BACKGROUND:Titanium elastic intramedullary nailing for the treatment of significantly displaced midshaft clavicle fractures has the characteristics of minimally invasive and elastic fixation.The displacement of the fracture is closely related to the later function.However,there are few studies on the three-dimensional displacement analysis of the fracture ends before surgery and after intramedullary fixation such as titanium elastic intramedullary nailing.OBJECTIVE:To explore the three-dimensional displacement of fracture ends after midshaft clavicle fracture and fixation with titanium elastic intramedullary nails,and to analyze the risk factors.METHODS:A total of 91 patients with midshaft clavicle fracture(fracture end shortening ≥15 mm)admitted to Wendeng Orthopedic Hospital of Shandong Province from April 2019 to April 2024 were selected,including 57 males and 34 females,aged(51.73±10.21)years old.All patients received closed reduction and internal fixation with titanium elastic intramedullary nail.CT scans of the affected clavicle were performed before and on the first day after surgery.The CT data were imported into Mimics software for modeling.The length of the clavicle,lateral displacement of the fracture end,and rotation of the distal end of the fracture along the X,Y,and Z axes were measured and recorded before and after surgery.Pearson correlation coefficient was used for correlation analysis of various parameters,and generalized linear regression was used to evaluate risk factors.RESULTS AND CONCLUSION:(1)Preoperatively,the variable that increased the risk of lateral displacement was the number of comminuted bone fragments,the variable that increased the risk of shortening displacement was male patients,and the variable that increased the risk of Z-axis rotation was the left limb.Shortening displacement was significantly positively correlated with lateral displacement(r=0.715,P＜0.001);shortening displacement was significantly positively correlated with X-axis rotation displacement and Y-axis rotation displacement(r=0.265,P=0.028;r=0.303,P=0.011);lateral displacement was significantly positively correlated with Y-axis rotation and Z-axis rotation(r=0.258,P=0.032;r=0.250,P=0.038);X-axis rotation was significantly positively correlated with Y-axis rotation(r=0.382,P=0.001),and Z-axis rotation was significantly positively correlated with Y-axis rotation(r=0.280,P=0.020).(2)Postoperatively:The number of scapula fractures and comminuted bone fragments were variables that increased the risk of postoperative shortening and lateral displacement:Preoperative X-,Y-,and Z-axis rotation displacements were risk variables that increased postoperative X-,Y-,and Z-axis rotation displacements,respectively.Postoperative lateral displacement was significantly positively correlated with postoperative shortening and displacement(r=0.584,P=0.000),and postoperative lateral displacement was also significantly positively correlated with postoperative Y axis rotation and Z axis rotation(r=0.360,P=0.002;r=0.250,P=0.038).Postoperative Y axis rotation was significantly positively correlated with postoperative Z axis rotation(r=0.248,P=0.040).(3)The results showed that the three-dimensional displacement of the clavicle end before and after surgery was affected by many factors,especially the number of comminuted bone fragments,scapula fractures,gender,and original rotation displacement.At the same time,there were complex correlations between various displacements,especially the correlation between shortening displacement and lateral displacement was the strongest.

BACKGROUND:Dental mesenchymal stem cells are considered a promising source for bone tissue repair due to their high proliferation potential,osteogenic differentiation capacity,and immunomodulatory properties.However,some allogeneic applications of stem cells still have potential carcinogenic effects and immune rejection risks.Recently,studies have highlighted the paracrine effects mediated by secretions from dental mesenchymal stem cells in bone tissue repair.These secretions include the soluble factors and extracellular vesicles.OBJECTIVE:To review the research progress of dental mesenchymal stem cells in repairing bone defects through paracrine effects.METHODS:Using search terms"dental mesenchymal stem cell,paracrine,osteogenesis,conditioned medium,extracellular vesicle"in Chinese and English,relevant literature published between 2019 and 2024 was retrieved from databases including CNKI,PubMed,and Elsevier ScienceDirect.A total of 104 studies were ultimately selected for this review.RESULTS AND CONCLUSION:(1)Dental mesenchymal stem cells-conditioned medium contains multiple bioactive factors beneficial for bone repair.These factors directly promote bone formation through regulatory agents such as osteocalcin,osteopontin,bone morphogenetic protein,and dentin sialophosphoprotein.They also play an indirect promoting role in bone tissue repair through neurotrophic factors,vascular endothelial growth factor,and immunomodulatory and anti-inflammatory agents.(2)Dental derived mesenchymal stem cell-derived extracellular vesicles not only contain some cytokines from dental conditioned medium,but also various miRNAs,which promote bone repair by directly promoting osteogenesis,angiogenesis,regulating immune cells,and inflammation control.These extracellular vesicles can be engineered within different scaffold materials to achieve controlled or sustained release,enhancing therapeutic efficacy.

BACKGROUND:Currently,treatment method for knee osteoarthritis includes oral medicine,joint cavity drug injection,and physiotherapy,but the curative effect is limited.Existing studies have confirmed that silicon-based bioceramics can promote cartilage and subchondral bone repair and vascular regeneration.OBJECTIVE:To explore the effect of different concentrations of silicon-based bioceramics injected into the knee joint cavity in the treatment of knee osteoarthritis in rats.METHODS:Silicon-based bioceramics-calcium silicate was prepared.Twenty-five SD rats were randomly divided into five groups,with five rats in each group.The healthy group did not receive any intervention,and the modeling group,low-dose calcium silicate group,high-dose calcium silicate group,and saline group used anterior cruciate ligament transection to establish bilateral knee osteoarthritis models.Four weeks after modeling,0.05 mL of 50 and 100 mg/mL calcium silicate solution were injected into the knee joint cavity in the low-dose calcium silicate group and high-dose calcium silicate group,respectively,and 0.05 mL of saline was injected into the knee joint cavity in the saline group,once a week for 4 consecutive weeks.In the fifth week of administration,bilateral knee joint Micro-CT detection,knee joint cartilage hematoxylin-eosin staining,and modified Mankin score were performed.RESULTS AND CONCLUSION:(1)Micro-CT quantitative analysis showed that compared with the healthy group,the volume fraction and number of trabeculae of the medial tibial plateau in the modeling group decreased(P＜0.05),and the separation of trabeculae increased(P＜0.05).Compared with the modeling group,the volume fraction and number of trabeculae of the medial tibial plateau in the low-dose calcium silicate group and the saline group increased(P＜0.05),and the separation of trabeculae decreased(P＜0.05).(2)Hematoxylin-eosin staining showed that the cartilage surface of the healthy group and the low-dose calcium silicate group was relatively smooth and flat,the chondrocytes were evenly distributed,without clustered chondrocytes,the tide line was complete,and the staining was uniform;the cartilage surface of the high-dose calcium silicate group was slightly uneven,the middle and deep cells were disordered,with a small number of clustered chondrocytes,the tide line was discontinuous,and the staining was uneven;the cartilage surface of the saline group and the modeling group was obviously rough,the cells were disordered,with a large number of clustered chondrocytes,the tide line disappeared,and the staining was uneven.The modified Mankin score of the healthy group was lower than that of the high-dose calcium silicate group,the saline group,and the modeling group(P＜0.05).The modified Mankin score of the high-dose calcium silicate group and the low-dose calcium silicate group was lower than that of the saline group and the modeling group(P＜0.05).(3)The results show that calcium silicate knee joint injection has a certain effect in the treatment of knee osteoarthritis.Compared with 100 mg/mL calcium silicate solution,50 mg/mL calcium silicate solution can promote the recovery of subchondral bone and cartilage.

BACKGROUND:Magnetic nanomaterials,as a hot topic in the biomedical field in recent years,are often used to enhance the targeted delivery of drugs to the affected area.OBJECTIVE:To investigate the effects of magnetic nano drug carriers on skeletal muscle injury markers and inflammatory responses in rats with sports injuries.METHODS:Magnetic nanoparticles were prepared.A total of 88 male SD rats were randomly divided into a blank group(n=8),an injury control group(n=32),a Yunnan Baiyao group(n=24),and a magnetic nano-drug carrier group(n=24)by using a random number table method.The latter three groups were modeled with exercise-induced muscle injury(treadmill slope of-16°,running speed of 16 m/min,and training time of 120 min).Immediately after exercise,after verifying the success of the model,Yunnan Baiyao patch was applied to the gastrocnemius muscle of the rats in the Yunnan Baiyao group.Yunnan Baiyao patch loaded with magnetic nanoparticles was applied to the gastrocnemius muscle of the rats in the magnetic nano-drug carrier group.At 24,48,and 120 hours after exercise,blood was drawn from the abdominal aorta of rats to detect the activities of creatine kinase and lactate dehydrogenase,as well as the levels of myoglobin,interleukin-6,and tumor necrosis factor-α.Hematoxylin-eosin staining was used to observe the infiltration of inflammatory cells in the gastrocnemius muscle.RESULTS AND CONCLUSION:(1)Compared with the blank group,the levels of myoglobin,creatine kinase,lactate dehydrogenase and tumor necrosis factorα in the injury control group at 24,48 and 120 hours after exercise were increased(P＜0.05),and the level of interleukin 6 at 24 and 120 hours after exercise was increased(P＜0.05).Compared with the injury control group,the level of myoglobin in the Yunnan Baiyao group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and lactate dehydrogenase at 24,48 and 120 hours were decreased(P＜0.05),and the levels of interleukin 6 and tumor necrosis factor α at 120 hours after exercise were decreased(P＜0.05).Compared with the Yunnan Baiyao group,the level of myoglobin in the magnetic nano-drug carrier group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and tumor necrosis factor α at 48 and 120 hours after exercise were decreased(P＜0.05),and the lactate dehydrogenase activity was reduced(P＜0.05).(2)Hematoxylin-eosin staining showed that a large number of inflammatory cells infiltrated in the muscle fibers of the injury control group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the local damaged muscle fibers began to regenerate 120 hours after exercise.A large number of inflammatory cells infiltrated in the muscle fibers of the Yunnan Baiyao group and the magnetic nano-drug carrier group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the damaged muscle fibers were regenerating 120 hours after exercise,and there was no significant difference from the blank group.(3)The results show that Yunnan Baiyao patch combined with magnetic nanoparticles can accelerate the recovery of exercise-induced muscle injury in rats,and the effect is better than that of Yunnan Baiyao alone.

BACKGROUND:Type 2 diabetes mellitus is a secondary causative factor for osteoporosis.As highly heterogeneous innate immune cells,macrophages may be polarized in a hyperglycemic environment,which affects osteogenesis-angiogenesis coupling.This may be a research target for improving bone quality in patients with type 2 diabetic osteoporosis.OBJECTIVE:To explore the role of modulating macrophage M1/M2 polarization to influence osteogenesis-angiogenesis coupling in type 2 diabetic osteoporosis and to summarize the effects of commonly used anti-glucose and anti-osteoporosis drugs and bone biorepair materials on bone osteogenesis-angiogenesis coupling by regulating macrophage M1/M2 polarization.METHODS:The keywords of"macrophage polarization,type 2 diabetes,osteoporosis,osteogenesis-angiogenesis coupling"in Chinese and"macrophages,macrophage polarization,osteogenesis-angiogenesis coupling"in English were used to search for relevant literature in CNKI and PubMed,respectively.Seventy-nine pieces of literature were screened and analyzed.RESULTS AND CONCLUSION:(1)Type 2 diabetes mellitus causes the body to be in a hyperglycemic environment and increases the secretion of inflammatory-related factors in the body,which promotes macrophage polarization towards M1 and decreases the number of M2 macrophages.(2)In type 2 diabetes,promoting M2 macrophage polarization is beneficial for osteogenesis-angiogenesis coupling.(3)Some anti-glycemic drugs,active ingredients in traditional Chinese medicine and bone biorepair materials can improve type 2 diabetic osteoporosis by regulating macrophage M1/M2 polarization,reducing M1/M2 ratio,and promoting osteogenesis-angiogenesis coupling.

BACKGROUND:The exact pathogenesis of temporomandibular joint osteoarthritis is currently unclear.Traditional clinical treatment strategies for temporomandibular joint osteoarthritis are symptomatic treatments such as pain relief and reduction of inflammation,which can stop the progression of the disease to a certain degree but cannot reverse the destruction of the cartilage.Cartilage degeneration,as one of the most prominent pathologic features in the development of temporomandibular joint osteoarthritis,has been the subject of an increasing number of studies that focus on its pathogenesis.Consequently,we hope to provide an ideal radical solution for the regeneration of the temporomandibular joint.OBJECTIVE:To review the progress of research on cartilage degeneration in temporomandibular joint osteoarthritis.METHODS:The search terms were"temporomandibular joint osteoarthritis,degradation of cartilage matrix,synovitis,oxidative stress,chondrocyte hypertrophy,chondrocyte apoptosis,ferroptosis,autophagy,angiogenesis,extracellular vesicles"in Chinese and English.Literature search was conducted in PubMed database and CNKI,and the time limit for the search was from January 2004 to October 2024.Screening was performed by analyzing and reading the literature,and according to the inclusion and exclusion criteria,81 papers were finally included for review.RESULTS AND CONCLUSION:(1)Increased secretion of cartilage matrix degrading enzymes causes degradation of the cartilage matrix,leading to cartilage degeneration.(2)Synovitis promotes cartilage degeneration through macrophage M1-type polarization and production of inflammatory mediators.(3)Oxidative stress promotes cartilage degeneration by exacerbating the inflammatory response through overproduction of reactive oxygen species.(4)Chondrocyte phenotypic changes and death lead to the decrease of cartilage matrix synthesis,resulting in cartilage degeneration.(5)Blood vessels of subchondral bone penetrate the calcified cartilage layer to reach the superficial cartilage layer,which destroys the cartilage structure and leads to cartilage degeneration.(6)Bioactive substances carried by serum-derived extracellular vesicles in inflammatory states also promote cartilage degeneration in temporomandibular joint osteoarthritis.

BACKGROUND:Macrophages play a key role in the occurrence and progression of lung diseases,and autophagy plays an important role in maintaining environmental homeostasis and functional stability in macrophages.It has been suggested that macrophage autophagic activity has two sides in lung inflammatory diseases.OBJECTIVE:To summarize the relationship between macrophage autophagy and lung diseases,thereby providing reference for exploring the prevention and treatment strategies of lung inflammatory diseases by targeting macrophage autophagy.METHODS:Literature retrieval was performed in CNKI and PubMed for relevant literature published from database inception to September 2024.The search terms were"macrophage autophagy,efferocytosis,macrophage polarization,acute lung injury,pneumonia,chronic obstructive pulmonary disease,pulmonary fibrosis,asthma"in Chinese and English,respectively.The search results were included or excluded based on the selection criteria,and 100 papers that met the criteria were finally included in the review.RESULTS AND CONCLUSION:(1)The obstruction of autophagy flow will induce the polarization imbalance of macrophages and impair their efferocytosis,resulting in the increase of M1 macrophages and aggravating inflammation.(2)The judgment of autophagic activity should be based on whether the autophagy flow is smooth or not,and it is essential to evaluate the degradation ability of autophagy.Some studies failed to comprehensively detect the degradation ability of autophagy lysosomes to assess whether the autophagy flow is unobtrusive.As a result,the so-called two-sided view of pulmonary macrophage autophagy in pulmonary inflammatory diseases in such studies is actually related to the one-sided judgment of autophagy activity.(3)The pathological manifestations vary across different pulmonary diseases and even at different stages of the same disease.Activation of macrophage autophagy plays a positive role in regulating pulmonary inflammatory homeostasis in conditions such as acute lung injury,infectious pneumonia,mild chronic obstructive pulmonary disease,early-stage pulmonary fibrosis,and secondary asthma.However,in the severe fibrotic stage of chronic obstructive pulmonary disease and the progressive stage of pulmonary fibrosis,the activation of pulmonary macrophage autophagy aggravates pulmonary fibrosis,reflecting the dual nature of macrophage autophagy.In allergic asthma,autophagy is activated in lung-resident macrophages but suppressed in infiltrating monocyte-derived macrophages from circulation.The former is closely related to airway stenosis,and the latter aggravates pneumonia disorders.Therefore,identifying the types and progression stages of lung diseases,along with accurately assessing autophagic activity,is crucial for future investigations into the relationship between macrophage autophagy and disease pathogenesis,thereby facilitating the development of therapeutic strategies in the future.

BACKGROUND:Previous studies of the research group have found that icariin-containing serum can delay the progression of knee osteoarthritis,promote chondrocyte proliferation and stem cell cartilage differentiation in rats,but there is still a lack of sufficient basis for clinical application.OBJECTIVE:To investigate the repair effect of icariin-containing serum on lipopolysaccharide-induced inflammatory damage of human chondrocytes.METHODS:The effect of icariin-containing serum on chondrocyte viability was detected by cell counting kit-8 method,and the optimal volume fraction and time of icariin-containing serum were screened.The cells were then divided into blank group,lipopolysaccharide group,icariin-containing serum group and lipopolysaccharide+icariin-containing serum group.After grouping,immunofluorescence was used to detect the secretion of type Ⅱ collagen in chondrocytes in each group.Real-time PCR was used to detect the expression of related genes.RESULTS AND CONCLUSION:(1)Icariin-containing serum showed good biosafety characteristics for human chondrocytes,and the cell viability reached the highest level after 48 hours of intervention when the icariin-containing serum volume fraction was 15％,and the follow-up experiments were carried out according to the conditions.(2)Compared with the blank group,lipopolysaccharide significantly inhibited the expression of type Ⅱ collagen in chondrocytes,while icariin-containing serum showed a positive mobilization effect,which could effectively promote the secretion of type Ⅱ collagen in chondrocytes under normal and inflammatory conditions.(3)The mRNA expression of type Ⅱ collagen and Aggrecan in chondrocytes decreased significantly under lipopolysaccharide stimulation,and the mRNA expression levels of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 increased significantly.Icariin-containing serum promoted the mRNA expression of type Ⅱ collagen in human chondrocytes under inflammatory conditions and reduced the mRNA expression of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 in chondrocytes after lipopolysaccharide intervention.Therefore,these findings indicate that the icariin-containing serum has good safety for human chondrocytes and plays an important role in maintaining the normal physiological functions of chondrocytes,promoting the synthesis of extracellular matrix,and inhibiting the secretion of inflammatory factors.

BACKGROUND:Plate fixation is the mainstream method for the surgical treatment of distal femoral fractures.The intramedullary nailing has the advantages of minimally invasive,such as less soft tissue injury and bone blood supply destruction.At the same time,it is a central fixation and has better biomechanical effect.Therefore,retrograde intramedullary nailing has become another option for the internal fixation of distal femoral fractures.OBJECTIVE:The biomechanical characteristics of new retrograde intramedullary nail on lateral femur condyle,common femoral retrograde intramedullary nail,and lateral femur condyle anatomical locking plate for the treatment of A2-type distal femoral fractures were compared using finite element analysis,and the advantages of new retrograde intramedullary nail on lateral femur condyle was studied.METHODS:A new retrograde intramedullary nail on lateral femur condyle was designed,which was inserted into the bone cortex in front of the insertion point of the lateral collateral ligament of the lateral femoral condyle.A CT scan was performed on the lower limb bone of a male volunteer,and a three-dimensional model of the femur was established.The model was then segmented to create a three-dimensional model of a femoral distal A2-type fracture,The three-dimensional models of small(small group),standard type retrograde intramedullary nail on the lateral femoral condyle(standard group),common retrograde intramedullary needle(common group),and lateral femur condyle anatomical locking plate(plate group)were established respectively.The axial stresses of 600,1 800 N and the torsional load of 4 000,8 000 N·mm were applied to the models,and the displacement and stress of femur and the displacement,stress and shear force of internal fixators were observed in each group.RESULTS AND CONCLUSION:(1)When subjected to axial load of 600 and 1 800 N,the femoral peak displacement,the femoral peak stress,and the peak stress of interal fixation in the standard group were the lowest among the four groups.(2)When subjected to torsional load of 4 000 and 8 000 N·mm,the femoral peak displacement and peak displacement of the internal fixation in the standard group were the lowest among the four groups.(3)Compared with femoral lateral condylar locking plate and common retrograde intramedullary needle,the new retrograde intramedullary needle on lateral femur condyle has mechanical advantages of reducing stress concentration and decreasing the risk of internal fixation failure.

BACKGROUND:In 2019,the modified cortical bone trajectory technique was proposed by our team,significantly improving traditional methods.Previous studies have highlighted its superior biomechanical properties for segment fixation.However,a comprehensive systematic analysis of its specific biomechanical effects on adjacent segment degeneration is lacking,particularly regarding its influence on range of motion and intervertebral disc stress in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion techniques.OBJECTIVE:To investigate the biomechanical effects of modified cortical bone trajectory screw techniques on adjacent segment degeneration in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion.METHODS:CT scans were performed on three human cadaver specimens to establish and validate three-dimensional intact finite element models of the L1-S1 segment.For each of these,the posterior lumbar interbody fusion or transforaminal lumbar interbody fusion with three different fixation techniques was reconstructed at the L4-L5 segment.The L4-L5 segment was fixed using three different internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws).The range of motion and von Mises stress of the intervertebral disc of the L3-L4 and L5-S1 segments were recorded with a 400 N compressive load and 7.5 N moments in flexion,extension,left-right bending,and left-right rotation.The impacts of the three internal fixation techniques on adjacent segment degeneration in the two kinds of fusion were compared and analyzed.RESULTS AND CONCLUSION:(1)In the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw group showed a reduced range of motion on adjacent segments(L3-L4,L5-S1)under six loading conditions compared to both the cortical bone trajectory screw group and traditional bone trajectory screw group.Specifically,the modified cortical bone trajectory screw group significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared to the traditional bone trajectory screw group(P=0.005),while the stress on the intervertebral disc in the inferior adjacent segment(L5-S1)exhibited greater dispersion.Similarly,the cortical bone trajectory screw group also significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared with the traditional bone trajectory screw group(P=0.03).(2)Compared with transforaminal lumbar interbody fusion,the three internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws)showed a trend of reduced range of motion in the inferior adjacent segment(L5-S1)under six loading conditions.In contrast,the maximum stress on the intervertebral discs in both the superior and inferior adjacent segments(L3-L4,L5-S1)exhibited an increasing trend in the posterior lumbar interbody fusion model.(3)It is concluded that in the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw exhibited superior biomechanical properties in reducing the range of motion at adjacent segments,which may have a beneficial effect on reducing the risk of adjacent segment degeneration.