For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To assess the cytotoxicity of self-adhesive resin cement RelyXTM U200 on human periodontal ligament fibro-blasts(HPDLFs)under different light treatment modes.Methods:The self-adhesive resin cement RelyXTM U200 was cured by immediate light(A),intermittent light(B),delayed light(C)and no light(D)treatment respectively.The HPDLFs were cultured with the specimen extracts under different light modes.The proliferation ability and apoptosis level of the cells in the groups were detected by CCK-8 test and flow cytometry apoptosis test.SPSS 20.0 software was used to analyze the cytotoxicity of specimens to HPDLFs.Results:At 24 h after light treatment the cytoxicity(grade)of group A,B,C and D was 1,2,3 and 4,at 72 h 1,2,2 and 3,respectively.At 72 h,the apoptosis index(％)of the cells in A,B,C and D groups was 6.38％±0.94％,16.34％±1.67％,24.13％±1.43％and 38.34％±2.75％respecitvely.Conclusion:The cytotoxicity of self-adhesive resin cement is the greatest under no light treatment mode and the least under immediate light treatment mode.

The clinical demand for bone graft materials is substantial, but materials other than autologous bone generally suffer from insufficient osteogenic activity. Bone marrow concentration-based bone repair technology addresses this by concentrating stem cells and cytokines from autologous bone marrow onto scaffold materials (such as allograft bone, demineralized bone matrix, tricalcium phosphate, hydroxyapatite, etc.) to construct highly active bone repair materials, effectively enhancing their osteogenic efficacy. Current evidence suggests that this technology can be used in the surgical treatment of bone ununion, bone defects, benign bone tumors and tumor-like lesions, femoral head necrosis, and spinal fusion. The core steps of this technology include bone marrow aspiration, bone marrow concentration, and bone grafting. Among these, bone marrow aspiration and bone grafting are routine clinical techniques, while bone marrow concentration can be accomplished using specialized devices. Based on reasonable indication selection and strict operating procedures, bone marrow-enriched biomaterials can be rapidly prepared and implanted intraoperatively. This technology has already established a foundation for application both domestically and internationally and has effectively addressed the key clinical issue of inadequate activity in conventional bone graft materials, demonstrating significant application prospects.

Objective:To assess the cytotoxicity of self-adhesive resin cement RelyXTM U200 on human periodontal ligament fibro-blasts(HPDLFs)under different light treatment modes.Methods:The self-adhesive resin cement RelyXTM U200 was cured by immediate light(A),intermittent light(B),delayed light(C)and no light(D)treatment respectively.The HPDLFs were cultured with the specimen extracts under different light modes.The proliferation ability and apoptosis level of the cells in the groups were detected by CCK-8 test and flow cytometry apoptosis test.SPSS 20.0 software was used to analyze the cytotoxicity of specimens to HPDLFs.Results:At 24 h after light treatment the cytoxicity(grade)of group A,B,C and D was 1,2,3 and 4,at 72 h 1,2,2 and 3,respectively.At 72 h,the apoptosis index(％)of the cells in A,B,C and D groups was 6.38％±0.94％,16.34％±1.67％,24.13％±1.43％and 38.34％±2.75％respecitvely.Conclusion:The cytotoxicity of self-adhesive resin cement is the greatest under no light treatment mode and the least under immediate light treatment mode.

The clinical demand for bone graft materials is substantial, but materials other than autologous bone generally suffer from insufficient osteogenic activity. Bone marrow concentration-based bone repair technology addresses this by concentrating stem cells and cytokines from autologous bone marrow onto scaffold materials (such as allograft bone, demineralized bone matrix, tricalcium phosphate, hydroxyapatite, etc.) to construct highly active bone repair materials, effectively enhancing their osteogenic efficacy. Current evidence suggests that this technology can be used in the surgical treatment of bone ununion, bone defects, benign bone tumors and tumor-like lesions, femoral head necrosis, and spinal fusion. The core steps of this technology include bone marrow aspiration, bone marrow concentration, and bone grafting. Among these, bone marrow aspiration and bone grafting are routine clinical techniques, while bone marrow concentration can be accomplished using specialized devices. Based on reasonable indication selection and strict operating procedures, bone marrow-enriched biomaterials can be rapidly prepared and implanted intraoperatively. This technology has already established a foundation for application both domestically and internationally and has effectively addressed the key clinical issue of inadequate activity in conventional bone graft materials, demonstrating significant application prospects.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Bone defects caused by different causes such as trauma, severe bone infection and other factors are common in clinic and difficult to treat. Usually, bone substitutes are required for repair. Current bone grafting materials used clinically include autologous bones, allogeneic bones, xenografts, and synthetic materials, etc. Other than autologous bones, the major hurdles of rest bone grafts have various degrees of poor biological activity and lack of active ingredients to provide osteogenic impetus. Bone marrow contains various components such as stem cells and bioactive factors, which are contributive to osteogenesis. In response, the technique of bone marrow enrichment, based on the efficient utilization of components within bone marrow, has been risen, aiming to extract osteogenic cells and factors from bone marrow of patients and incorporate them into 3D scaffolds for fabricating bone grafts with high osteoinductivity. However, the scientific guidance and application specification are lacked with regard to the clinical scope, approach, safety and effectiveness. In this context, under the organization of Chinese Orthopedic Association, the Expert consensus for the clinical application of autologous bone marrow enrichment technique for bone repair ( version 2023) is formulated based on the evidence-based medicine. The consensus covers the topics of the characteristics, range of application, safety and application notes of the technique of autologous bone marrow enrichment and proposes corresponding recommendations, hoping to provide better guidance for clinical practice of the technique.

Infectious bone defect is bone defect with infection or as a result of treatment of bone infection. It requires surgical intervention, and the treatment processes are complex and long, which include bone infection control,bone defect repair and even complex soft tissue reconstructions in some cases. Failure to achieve the goals in any step may lead to the failure of the overall treatment. Therefore, infectious bone defect has been a worldwide challenge in the field of orthopedics. Conventionally, sequestrectomy, bone grafting, bone transport, and systemic/local antibiotic treatment are standard therapies. Radical debridement remains one of the cornerstones for the management of bone infection. However, the scale of debridement and the timing and method of bone defect reconstruction remain controversial. With the clinical application of induced membrane technique, effective infection control and rapid bone reconstruction have been achieved in the management of infectious bone defect. The induced membrane technique has attracted more interests and attention, but the lack of understanding the basic principles of infection control and technical details may hamper the clinical outcomes of induced membrane technique and complications can possibly occur. Therefore, the Chinese Orthopedic Association organized domestic orthopedic experts to formulate An evidence-based clinical guideline for the treatment of infectious bone defect with induced membrane technique ( version 2023) according to the evidence-based method and put forward recommendations on infectious bone defect from the aspects of precise diagnosis, preoperative evaluation, operation procedure, postoperative management and rehabilitation, so as to provide useful references for the treatment of infectious bone defect with induced membrane technique.

Objective:To investigate the effect and mechanism of circular RNA (cirRNA) on the radiosensitivity of rectal cancer.Methods:The differential circRNAs in radiosensitive and radioresistant rectal cancer tissues (biopsy tissue before radiotherapy and chemotherapy) were detected by gene sequencing, and the effect of circRNAs on the radiosensitivity of colorectal cancer cells was further confirmed in vitro. Results:Through gene sequencing of rectal cancer tissue samples, 64 circRNAs were found to be highly expressed in radiosensitive rectal cancer tissues, and 36 circRNAs were lowly expressed in radiosensitive tissues. Ten differential circRNAs were selected and verified by qRT-PCR, and it was found that circATL2 was highly expressed in radiosensitive rectal cancer tissues. In vitro cell experiment indicated that up-regulation of circATL2 expression could significantly improve the radiosensitivity of rectal cancer. Subsequently, 8 miRNAs lowly expressed in radiosensitive rectal cancer tissues were analyzed. The direct binding relationship between miR-205 and circATL2 was confirmed by dual luciferase reporter assay. The rescue experiment confirmed that circATL2 in rectal cancer regulated the radiosensitivity of rectal cancer through miR-205. Conclusion:circATL2 regulates the radiosensitivity of rectal cancer by binding to miR-205.

Objective To investigate the mechanism of implanted tissue-engineered bone (TEB)recruiting endogenous mesenchymal stem cells (BMSCs) towards bone regeneration after traumatic bone defect.Methods In vivo experiments:2 mm of diaphysis and periosteum were removed from the middle of the femoral shaft in 8 week old FVB/N mice to form a large segment of bone defect.Demineralized bone matrix (DBM) and TEB were implanted into the defect area and fixated.All mice were randomly divided into DBM group (n =18) and TEB group (n =18).The results were observed 24 hours after implantation:(1) flow cytometry was used to evaluate the number of mobilized host BMSCs into the blood;(2) non-invasive bioluminescent imaging was used to observe the ability of two groups in recruiting mouse bone marrow derived mesenchymal stem cells (mBMSCs) in peripheral blood to the defect area;(3) ELISA was used to evaluate the stromal cell-derived factor 1 (SDF-1) content in peripheral blood of two groups.In vitro experiments:(1) transwell assay was conducted to evaluate the ability of SDF-1 (100 ng/ml) in promoting the migration of human bone marrow derived mesenchymal stem cells (hBMSCs).SDF-1/C-X-C motif chemokine receptor-4 (CXCR4) pathway was blocked by the selective CXCR4 antagonist Plerixafor (AMD3100).The experimental groups were divided into control group,SDF-1 group,and SDF-1 + AMD3100 group.(2) The co-culture system of human umbilical vein endothelial cells (hUVECs) and hBMSCs was established,and cells were stimulated by SDF-1.The experimental groups were divided into hBMSCs group,hBMSCs + hUVECs group,and hBMSCs + hUVECs (AMD3100 pretreatment) group.Transwell assays were used to compare the migration of hBMSCs in each group.ELISA was used to detect the concentration of hepatocyte growth factor (HGF) in the co-culture supernatant.(3) In vitro cultured hUVECs were stimulated by SDF-1 and SDF-1/CXCR4 pathway was antagonized by AMD3100.The experimental groups were divided into control group,SDF-1 group,and SDF-1 + AMD3100 group.Quantitative real-time polymerase chain reaction (qRT PCR) was used to evaluate the expression of HGF in each group.Results In vivo experiments:24 h after transplantation,the number of BMSCs and SDF-1 concentration in the TEB group were significantly highcr than those in the DBM group (P ＜ 0.05).The number of recruited mBMSCs into the circulation in the TEB group was larger than that in the DBM group (P＜ 0.01).In vitro experiments:(1) compared with the control group and the SDF-1 + AMD3100 group,the SDF-1 group significantly enhanced the migration ability of hBMSCs in Transwell migration experiments (P ＜ 0.01);(2) compared with the hBMSCs group and the hBMSCs + hUVECs (AMD3100 pretreatment) group,the number of migrated cells and HGF concentration in the hBMSCs + hUVEC group significantly increased (P ＜ 0.01),but there were no significant differences between the hBMSCs group and the hBMSCs + hUVECs (AMD3100 Pretreatment) group (P ＞0.05);(3) qRT-PCR showed that the expression of HGF was significantly increased in the SDF-1 group compared with the control group (P ＜ 0.05).After antagonizing SDF-1/CXCR4,HGF expression in the SDF-1 + AMD3100 group was significantly lower than that in the SDF-1 group.Conclusions TEB transplantation in traumatic bone defect can significantly increase the concentration of chemokine SDF-1 in vivo and effectively promote the mobilization of endogenous MSCs and recruitment of circulating MSCs.SDF-1 not only directly promotes the migration of hBMSCs through SDF-1/CXCR4 pathway,but also up-regulates the expression and secretion of HGF in vascular cells to further amplify the chemotactic effect of SDF-1 on hBMSCs.