concentration increased. As a consequence, the roughness of the surface increased notably, and the modified PEEK surface's wettability improved noticeably. Hydrothermal treatment was determined to be the most successful way for eliminating the leftover sulfuric acid, and sulfonation for 2 min was determined to be ideal. By understanding the best post-treatment procedures and ideal sulfonation duration, a theoretical foundation for the production of sulfonated PEEK for orthopedic uses may be laid. [ABSTRACT FROM AUTHOR]

In this study, an analysis of the behavior of the vertebra during the use of KP and SJ was carried out to understand the kinematics of the movement of the fragments of the vertebra during action and the forces generated in the use of the two methods. For this analysis, the results published by various authors were used. Only the principle of the mechanical actuation of the vertebra fragments was analyzed, without addressing other aspects such as the method of cement introduction, the type of cement used, PMMA hardening times, the duration of the operation, the patient's recovery time, etc. In addition to the analysis, the authors propose a device that eliminates the inconveniences observed in the two analyzed devices and promises to significantly improve the restoration of the vertebra's height and, consequently, the patient's symptoms. The observations show that the type of mechanism articulated at one end has both robustness and greater efficiency in this type of actuation. It is further shown that from this category, the mechanism with two arms (Two-Arm Device) proposed by the authors is superior to the existing ones in terms of robustness and efficiency. The perspectives of TAD are represented by the improvement of the vertebral statics and, consequently, the symptoms of the patients. [ABSTRACT FROM AUTHOR]

Background: Anterior cervical discectomy and fusion (ACDF) is a standard procedure for degenerative diseases of the cervical spine, providing nerve decompression and spinal stabilization. However, it limits cervical spine motility, restricts fused segment activity, and may lead to adjacent degeneration. Cervical disc arthroplasty (CDA) is an accepted alternative that preserves the structure and flexibility of the cervical spine. This study aimed to explore the dynamic changes in the range of motion (ROM) of the cervical spine after CDA using a viscoelastic artificial disc, as well as the factors affecting mobility restoration. Methods: A retrospective analysis was conducted on 132 patients who underwent single-level anterior cervical discectomy and CDA from January 2015 to June 2022. Result: Analysis of data from 132 patients revealed a significant improvement in clinical outcomes. The mean ROM of C2–C7 and functional spinal unit (FSU) segments significantly increased from 2 to 36 months post-operatively. Cervical spine flexibility was preserved and enhanced after prosthesis implantation. However, it took six months for the cervical spine motility to stabilize. In addition, sex and age were found to impact motility restoration, with female and younger patients exhibiting larger ROMs post-surgery. Additionally, CDA at the C5–C6 level resulted in the greatest increase in ROM, potentially improving overall kinematic ability. Conclusions: Single-segment artificial disc arthroplasty effectively restores the ROM in degenerative cervical spine conditions. [ABSTRACT FROM AUTHOR]

The occurrence of bone diseases has been increasing rapidly, in line with the aging population. A representative spinal fusion material, polyetheretherketone (PEEK), is advantageous in this regard as it can work in close proximity to the elastic modulus of cancellous bone. However, if it is used without surface modification, the initial osseointegration will be low due to lack of bioactivity, resulting in limitations in surgical treatment. In this study, we aimed to modify the surface of PEEK cages to a hydrophilic surface by coating with polyethylene glycol (PEG), hyaluronic acid (HA), and polydopamine (PDA), and to analyze whether the coated surface exhibits improved bioactivity and changes in mechanical properties for orthopedic applications. Material properties of coated samples were characterized and compared with various PEEK groups, including PEEK, PEEK-PEG, PEEK-HA, and PEEK-PDA. In an in vitro study, cell proliferation was found to be enhanced on PDA-coated PEEK; it was approximately twice as high compared to the control group. In addition, mechanical properties, including static and torsion, were not affected by the presence of the coating. Thus, the results suggest that PEEK-PDA may have the potential for clinical application in fusion surgery for spinal diseases, as it may improve the rate of osseointegration. [ABSTRACT FROM AUTHOR]

This study examined the efficacy of computed tomography (CT)-based Hounsfield units (HU) as early predictors of aseptic bone necrosis, a serious post-cranioplasty complication after autologous cranioplasty. In total, 100 patients who underwent decompressive craniectomy and subsequent autologous cranioplasty were included. The radiodensity of the bone flap was evaluated in HU from CT scans at five follow-up timepoints. HU thresholds were established to predict the development of aseptic bone necrosis. HU demonstrated a declining trend throughout the follow-up period in all patients. Necrosis type I patients showed significant differences at all timepoints from 3 months post-procedure onwards, while necrosis type II patients displayed a significant decline in HU at every follow-up. Optimal thresholds with cut-off A (91.23% of initial HU) and cut-off B (78.73% of initial HU) were established to predict the occurrence of bone necrosis and the need for artificial bone replacement, respectively. Our findings demonstrated the utility of CT-based HU measurements as a simple, non-invasive tool for the early prediction of aseptic bone necrosis following autologous cranioplasty. By delineating specific HU thresholds, our study offers a valuable guide for orchestrating timely follow-ups and advising patients on the necessity of proactive interventions. [ABSTRACT FROM AUTHOR]

Background: The Internet is an important source of information for patients, but its effectiveness relies on the readability of its content. Patient education materials (PEMs) should be written at or below a sixth-grade reading level as outlined by agencies such as the American Medical Association. This study assessed PEMs' readability for the novel anterior vertebral body tethering (AVBT), distraction-based methods, and posterior spinal fusion (PSF) in treating pediatric spinal deformity. Methods: An online search identified PEMs using the terms "anterior vertebral body tethering," "growing rods scoliosis," and "posterior spinal fusion pediatric scoliosis." We selected the first 20 general medical websites (GMWs) and 10 academic health institution websites (AHIWs) discussing each treatment (90 websites total). Readability tests for each webpage were conducted using Readability Studio software. Reading grade levels (RGLs), which correspond to the US grade at which one is expected to comprehend the text, were calculated for sources and independent t tests compared with RGLs between treatment types. Results: The mean RGL was 12.1 ± 2.0. No articles were below a sixth-grade reading level, with only 2.2% at the sixth-grade reading level. AVBT articles had a higher RGL than distraction-based methods (12.7 ± 1.6 vs 11.9 ± 1.9, P = 0.082) and PSF (12.7 ± 1.6 vs 11.6 ± 2.3, P = 0.032). Materials for distraction-based methods and PSF were comparable (11.9 ± 1.9 vs 11.6 ± 2.3, P = 0.566). Among GMWs, AVBT materials had a higher RGL than distraction-based methods (12.9 ± 1.4 vs 12.1 ± 1.8, P = 0.133) and PSF (12.9 ± 1.4 vs 11.4 ± 2.4, P = 0.016). Clinical Relevance: Patients' health literacy is important for shared decision-making. Assessing the readability of scoliosis treatment PEMs guides physicians when sharing resources and discussing treatment with patients. Conclusion: Both GMWs and AHIWs exceed recommended RGLs, which may limit patient and parent understanding. Within GMWs, AVBT materials are written at a higher RGL than other treatments, which may hinder informed decision-making and patient outcomes. Efforts should be made to create online resources at the appropriate RGL. At the very least, patients and parents may be directed toward AHIWs; RGLs are more consistent. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have shown the correlation between lumbosacral sagittal plane parameters and natural absorption of lumbar disc herniation. However, the lumbosacral sagittal plane parameters included lumbar lordosis angle, lumbosacral joint angle, sacral inclination angle and many other parameters. The effects of each parameter on the natural absorption of the herniated disc were different. In addition, there are few studies on the reabsorption of a specific segment of intervertebral disc herniation at present, and most of the measured data are obtained from digital radiography or CT, while the correlation between lumbosacral sagittal plane parameters measured from MRI and reabsorption after L5/S1 intervertebral disc herniation is rarely reported. OBJECTIVE: To study the corresponding changes of lumbar sagittal plane parameters after L5/S1 intervertebral disc herniation reabsorption and to screen out the lumbosacral sagittal plane parameters with the most significant changes during intervertebral disc reabsorption. METHODS: Totally 57 patients with lumbar disc herniation who had complete MRI image data were selected and met the diagnostic criteria for lumbar disc herniation and only received non-surgical treatment for reabsorption of L5/S1 protrusion segments. MRI measured the protrusion area of the maximum protrusion plane in the coronal plane, lumbosacral sagittal plane parameters [lumbar curvature index, lumbar lordosis (α), L5/S1 disc angle (β), intervertebral height measurement, lumbosacral joint angle, sacral platform angle, sacral inclination angle, and lower lumbar lordosis angle]. Besides, lumbosacral sagittal plane parameters were ranked in the importance of variables by random forest model in R software, and then significant variables were fitted with multiple linear regression. The changes between parameters before and after treatment were analyzed and compared by paired sample t-test. RESULTS AND CONCLUSION: (1) A total of 57 patients with L5/S1 lumbar disc herniation were included in this study, and the symptoms and imaging features of the patients were significantly relieved to a large extent. (2) Before treatment, there were 4 cases of grade 1, 29 cases of grade 2 and 24 cases of grade 3 according to the Classification of Michigan State University. After treatment, there were 48 cases of grade 1 and 9 cases of grade 2. (3) The random forest model suggested that intervertebral height, lumbar curve index, sacral inclination angle, and lower lumbar lordosis angle changed significantly in L5/S1 disc herniation reabsorption, and the order of their change significance was lumbar curve index > intervertebral space height > sacral inclination angle > lower lumbar lordosis angle. (4) Lumbar curve index, lumbar lordosis and sacral platform angle increased, with statistical significance (P < 0.05). There were no significant differences in disc angle, intervertebral height, lower lumbar lordosis angle, sacral inclination angle or lumbosacral joint angle (P > 0.05). (5) Lumbar curvature index was the most significant parameter of the lumbosacral sagittal plane in herniated disc reabsorption. In addition, lumbar curve index, sacral inclination angle, and lower lumbar lordosis angle are commonly used clinically to describe the change of lumbar curvature, suggesting that L5/S1 disc herniation reabsorption is correlated with the change of lumbar curvature. It is indicated that in the treatment of lumbar disc herniation, a clinical cure can be achieved by improving or restoring the disordered lumbar curvature. [ABSTRACT FROM AUTHOR]

Objective: To examine the short-term efficacy and imaging results of using the Mobi-C in cervical hybrid surgery on 2-level cervical spondylolisthesis. To observe post-operative changes in the flexion–extension centre of rotation (FE-COR) and anterior bone loss (ABL) of the anterior cervical disc replacement (ACDR) segment. Methods: Forty-two patients (20 males and 22 females, aged 42‒67 years) who underwent cervical hybrid surgery were retrospectively analysed. Their ACDR segment used Mobi-C, and the fusion segment used ROI-C, with a follow-up of 25‒42 months (31.1 ± 4.8 months). The modified Japanese Orthopaedic Association (mJOA) score, Neck Disability Index (NDI), and visual analogue scale (VAS) were used to assess clinical outcomes. Pre-operative, 6-month post-operative, and final follow-up radiographs were collected to compare total cervical spine curvature (C2–C7), curvature of the operated segments, range of motion (ROM) in the total cervical spine, operated segmental ROM, ACDR segmental ROM, and operated adjacent segmental ROM. The height of the superior articular process (HSAP), the orientation of zygapophyseal joint spaces (OZJS), and the length of the superior articular surface (LSAS) were measured. The FE-COR of the ACDR segment was measured using the mid-plumb line method. The translation distance of the Mobi-C was measured. The degree of disc degeneration in the adjacent segment, bony fusion of the ACDF segment, and ABL of the upper and lower vertebra of the ACDR segment were observed. Results: In our group, all patients have shown improvements in their postoperative mJOA, NDI, and VAS scores. Overall cervical ROM and surgical segmental ROM decreased (P < 0.05). However, there was no significant decrease in ACDR segmental ROM and upper or lower adjacent segmental ROM compared with pre-operatively (P > 0.05). For FE-COR-X, only the last follow-up compared with pre-surgery showed statistical significance (46.74 ± 7.71% vs. 50.74 ± 6.92%, P < 0.05). For FE-COR-Y, the change was statistically significant at both 6 months post-operation and the final follow-up compared to pre-operation (45.37% ± 21.11% vs. 33.82% ± 10.87%, 45. 37% ± 21.11% vs. 27.48% ± 13.58%, P < 0.05). No significant difference in the Mobi-C translation distance was observed (P > 0.05). Moreover, the difference in HSAP was not statistically significant at each node (P > 0.05). The OZJS and LSAS were significantly different at the final follow-up compared to the pre-operative period (P < 0.05). All the ACDF segments were observed in a stable condition at the final follow-up. Furthermore, 9 of the adjacent segments showed imaging ASD (9/82, 10.98%), and all were present at the last follow-up, of which 6 were mild, and 3 were moderate. Twenty of the 42 Mobi-C segments had no significant ABL (grade 0) 6 months post-operatively (47.62%). Sixteen cases (38.10%) showed mild ABL (grade 1), and 6 cases (14.28%) showed moderate ABL (grade 2). No severe ABL occurred. Conclusion: The cervical hybrid surgery using Mobi-C artificial cervical discs can achieve satisfactory results. The Mobi-C segmental FE-COR-X shows a slow forward shift trend, and FE-COR-Y drops noticeably within 6 months post-surgery before stabilizing. It's common to see mild to moderate ABL after cervical hybrid surgery using Mobi-C, and significant progression is unlikely in the short term. Furthermore, changes in the FE-COR after hybrid surgery in the Mobi-C segment might not affect clinical outcomes. [ABSTRACT FROM AUTHOR]

In order to improve the quality of transplanting devices and solve the problems of the poor effect on soil moisture conservation and more weeds easily growing due to the high mulching-film damage rate with an excessive number of hole openings, we developed a dibble-type transplanting device consisting of a dibble-type transplanting unit, a transplanting disc, and a dibble axis. The ADAMS software Adams2020 (64bit) was used to simulate and analyze the kinematic track of the transplanting device. The results of the analysis show that, when the hole opening of the envelope in the longitudinal dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting angle was 95°, and the transplanting frequency had no influence. With the help of the ANSYS WORKBENCH software Ansys19.2 (64bit), an analysis of the process of the formation of an opening in the mulching film and a mechanical simulation of this process were completed. The results indicate that, when the maximum shear stress of the mulching film was the smallest, the transplanting characteristic coefficient was 1.000, the transplanting frequency was 36 plants·min−1, and the transplanting angle was 95°. In addition, the device was tested in a film-breaking experiment on a soil-tank test bench to verify the hole opening in the mulching film. The bench test showed that, when the longitudinal dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting frequency was 36 plants·min−1, and the transplanting angle was 95°. When the lateral dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting frequency was 36 plants·min−1, and the transplanting angle was 90°. The theoretical analysis, kinematic simulation, and soil-tank test results were consistent, verifying the validity and ensuring the feasibility of the transplanting device. This study provides a reference for the development of transplanting devices. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE: To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS: The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively. The established model was imported into 3-Matic software in the format of "Stl" to reconstruct the intervertebral disc,and the fibrous interve rtebral disc model was obtained. The improved model was further imported into Hypermesh software,and the ve rtebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each ve rtebral body in seven different working conditions of T11-S1, and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION: (1) The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation (left and right),and lateral flexion (left and right). The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension. (2) The annular fiber flexion at L2-L3 segments was greater than the extension (P ＜0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension (P ＜0.05). The left rotation of L1-L2 annular fibers was greater than the right rotation (P ＜0.05). The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments (P ＜0.05). (3) The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension (P ＜0.05). The left rotation of T12-L1and L3-L4 segments was smaller than the right rotation (P ＜0.05),and that of T11-T12、L1-L2,and L2-L3 segments was larger than the right rotation (P ＜0.05). The left flexion was larger than the right flexion in the T11-S1 segment. (4) It is concluded that in ankylosing spondylitis patients with lumbar kyphosis, the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures, it is recommended to avoid exercise in the extension position. During the onset of lumbar kyphosis in patients with ankylosing spondylitis, the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment, which is fixed and will not alter with the change of body position. The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus. [ABSTRACT FROM AUTHOR]

Background: Access to blood products is crucial for patient safety during the perioperative course. However, reduced donations and seasonally occurring blood shortages pose a significant challenge to the healthcare system, with surgeries being postponed. The German Blood Transfusion act requires that RBC packages become assigned to an individual patient, resulting in a significant reduction in the available blood products, further aggravating shortages. We aimed to develop a scoring system predicting transfusion probability in patients undergoing spine surgery to reduce assignment and, thus, increase the availability of blood products. Methods: The medical records of 252 patients who underwent spine surgery were evaluated and 18 potential predictors for RBC transfusion were tested to construct a logistic-regression-based predictive scoring system for blood transfusion in patients undergoing spine surgery. Results: The variables found to be the most important included the type of surgery, vertebral body replacement, number of stages, and pre-operative Hb concentration, indicating that surgical specification and the extent of the surgical procedure were more influential than the pre-existing patient condition and medication. Conclusions: Our model showed a good discrimination ability with an average AUC [min, max] of 0.87 [0.6, 0.97] and internal validation with a similar AUC of 0.84 [0.66, 0.97]. In summary, we developed a scoring system to forecast patients' perioperative transfusion needs when undergoing spine surgery using pre-operative predictors, potentially reducing the need for RBC allocation and, thus, resulting in an increased availability of this valuable resource. [ABSTRACT FROM AUTHOR]

This article discusses the potential benefits of using the endoscopic endonasal approach (EEA) for atlantoaxial fixation, a surgical treatment for cervical spine instability. The traditional posterior approach is associated with various risks and complications. Through cadaveric studies, the authors demonstrate that the EEA is a feasible alternative with comparable biomechanical stability. They advocate for the development of specialized tools for cervical fixation through the EEA, which could potentially decrease postoperative complications, morbidity, and mortality, especially in patients with certain anatomical limitations. [Extracted from the article]

In patients undergoing cervical spine surgery for metastatic spine disease, we sought to 1) compare perioperative and oncologic outcomes among 3 different operative approaches, 2) report fusion rates, and 3) compare different types of anterior vertebral body replacement. A single-center retrospective cohort study of patients undergoing extradural cervical/cervicothoracic spine metastasis surgery between February 2010 and January 2021 was conducted. Operative approaches were anterior-alone, posterior-alone, or combined anterior-posterior, and the grafts/cages used in the anterior fusions were cortical allografts, static cages, or expandable cages. All cages were filled with autograft/allograft. Outcomes included perioperative/postoperative variables, along with fusion rates, functional status, local recurrence (LR), and overall survival (OS). Sixty-one patients underwent cervical spine surgery for metastatic disease, including 11 anterior (18.0%), 28 posterior (45.9%), and 22 combined (36.1%). New postoperative neurologic deficit was the highest in the anterior approach group (P = 0.038), and dysphagia was significantly higher in the combined approach group (P = 0.001). LR (P > 0.999), OS (P = 0.655), and time to both outcomes (log-rank test, OS, P = 0.051, LR, P = 0.187) were not significantly different. Of the 51 patients alive at 3 months, only 19 (37.2%) obtained imaging ≥3 months. Fusion was seen in 11/19 (57.8%) at a median of 8.3 months (interquartile range, 4.6–13.7). Among the anterior corpectomies, the following graft/cage was used: 6 allografts (54.5%), 4 static cages (36.3%), and 1 expandable cage (9.0%), with no difference found in outcomes among the 3 groups. The only discernible differences between operative approaches were that patients undergoing an anterior approach had higher rates of new postoperative neurologic deficit, and the combined approach group had higher rates of postoperative dysphagia. [ABSTRACT FROM AUTHOR]

Spinal endoscopy has evolved significantly since its inception, offering minimally invasive solutions for various spinal pathologies. This study introduces a promising innovation in spinal endoscopy—a single-use digital endoscope designed to overcome the drawbacks of traditional optic endoscopes. Traditional endoscopes, despite their utility, present challenges such as fragility, complex disinfection processes, weight issues, and susceptibility to mechanical malfunctions. The digital endoscope, with its disposable nature, lighter weight, and improved image quality, aims to enhance surgical procedures and patient safety. The digital endoscope system comprises a 30-degree 1000 × 1000 pixel resolution camera sensor with a 4.3 mm working channel, and LED light sources replacing optical fibers. The all-in-one touch screen tablet serves as the host computer, providing portability and simplified operation. Image comparisons between the digital and optic endoscopes revealed advantages in the form of increased field of view, lesser distortion, greater close-range resolution, and enhanced luminance. The single-use digital endoscope demonstrates great potential for revolutionizing spine endoscopic surgeries, offering convenience, safety, and superior imaging capabilities compared to traditional optic endoscopes. [ABSTRACT FROM AUTHOR]

Background: Vertebral osteomyelitis (VO) often necessitates surgical intervention due to bone loss-induced spinal instability. Anterior column reconstruction, utilizing expandable vertebral body replacement (VBR) implants, is a recognized approach to restore stability and prevent neurological compromise. Despite various techniques, clinical evidence regarding the safety and efficacy of these implants in VO remains limited. Methods: A retrospective cohort analysis, spanning 2000 to 2020, was conducted on 24 destructive VO cases at a Level 1 orthopedic trauma center. Diagnosis relied on clinical, radiological, and microbiological criteria. Patient demographics, clinical presentation, surgical interventions, and radiological outcomes were assessed. Results: The study included 24 patients (62.5% male; mean age 65.6 ± 35.0 years), with 58% having healthcare-associated infections (HAVO). The mean radiological follow-up was 137.2 ± 161.7 weeks. Surgical intervention significantly improved the bi-segmental kyphotic endplate angle (BKA) postoperatively (mean −1.4° ± 13.6°). However, a noticeable loss of correction was observed over time. The study reported a mortality rate of 1/24. Conclusions: Anterior column reconstruction using expandable VBR effectively improved local spinal alignment in destructive VO. However, the study underscores the necessity for prolonged follow-up and continuous research to refine surgical techniques and postoperative care. Addressing long-term complications and refining surgical approaches will be pivotal as the field progresses. [ABSTRACT FROM AUTHOR]

Purpose: To characterize the change of adjacent segment degeneration (ASD) after cervical total disc replacement (CTDR) with more than 12-year follow-up, and identify the risk factors for ASD. Method: This process included 75 patients underwent CTDR from February 2004 to December 2012, with the follow-up of 151.9 ± 36.0 (m). The artificial disc included ProDisc-C, Prestige-LP and Mobi-C. ASD was followed up at 1 week, 6 months, 1 year, 2 years, 5 years, 10 years after CTDR and at the endpoint of June 2022. The radiographic measurements were cervical mobility, intervertebral disc height (IDH), cervical lordosis and balance status. The complications were implant migration, subsidence and heterotopic ossification (HO). Results: Cervical mobility in adjacent segments, IDH and lordosis showed no statistical differences between ASD and NASD group. Balance status, subsidence and migration showed no relationship with ASD. Postoperative ASD increased at 6 m and especially between 6 m to 2y. There was no difference between the incidence of upper ASD and lower ASD all the time and few ASD-related reoperation. The majority of adjacent segments were C4/5 (33.6%) and C6/7 (34.2%), and ASD of C5/6 had the highest incidence (61.5%). Cox regression showed ASD was not related to the types of prosthesis or operated numbers. Generalized estimating equations (GEE) analysis showed severe HO had a higher (2.68 times) probability to suffer from ASD. Conclusions: After over 12-year follow-up of CTDR, the occurrence of ASD and HO had temporal synchronization. ASD was not merely a natural progression but with the pathological process such as HO. [ABSTRACT FROM AUTHOR]

Though cage-and-plate constructs are widely used for disk height restoration in surgery for cervical disc disease, concerns over range of motion limitations and adjacent disc space violations have fueled the development of artificial disc and zero-profile constructs. This study investigated the outcomes of patients undergoing two-level cervical interventions via arthroplasty, cage-and-plate, or zero-profile constructs. Patients undergoing two-level anterior cervical procedures between 2010 and 2020 were identified using an all-payer claims database. Logistic regression models were utilized to develop criteria for a 1:1:1-exact match procedure. The primary outcome was the need for additional surgery within 30 months, and the secondary outcomes included medical and surgical complications observed within 30 days of index intervention. P values < 0.05 were considered statistically significant. 133,831 patients were identified as undergoing two-level anterior cervical interventions. Seven thousand three hundred seventy-one records were analyzed through a 1:1:1 match. Patients who received zero-profile versus cage-and-plate constructs had significantly decreased odds of requiring additional surgery within 30 months (Odds Ratio [OR] 0.64; 95% Confidence Interval [CI] 0.51–0.81). However, postoperative medical complications were increased among patients who received zero-profile constructs compared to cage-and-plate (OR 1.59; 95%CI 1.07–2.37). Patients who underwent arthroplasty also had decreased odds for additional surgery versus cage-and-plate (OR 0.75; 95%CI 0.60–0.93). There was no significant difference between arthroplasty and cage-and-plate constructs in developing postoperative surgical or medical complications. Among patients undergoing two-level interventions, cage-and-plate constructs were associated with increased odds of additional surgery within 30 months following index procedures when compared to zero-profile constructs or arthroplasty. [ABSTRACT FROM AUTHOR]

In the evolving landscape of spinal surgery, technological advancements play a pivotal role in enhancing surgical outcomes and patient experiences. This paper delves into the cutting-edge technologies underpinning endoscopic spine surgery (ESS), specifically highlighting the innovations in scope cameras, RF equipment, and drills. The modern scope camera, with its capability for high-resolution imaging, offers surgeons unparalleled visualization, enabling precise interventions. Radiofrequency (RF) equipment has emerged as a crucial tool, providing efficient energy delivery for tissue modulation without significant collateral damage. Drills, with their enhanced torque and adaptability, allow for meticulous bone work, ensuring structural integrity. As minimally invasive spine surgery (MISS) becomes the standard, the integration and optimization of these technologies are paramount. This review captures the current state of these tools and anticipates their continued evolution, setting the stage for the next frontier in spinal surgery. [ABSTRACT FROM AUTHOR]

Background: Surgical treatment of vertebral osteomyelitis, discitis, and epidural abscesses is indicated in the setting of failure of antibiotic therapy, neurological deficits, epidural abscess, or spinal instability/deformity. Historically, surgical treatment mandated aggressive debridement and spinal stabilization. However, there is growing evidence that direct debridement may not be necessary and may contribute to morbidity. The purpose of this study was to evaluate the efficacy of posterior instrumentation without debridement in treating spinal infections. Methods: A retrospective medical record review was performed to identify patients treated with posterior instrumentation for spontaneous spinal infections. Success of treatment was determined based on postoperative ambulatory status, surgical complications, and need for revision surgery. Results: Twenty-seven patients treated with posterior-only long-segmented rigid fixation without formal debridement of infected material were included. The most common indications for surgical intervention included spinal instability (67%), neurologic compromise (67%), and failure of prolonged antibiotic treatment (63%). There were no recurrent deep infections in 21 of 22 patients who had long-term follow-up. Four patients required revision surgery, and 3 additional patients requested elective hardware removal. Postoperatively, 70% were ambulatory with no assistive devices postoperatively. Conclusions: Vertebral osteomyelitis/discitis are challenging medical problems. Single-stage long-segment fusion without formal debridement combined with antibiotics is effective in the management of spontaneous spinal infections. Clinical Relevance: The present study suggests that acute instrumentation without anterior debridement is associated with a resolution of infection and improvements in neurologic deficits in patient with spontaneous spine infections. [ABSTRACT FROM AUTHOR]

Background: Tissue‐engineered intervertebral disc (TE‐IVD) constructs are an attractive therapy for treating degenerative disc disease and have previously been investigated in vivo in both large and small animal models. The mechanical environment of the spine is notably challenging, in part due to its complex anatomy, and implants may require additional mechanical support to avoid failure in the early stages of implantation. As such, the design of suitable support implants requires rigorous validation. Methods: We created a FE model to simulate the behavior of the IVD cages under compression specific to the anatomy of the porcine cervical spine, validated the FE model using an animal model, and predicted the effects of implant location and vertebral angle of the motion segment on implant behavior. Specifically, we tested anatomical positioning of the superior vertebra and placement of the implant. We analyzed corresponding stress and strain distributions. Results: Results demonstrated that the anatomical geometry of the porcine cervical spine led to concentrated stress and strain on the posterior side of the cage. This stress concentration was associated with the location of failure of the cages reported in vivo, despite superior mechanical properties of the implant. Furthermore, placement of the cage was found to have profound effects on migration, while the angle of the superior vertebra affected stress concentration of the cage. Conclusions: This model can be utilized both to inform surgical procedures and provide insight on future cage designs and can be adopted to models without the use of in vivo animal models. [ABSTRACT FROM AUTHOR]

Objective : Anterior cervical spine surgery (ACSS) is a common surgical procedure used to treat cervical spinal degenerative diseases. One of the complications associated with ACSS is prevertebral soft tissue swelling (PSTS), which can result in airway obstruction, dysphagia, and other adverse outcomes. This study aims to investigate the correlation between various cervical sagittal parameters and PSTS following single-level ACSS, as well as to identify independent risk factors for PSTS. Methods : A retrospective study conducted at a single institution. The study population included all patients who underwent single-level ACSS between January 2014 and December 2022. Patients with a history of cervical spine surgery or trauma were excluded from the study. The presence and severity of PSTS was assessed by reviewing pre- and postoperative imaging studies. The potential risk factors for PSTS that were examined include patient age, sex, body mass index, tobacco use, comorbidities, serum albumin levels, operative time, implant type, implanted level, and various cervical spine sagittal parameters. Multivariate linear regression analysis was performed to identify the independent risk factors for PSTS. Results : A total of 62 consecutive patients who underwent single-level ACSS over a 8-year period at a single institution were enrolled in this study. Only preoperative segmental angle showed positive correlation with PSTS among various cervical spine sagittal parameters (r=0.36, p=0.005). Artificial disc replacement showed a negative correlation with PSTS (β=-0.38, p=0.002), whereas the use of demineralized bone matrix (DBM) had a positive impact on PSTS (β=0.33, p=0.009). We found that male sex, lower preoperative serum albumin, and implantation of upper cervical level (above C5) were independent predictors for PSTS after single-level ACSS (β=1.21; 95% confidence interval [CI], 0.27 to 2.15; p=0.012; β=-1.63; 95% CI, -2.91 to -0.34; p=0.014; β=1.44; 95% CI, 0.38 to 2.49; p=0.008, respectively). Conclusion : Our study identified male sex, lower preoperative serum albumin levels, and upper cervical level involvement as independent risk factors for PSTS after single-level ACSS. These findings can help clinicians monitor high-risk patients and take preventive measures to reduce complications. Further research with larger sample sizes and prospective designs is needed to validate these findings. [ABSTRACT FROM AUTHOR]

The purpose of this case report is to describe the case of a patient with ankylosing spinal hyperostosis (ASH) and lumbar spine fracture complicated by ureteral injury mimicking spondylodiscitis with osteomyelitis features and retroperitoneal abscess formation followed by the cervical spine fracture. A consecutive analysis and summary of the medical history, radiological documentation, operative procedure, complications, and outcomes were performed. A 59-year-old man presented with abdominal pain three weeks after sustaining a low-energy fall. The performed CT scans demonstrated a three-column fracture at the L3/L4 level and features of ASH. Additionally, MRI scans demonstrated hyperintense fluid collection within L3/L4 intervertebral space communicating with both psoas major muscles, mimicking spondylodiscitis with osteomyelitis features and retroperitoneal abscess formation. An in situ instrumented lumbar fusion at the L2-L3-L5-S1 levels with implantation vertebral body replacement implant at the L3/L4 level was performed. Postoperative CT imaging revealed evidence of post-traumatic right ureteral injury. Following urological treatment covering nephrectomy and ureter ligation, the patient was maintained at a 2-year follow-up. After this period, the patient presented again with tetraparesis after sustaining a low-energy fall. The performed CT scans demonstrated a three-column fracture at the C5/C6 level. The combined anterior and posterior osteosynthesis at the C4-C5-C6-C7 levels was performed. This case report presents the rare clinical constellation regarding the lumbar spine fracture complicated by ureteral injury followed by a cervical spine fracture regarding the same patient. The potential injury of retroperitoneal structures, including the ureter after hyperextensive lumbar spine fracture, should be considered in ASH patients. In this case, one should be aware of the atypical clinical presentation regarding the observed spondylodiscitis- and osteomyelitis-like features. [ABSTRACT FROM AUTHOR]

Objective • This study aims to assess the comparative effectiveness of posterior lumbar interbody fusion (PLIF) and percutaneous transforaminal endoscopic discectomy (PTED) in the treatment of various grades of intervertebral disc herniation (IDH) and evaluate the added value of incorporating McKenzie therapy-based lumbar spine rehabilitation care. Methods • A retrospective analysis was conducted on 83 patients diagnosed with IDH admitted to our hospital between May 2020 and June 2022. Among these patients, 43 underwent PLIF (PLIF group), while the remaining 40 received PTED treatment (PTED group). Parameters such as operative time, intraoperative bleeding, hospitalization duration, Visual Analogue Score (VAS), and Oswestry Disability Index (ODI) were measured in both groups before and after the procedures. Additionally, 74 IDH patients were randomly assigned to either a research group receiving McKenzie therapy (n = 37) or a control group receiving standard care (n = 37). VAS and ODI scores were recorded pre- and post-intervention in both groups, and lumbar forward flexion joint range of motion (ROM) was assessed. Results • The PTED group demonstrated shorter operative times, reduced intraoperative bleeding, and shorter hospital stays compared to the PLIF group (P < .05). One month after surgery, no significant differences in VAS and ODI were observed between the PLIF and PTED group patients with Pfirrmann class II-III herniation (P > .05). However, Pfirrmann class IV patients in the PLIF group exhibited lower VAS and ODI scores compared to those in the PTED group (P < .05). Following rehabilitation care, the research group exhibited lower VAS and ODI scores and greater ROM compared to the control group (P < .05). Conclusions • PTED is characterized by reduced surgical trauma, shorter operative duration, and decreased intraoperative bleeding, while PLIF offers complete removal of the affected disc and stable intervertebral fusion. Integrating McKenzie therapy-based rehabilitation care further enhances lumbar spine function and alleviates pain in patients. [ABSTRACT FROM AUTHOR]

Total en bloc spondylectomy (TES) effectively treats spinal tumors. The surgery requires a vertebral body replacement (VBR), for which several solutions were developed, whereas the biomechanical differences between these devices still need to be completely understood. This study aimed to compare a femur graft, a polyetheretherketone implant (PEEK-IMP-C), a titan mesh cage (MESH-C), and a polymethylmethacrylate replacement (PMMA-C) using a finite element model of the lumbar spine after a TES of L3. Several biomechanical parameters (rotational stiffness, segmental range of motion (ROM), and von Mises stress) were assessed to compare the VBRs. All models provided adequate initial stability by increasing the rotational stiffness and decreasing the ROM between L2 and L4. The PMMA-C had the highest stiffness for flexion–extension, lateral bending, and axial rotation (215%, 216%, and 170% of intact model), and it had the lowest segmental ROM in the instrumented segment (0.2°, 0.5°, and 0.7°, respectively). Maximum endplate stress was similar for PMMA-C and PEEK-IMP-C but lower for both compared to MESH-C across all loading directions. These results suggest that PMMA-C had similar or better primary spinal stability than other VBRs, which may be related to the larger contact surface and the potential to adapt to the patient's anatomy. [ABSTRACT FROM AUTHOR]

Vertebral body replacement (VBR) cages are commonly implanted to reconstruct the cervical vertebrae in cases of tumour, trauma, spondylodiscitis, and degeneration. Expandable cages have been widely used for this purpose; however, the lacking congruence at the implant-bone interface and consequent implant displacement were considered as a serious drawback of such systems. Aim of this study is to evaluate the early clinical and radiological outcome of a modern in situ not only expandable but also angulable cervical corpectomy cage system. A total of 42 patients who underwent a single or multilevel cervical VBR procedure were included and retrospectively evaluated in this single-centre case series. The neurological status was assessed using American Spinal Injury Association (ASIA) score. Complications were categorized into surgical (including implant-associated) and general medical. Radiographic parameters included regional angulation, segmental height, and coronal alignment. Mean age was 59.5 ± 20.6 years. The recorded ASIA score improved postoperatively by 10 points (p 0.0001). Surgical including implant-associated complication rates were 19.05%. Radiographic evaluation showed a height gain of 11.2 mm (p < 0.0001), lordotic correction of 7° (p < 0.0001), and coronal alignment of 3° (p < 0.0001). At the last follow-up, loss of angulation correction of 1.9° (p 0.0002), subsidence of 1.92 mm (p 0.0006), and fusion rates of 68.42% were observed. The use of an in situ angulable and expandable cage system in cervical VBR seems to offer better results compared to conventional static or expandable cages regarding segmental height gain, lordotic correction, and clinical improvement as well as low complication and revision rates. Significant height gain in multilevel surgeries is associated with higher rates of implant-associated complications. [ABSTRACT FROM AUTHOR]

The prevalence of lumbar disc herniation (LDH), which makes patients' daily activities more difficult and reduces their quality of life, has tended to increase recently. Many risk factors associated with LDH have been reported. In this study, LDH was predicted using machine learning techniques using measures of the lumbar paraspinal muscles, lumbar vessels cross-sectional area (CSA), and lumbar sagittal curve. Three hundred and forty-four individuals' MR scans were prospectively enrolled (264 with LDH and 80 healthy). Predictive factors were the lumbar sagittal curve and the cross-sectional areas of the lumbar paraspinal muscles and vessels from sagittal and axial MR images. The measurements have been analyzed via ten different and most common machine learning algorithms by considering a comprehensive parameter tuning and cross-validation process. The variable importance results have been also presented. XGBoost algorithm among all algorithms has provided the best results in terms of different classification metrics including f-score ( 0.830 ), AUC ( 0.939 ), accuracy ( 0.922 ), and kappa ( 0.779 ). The findings of this study demonstrated that cross-sectional areas of the quadratus lumborum and abdominal aorta can be utilized as a reliable indicator of LDH. Consequently, the developed model and the variables found to be important may guide to healthcare professionals to make more accurate and effective decisions in terms of prediction the LDH. [ABSTRACT FROM AUTHOR]

Lumbar disc herniation is a common disease that causes low back pain. Due to the high cost of medical diagnosis, as well as a shortage and uneven distribution of medical resources, a system that can automatically analyze and diagnose lumbar spine Magnetic Resonance Imaging (MRI) is becoming an urgent need. This study uses deep learning methods to establish a classifier to diagnose lumbar disc herniation. An MRI classification dataset of lumbar disc herniation consisting of public MRI images is presented and is used to train the proposed classifier. Because a common difficulty in applying computer vision technology to medical images is labeling training data, we use a semi-supervised model training method, while multilayer transverse axial MRI images are used as the model input. In this method, we first use unlabelled MRI images for random self-supervised pre-training and the pre-trained model as a feature extractor for MRI images. Then, all marked cross-sections of each intervertebral disc are used to calculate the feature vector through the feature extractor. The information of all feature vectors is integrated, while a multilayer perceptron is used for classification training. After training, the model achieved 87.11 % accuracy, 87.50 % sensitivity, 86.72 % specificity and 0.9487 AUC (Area Under the ROC Curve) index on the test set. To analyze the rationality of the diagnostic results more quickly, we output the severity of degenerative changes in each region using a heatmap. [ABSTRACT FROM AUTHOR]

BACKGROUND: Intervertebral implant subsidence is one of the common complications after anterior cervical decompression and fusion, and it is important to understand this complication. OBJECTIVE: To summarize the domestic and foreign articles on the subsidence of intervertebral implants after anterior cervical decompression and fusion in order to provide clinical guidance for spine surgeons. METHODS: A computed-based online retrieval of CNKI, Wanfang and PubMed databases was conducted with Chinese and English keywords of “intervertebral implant, subsidence, anterior cervical decompression and fusion, cage, review, biomechanical analysis, three-dimensional finite element, three-dimensional printing technology, complications, biomaterials”. RESULTS AND CONCLUSION: (1) Among the preoperative factors, osteoporosis, lower body mass index, higher T1 slope and inverted cervical spine angle were the risk factors for cage subsidence after anterior cervical approach. (2) C6/7 is the most common segment for the subsidence of the interbody cage after anterior cervical approach. The incidence of long segments is higher than that of short segments. Most articles believe that titanium plate-cage internal fixation system can effectively reduce the subsidence risk. (3) The width, diameter and height of the implant are related to the postoperative subsidence rate and the risk of subsidence increases when the implant is placed in the center of the endplate. (4) Rectangular, anatomical, 12-lobed, porous structure cage and bionic pit surface can effectively reduce the risk of subsidence when placed on the side of the cage. (5) Compared with titanium alloy cages, polyether ether ketone cages have lower subsidence risk. Degradable materials and composite materials have been studied more in recent years, but their safety and effectiveness still need to be further proved. (6) Excessive curettage of the endplate, excessive distraction of the intervertebral body, prolonged distraction of the cervical retractor, poor screw placement, and poor implant placement angle are the risk factors of postoperative intervertebral implant subsidence; premature cervical collar removal after surgery increases the risk of subsidence. (7) Biomechanical research, materials research, 3D printing technology, and long-term follow-up are effective ways to study the subsidence of intervertebral implants after anterior cervical decompression and fusion in the future. [ABSTRACT FROM AUTHOR]

We report the case of a 1‐year‐old, male, entire Patagonian mara (Dolichotis patagonum) presented unable to walk as a result of a traumatic comminuted vertebral fracture/luxation and successfully treated with surgical stabilisation using pins and polymethyl methacrylate. The diagnosis was based on neurological examination and computed tomography. The surgery was performed the same day of presentation and the patient recovered well after surgery, eating, urinating and defecating within the next 24 hours. In this paper, we discuss the anaesthetic and peri‐anaesthetic management as well as the postoperative medical considerations, focusing on important anatomical aspects of the species and the surgical procedure that has not been described in maras before. [ABSTRACT FROM AUTHOR]

The International Journal of Spine Surgery has dedicated its December 2023 issue to examining complications and outcomes in spine surgery, with a focus on cervical arthroplasty. Cervical artificial disc replacement (c-ADR) is a successful and extensively studied procedure in spinal surgery. The article emphasizes the importance of understanding and avoiding complications to improve outcomes. It discusses various complications associated with c-ADR, including dislocation, subsidence, osteolysis, recurrent radiculopathy, focal device kyphosis, and heterotopic ossification. The article also highlights the significance of patient selection and proper surgical techniques in minimizing complications. Revision strategies for different modes of failure are discussed, and the article concludes by emphasizing the importance of complication avoidance to prevent revision surgery and improve outcomes. [Extracted from the article]

Spinal disorders cover a broad spectrum of pathologies and are among the most prevalent medical conditions. The management of these health issues was noted to be increasingly based on surgical interventions. Spinal fixation devices are often employed to improve surgery outcomes, increasing spinal stability, restoring structural integrity, and ensuring functionality. However, most of the currently used fixation tools are fabricated from materials with very different mechanical properties to native bone that are prone to pull-out effects or fail over time, requiring revision procedures. Solutions to these problems presently exploited in practice include the optimal selection of screw shape and size, modification of insertion trajectory, and utilization of bone cement to reinforce fixation constructs. Nevertheless, none of these methods are without risks and limitations. An alternative option to increasing biomechanical resistance to the pull-out effect is to tackle bone regenerative capacity and focus on screw osteointegration properties. Osteointegration was reportedly enhanced through various optimization strategies, including use of novel materials, surface modification techniques (e.g., application of coatings and topological optimization), and utilization of composites that allow synergistic effects between constituents. In this context, this paper takes a comprehensive path, starting with a brief presentation of spinal fixation devices, moving further to observations on how the pull-out strength can be enhanced with existing methods, and further focusing on techniques for implant osteointegration improvement. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective single-center, single-surgeon cohort study. Purpose: Our goal was to compare the 2-year clinical and radiological results of artificial disc replacement (ADR) and cage screw (CS) implants in patients with cervical degenerative disc disease (DDD). Overview of Literature: Anterior cervical discectomy and fusion with CS implants are an acceptable alternative to traditional cageplate construct due to perceived decreased complications of dysphagia. However, patients may experience adjacent segment disease because of increased motion and intradiscal pressure. ADR is an alternative to restore the physiological kinematics of the operated disc. Few studies directly compare ADR and CS construct for their efficacy. Methods: Patients who received single-level ADR or CS between January 2008 and December 2018 were included. Data collected was preoperatively, intraoperatively, and postoperatively (6, 12, 24 months). Demographic information, surgical information, complications, follow-up surgery, and outcome ratings (Japanese Orthopaedic Association [JOA], Neck Disability Index [NDI], Visual Analog Scale [VAS] neck and arm, 36-item Short Form Health Survey [SF-36], EuroQoL-5 Dimension [EQ-5D]) were gathered. The radiological assessment included motion segment height, adjacent disc height, lordosis, cervical lordosis, T1 slope, the sagittal vertical axis C2-7, and adjacent level ossification development (ALOD). Results: Fifty-eight patients were included (ADR: 37 and CS: 21). At 6 months, both groups' JOA, VAS, NDI, SF-36, and EQ-5D scores significantly improved, and the positive trends persisted at 2 years. Noted no significant difference in the enhancement of clinical scores except for the VAS arm (ADR: 5.95 vs. CS: 3.43, p =0.001). Radiological parameters were comparable except for the progression of ALOD of the subjacent disc (ADR: 29.7% vs. CS: 66.9%, p =0.02). No significant difference in adverse events or severe complications seen. Conclusions: ADR and CS obtain good clinical results for symptomatic single-level cervical DDD. ADR demonstrated a significant advantage over CS in the improvement of VAS arm and reduced progression of ALOD of the adjacent lower disc. No statistically significant difference of dysphonia or dysphagia between the two groups were seen, attributed to their comparable zero profile. [ABSTRACT FROM AUTHOR]

Based on the finite element method， the effects of the size of artificial vertebral body (AVB) on the biomechanical properties of the reconstructed structure of vertebral body replacement and fusion (VBRF) was studied. Firstly， an Abaqus plug-in was developed， which could parametrically establish the three-dimensional model of AVB， and cooperate with the finite element model of the cervical spine to establish the finite element model of VBRF. Secondly， the finite element analysis was given to various VBRF models (different sizes of AVB). Finally， Pease value， an important index closely related to implant and vertebral fusion， was introduced and compared. The results showed that there is no significant difference in the Pease value under the condition of the same size of AVB and different wall thickness， but the size of AVB has a significant effect on the Pease value. The Pease value is relatively higher when the outer radius of AVB is in the range of 4~6mm， which is more conducive to the fusion of implants and vertebrae. [ABSTRACT FROM AUTHOR]

A 4-month-old female Scottish Fold kitten was presented for treatment of non-ambulatory paraplegia accompanied by urinary and fecal incontinence. Radiographs revealed T10 and T11 vertebral body fractures with spinal cord compression. Traditional Chinese veterinary medicine (TCVM) therapy which included acupuncture, Chinese herbal medicine, and Tui-na were used to address the paralysis and incontinence. Daily Tui-na was started along with laser acupuncture every other day when she was hospitalized. The Chinese herbal medicine formulas administered orally to the kitten included: Xiao Huo Luo Dan, Bu Yang Huan Wu and Shen Tong Zhu Yu. Three months after treatment, she could walk normally and the urinary and fecal incontinence had resolved. [ABSTRACT FROM AUTHOR]

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BACKGROUND: The core of anterior decompression is to relieve the compression of spinal cord and nerve and restore the intervertebral height and physiological curvature of cervical spine. However, the cage currently used in the clinic cannot satisfy the individualized needs, resulting in the destruction of the endplate of the fusion segment and the subsidence or displacement of the cage. In this study, a height adjustable cervical fusion cage was designed, which can be implanted into the intervertebral space to fit with the upper and lower end plates of the intervertebral space. OBJECTIVE: To evaluate the mechanical characteristics of the new height adjustable cervical fusion cage by three-dimensional finite element analysis, and to provide corresponding theoretical basis for clinical application and further improvement. METHODS: The three-dimensional finite element models of anterior cervical discectomy and fusion were established and the models were divided into normal group, lower cage implantation height group, moderate cage implantation height group and higher cage implantation height group. 50 N preload and 1.0 N·M motion additional bending moment were applied under six working conditions of flexion and extension, left and right lateral flexion and left and right rotation. The corresponding peak Von Mises stress of vertebral body, peak Von Mises stress of cage, intervertebral disc stress and C3-C7 vertebral motion range were observed. RESULTS AND CONCLUSION: (1) The peak Von Mises stress of fusion cage and the peak Von Mises stress of C3-C7 vertebral body in the group with moderate cage implantation height were lower than those in the group with lower cage implantation height and the group with higher cage implantation height. (2) The stress difference of C4/5 intervertebral disc was obvious after implantation of different height cages. (3) The overall intervertebral relative activity of C3-C7 decreased the most in the higher cage implantation height group, followed by the moderate cage implantation height group, and the overall intervertebral activity decreased least in the lower cage implantation height group. (4) It is suggested that the appropriate implantation height of the cage can make the cervical spine achieve immediate stability, and minimize the stress on the cage and cervical vertebra, so as to effectively avoid the cervical cage subsidence. [ABSTRACT FROM AUTHOR]

Introduction: Cervical hybrid surgery (HS) combines anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) to establish an individualized surgical plan for patients with multiple cervical disc degenerative diseases. In order to maintain the stability of the spine after HS, an external cervical collar is often used. However, there is still controversy regarding the importance of a cervical collar following surgery. This study aims to determine whether the cervical collar is effective and how long it should be worn after surgery. Methods: This is a randomized, single-center, prospective, parallel-controlled trial. Eligible participants will be selected according to the inclusion and exclusion criteria. The primary outcome is the neck disability index, which will be evaluated before surgery and at one week, 3 weeks, 6 weeks, 3 months, 6 months, and 12 months following surgery. The secondary outcomes consist of the Japanese Orthopedic Association Scores, MOS 36-item short-form health survey (SF-36), visual analog scale, Pittsburgh Sleep Quality Index (PSQI), Bazaz dysphagia scoring system, Falls Efficacy Scale, cervical collar satisfaction score, neck soft tissue assessment, and Braden Scale, as well as radiologic assessments for cervical lordosis, disc height of the operative levels, fusion rate, range of motion (ROM), and complications including anterior bone loss, prosthesis migration, and heterotopic ossification. The clinical and radiologic examinations were performed by investigators with no therapeutic relationship with the individual patient. All radiographs were examined by one independent radiologist. Ethics and dissemination: The results of this study will be published in peer-reviewed journals and presented at conferences. Upon completion of this trial, our findings could provide an appropriate cervical collar-wearing guideline for patients receiving HS. Trial registration: ChiCTR.org.cn ChiCTR2000033002. Registered on 2020–05-17. [ABSTRACT FROM AUTHOR]

Study Design: Cadaveric biomechanics study. Objective: Subchondral bone mineral density (sBMD) reflects the long-term mineralization and distribution of stress on joints. The use of 3-dimensional (3-D) methods to evaluate sBMD, including computed tomography osteoabsorptiometry (CT-OAM), enables the assessment of density distribution with emphasis on subchondral bone. This study sought to measure the sBMD of cervical endplates using CT-OAM and correlate it to mechanical implant subsidence in a cadaveric model. Methods: Fourteen fresh human cadaveric cervical spines were subjected to dynamic testing after single level discectomy and instrumentation using a PEEK interbody spacer. Specimens were imaged with CT 3 times: 1st) whole intact cervical spine, 2nd) after implantation, and 3 rd) after testing. These images were used to assess sBMD distributions using CT-OAM directly underneath the spacer. Subsidence was defined as the displacement of the device into the endplates. Results: The observed "failure mode" was consistently recorded as subsidence, with a mean of 0.45 ± 0.36 mm and 0.40 ± 0.18 mm for the C4-5 and C6-7 levels, respectively. There were no differences by level. The experimental cyclic test showed that denser endplates experienced less deformation under the same load. Conclusions: This study achieved its stated aim of validating the use of CT-OAM as a method to analyze the sBMD of the cervical endplates. Studies such as this are providing new information on available technology such as CT-OAM, providing new tools for clinicians treating spinal conditions in need of augmentation and stabilization via interbody devices. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cortical bone trajectory screw is a new type of spinal minimally invasive internal fixation technology. Compared with traditional pedicle screws, it has the characteristics of less trauma and strong pullout resistance, and has strong biomechanical properties for patients with osteoporosis. However, studies on the application of cortical bone trajectory screws combined with oblique lateral interbody fusion and fixation are still rare. OBJECTIVE: To evaluate the effect of oblique lateral interbody fusion combined with various fixation methods on stress distribution and range of motion of cage and L4-5 lower endplate by constructing three kinds of finite element models including oblique lateral interbody fusion (OLIF stand-alone) model, OLIF combined with bilateral pedicle screw (OLIF+BPS) model and OLIF combined with cortical bone trajectory screw (OLIF+CBT) model. METHODS: The CT images of adult lumbar spine were used to establish the three kinds of OLIF finite element models: OLIF stand alone, OLIF+BPS, and OLIF+CBT. Ansys workbench was used to simulate the application of six different motion loads of human body flexion and extension, left and right bending, and left and right rotation to calculate stress distribution and the changes in the range of motion of the lumbar spine of the cage and endplate of the three lumbar spine surgery models and to compare the effects of three surgical options on the biomechanical effects of the lumbar spine. RESULTS AND CONCLUSION: (1) The OLIF stand-alone model, OLIF+BPS model and OLIF+CBT model were constructed successfully. (2) In terms of range of motion, OLIF+CBT model presented no obvious difference with that of OLIF stand-alone model in flexion and extension, left and right lateral bending, and left and right rotation motions. (3) In flexion, extension, and lateral bending conditions, the maximum stress of cage of OLIF+CBT model was smaller than that of OLIF stand-alone model and slightly greater than that of OLIF+BPS model. When it came to rotating condition, the maximum stress of cage in OLIF+CBT model was bigger than that of two other models. (4) The maximum stress of the lower end plate of OLIF+CBT model was smaller than that of OLIF stand-alone model but slightly greater than that of OLIF+BPS model at various conditions. (4) It is concluded that OLIF combined with CBT fixation provides a good stable support for the vertebral body of the fusion segment on the premise of ensuring the mobility of the lumbar spine, and has a relatively good biomechanical effect. [ABSTRACT FROM AUTHOR]