Molecular mechanism of RBM14-mediated promotion of proliferation, migration, and invasion in osteosarcoma.

Background: Osteosarcoma (OS) is an exceptionally aggressive bone neoplasm that predominantly impacts the paediatric and adolescent population, exhibiting unfavourable prognosis. The importance of RNA binding motif protein 14 (RBM14) in the aetiology of OS is not well understood, despite its established involvement in several other types of cancer. Methods: In this study, we conducted an analysis of the expression profiles of RBM14 in cancer tissues and cell lines. To achieve this, we will utilised data obtained from various databases including The Cancer Genome Atlas Program (TCGA) project, The Genotype-Tissue Expression (GTEx) Project, Gene Expression Omnibus (GEO) database, and cancer cell line encyclopedia (CCLE) data. Furthermore, this study also aims to examine the effects of RBM14 on the proliferation, migration, and invasive properties of OS cells using cell functional gain and loss studies. In this study, we carried out an in-depth investigation to explore possible molecular pathways that underlie the regulation of the malignant phenotype found in OS by RBM14. This investigation involved integrating data from RBM14 overexpression, RBM14 knockdown RNA-seq experiments, and an array comprising 6,096 perturbed genes obtained from the Genetic Perturbation Similarity Analysis Database (GPSAdb). This research offers an opportunity to build a robust conceptual framework for the potential advancement of novel therapeutic approaches that are especially aimed at attacking OS. Results: RBM14 plays an active role in OS by significantly contributing to the enhancement of cellular proliferation, migration, and invasion. At the molecular level, it is probable that RBM14 exerts control over the malignant characteristics of OS through its modulation of the Hippo signalling system. Conclusions: The above-mentioned findings underscore the significant importance of RBM14 as an intriguing target for therapy for the mitigation and management of OS. This particular protein holds an excellent opportunity for the development of novel and efficacious therapeutic approaches that possess the potential to yield favorable results for patients affected with OS.

Effect of Insertional Direction of Pedicle Screw on Screw Loosening: A Biomechanical Study on Synthetic Bone Vertebra under a Physiology-like Load.

OBJECTIVES: It is now understood that pedicle screw loosening at the implant-bone interface can lead to poor screw-bone interface purchase and decreased fixation stability. Previous biomechanical tests used cadaveric vertebrae and pull-out or torque loads to assess the effect of the insertional direction of pedicle screws on screw loosening. However, these tests faced challenges in matching biomechanical differences among specimens and simulating in vivo loads applied on pedicle screws. This study aimed to evaluate the effect of the insertional direction of pedicle screws on screw loosening using tension-compression-bending loads and synthetic bone vertebrae. METHODS: Polyaxial pedicle screws were inserted into nine synthetic bone vertebrae in three directions (three samples per group): cranial, parallel, and caudad (-10°, 0°, +10° of the pedicle screw rod to the upper plane of the vertebra, respectively). Pedicle screws in the vertebrae were loaded using a polyethylene block connected to a material testing machine. Tension-compression-bending loads (100N-250N) with 30,000 cycles were applied to the pedicle screws, and displacements were recorded and then cycle-displacement curve was drawn based on cycle number. Micro-CT scans were performed on the vertebrae after removing the pedicle screws to obtain images of the screw hole, and the screw hole volume was measured using imaging analysis software. Direct comparison of displacements was conducted via cycle-displacement curve. Screw hole volume was analyzed using analysis of variance. The correlation between the displacement, screw hole volume and the direction of pedicle screw was assessed by Spearman correlation analysis. RESULTS: The smallest displacements were observed in the caudad group, followed by the parallel and cranial groups. The caudad group had the smallest screw hole volume (p < 0.001 and p = 0.009 compared to the cranial and parallel groups, respectively), while the volume in the parallel group was greater than that in the cranial group (p = 0.003). Correlation analysis revealed that the insertional direction of the pedicle screw was associated with the displacement (p = -0.949, p < 0.001) and screw hole volume (p = -0.944, p < 0.001). CONCLUSION: Strong correlations were found between the insertional direction of the pedicle screw and relevant parameters, including displacement and screw hole volume. Pedicle screw insertion in the caudad direction resulted in the least pedicle screw loosening.

An in Vivo, Three-Dimensional (3D), Functional Centers of Rotation of the Healthy Cervical Spine.

OBJECTIVE: This study examined cervical center of rotation (COR) positions in 7 postures using validated cone beam computed tomography (CBCT) combined with 3D-3D registration in healthy volunteers. METHODS: CBCT scans were performed on 20 healthy volunteers in 7 functional positions, constructing a three-dimensional (3D) model. Images were registered to the neutral position using 3D-3D registration, allowing analysis of kinematic differences and rotational axes. COR measurements were obtained for each segment (C2/3 to C6/7) in each posture. RESULTS: The CORs of C2/3 to C6/7 were predominantly posterior (-5.3 ± 3.8 ∼ -0.6 ± 1.2 mm) and superior (16.5 ± 6.0 ∼ 23.6 ± 3.2 mm) to the intervertebral disc's geometric center (GC) in flexion and extension. However, the C4/5 segment's COR was anterior to the GC (2.0 ± 9.8 mm) during flexion and close to it in the right-left direction. During left-right twisting, the CORs of C2/3-C6/7 were posterior (-21.8 ± 10.5 ∼-0.9 ± 0.8 mm) and superior (3.1 ± 7.5 ∼23.2 ± 3.6 mm) to the GCs in anterior-posterior and superior-inferior directions, without consistent right-left directionality. During left-right bending, each segment's COR was predominantly posterior (-25.2 ± 13.1 ∼-6.5 ± 9.9 mm) and superior (0.3 ± 12.5 ∼12.1 ± 5.1 mm) to the GC in anterior-posterior and superior-inferior directions, except for the C2/3 segment, located inferiorly (-5.9 ± 4.1 mm) in left bending. The right-left COR position varied across segments. CONCLUSIONS: Our findings reveal segment-specific and posture-dependent COR variations. Notably, the CORs of C3/4, C4/5, and C5/6 consistently align near the intervertebral disc's GC at different postures, supporting their suitability for total disc replacement surgery within the C3/4 to C5/6 segments.

DLP fabrication of HA scaffold with customized porous structures to regulate immune microenvironment and macrophage polarization for enhancing bone regeneration.

The immune microenvironment plays a pivotal role in osteoanagenesis. Biomaterials can modulate osteogenic efficacy by inducing specific local immune reactions. As 3D-printing technology advances, digital light projection printing has emerged as a promising method for creating large scale, high-precision biomaterial scaffolds. By adjusting the solid content and the sintering conditions during printing, the pore size of biomaterials can be meticulously controlled. Yet, the systematic influence of pore size on the immune microenvironment remains uncharted. We fabricated 3D-printed hydroxyapatite bioceramic scaffolds with three distinct pore sizes: 400 µm, 600 µm, and 800 µm. Our study revealed that scaffolds with a pore size of 600 µm promote macrophage M2 polarization, which is achieved by upregulating interferon-beta and HIF-1α production. When these materials were implanted subcutaneously in rats and within rabbit skulls, we observed that the 600 µm scaffolds notably improved the long-term inflammatory response, fostered vascular proliferation, and augmented new bone growth. This research paves the way for innovative therapeutic strategies for treating large segmental bone defects in clinical settings.

ATG9A as a potential diagnostic marker of intervertebral disc degeneration: Inferences from experiments and bioinformatics analysis incorporating sc-RNA-seq data.

BACKGROUND: Disfunctional autophagy plays a pivotal role in Intervertebral Disc Degeneration (IDD) progression. however, the connection between Autophagy-related gene 9A (ATG9A) and IDD has not been reported. METHODS: Firstly, transcriptome datasets from the GEO and Autophagy-related genes (ARGs) from GeneCards were carried out using R. Following this, IDD-specific signature genes were identified through methods such as least absolute shrinkage and selection operator (LASSO), random forest (RF), and support vector machine (SVM) analyses. Validation of these findings proceeded through in vitro experiments, evaluation of independent datasets, and analysis of receiver operating characteristic (ROC) curves. Subsequent steps incorporated co-expression analysis, Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, Gene Set Enrichment Analysis (GSEA), and construction of competing endogenous RNA (ceRNA) network. The final section established the correlation between immune cell infiltration, ATG9A, and IDD utilizing the CIBERSORT algorithm and single-cell RNA (scRNA) sequencing data. RESULTS: Research identified 87 differentially expressed genes, with only ATG9A noted as an IDD signature gene. Analysis of in vitro experiments and independent datasets uncovered a decrease in ATG9A expression within the degeneration group. The area under the curve (AUC) of ATG9A exceeded 0.8 following ROC analysis. Furthermore, immune cell infiltration and scRNA sequencing data analysis elucidated the substantial role of immune cells in IDD progression. A ceRNA network was constructed, centered around ATG9A, included 4 miRNAs and 22 lncRNAs. CONCLUSION: ATG9A was identified as a diagnostic gene for IDD, indicating its viability as a effective target for therapy disease.

Improvement of Pulmonary Function and Reconstructed 3-Dimensional Lung Volume After Halo-Pelvic Traction Combined With Posterior Correction for Severe Rigid Spinal Scoliosis: A Multicenter Study.

BACKGROUND AND OBJECTIVES: Severe rigid spinal scoliosis (SRSS) leads to severe restrictive ventilation dysfunction. Currently, the reports about the influence of preoperative halo-pelvic traction (HPT) combined with correction surgery on pulmonary function in patients with SRSS were relatively few. This study aims to investigate (1) the influence of preoperative HPT on lung volume and pulmonary function, (2) the further influence of the following correction surgery on lung volume and pulmonary function, and (3) the relationship among deformity correction, pulmonary function test outcomes, and computed tomography-based lung volume. METHODS: A total of 135 patients with SRSS who underwent preoperative HPT and followed low-grade osteotomy correction surgery were reviewed. Spinal parameters, including proximal thoracic curve, main thoracic curve (MTC), lumbar curve, coronal balance, thoracic kyphosis, lumbar lordosis, sagittal vertical axis, pulmonary function test outcomes (forced vital capacity [FVC], the percentage of predicted forced vital capacity [FVC%], forced expiratory volume in 1 second [FEV1], total lung capacity [TLC]), and lung volume (Vin), were analyzed before, after HPT and at the final follow-up, respectively. RESULTS: The mean FVC, FVC%, FEV1, and TLC increased from 1.67 L, 51.13%, 1.47 L, and 2.37 L to 1.95 L, 64.35%, 1.75 L, and 2.78 L, respectively, after HPT and further improved to 2.22 L, 72.14%, 1.95 L, and 3.15 L, respectively, at the final follow-up. The mean Vin increased from 1.98 L to 2.42 L after traction and further increased to 2.76 L at the final follow-up. The variation of MTC was correlated with the improvement of FVC (r = 0.429, P = .026), FVC% (r = 0.401, P = .038), FEV1 (r = 0.340, P = .043), and TLC (r = 0.421, P = .029) and the variation of Vin (r = 0.425, P = .015) before HPT and after surgery. CONCLUSION: Preoperative HPT can improve preoperative pulmonary function and enhance the preoperative lung volume. There were significant correlations among the variations of MTC, pulmonary function indexes, and lung volume before HPT and after surgery in patients with SRSS.

Clinical efficacy and imaging analysis for the surgical treatment of thoracolumbar infections in elderly patients: a retrospective study.

Few reports have been conducted to comparing surgical results and safety evaluations between the different types of infections in geriatric patients with thoracolumbar infections. The aim of this study is to investigate the safety and efficacy of surgical treatment for thoracolumbar infections in elderly patients. 21 patients with pyogenic spondylodiscitis (PS) and 26 patients with tuberculous spondylodiscitis (TS) were enrolled in the study. All patients were treated using one-stage posterior debridement, decompression, and pedicle screw fixation. Comparison of operative safety parameters between the two groups. Clinical efficacy was evaluated using visual analogue scale (VAS) score, the American Spinal Injury Association (ASIA) grade, the short form (SF)-36 survey and Oswestry disability index (ODI) to determine patient quality of life pre- and post-operatively. Hospitalisation and intensive care unit duration in the PS group were significantly shorter than in the TS group (P < 0.05). The total incidence of post-operative complications for both groups was 44.7%. More complications occurred in the TS group, but the difference was not significant. The scores of VAS, ODI and SF-36 of all 47 patients were significantly improved compared with those before operation.The VAS and SF-36 scores (physical component) were significantly better in the PS group 6 months post-operatively, and the SF-36 (mental component) scores were significantly better in the PS group at the 1-year follow-up. Neurological status in both groups improved post-operatively, and 83% of patients reported satisfactory results based on the modified MacNab standard. Imaging results showed that bone graft fusion improved in both groups at 6 months, 1 year and at the final follow-up. One-stage posterior debridement, decompression, interbody fusion, and internal fixation can be considered a safe and effective method of treating spinal infections in the elderly. This method can improve nerve function, reconstruct spinal stability, and enhance the quality of life of elderly patients. Both PS and TS who underwent surgery achieve similar clinical and radiological results.

Osteotomized debridement versus curetted debridement in posterior approach in treating thoracolumbar tuberculosis: a comparative study.

PURPOSE: This study aimed to compare osteotomized debridement (OD) with traditional curetted debridement (CD) in treating thoracolumbar tuberculosis (TB). METHODS: A total of 188 patients were diagnosed with active thoracolumbar TB and underwent one-stage posterior surgery at our institution. Of the 188 patients, 85 patients were treated with OD, and 103 patients were treated with traditional CD. The patient information, laboratory results, imaging findings, and clinical effectiveness were, respectively, compared between the two groups. RESULTS: Group OD consumed less operation time and blood loss than group CD (P < 0.05 for both values). No significant difference in hospitalization time was found between the two groups (P > 0.05). The values of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in both groups returned to the normal range within one month postoperatively. All patients had significant improvement in visual analog scale (VAS) and oswestry disability index (ODI) postoperatively. The mean fusion time in group OD was shorter than that in group CD (P < 0.05). There was no statistically significant difference in preoperative kyphotic angle between the two groups (P > 0.05), but group OD showed less correction loss than group CD at the final follow-up (P < 0.05). The rate of recurrence and surgery-related complications in group OD was lower than group CD. CONCLUSIONS: Posterior OD, reconstruction with titanium mesh cages (TMCs), and instrumentation is feasible and effective in treating thoracolumbar TB. Compared with the traditional CD, OD can achieve radical lesion removal, more effective kyphosis correction, lower recurrence rate, and fewer complications.

Validation and application of a novel in vivo cervical spine kinematics analysis technique.

To validate the accuracy of Cone beam computed tomography (CBCT) cervical spine modeling with three dimensional (3D)-3D registration for in vivo measurements of cervical spine kinematics. CBCT model accuracy was validated by superimposition with computed tomography (CT) models in 10 healthy young adults, and then cervical vertebrae were registered in six end positions of functional movements, versus a neutral position, in 5 healthy young adults. Registration errors and six degrees of freedom (6-DOF) kinematics were calculated and reported. Relative to CT models, mean deviations of the CBCT models were < 0.6 mm. Mean registration errors between end positions and the reference neutral position were < 0.7 mm. During flexion-extension (F-E), the translation in the three directions was small, mostly < 1 mm, with coupled LB and AR both < 1°. During lateral bending (LB), the bending was distributed roughly evenly, with coupled axial rotation (AR) opposite to the LB at C1-C2, and minimal coupled F-E. During AR, most of the rotation occurred in the C1-C2 segment (29.93 ± 7.19° in left twist and 31.38 ± 8.49° in right twist) and coupled LB was observed in the direction opposite to that of the AR. Model matching demonstrated submillimeter accuracy in cervical spine kinematics data. The presently evaluated low-radiation-dose CBCT technique can be used to measure 3D spine kinematics in vivo across functional F-E, AR, and LB positions, which has been especially challenging for the upper cervical spine.

In vivo 3-Dimensional Kinematics Study of the Healthy Cervical Spine Based on CBCT Combined with 3D-3D Registration Technology.

STUDY DESIGN: A cervical biomechanical study. OBJECTIVE: We sought to demonstrate the three-dimensional (3D) intervertebral motion characteristics of the cervical spine in healthy volunteers using cone beam computed tomography (CBCT) combined with 3D-3D registration technology. SUMMARY OF BACKGROUND DATA: No previous studies have used CBCT combined with 3D-3D registration technology to successfully documented in vivo 3D intervertebral six-degrees-of-freedom (6-DOF) motions of the cervical spine. METHODS: Twenty healthy subjects underwent cervical (C1-C7) CBCT scans in seven functional positions. Segmented 3D vertebral body models were established according to the cervical CBCT images. A 3D-to-3D registration was then performed for each vertebral body in the different positions to calculate the 3D segmental motion characteristics in vivo. RESULTS: During flexion-extension, the range-of-motion (ROM) of C1-C2 and C4-C5 was significantly greater than the other segments. The average coupled axial rotation and lateral bending of each segment were between 0.6° and 3.2°. The average coupling translations in all directions were between 0.2 and 2.1 mm. During axial rotation, the ROM of C1-C2 was 65.8 ±â€Š5.9°, which accounted for approximately 70% of all axial rotation. The motion and displacement of C1-C2 coupled lateral bending were 11.4 ±â€Š5.2° and 8.3 ±â€Š1.9 mm, respectively. During lateral bending, the ROM of C3-C4 was significantly greater than C1-C2, C5-C6, and C6-C7. The coupled axial rotation of C1-C2 was 34.4 ±â€Š8.1°, and the coupled lateral translation was 3.8 ±â€Š0.5 mm. The coupled superoinferior and anteroposterior translation of each cervical segment were between 0.1 and 0.6 mm. CONCLUSION: CBCT combined with 3D-3D registration was used to accurately measure and record the ROMs of lateral bending, axial rotation, and flexion-extension in cervical vertebrae under physiological-load conditions. Our findings may contribute to the diagnosis of cervical spinal disease, the development of new surgical techniques, and the restoration of normal, cervical segmental movement.Level of Evidence: 3.

Motion characteristics of the lower lumbar spine in individuals with different pelvic incidence: An in vivo biomechanical study.

BACKGROUND: Pelvic incidence is the quantification of the pelvis anatomical shape which has significant effect on the occurrence of various lumbar degenerative diseases. The aim of this study was to measure the in vivo dynamic motion characteristics of the lower lumbar spine in people with different pelvic incidence. METHODS: A total of 55 volunteers were included in the study. The participants were devided into 3 groups (A: pelvic incidence≤40°, B: 40° < pelvic incidence <60° and C: pelvic incidence ≥60°). The L3-S1 vertebrae of each subject was MRI scanned to construct 3D models. The lumbar spine was then imaged using a dual fluoroscopic imaging system as the subject performed physiological position. The 3D vertebral models and the fluoroscopic images were used to reproduce the in vivo vertebral positions along the motion path. The relative translations and rotations of each motion segment were analyzed. FINDINGS: At the L5-S1 segment, the primary ranges of motion for left-right axial rotation and flexion-extension of the patients with large pelvic incidence (3.28° ± 0.79°, 7.56° ± 1.81°) were significantly larger than normal pelvic incidence (2.61° ± 1.01°, 6.57° ± 2.18°) and small pelvic incidence (2.00° ± 0.60°, 5.83° ± 1.67°). INTERPRETATION: The anatomic variable pelvic incidence is associated with the ranges of motion in lower lumbar vertebrae, especially in the L4-5 and L5-S1 segments.

A Technique for the In Vivo Study of Three-dimensional Cervical Segmental Motion Characteristics After Anterior Screw Fixation for Odontoid Process Fractures.

STUDY DESIGN: Kinematics of the cervical spine was investigated using cone beam computed tomography (CBCT) images combined with three dimensions to three dimensions (3D-3D) registration technology in patients after anterior odontoid screw fixation (AOSF) surgery. OBJECTIVE: The aim of this study was to investigate in vivo 3D cervical motion characteristics of patients who had undergone AOSF surgeries. SUMMARY OF BACKGROUND DATA: AOSF surgery is a classic surgical method for the treatment of odontoid fracture, but there are few studies that investigated its effect on in vivo biomechanics of the cervical spine. Postoperative biomechanical characters of the atlantoaxial joint (C1-C2) and the caudal adjacent segment (C2-C3) have yet to be clarified. METHODS: The study involved 14 patients subjected to a procedure of AOSF with lag screw. Subjects were matched with 14 healthy controls. All subjects underwent CBCT scanning of the cervical spine under seven functional positions. A 3D-3D registration was performed for each vertebra at each functional position to calculate the segmental motion characteristics. The ranges of motion (ROMs) of the C1-C2, C2-C3, and the overall cervical spine (C1-C7) for each of the functional positions were determined. RESULTS: The ROMs of the AOSF group were significantly (P < 0.05) smaller than the control group in flexion-extension positions for the C1-C2 (7.0°vs.11.0°), C2-C3 (3.7°vs.6.7°) and C1-C7 (43.3°vs.54.4°). The twisting ROM of the C1-C2 was 39.3° in the AOSF group and 65.7° in the control (P < 0.05), the bending ROM of the C2-C3 was 2.8° in the AOSF group and 8.9° in the control (P < 0.05). The twisting ROM of C1-C7 segment was 63.2° for the AOSF and 98.1° for the healthy control groups (P < 0.05). CONCLUSION: Although AOSF surgery reduced the flexion-extension ROMs of all investigated spinal segments, additionally, it reduced twisting ROMs of C1-C2 and C1-C7, but only lateral bending ROM of C2-C3, when compared with the control group. The data implied that the AOSF surgery would result in different biomechanics changes in the atlantoaxial segment and caudal adjacent segment. Longer-term follow-up studies of larger patient cohorts are necessary to evaluate the clinical outcomes of patients after the AOSF surgery.Level of Evidence: 3.

Effect of facet-joint degeneration on the in vivo motion of the lower lumbar spine.

OBJECTIVE: This research studied the in vivo motion characteristics of the L3-S1 lumbar spine with facet-joint degeneration during functional activities. METHODS: Thirteen male and 21 female patients with facet-joint degeneration at the L3-S1 spinal region were included in the study. The L3-S1 lumbar segments of all the patients were divided into 3 groups according to the degree of facet-joints degeneration (mild, moderate, or severe). The ranges of motion (ROM) of the vertebrae were analyzed using a combination of computed tomography and dual fluoroscopic imaging techniques. During functional postures, the ROMs were compared between the 3 groups at each spinal level (L3-L4, L4-L5, and L5-S1). RESULTS: At L3-L4 level, the primary rotations between the mild and moderate groups during left-right twisting activity were significantly different. At L4-L5 level, the primary rotation of the moderate group was significantly higher than the other groups during flexion-extension. During left-right bending activities, a significant difference was observed only between the moderate and severe groups. At L5-S1 level, the rotation of the moderate group was significantly higher than the mild group during left-right bending activity. CONCLUSIONS: Degeneration of the facet joint alters the ROMs of the lumbar spine. As the degree of facet-joint degeneration increased, the ROMs of the lumbar vertebra that had initially increased declined. However, when there was severe facet-joint degeneration, the ROMs of the lumbar spine declined to levels comparative to the moderate group. The relationship between the stability of the lumbar vertebra and the degree of facet-joint degeneration requires further study.

Evaluation of MRI and CT parameters to analyze the correlation between disc and facet joint degeneration in the lumbar three-joint complex.

Lumbar 3-joint complex degeneration is a multifactorial, pathological process. Previous studies included insufficient quantitative analyses to prove the relationship between disc degeneration and facet joint osteoarthritis (OA). We assessed the correlation between intervertebral disc and lumbar facet joint degeneration using computed tomography (CT) and magnetic resonance imaging (MRI) parameters.A total of 152 participants who underwent conventional MRI and CT in the clinostat position were included in this study. The presence of lumbar disc degeneration was identified using the Pfirrmann grading system, and the presence of lumbar facet joint degeneration was identified using the Weishaupt grading system. Facet tropism was defined as a divergence more than 7° between the facet joint angles of both sides at the same segment. The intervertebral disc heights were also measured.Most facet joint OA probably appeared at the segment with intervertebral disc degeneration of more than grade III. Facet joint OA was significantly exacerbated with the progression of disc degeneration grade. The intervertebral height significantly decreased with the progression of facet joint degeneration grades, except for grades 0 and 1.Our current study found that each individual joint degeneration influences the other 2 in the lumbar 3-joint complex. Facet tropism was significantly associated with lumbar disc degeneration. Narrowing of the intervertebral disc height probably aggravates the facet joint degeneration further at the same level.

CSN5 controls the growth of osteosarcoma via modulating the EGFR/PI3K/Akt axis.

CSN5, a critical subunit of the constitutive photomorphogenesis 9 (COP9) signalosome (CSN), functions as a potential tumor promoter in various cancers. However, the biological functions and clinical significance of CSN5 in osteosarcoma (OS) remains unclear. Here, we report that OS tumors overexpressed CSN5 compared with normal bone tissues, and CSN5 overexpression was obviously associated with the malignant phenotype and poor prognosis in patients with OS. In addition, high CSN5 expression significantly promoted the growth of OS cells, whereas CSN5 silence suppressed the tumorigenicity of OS cells. Furthermore, we found PI3K/Akt signaling pathway contributed to the effects of CSN5 in OS cells, and blocking the Akt pathway significantly inhibited the actions of CSN5. Mechanistically, we demonstrate that CSN5 positively regulated EGFR stability through reducing the levels of EGFR ubiquitination, thereby activating the PI3K/Akt signaling pathway in OS cells. Moreover, our results shown that the oncogenic effects of CSN5 on OS cells were EGFR dependent. Thus, CSN5 has a central role in regulating diverse aspects of the pathogenesis of OS, which could be a potential diagnostic and therapeutic target for OS.

In vivo dynamic motion characteristics of the lower lumbar spine: L4-5 lumbar degenerative disc diseases undergoing unilateral or bilateral pedicle screw fixation combined with TLIF.

OBJECTIVE: To evaluate the short-term in vivo dynamic motion characteristics of the lower lumbar spine (L3-S1) after unilateral pedicle screw fixation (UPSF) or bilateral pedicle screw fixation (BPSF) combined with TLIF for treatment of L4-5 lumbar degenerative disc diseases (DDD). METHODS: Twenty-eight patients were recruited (13 UPSF, 15 BPSF). Each patient was CT-scanned to construct 3D models of the L3-S1 vertebrae. The dual fluoroscopic imaging system (DFIS) was then used to image the lumbar spine while the patient performed seven functional activities (upright standing, maximum extension, flexion, left-right twist, and left-right bend). The in vivo vertebral positions were reproduced using the 3D vertebral models and DFIS images. The ranges of motion (ROMs) of L3-4, L4-5, and L5-S1 segments were analyzed. RESULTS: At the index L4-5 segment, the primary ROM of left-right twist of the UPSF group (2.11 ± 0.52°) was significantly larger (p = 0.000) than the BPSF group (0.73 ± 0.32°). At the proximal adjacent L3-4 segment, the primary ROMs of left-right twist, and left-right bend of the UPSF group (2.16 ± 0.73°, 2.28 ± 1.03°) were significantly less (p = 0.003, 0.023) than the BPSF group (3.17 ± 0.88, 3.12 ± 1.04°), respectively. However, at distal adjacent L5-S1 segment, no significant difference was found between the two groups during all activities. CONCLUSIONS: The ROM in left-right twisting of UPSF group was significantly larger compared with BPSF group at the index level in the short term. The UPSF has less impact on the cranial adjacent level (L3-4) in left-right twisting and bending activities compared to the BPSF. The data implied that the UPSE and BPSF combined with TLIF would result in different biomechanics in the index and cranial adjacent segment biomechanics. Long-term follow-up studies are necessary to compare the clinical outcomes of the two surgeries.

A rare case of giant osteoblastoma of the sacrum.

BACKGROUND: An osteoblastoma is a rare benign bone tumor characterized by formation of osteoid tissue and primitive bone and occurs more often in men than in women. They are often secondary to an osteoid osteoma and can be located at any site on the skeleton. Lesions generally involve the posterior elements of the spine, such as the pedicle and the lamina. CASE PRESENTATION: This study reports the case of a 25-year-old female who suffered from an osteoblastoma of the right sacrum with repeated swelling and pain in the right lumbosacral region for approximately 6 months. Computed tomography (CT) and magnetic resonance imaging (MRI) of the pelvis revealed a segmented, expansive, multiseptate lesion. Resection with wide margins was performed and a huge cavity of approximately 15â€¯× 8â€¯× 4.4 cm in the right sacrum and pelvis was formed after complete curettage of the tumor. The pathological analysis of the resected tissue was consistent with a benign osteoblastoma. A follow-up was performed 2 years later and the patient was eventually relieved of the pain, the mobility of the right leg was improved and the CT scan demonstrated no evidence of recurrence. CONCLUSION: Osteoblastomas most commonly occur in the spine but rarely also in the sacrum. Large core needle biopsies play an important role in the diagnostics. Intralesional surgery can be performed for treatment of osteoblastomas.

Lumbar spinal canal osteosarcoma: A case report.

RATIONALE: Osteosarcoma is a rare neoplasm in the lumbar spine. Although osteosarcoma can arise in any portion of the skeleton, it very rarely arises in the spinal canal, which accounts for <0.1% of all cases of adult sarcomas. Here, we describe a case of osteosarcoma arising in the L4-5 spinal canal. PATIENT CONCERNS: The present report describes the case of a 55-year-old female patient with osteosarcoma of the L4-5 spinal canal. DIAGNOSES: The patient was initially diagnosed with lumbar spinal stenosis and underwent lumbar fusion at a local hospital. At the 4-month follow-up, the patient reported a marked increase in numbness and pain in the lumbar region and lower limbs. Based on magnetic resonance imaging, we diagnosed a postoperative infectious lesion of the lumbar spine. INTERVENTIONS: The patient underwent surgery for complete removal of the mass lesion. The mass measured 3 × 2.5 × 0.7 cm in size and was located in the L4-5 spinal canal. OUTCOMES: Based on histological and immunohistochemical findings, the diagnosis of osteosarcoma was confirmed by an expert pathology consultant. The patient then received chemotherapy. Postoperative follow-up at 6 months revealed no evidence of recurrent disease or residual side effects from therapy. LESSONS: Osteosarcoma in the L4-5 spinal canal is extremely rare and very difficult to distinguish histologically from benign nervous and fibrous tissue. This is a very valuable case, which highlights the need for orthopedic surgeons to consider this when diagnosing patients with spinal tumors.

Correlation between the sagittal spinopelvic alignment and degenerative lumbar spondylolisthesis: a retrospective study.

BACKGROUND: Pain and disability associated with degenerative lumbar spondylolisthesis (DLS) results in significant burden on both the patients' quality of life and healthcare costs. Currently, there is controversy regarding the specificity of spinopelvic measures of sagittal plane alignment with respect to DLS. Moreover, the correlation among spinopelvic parameters of sagittal plane alignment remains to be clarified. Our aim in this study was to compare these measurements between patients with single-segment DLS at L5 and a control group with no history of DLS. METHODS: Our study group was formed of 132 patients who underwent full length lateral view radiographs of the spine in a relaxed standing posture. Among these, DLS at L5 was identified in 72 patients, forming the DLS group, with no radiographic evidence of lumbar spine disease in the remaining 60 patients, forming the control group. The patient and control groups were balanced with regard to age and sex distribution. The following spinopelvic parameters of sagittal plane alignment were measured: angle of incidence (PI) and tilt (PT) of the pelvis; sacral slope (SS); thoracic kyphosis (TK); lumbar lordosis (LL); and the spinal sagittal vertical axis (SVA). The Meyerding grade of L5 slippage was quantified for each patient in the DLS group. RESULTS: Measures of TK, PI, SS, and LL were significantly greater in the DLS than control group (P <  0.05), with no between-group difference in SVA and PT. In the DLS group, the grade of L5 slippage correlated with SS (r = 0.873, P <  0.0001), PI (r = 0.791, P <  0.0001) and LL (r = 0.790, P <  0.0001). Moreover, the measurement for SS correlated more strongly with the PI (r = 0.94, P <  0.01) than the LL (r = 0.69, P <  0.01). CONCLUSION: Measurements of SS, PI, and LL were specifically associated with DLS, with measurements correlating positively with the grade of slippage.

Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion for the Treatment of Low Lumbar Degenerative Disc Diseases: Analysis of Clinical and Radiographic Results.

OBJECTIVE: To compare the clinical and radiographic results of unilateral pedicle screw fixation (UPSF) and bilateral pedicle screw fixation (BPSF) after unilateral transforaminal lumbar interbody fusion (TLIF) for the treatment of lumbar degenerative disc diseases (DDDs). METHODS: A total of 63 patients who underwent UPSF or BPSF combined with unilateral TLIF at L4-L5 or L5-S1 in our hospital between 2014 and 2016 were included in this analysis. The perioperative outcomes and radiographic results were recorded at preoperative and postoperative follow-up. Fusion rates were determined according to the Bridwell-Lenke grading system. Clinical outcomes were evaluated using the visual analog scale, Oswestry Disability Index, and lumbar Japanese Orthopedic Association score. RESULTS: According to the perioperative assessment, the duration of operation, intraoperative and postoperative blood loss, duration of pain medication use, and hospital costs were significantly (P < 0.0001) lower in the UPSF group compared with the BPSF group. After a mean follow-up of 24 months, both the UPSF and BPSF groups showed significantly (P < 0.05) maintained disc height and segmental lordosis of the surgical segment and achieved similar clinical outcomes at the final postoperative follow-up. The impact on the cranial adjacent vertebral level was significantly (P < 0.05) less in the UPSF group than the BPSF group in the short term. CONCLUSIONS: UPSF techniques with TLIF can attain similar clinical efficiency as BPSF techniques in treating single-level low lumbar DDD, but with fewer surgical injuries and at lower cost. BPSF with TLIF likely causes more degeneration at the cranial adjacent segment compared with UPSF techniques. The long-term results require more study.