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.

BACKGROUND:The correlation between sacroiliac joint degeneration and lumbar degenerative disease has been analyzed in the literature in the past,but the clinical efficacy and imaging changes after interbody fusion with sacroiliac joint ankylosis in patients with lumbar degenerative disease have not been reported in the literature.OBJECTIVE:To investigate the effect of sacroiliac joint ankylosis on the clinical efficacy and lumbar sagittal regression after L5/S1 single-segment transforminal lumbar interbody fusion in patients with lumbar degenerative disease.METHODS:Thirty-seven patients who underwent L5/S1 segmental transforminal lumbar interbody fusion for lumbar degenerative disease with sacroiliac joint ankylosis between June 2020 and September 2023 in Affiliated Hospital of Xuzhou Medical University were retrospectively analyzed as group A.Thirty-seven patients with lumbar degenerative disease without sacroiliac joint ankylosis who were matched for general information during the same period were selected as controls in group B.Clinical efficacy was assessed using the Oswestry disability index and visual analog scale for lumbar and lower limb pain.The lumbar sagittal parameters included lumbar anterior convexity angle,lumbar partial anterior convexity angle,and lower lumbar anterior convexity angle.Pfirrmann grading was used to assess the degree of preoperative disc degeneration,postoperative endplate damage and screw loosening,and to record the fusion of the operated segments at the final postoperative follow-up visit.RESULTS AND CONCLUSION:(1)There was no statistically significant difference in age,body mass index,bone mineral density,operation time,intraoperative bleeding,preoperative primary diagnosis and postoperative follow-up time between the two groups(P＞0.05).(2)The preoperative Pfirrmann grading of lumbar disc degeneration in group A patients(3.4±0.9)was significantly higher than that of group B(3.1±0.6),and the difference was statistically significant(t=2.059,P=0.044).(3)All patients showed significant improvement in postoperative lumbar sagittal parameters compared with preoperative ones(all P＜0.05).During the follow-up period,there was a loss of correction in patients in group A.There was no statistical difference in the lumbar anterior convexity angle,lower lumbar anterior convexity angle,and local anterior convexity angle at the last follow-up compared with the preoperative period(P＞0.05).The lumbar anterior convexity angle,lower lumbar anterior convexity angle,and local anterior convexity angle in group A were significantly lower than those of group B patients at both preoperative and final follow-up,and the differences were statistically significant(all P＜0.05).(4)There was no statistically significant difference in postoperative endplate injury between the two groups(x2=0.181,P=0.670),and screw loosening was significantly higher in group A than in group B,with a statistically significant difference(x2=4.163,P=0.041).(5)At the last follow-up,the incidence of grade 3 fusion and grade 4 fusion was significantly higher in group A than in group B.The difference in the distribution of fusion grades between the two groups was statistically significant(x2=7.848,P=0.031).(6)The Oswestry disability index and lower limb visual analog scale scores at the last follow-up of both groups were significantly improved compared with the preoperative period(P＜0.05).The visual analog scale scores for low back pain at 3 months after surgery and at the last follow-up of group A were significantly higher than those of group B(t=2.010,P=0.048;t=2.133,P=0.036).(7)It is concluded that regardless of whether it is accompanied by sacroiliac joint ankylosis or not,lumbar degenerative disease patients who undergo interbody fusion with foramen magnum can achieve good therapeutic effects,but lumbar degenerative disease patients with sacroiliac joint ankylosis who undergo interbody fusion with foramen magnum at the L5/S1 segments have a poorer improvement of low back pain than patients without sacroiliac joint ankylosis after the operation.Furthermore,patients with preoperative sacroiliac ankylosis who underwent L5/S1 segmental transforminal lumbar interbody fusion had a low fusion rate and were prone to loss of correction of the lumbar sagittal position.

BACKGROUND:The number of patients receiving total knee arthroplasty has been increasing globally each year.Pain management is a crucial aspect following total knee arthroplasty,as effective pain control can facilitate early mobilization,reduce complications,enhance patient satisfaction,and accelerate the rehabilitation process.OBJECTIVE:To construct a visual map of post-total knee arthroplasty pain,understand the international research status and trends in this field,and provide a reference for future studies.METHODS:Relevant research articles on post-total knee arthroplasty pain were retrieved from the CNKI,WanFang Data,and Web of Science core databases,covering the period from January 2000 to December 2023.The CiteSpace software(version 6.2.3)was used to analyze the annual publication output,authors,institutions,countries,keywords,and references.Utilizing R programming language(version 4.4.1),a database was established to create line charts and bar graphs.RESULTS AND CONCLUSION:(1)Our analysis included 3 796 publications,predominantly in Chinese(3 509 articles)with the remainder in English(287 articles).(2)The United States was the most productive country in English literature,with Harvard University leading institutional output.Guangzhou University of Chinese Medicine was the top publishing institution in Chinese literature.(3)Keyword clustering identified"quality of life,""phobia,"and"acupuncture"as emerging focal points in Chinese literature,while"satisfaction"and"psychological factors"were prominent in English literature over the past five years.Co-occurrence and clustering analysis revealed dense internal connections among institutions,authors,and publications,but sparse external collaborations.(4)The study's bias on visualization analysis may have introduced bias by excluding less influential papers.(5)Regarding research hotspots,domestic research emphasized the efficacy and exploration of analgesic methods,in contrast to international research that focused on pain mechanism subtyping and analgesic drug innovation.Future research is expected to trend towards traditional Chinese medicine for postoperative pain,multimodal analgesia,and the investigation and prevention of pain typing mechanisms.

BACKGROUND:The incidence rate of chronic non-specific neck pain is high and the etiology is unknown.Myofascial pain and deep cervical flexor atrophy are the key factors.Extracorporeal shockwave therapy can improve microcirculation,relieve local pain,and delay the degenerative development of the cervical spine,while motion control training can significantly improve neck muscle strength and endurance and reduce neck pain.However,both methods have limited effectiveness when applied individually.OBJECTIVE:To explore the therapeutic efficacy of extracorporeal shock wave intervention combined with motion control training at the upper trapezius muscle on chronic non-specific neck pain.METHODS:Forty-two patients with chronic non-specific neck pain recruited from Shenyang Sport University were randomly divided into three groups:a shock wave group(n=14),in which extracorporeal shockwave intervention at the upper trapezius muscle was given for 10-15 minutes,once a week for 4 weeks;a training group(n=14),in which motion control training was given for 40-50 minutes,three times a week for 4 weeks;and a combination group(n=14),in which extracorporeal shockwave intervention at the upper trapezius muscle combined with motion control training was performed for 4 weeks.Patients were assessed for pain intensity,cervical spine function,upper trapezius muscle thickness,hemodynamic parameters,and serum interleukin 6 and tumor necrosis factor α levels before intervention,1 week and 4 weeks after intervention.RESULTS AND CONCLUSION:(1)Compared with the pre-intervention period,the visual analogue scale scores and neck disability index in the three groups were lower after 1 and 4 weeks of intervention(P＜0.05),and the visual analogue scale scores and neck disability index in the combination group were lower than those of the shock wave group and the training group(P＜0.05).(2)Compared with the pre-intervention period,the upper trapezius thickness increased in the training group and the combination group after 4 weeks of intervention(P＜0.05);the upper trapezius thickness was greater in the combination group than in the shock wave group and the training group after 4 weeks of intervention(P＜0.05).(3)The shock wave group and the combination group had an increase in the peak systolic velocity of the ascending segment of the transverse carotid artery(P＜0.05)and a decrease in the resistance index(P＜0.05)after 1 and 4 weeks of intervention,while the training group showed an increase in the peak systolic velocity of the ascending segment of the transverse carotid artery(P＜0.05)and a decrease in the resistance index(P＜0.05)after 4 weeks of intervention.The peak systolic velocity of the ascending segment of the transverse carotid artery in the combination group was higher(P＜0.05)and the resistance index was lower(P＜0.05)than those in the shockwave group and the training group after 1 and 4 weeks of intervention.(4)Compared with the pre-intervention period,the levels of interleukin 6 and tumor necrosis factor α were reduced in the shock wave and combination groups after 1 and 4 weeks of intervention(P＜0.05),and in the training group after 4 weeks of intervention(P＜0.05).After 1 and 4 weeks of intervention,the levels of interleukin 6 and tumor necrosis factor α were lower in the combination group than in the shock wave group and the training group(P＜0.05).To conclude,extracorporeal shock wave combined with motion control training for chronic non-specific neck pain significantly reduces pain and improves neck function,and the mechanism of action may be to promote the blood flow velocity at the trigger point,reduce blood flow resistance,reduce the serum levels of interleukin 6 and tumor necrosis factor α,and increase the thickness of the upper trapezius muscle.

OBJECTIVE:Disorders in iron metabolism increase the risk of type 2 diabetes mellitus.Hepcidin play an important role in maintaining iron homeostasis in the body,but its level increases with increased inflammation.Changes in hepcidin and iron homeostasis and the extent of their association with inflammation in people with and without type 2 diabetes mellitus are unknown.Meta-analysis was used to evaluate the effect of inflammation on serum hepcidin and iron metabolism related parameters in patients with type 2 diabetes mellitus.METHODS:CNKI,PubMed,Web of Science and EBSCOhost databases were searched by computer to collect observational studies related to inflammatory index and hepcidin in patients with type 2 diabetes mellitus.The search time was from September 1,2000 to September 30,2024.Three researchers independently screened the literature,extracted data and evaluated the quality of the included literature.Meta-analysis was performed by Review Manager 5.3,Stata 17.0 and GraphPad Prism 8.0.2 software.RESULTS:A total of 15 articles(17 studies)involving 3 159 participants,including 1 357 patients with type 2 diabetes mellitus,were included.Meta-analysis results showed that compared with the control group,patients with type 2 diabetes mellitus had higher levels of serum hepcidin[standardized mean difference(SMD)=0.35,95％confidence interval(CI)(0.05,0.65),P＜0.05],serum ferritin(SMD=0.49,95％CI(0.21,0.78),P＜0.01)and serum transferrin(SMD=0.19,95％CI(0.00,0.37),P＜0.05).Subgroup analysis results indicated that inflammation had a significant effect on serum hepcidin(SMD=0.76,95％CI(0.17,1.34),P＜0.05)and serum ferritin(SMD=0.77,95％CI(0.06,1.47),P＜0.05)in patients with type 2 diabetes mellitus.CONCLUSION:Hepcidin concentration is positively correlated with type 2 diabetes mellitus.Inflammation is one of the risk factors of type 2 diabetes mellitus.Early prevention of inflammation has certain significance in preventing iron metabolism disorder in patients with type 2 diabetes mellitus.

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.