Zinc-energized dynamic hydrogel accelerates bone regeneration via potentiating the coupling of angiogenesis and osteogenesis.

Insufficient initial vascularization plays a pivotal role in the ineffectiveness of bone biomaterials for treating bone defects. Consequently, enhancing the angiogenic properties of bone repair biomaterials holds immense importance in augmenting the efficacy of bone regeneration. In this context, we have successfully engineered a composite hydrogel capable of promoting vascularization in the process of bone regeneration. To achieve this, the researchers first prepared an aminated bioactive glass containing zinc ions (AZnBg), and hyaluronic acid contains aldehyde groups (HA-CHO). The composite hydrogel was formed by combining AZnBg with gelatin methacryloyl (GelMA) and HA-CHO through Schiff base bonding. This composite hydrogel has good biocompatibility. In addition, the composite hydrogel exhibited significant osteoinductive activity, promoting the activity of ALP, the formation of calcium nodules, and the expression of osteogenic genes. Notably, the hydrogel also promoted umbilical vein endothelial cell migration as well as tube formation by releasing zinc ions. The results of in vivo study demonstrated that implantation of the composite hydrogel in the bone defect of the distal femur of rats could effectively stimulate bone generation and the development of new blood vessels, thus accelerating the bone healing process. In conclusion, the combining zinc-containing bioactive glass with hydrogels can effectively promote bone growth and angiogenesis, making it a viable option for the repair of critical-sized bone defects.

Capturing cerium ions via hydrogel microspheres promotes vascularization for bone regeneration.

The rational design of multifunctional biomaterials with hierarchical porous structure and on-demand biological activity is of great consequence for bone tissue engineering (BTE) in the contemporary world. The advanced combination of trace element cerium ions (Ce3+) with bone repair materials makes the composite material capable of promoting angiogenesis and enhancing osteoblast activity. Herein, a living and phosphorylated injectable porous hydrogel microsphere (P-GelMA-Ce@BMSCs) is constructed by microfluidic technology and coordination reaction with metal ion ligands while loaded with exogenous BMSCs. Exogenous stem cells can adhere to and proliferate on hydrogel microspheres, thus promoting cell-extracellular matrix (ECM) and cell-cell interactions. The active ingredient Ce3+ promotes the proliferation, osteogenic differentiation of rat BMSCs, and angiogenesis of endotheliocytes by promoting mineral deposition, osteogenic gene expression, and VEGF secretion. The enhancement of osteogenesis and improvement of angiogenesis of the P-GelMA-Ce scaffold is mainly associated with the activation of the Wnt/ß-catenin pathway. This study could provide novel and meaningful insights for treating bone defects with biofunctional materials on the basis of metal ions.

A Self-Adaptive Biomimetic Periosteum Employing Nitric Oxide Release for Augmenting Angiogenesis in Bone Defect Regeneration.

The periosteum plays a vital role in the regeneration of critical-size bone defects and highly comminuted fractures, promoting the differentiation of osteoblasts, accelerating the reconstruction of the vascular network, and guiding bone tissue regeneration. However, the materials loaded with exogenous growth factors are limited by the release and activity of the elements. Therefore, the material structure must be carefully designed for the periosteal function. Here, a self-adaptive biomimetic periosteum strategy is proposed, which is a novel interpenetrating double network hydrogel consisting of diselenide-containing gelatin and calcium alginate (modified natural collagen and polysaccharide) to enhance the stability, anti-swelling, and delayed degradation of the hydrogel. The diselenide bond continuously releases nitric oxide (NO) by metabolizing endogenous nitrosated thiols (RSNO), activates the nitric oxide-cycle guanosine monophosphate (NO-cGMP) signal pathway, coordinates the coupling effect of angiogenesis and osteogenesis, and accelerates the repair of bone defects. This self-adaptive biomimetic periosteum with the interpenetrating double network structure formed by the diselenide-containing gelatin and calcium alginate has been proven to be safe and effective in repairing critical-size bone defects and is expected to provide a promising strategy for solving clinical problems.

Research progress of vascularization strategies of tissue-engineered bone.

The bone defect caused by fracture, bone tumor, infection, and other causes is not only a problematic point in clinical treatment but also one of the hot issues in current research. The development of bone tissue engineering provides a new way to repair bone defects. Many animal experimental and rising clinical application studies have shown their excellent application prospects. The construction of rapid vascularization of tissue-engineered bone is the main bottleneck and critical factor in repairing bone defects. The rapid establishment of vascular networks early after biomaterial implantation can provide sufficient nutrients and transport metabolites. If the slow formation of the local vascular network results in a lack of blood supply, the osteogenesis process will be delayed or even unable to form new bone. The researchers modified the scaffold material by changing the physical and chemical properties of the scaffold material, loading the growth factor sustained release system, and combining it with trace elements so that it can promote early angiogenesis in the process of induced bone regeneration, which is beneficial to the whole process of bone regeneration. This article reviews the local vascular microenvironment in the process of bone defect repair and the current methods of improving scaffold materials and promoting vascularization.

Bone Cement and Pedicle Screw for the Treatment of Spinal Tumors with Spinal Cord Compression and Posterior Wall Defects.

OBJECTIVE: To compare the safety and efficacy of posterior internal fixation with open vertebroplasty (VP) and posterior internal fixation with open kyphoplasty (KP) in the treatment of metastatic epidural spinal cord compression (MESCC) with posterior wall destruction. METHODS: This retrospective study, conducted between January 2016 and May 2019, equally divided 60 patients with MESCC and posterior wall destruction into two groups based on the surgical method: open vertebroplasty with pedicle screw fixation (VP group) and open kyphoplasty with pedicle screw fixation (KP group). Visual analogue scale (VAS), SF-36 scores, middle vertebral height (MVH), and posterior vertebral height (PVH) were evaluated for the two groups preoperatively, postoperatively, and 1 year after surgery. Spinal Instability Neoplastic Score, Frankel grades and complications were recorded and evaluated. RESULTS: Five patients were excluded from the analysis, and our study cohort consisted of 55 adult patients who met the inclusion criteria. The VAS and SF-36 scores of these two groups of patients significantly improved, when compared with those before the surgery (P < 0.05). There were significant differences in total cost (8835 ± 1468 vs 9540 ± 053 USD) and cement volume (4.51 ± 0.96 ml vs 6.35 ± 1.09 ml) between two groups (P < 0.05). The MVH and PVH of these two groups of patients significantly improved, when compared with those before the surgery (P < 0.05). The MVH was significantly larger in the KP group than in the VP group postoperatively (20.15 ± 4.86 vs 17.70 ± 3.78, P < 0.05) and at the final follow-up (20.42 ± 5.59 vs 17.28 ± 3.23, P < 0.05). However, the PVH of the two groups did not significantly differ at the two postoperative follow-ups (P > 0.05). No significant differences were found in surgery time, time from surgery to discharge, blood loss and complications between both groups postoperatively (P > 0.05). CONCLUSION: In the short term, both approaches are effective and safe in patients with MESCC and posterior wall destruction. The posterior internal fixation with open VP may be a good choice of surgical method in patients with MESCC and posterior wall defects.

Identification of osteoporosis based on gene biomarkers using support vector machine.

Osteoporosis is a major health concern worldwide. The present study aimed to identify effective biomarkers for osteoporosis detection. In osteoporosis, 559 differentially expressed genes (DEGs) were enriched in PI3K-Akt signaling pathway and Foxo signaling pathway. Weighted gene co-expression network analysis showed that green, pink, and tan modules were clinically significant modules, and that six genes (VEGFA, DDX5, SOD2, HNRNPD, EIF5B, and HSP90B1) were identified as "real" hub genes in the protein-protein interaction network, co-expression network, and 559 DEGs. The sensitivity and specificity of the support vector machine (SVM) for identifying patients with osteoporosis was 100%, with an area under curve of 1 in both training and validation datasets. Our results indicated that the current system using the SVM method could identify patients with osteoporosis.

Proteomic comparison between physiological degeneration and needle puncture model of disc generation disease.

BACKGROUND: The completeness of the intervertebral disc proteome is fundamental to the integrity and functionality of the intervertebral disc. METHODS: The 20 experimental rats were placed into two groups randomly, normal group (NG) and acupuncture pathological degeneration group-2 weeks (APDG-2w). The ten 24-month-old rats were grouped into physiological degeneration group (PDG). Magnetic resonance imaging, X-ray examination, histological staining (hematoxylin & eosin, safranin-O cartilage, and alcian blue staining), and immunohistochemical examination were carried out for assessing the degree of disc degradation. Intervertebral disc was collected, and protein composition was determined by LC- MS, followed by bioinformatic analysis including significance analysis, subcellular localization prediction, protein domain prediction, GO function and KEGG pathway analysis, and protein interaction network construction. LC-PRM was done for protein quantification. RESULTS: Physiological degeneration and especially needle puncture decreased T2 signal intensity and intervertebral disc height. Results from hematoxylin & eosin, safranin-O, and alcian blue staining revealed that the annulus fibrosus apparently showed the wavy and collapsed fibrocartilage lamellas in APDG-2w and PDG groups. The contents of the nucleus pulposus were decreased in physiological degeneration group and APDG-2w group compared with NG. Results from immunohistochemical analysis suggested the degeneration of intervertebral disc and inflammation in APDG-2w and PDG groups. The protein composition and expression between needle puncture rat models and the physiological degeneration group showed significant difference. CONCLUSIONS: Our studies produced point-reference datasets of normal rats, physiological degeneration rats, and needle puncture rat models, which is beneficial to subsequent pathological studies. There is differential expression of protein expression in degenerative discs with aging and acupuncture, which may be used as a potential discriminating index for different intervertebral degenerations.

Comparing the Bridge-Type Zero-Profile Anchored Spacer (ROI-C) Interbody Fusion Cage System and Anterior Cervical Discectomy and Fusion (ACDF) with Plating and Cage System in Cervical Spondylotic Myelopathy.

OBJECTIVE: To compare the clinical efficacy and radioactivity of the bridge-type zero-profile anchored spacer (ROI-C) interbody fusion cage and anterior cervical discectomy and fusion with plating and cage system (ACDF) for cervical spondylotic myelopathy (CSM). METHODS: This is a retrospective contrastive study. We recruited 35 patients who received ROI-C (ROI-C group) and 34 patients who received ACDF (ACDF group), between January 2014 to January 2019, at our treatment center. The ROI-C group comprised of 11 males and 24 females with a mean age of 61.59 ± 8.21 years (range, 51-71 years). The ACDF group comprised of 12 males and 22 females with a mean age of 60.15 ± 7.52 years (range, 52-74 years). Neck Disability Index (NDI), Japanese Orthopaedic Association score (JOA), Odom's score, cervical Cobb angle, fusion rate, adjoining ossification, and dysphagia. RESULTS: A total of 69 patients met the inclusion criteria, and these patients received more than two years of follow-up. There were significant differences in surgical duration (101 ± 22 min vs. 118 ± 29 min) and blood loss (102 ± 46 ml vs. 145 ± 58 ml) between two groups (P < 0.05). The JOA and NDI of these two groups of patients significantly improved, when compared with those before the operation (P < 0.05). Twenty-nine of 35 patients in the ROI-C group and 27 of 34 patients in ACDF group achieved good or excellent outcomes according to Odom's criteria. The cervical lordosis of both two groups significantly increased, when compared with those before the operation (P < 0.05). In the ROI-C group, the postoperative fusion rate was 85.7% at the 3-month follow-up and 100% at the final follow-up. In the ACDF group, the postoperative fusion rate was 82.4% at the 3-month follow-up and 100% at the final follow-up. The dysphagia incidence of the ACDF group was higher than that of the ROI-C group postoperatively and at the one month after surgery (P < 0.05), but no significant difference was found in the incidence of dysphagia at final follow-up (P > 0.05). CONCLUSION: Both ROI-C and ACDF achieved good therapeutic effects. However, ROI-C can reduce the operation time and postoperative complications.

Similarity and difference between aging and puncture-induced intervertebral disc degeneration.

The purpose of our study was to investigate the changes in micromorphology and mechanical properties of intervertebral discs degeneration induced by aging and puncture. Normal group (NG), 2 weeks post-puncture degeneration group (PDG) and aging degeneration group (ADG) each included 10 rats. Plain film, magnetic resonance imaging, and histological testing were utilized to assess intervertebral disc degeneration. Atomic force microscope was utilized to analyze the microstructure and elastic modulus of the intervertebral disc, while immunohistochemistry was employed to assess alterations in the cell matrix using collagen I, collagen II, matrix metalloproteinase-3 (MMP-3), and tumour necrosis factor-α (TNF-α). The results showed that the disc height ratio between PDG and ADG decreased. In the PDG and ADG group, histological scores both increased, the gray value of the T2 signal decreased, the proportion of MMP-3 and TNF-positive cells in intervertebral disc tissues was higher (p < 0.05) and the IOD values of COL-2 lower in intervertebral disc tissues (p < 0.05). The elastic modulus of PDG and ADG annulus fibers (AF) increased compared to the NG (p < 0.05); when compared to PDG, the elastic modulus of ADG AF decreased (p < 0.05). The elastic modulus of PDG and ADG collagen increased in the nucleus pulposus (NP, p < 0.05); ADG had a greater AF diameter than NG and PDG (p < 0.05). The results indicated that ADG fiber diameter thickens, and chronic inflammation indicators rise; PDG suffers from severe extracellular matrix loss. The degeneration of the ADG and PDG intervertebral discs is different. The results provide foundation for clinical research.

Does the Relationship Between Bone Cement and the Intravertebral Cleft of Kummell Disease Affect the Efficacy of PKP?

OBJECTIVE: To study the relationship between distribution of bone cement and intravertebral cleft of patients with Kummell disease on the clinical effect of percutaneous kyphoplasty (PKP). METHODS: According to the relationship between the distribution of bone cement and the cleft in the vertebrae, a total of 92 patients with Kummell disease who underwent PKP in our hospital were divided into 2 groups. Specifically, the bone cement of patients in group A was localized in the cleft of the vertebrae and did not infiltrate around the cleft, while that of group B patients not only filled the cleft of the vertebrae, but also distributed diffusely around the cleft of the vertebrae. The amount of bone cement injected, leakage rate, visual analogue scale (VAS) score, Oswestry Disability Index (ODI), and vertebral imaging changes before operation, and 2 days and 1 year after operation were compared between the 2 groups. RESULTS: The amount of bone cement injected and the permeability of bone cement in group B were higher than those in group A (P < 0.05). The scores of VAS and ODI in both groups were significantly improved after operation, but the two scores in group B were better than those in group A one year after operation. The height of anterior vertebral body and Cobb's angle of kyphosis in the 2 groups were significantly improved after operation, but 1 year after operation, those in group B were better than those in group A. CONCLUSIONS: PKP was an effective method for treating Kummell disease. At the same time, the relationship between the distribution of bone cement and the cleft in the vertebral body was an important factor affecting the curative effect after PKP. The effect of the distribution pattern of bone cement filled with intravertebral cleft and diffusely distributed around the fissures was better than that of bone cement confined in the vertebral cleft.

Long Non-Coding RNA MDFIC-7 Promotes Chordoma Progression Through Modulating the miR-525-5p/ARF6 Axis.

BACKGROUND: Chordoma, an extremely rare malignant tumor, remains difficult to be cured because of its strong local invasiveness and high recurrence rate. Long non-coding RNAs (lncRNAs) have been demonstrated to play multiple roles in various cancers. The purpose of this study was to investigate the modulatory function of lncRNA MDFIC-7 in chordoma and to elucidate its underlying mechanisms. METHODS: Quantitative real-time polymerase chain reaction was performed to detect the expression of lncRNA MDFIC-7 in tumor tissues and adjacent nontumorous tissues collected from 15 chordoma patients, as well as in chordoma cell lines. Gene silencing and overexpression experiments were carried out by RNA interference and lentiviral transduction. The effect of lncRNA MDFIC-7 on the proliferation of chordoma cells was evaluated by cell counting kit-8 assay, colony formation assay and xenograft tumor experiments. RNA immunoprecipitation and dual luciferase reporter assays were conducted to evaluate the binding between lncRNA MDFIC-7 and miRNA-525-5p and the interaction between miR-525-5p and the 3' untranslated region of ADP-ribosylation factor 6 (ARF6) mRNA. The glycolytic capacity and mitochondrial function of chordoma cells were measured by the Seahorse Bioscience XF96 Extracellular Flux Analyzer. RESULTS: The expression of lncRNA MDFIC-7 was higher in chordoma tumor tissues than in adjacent non-tumor tissues. Downregulation of lncRNA MDFIC-7 reduced colony formation and cell proliferation in chordoma cells and decreased xenograft tumor growth in a nude mouse model. Moreover, lncRNA MDFIC-7 knockdown attenuated the Warburg effect in chordoma cells and xenograft tumors. LncRNA MDFIC-7 knockdown elevated miR-525-5p levels and decreased ARF6 expressions. Overexpression of ARF6 reversed the inhibitory effect of lncRNA MDFIC-7 knockdown on cell proliferation and the Warburg effect in chordoma cells and xenograft tumors. Mechanistically, lncRNA MDFIC-7, as a molecular sponge of miR-525-5p, negatively regulated miR-525-5p expression and promoted the gene expression of ARF6, a miR-525-5p target. CONCLUSION: Our findings demonstrate that lncRNA MDFIC-7 acts as a molecular sponge to competitively bind to miR-525-5p and promote expression of ARF6. The lncRNA MDFIC-7/miR-525-5p/ARF6 axis regulates chordoma progression and the Warburg effect in chordoma, suggesting that lncRNA MDFIC-7 and miR-525-5p could be promising therapeutic targets for the treatment of chordoma.

Comparison of Clinical Outcomes Following Anterior Cervical Discectomy and Fusion with Zero-Profile Anchored Spacer-ROI-C-Fixation and Combined Intervertebral Cage and Anterior Cervical Discectomy and Fusion: A Retrospective Study from a Single Center.

BACKGROUND The aim of this study was to compare the outcomes following anterior cervical discectomy and fusion with zero-profile anchored spacer-ROI-C-fixation (ROI-C) vs combined intervertebral cage and anterior cervical discectomy and fusion (ACDF). MATERIAL AND METHODS We retrospectively analyzed 87 patients who underwent operations between January 2015 and January 2019, including 42 patients that underwent ROI-C treatment (group A) and 45 that were treated by the ACDF approach (group B). Operative duration, blood loss, dysphagia, Neck Disability Index scores (NDI), Japanese Orthopaedic Association scores (JOA), and other complications were compared between these groups. In addition, implant settlement, fusion, and cervical Cobb angle were assessed via imaging analyses. RESULTS Patients in group A and group B were followed for 22.6±3.3 months and 27.1±3.5 months, respectively (range: 13-30 months). Relative to preoperative values, JOA scores were increased and NDI scores were reduced in both groups following treatment (P<0.05), with comparable outcomes between groups (P>0.05). However, operative duration, intraoperative blood loss, and postoperative complications did differ significantly between these groups (P<0.05). Specifically, rates of short-term dysphagia were lower and recovery time was faster in group A relative to group B (P<0.05). CONCLUSIONS The findings from this study showed that ROI-C fixation achieved satisfactory outcomes, improved cervical curvature, restored intervertebral height, and was associated with shorter operative duration, reduced blood loss, and less dysphagia.

LncRNA-NONHSAT024778 promote the proliferation and invasion of chordoma cell by regulating miR-1290/Robo1 axis.

Chordoma is a malignant bone tumor originating from the embryonic remnants of the notochord. lncRNAs act as competing endogenous RNAs (ceRNAs) and play a critical role in tumor pathology. However, the biological role of lncRNA-NONHSAT024778 and the underlying molecular mechanism in chordoma remains unknown. qRT-PCR was used to analyze the expression changes of NONHSAT024778 and miR-1290 in chordoma tissues and cell lines. Bioinformatics analysis and luciferase reporter assay were applied to detect the targeting binding effect between NONHSAT024778 and miR-1290, and between Robo1 and miR-1290. The effect of NONHSAT024778 on chordoma cell proliferation and invasion and its regulation of miR-1290 by acting as a ceRNA were also investigated. An increased NONHSAT024778 expression was correlated with a decreased miR-1290 level in chordoma tissues. NONHSAT024778 knockdown suppressed the proliferation and invasion of chordoma cells. miR-1290 restored expression rescued the carcinogenic function of NONHSAT024778. Bioinformatics analysis showed that NONHSAT024778 acted as ceRNA to regulate Robo1 via sponging miR-1290 in chordoma cells, thereby promoting chordoma cell malignant progression. In vivo results confirmed the anti-tumor effects of NONHSAT024778 knockdown activating miR-1290 to inhibit the oncogene Robo1. NONHSAT024778 is substantially overexpressed, whereas miR-1290 is decreased in chordoma tissue. NONHSAT024778-miR-1290-Robo1 axis plays a critical role in chordoma tumorigenesis and might be a potential predictive biomarker for the diagnosis and therapeutic target among patients with chordoma.

Clinical efficacy and safety of bone cement combined with radiofrequency ablation in the treatment of spinal metastases.

BACKGROUND: To investigate the clinical efficacy and safety of bone cement combined with radiofrequency ablation (RFA) in the treatment of spinal metastases. METHODS: The medical records of patients with spinal metastatic tumor admitted to our hospital from January 2016 to December 2018 were retrospectively analyzed. Based on different surgical methods, the patients were divided into groups A (treated with RFA combined with bone cement) and B (treated with bone cement only). Group A included 35 patients with 47 segments of diseased vertebral bodies. Group B consisted of 52 patients with 78 vertebral segments. Pain, quality of life score, vertebra height, bone cement leakage, postoperative tumor recurrence, and complications were assessed 3 days and 1 and 6 months after surgery. RESULTS: All the patients had smooth operation without paraplegia, spinal cord injury, and perioperative death. Visual analogue scales (VAS) and Oswestry Disability Index (ODI) scores of the two groups significantly improved 3 days and 1 month after surgery compared with those before surgery (P < 0.05), but no significant difference was observed between the two groups (P > 0.05). Six months after surgery, the VAS and ODI scores of patients in group A were lower than those in group B, with statistically significant differences (P < 0.05). The postoperative vertebral body height of the two groups significantly increased compared with that before surgery, and the difference was statistically significant (P < 0.05). Meanwhile, no significant difference was observed between the two groups (P > 0.05). Postoperative bone cement permeability in group A was 6.4%, and postoperative tumor recurrence rate was 11.4%. The permeability of bone cement in group B was 20.5%, and the tumor recurrence rate was 30.8%. The bone cement permeability and tumor recurrence rate in group A were lower than those in group B, with statistically significant differences (P < 0.05). CONCLUSIONS: Bone cement combined with RFA for the treatment of spinal metastases can achieve good efficacy, desirable analgesic effect, low incidence of complications, small surgical trauma, and high safety. The proposed method has the value of clinical popularization and application.

Occipitocervical Fusion via Cervical Pedicle Fixation Assisted with O-arm Navigation.

OBJECTIVE: To describe the clinical outcomes of occipitocervical fusion (OCF) using cervical pedicle fixation with assistance of O-arm navigation and present its clinical feasibility. METHODS: From January 2015 to December 2016, eight patients with a variety of diagnoses were surgically treated with occipitocervical fusion using cervical pedicle screws under O-arm navigation. All patients received full workup consisting of clinical and radiological assessments. Perioperative parameters including operating time, intraoperative blood loss, postoperative complications, surgical outcomes were recorded. Postoperative data were acquired resorting to the scheduled follow-up 3, 6 and 12 months after their discharge and annually afterwards. The Japanese Orthopaedic Association (JOA) Scores and American Spinal Injury Association (ASIA) Scale were used to evaluate neurological function. The accuracy of screw placement was classified according to a modified classification of Gertzbein and Robbins. The fusion status was evaluated in reference to the Bridwell's posterior fusion grades. RESULTS: The patient cohort comprised of five males and three females, with the average age of 51.9 years (range from 18 to 74 years). The patients all showed indications for OCF and were performed with polyaxial screws through cervical pedicles. The average operation time was 274 min (range from 226 to 380 min), with the intraoperative blood loss of 437.5 mL and the blood transfusion volume of 481.3 mL. The average follow-up time was 23.5 months (range from 17 to 32 months). All patients exhibited radiographic evidence of osseous fusion by X-ray and computed tomography (CT) at the final follow-up. No neurovascular complications were found during the follow-up time, and the clinical symptoms were observed to be significantly improved in all the patients. Thirty-four cervical pedicle screws were implanted within the eight patients, with the accuracy of cervical pedicle screw placements as 94.1% (32/34), among which, two pedicle screws were found to broken through the cervical pedicles that were evaluated as Grade II. CONCLUSIONS: Occipitocervical fusion via cervical pedicle fixation assisted with O-arm navigation is a feasible and safe procedure with a vast range of indications.

Minimally Invasive Pedicle Screw Fixation Combined with Percutaneous Kyphoplasty Under O-Arm Navigation for the Treatment of Metastatic Spinal Tumors with Posterior Wall Destruction.

OBJECTIVE: To evaluate the safety and efficacy of O-arm-guided minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for metastatic spinal tumors with posterior wall destruction. METHODS: Patients who underwent minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for pathological vertebral fractures with posterior wall defects from January 2015 to December 2017 were followed up for 1 year. Visual analogue scale (VAS), SF-36 scores, middle vertebral height, posterior vertebral height, and the accuracy of pedicle screws were assessed preoperatively, postoperatively, and 1 year after surgery. The operation time, time from operation to discharge, blood loss, volume of bone cement, and leakage of bone cement were recorded. RESULTS: Twenty-three patients (13 females and 10 males) who met our criteria were followed up for 1 year. The operation time of these patients was 162.61 ± 33.47 min, the amount of bleeding was 230.87 ± 93.76 mL, the time from operation to discharge was 4.35 ± 2.42 days, and the volume of bone cement was 3.67 ± 0.63 mL. The VAS score decreased from 7.04 ± 1.07 to 2.65 ± 0.93 before surgery (P = 0.000) and remained at 2.57 ± 0.79 1 year after surgery. Compared with the preoperative SF-36 scores for physical pain, physiological function, energy, and social function, the postoperative scores were significantly improved (P = 0.000). The height of the middle vertebral body increased from 14.47 ± 2.96 mm before surgery to 20.18 ± 2.94 mm (P = 0.000), and remained at 20.44 to 3.01 mm 1 year after surgery. The height of the posterior vertebral body increased from 16.56 ± 3.07 mm before operation to 22.79 ± 4.00 mm (P = 0.000), and 22.45 ± 3.88 mm 1 year after surgery. The 23 patients had a total of 92 pedicle screws; 85 screws were Grade A and 7 screws were Grade B. There was no leakage of bone cement after surgery. CONCLUSION: In the short term, O-arm-guided minimally invasive pedicle screw fixation combined with kyphoplasty is safe and effective in the treatment of metastatic spinal tumors with posterior wall destruction.

Kyphoplasty in the treatment of occult and non-occult metastatic vertebral tumors.

To compare the efficacy and safety of kyphoplasty (KP) in the treatment of occult metastatic vertebral tumors (OMVT) and non-occult metastatic vertebral tumors (MVT).From January 2013 to December 2017, 65 cases of occult metastatic vertebral tumors and 82 cases of metastatic vertebral tumors were selected and divided into 2 groups. After KP, they were followed up by a year of outpatient visits and telephone calls. The visual analogue scale (VAS) and Oswestry disability index (ODI) scores, the amount of bone cement injected, the change of vertebral height and the incidence of complications were recorded, compared and analyzed by SPSS software. t test was used to compare the differences between the same group of patients at different times and between the 2 groups of patients.In the OMVT group, the operation time was 24.52 ±â€Š4.24 minutes, the fluoroscopy time was 10.18 ±â€Š1.53 minutes and the volume of bone cement was 3.62 ±â€Š0.93 ml. The VAS score decreased from 7.26 ±â€Š01.08 preoperatively to 2.77 ±â€Š0.93 postoperatively (P < .01). The ODI score decreased from 64.89 ±â€Š9.05 preoperatively to 25.82 ±â€Š4.63 postoperatively (P < .01). In the MVT group, the operation time was 26.63 ±â€Š4.61 minutes, the fluoroscopy time was 11.04 ±â€Š2.15 minutes and the volume of bone cement was 4.09 ±â€Š1.10 ml. The VAS score decreased from 7.73 ±â€Š0.94 preoperatively to 3.22 ±â€Š0.80 postoperatively (P < .01). The ODI score decreased from 69.20 ±â€Š7.14 preoperatively to 28.02 ±â€Š4.40 postoperatively (P < .01). The vertebral height of MVT patients was significantly improved after operation (P < .01), but there was no difference in OMVT patients (P > .05).Occult metastatic vertebral tumors can be detected by Magnetic Resonance Imaging (MRI), and KP may be more effective and safer in the treatment of OMVT.

Cystine dimethyl ester cross-linked PEG-poly(urethane-urea)/nano-hydroxyapatite composited biomimetic scaffold for bone defect repair.

Polyurethane (PU) and polyurea (PUA) materials have shown significant potential for application in tissue repair. Herein, we design a glycerol ethoxylate (PEG)-based poly(urethane-urea) for bone tissue repair. The polymer precursor was prepared from the reaction of PEG and isophorone diisocyanate (IPDI). The cystine dimethyl ester was used as a cross-linker for the preparation of poly(urethane-urea) elastomers. The material was further strengthened by physical blending of nano-hydroxyapatite (nHA). The physical and biological properties of final material were evaluated by mechanical testing, scanning electron microscopy characterization, degradation tests, cell proliferation and cell differentiation assays. The obtained scaffolds showed good mechanical strength, excellent biocompatibility and osteogenic capability. All the evidences demonstrated that this type of materials has good prospects for bone tissue repair application.

Kyphoplasty for occult and non-occult osteoporotic vertebral fractures: a retrospective study.

OBJECTIVE: To compare the safety and efficacy of kyphoplasty in the treatment of occult and non-occult osteoporotic vertebral compression fractures (OOVF). MATERIAL AND METHODS: From 2015 to 2017, 82 OOVF and 105 non-occult osteoporotic vertebral compression fractures (N-OOVF) were evaluated with the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and vertebral height preoperatively, immediately postoperatively, and one year postoperatively. Operative time, fluoroscopy time, and cement injection volume were recorded. RESULTS: Compared with the preoperative VAS and ODI scores, the scores of both groups were significantly improved after surgery. Preoperative ODI and VAS scores of the OOVF were lower than those of the N-OOVF. The operative time, fluoroscopy time, and bone cement injection volume of the OOVF were significantly lower than those of the N-OOVF. Vertebral height of the N-OOVF improved significantly after surgery. There were differences in cement leakage and adjacent vertebral fractures between the two groups. CONCLUSION: Compared with N-OOVF, OOVF are safer with kyphoplasty, and it is necessary to diagnose OOVF in a timely manner.

A distraction technique using reduction multi-axial screws for open reduction of high-grade lumbar posterior dislocation:a case report and literature review.

BACKGROUND: L3 vertebral fractures with posterior dislocation are rare and usually secondary to high-energy trauma. To assess the outcome of a valuable distraction technique, using long-tail multiaxial pedicle screw which we have employed in reduction of L3 vertebral fracture with posterior dislocation, and emphasize the importance of preoperative blood vessel evaluation. CASE PRESENTATION: A 47-year-old patient fell from a height of 4 m and was paralyzed. Computed tomography scan revealed a three-column ligamentous injury with posterior fracture-dislocation of the L3 vertebral body. Computed tomography angiography showed that the third lumbar artery was ruptured without active bleeding. The patient underwent posterior approach with reduction, transpedicular fixation, and posterolateral fusion with autologous bone graft. Finally, Vertebral reduction and sagittal balance were achieved and patients recovered well after operation. CONCLUSION: Preoperative blood vessel evaluation is very important to avoid massive bleeding during the surgery, and the standard technique which can achieve good reduction is easy to understand, perform, and is reproducible.