Abstract:Objective：To investigate the clinical efficacy of three endoscopies combined with biliary stenting and primary closure of the common bile duct in the treatment of choledocholithiasis. Methods：A retrospective cohort study was performed on the clinical data of 380 patients with choledocholithiasis who were admitted to our hospital from January 2013 to January 2016. According to treatment methodology，126 patients were assigned to T-tube drainage group，124 patients to primary closure group，and 130 patients to three endoscopies combined with stenting group. The operation time，postoperative hospital stay，hospitalization cost，incidence of biliary complications，and postoperative liver function were compared between the three groups. Follow-up was regularly performed after surgery by outpatient clinic and telephone interview until January 2018. Results：①Treatment outcomes：there was no significant dif－ference in operation time between the T-tube drainage group，primary closure group，and three endoscopies combined with stenting group（106.66±5.01 vs. 105.52±5.62 vs. 105.50±6.10 min，P >0.05）. The T-tube drainage group and the primary closure group had significantly longer postoperative hospital stay and higher hospitalization cost than the three endoscopies combined with stenting group（7.91±0.83），（7.85±0.70） vs. （5.69±0.77） d，P <0.05；（22 081.43±687.55），（21 930.73±758.35） vs. （19 560.88±828.61） yuan，P<0.05. There was no significant difference in the incidence of bile leaking between the three groups（2 vs. 3 vs. 0 case，P >0.05）. In the three groups，liver function gradually re－covered within 5 to 7 days after surgery. The three endoscopies combined with stenting group and the T-tube drainage group showed similar recovery of liver function，which was significantly faster than that in the primary closure group（P <0.05）. ②Follow-up results：in the 380 patients，364 were followed up for 1 to 24 months. The median follow-up time was 20 months. Patients recovered well and no abdominal pain，jaundice，residual stones，or bile duct stricture was observed. Conclusion：Three endoscopies combined with biliary stenting and primary closure of the common bile duct is safe and feasible in the treatment of choledocholithiasis.

Abstract:Various cells in the bone are strictly regulated to maintain bone homoeostasis. Abnormal regulation leads to many bone diseases such as osteoporosis，osteoarthritis，and delayed fracture healing. MicroRNA，a type of non-coding RNAs，is a key regulator of bone metabolism and involved in the regulation of proliferation，differentiation，and function of bone marrow mesenchymal stem cells，osteoblasts，bone cells，osteoclasts，and chondrocytes，thereby affecting the homoeostasis of bone metabolism. Previous studies have demonstrated that miR-214 affects bone metabolism by targeting genes such as β-catenin，activating transcription factor 4，fibroblast growth factor receptor 1，c-Jun N-terminal kinase，p38，Osterix，and phosphatase and tensin homolog. Moreover，miR-214 has an impact on the development，progression，and prognosis of some bone metabolism diseases such as osteosarcoma and osteoporosis via cell adhesion molecule 1，Rho-associated coiled-coil kinase 1，and other related bone metabolism regulators. Recent studies have shown that two autophagy-related genes，autophagy-related gene 12 and GABAA-receptor-associated protein，are also target genes of miR-214，suggesting that miR-214 may affect bone metabolism by regulating autophagy of bone cells. This article aims to elucidate the regulatory mechanism of miR-214 by reviewing domestic and international literature on miR-214 and bone metabolism

Abstract:Polyetheretherketone（PEEK），a linear aromatic and semicrystalline polymer，has excellent mechanical properties and good wear resistance and corrosion resistance. Furthermore，its elastic modulus is highly close to that of the cortical bone. It is an appropriate implant material in vivo. Since the 1980s，as a new implant material，PEEK has been widely used in several orthopedic surgeries such as interbody fusion，artificial joint replacement，and trauma implantation，and has attracted widespread attention in stomatology. Its clinical application over years shows that the PEEK interbody fusion cage has good stability and high fusion rate；the PEEK artificial joints show good tribological properties，fewer wear particles，and strong biological inertia. PEEK has the advantage of individualized manufacture for trauma implants. Using 3D printing technology，a complex prosthesis can be made more rapidly，safely，effectively，and accurately and the new bone induced by the formed scaffold material is as tough and tensile as the natural bone. PEEK has become a new material in stomatology and has attracted wide attention in the fields of oral prosthetics and oral implants. This article aims to review the progress in the clinical application of PEEK and provide a basis for its clinical application.

Abstract:Objective：To investigate the influence of diabetes on anterior cruciate ligament（ACL） reconstruction in rabbits and the va－lidity of this animal model. Methods：A total of 36 healthy male New Zealand rabbits were randomly divided into groups A and B. The rabbits in group B were given the injection of alloxan 80 mg/kg via the auricular vein，followed by alloxan 120 mg/kg after 48 hours，and those in group A were given an equal volume of normal saline. After a model of diabetes was established，autologous tendon was used for ACL reconstruction. Gross observation，blood glucose，histology，bone mineral density（BMD），micro-CT，and qRT-PCR were used to observe the influence of diabetes on ACL reconstruction. Results：Gross observation showed that group A had smooth surface and homogeneous texture of the tendon graft in the articular cavity，while group B had rough surface，brittle texture，and yellow color of the tendon graft. From after modeling to 8 weeks after surgery，group B had a significant increase in fasting blood glucose and a significantly higher level of fasting blood glucose than group A（P<0.01）. Histological examination showed that at 8 weeks after surgery，group B had significant reductions in the numbers of pancreatic islets and islet cells（P<0.01）. At 4 weeks after surgery，group A had significantly higher BMD values of the bone tunnel and the surrounding area than group B（P<0.01）；at 8 weeks after surgery，both groups had a significant increase in BMD，and there was a significant difference between the two groups（P<0.01）. Micro-CT showed that compared with group B at 4 and 8 weeks after surgery，group A had a significantly smaller cross-sectional area of the bone tunnel than group B（4.544±0.056） mm2，（3.667±0.095） mm2 vs. （4.734±0.044） mm2，（4.247±0.069） mm2，P<0.05. Conclusion：The rabbit model of alloxan-induced diabetes and ACL reconstruction is safe，reliable，economic，and stable. There is a significant reduc－tion in BMD of the bone tunnel and the surrounding area in di－abetic rabbits after ACL reconstruction，which results in de－layed growth of the bone tunnel.

Abstract:Objective：To construct Leucine-rich repeats and transmembrane domains 1（Lrtm1） gene knockout C2C12 cell line using the CRISPR/Cas9 technique and to provide an experimental basis for studying the functions of the Lrtm1 gene. Methods：Three pairs of small guide RNA（sgRNA） targeting the Lrtm1 gene were designed and inserted into the vector pCRISPR-LvSG06，and the recom－binant plasmid pCRISPR-LvSG06 containing sgRNA was packaged by the lentiviral packaging system. Then the C2C12 cells were infected with the virus and screened by puromycin，and RNA was extracted from the screen-positive cells and reversely transcribed into cDNA. The Cas9 primer was designed using the cDNA as the template to verify the expression of Cas9 in C2C12 cells by PCR and to confirm that the C2C12 cells were successfully infected by the virus. Monoclonal cells were collected by the 96-well plate method，and the amplified monoclonal cells were used to extract genomic DNA and investigate the Lrtm1 gene-related sequences for comparison with the wild-type Lrtm1 gene，so as to identify the monoclonal cell line with successful gene knockout. After that，the stable Ltm1 gene knockout cell line was induced to differentiate into myoblasts and its expression of myosin，which was the marker of successful myogenic differentiation，was determined. Besides，the expression of transcription factor PAX7 mRNA and H3K27me3 protein was determined by RT-PCR and Western blot，respectively. Results：The sequencing results showed the successful insertion of the sgRNA into the plasmid vector and Lrtm1 gene knockout in clones A and C. The expression of both myosin protein as the myogenic differentiation marker and PAX7 mRNA as the myo－genic transcription factor decreased，while the expression levels of H3K27me3 protein in both the 72-hour and 96-hour differ－entiation groups were higher than those in the wild-type group. Conclusion：The CRISPR/Cas9 technique can be used for Lrtm1 gene knockout and successfully constructing the Lrtm1 gene knockout C2C12 cell line. Lrtm1 gene knockout can inhibit the myogenic dif－ferentiation of C2C12 cells and the expression of PAX7 mRNA，and the reason for the reduced expression of PAX7 mRNA may be at－tributed to the increased level of H3K27me3.

Abstract:Objective：To investigate the effect of irisin on the osteogenic differentiation of rat bone marrow mesenchymal stem cells （BMSCs） under static force and mechanical strain. Methods：Primary rat BMSCs were isolated and cultured，and a four-point bend－ing force system was used to establish an in vitro model of cell stretch. The activity of alkaline phosphatase（ALP） was measured to analyze the effect of irisin concentration on the osteogenic differentiation of BMSCs under static force and mechanical strain and screen out the optimal concentration of irisin. BMSCs were divided into control group，irisin group（100 ng/mL irisin），mechanical strain group（2 000 με mechanical strain），and irisin+mechanical strain group（100 ng/mL irisin+2 000 με mechanical strain）. Cell counting was performed to observe cell proliferation，qRT-PCR and Western blot were used to measure the mRNA and protein expression of osteogenesis-related markers，and the expression of the P38 and ERK 1/2 MAPK pathways was measured. SPSS 20.0 software was used for statistical analysis. Results：The results of ALP activity showed that under static force and mechanical strain，BMSCs treated with 100 ng/mL irisin had a significant increase in ALP activity（P<0.01）. Cell proliferation assay showed that compared with the control group，the irisin+mechanical strain group had a significantly higher level of proliferation of BMSCs（P<0.05）. The results of qRT-PCR showed that irisin + mechanical strain significantly promoted the expression of os－teogenesis-related markers including Runx2，ALP，COL-I，and OPN（P<0.05），and Western blot showed that irisin+mechanical strain significantly promoted the protein expression of Runx2（P<0.05）. In addition，irisin+mechanical strain promoted the proliferation and osteogenic differentiation of BMSCs，which might be associated with the activation of the P38 and ERK 1/2 MAPK pathways. Conclusion：Irisin can promote the proliferation and osteogenic differen－tiation of BMSCs under static force and mechanical strain，possibly via the P38 and ERK1/2 MAPK pathways.

Abstract:Objective：To investigate the effect of low intensity focused ultrasound（LIFU） on the repair of chronic skeletal muscle in－jury in rats. Methods：An impactor was used to establish a rat model of chronic skeletal muscle injury，and then the rats were divided into ultrasound group and control group. The rats in the ultrasound group were given LIFU once a day for 14 consecutive days，and those in the control group were given sham treatment. Tissue samples of the injured area were collected on days 3，10，and 21 of treatment，and HE staining was used to observe histological changes. Immunohistochemistry was used to measure the expression of Myf-5 and α-actinin；image analysis software was used to measure average optical density（AOD）；real-time quantitative polymerase chain reaction was used to measure the mRNA expression of MyoD. Tissue repair was also evaluated. Results：HE staining showed that necrotic muscle fibers were gradually replaced by newly formed muscle fibers in ordered arrangement in the ultrasound group，while the formation of fibrous tissue，inflammatory cell infiltra－tion，and marked muscle fiber atrophy were seen in the control group. Compared with the control group on days 3，10，and 21 of treatment，the ultrasound group had higher expression of α-actinin（0.270±0.026/0.244±0.011/0.222±0.031 vs. 0.234±0.008/0.214±0.020/0.203±0.023，t=2.963，2.865，and 1.073，P=0.018，0.027，and 0.317） and Myf-5（0.291±0.050/0.246±0.015/0.166±0.021 vs. 0.225±0.023/0.211±0.025/0.161±0.016，t=2.691，2.726，and 0.369，P=0.027，0.032，and 0.722） and higher mRNA expression of MyoD（5.613±0.379/3.276±0.261/1.810±0.200 vs. 4.465±0.397/2.807±0.356/1.712±0.280，t=4.679，2.377，and 0.634，P=0.002，0.048，and 0.546），with statistical signifi－cance on days 3 and 10（P<0.05）. Conclusion：LIFU can promote the regeneration and repair of chronic skeletal muscle injury in rats.

Abstract:Objective：To investigate the expression of bone morphogenetic protein 9（BMP9） and epidermal growth factor receptor （EGFR） and the number of osteoblasts and osteoclasts in local tissues in the nonunion microenvironment，and to provide a basis for the etiology and treatment of nonunion. Methods：Twelve 3-month-old healthy New Zealand white rabbits were selected as exper－imental group to develop an animal model of nonunion and six healthy New Zealand white rabbits of the same age were selected as control group. X-ray examination was used to verify the success of modeling. Western blot and immunohistochemistry were used to determine the expression of BMP9 and EGFR in local tissues. Hematoxylin-eosin（HE） staining and tartrate-resistant acid phos－phatase（TRAP） staining were used to count osteoblasts and osteoclasts. Results：X-ray examination indicated that the animal model of nonunion was successfully developed. Western blot and immunohistochemistry showed that the expression of BMP9 and EGFR was significantly reduced from the early stage to the late stage of fracture healing；the expression of BMP9 in the nonunion microen－vironment was significantly lower than that of the control group，while the expression of EGFR was not significantly different from that of the control group. HE staining and TRAP staining showed that the number of osteoblasts was significantly reduced from the early stage to the late stage of fracture healing，and the decrease in osteoblasts in the nonunion microenvironment was greater than that in the control group；however，there was no significant difference in the number of osteoclasts between the experimental group and the control group in both early and late stages of fracture healing. Conclusion：The development of bone nonunion may be associ－ated with decreased expression of BMP9 and EGFR and number of osteoblasts in local tissues.

Abstract:Objective：To investigate the molecular mechanism of bone trabeculae in the development and progression of osteonecrosis of the femoral head（ONFH） and biomarkers for the diagnosis and prediction of ONFH. Methods：Bone trabecular tissue was collected from 4 patients with ONFH（experimental group） and 4 patients with femoral neck fracture（control group），and transcriptome sequencing was performed to screen out differentially expressed genes. These genes were analyzed using bioinformatics software to predict possible biological processes and signaling pathways involving these genes. Results：High-throughput sequencing identified 1527 differentially expressed genes，with 696 upregulated genes and 831 downregulated genes，and there were significant reductions in the expression of lipocalin 2（LCN2） and peroxisome proliferator-activated receptor-γ（PPARγ） in bone trabecular tissue. The gene ontology analysis showed that the differentially expressed genes were mainly enriched in extracellular matrix（ECM） and extra－cellular structural tissue. The kyoto encyclopedia of genes and genome（KEGG） analysis showed that the differentially expressed genes were mainly enriched in ECM-receptor interaction and the PPARγ signaling pathway. Conclusion：This study shows that LCN2 affects the development of ONFH by regulating lipid metabolism and osteogenic differentiation，which provides a clue for exploring the molecular mechanism of ONFH and related diagnostic biomarkers.

Abstract:Objective：To investigate the value of blood neutrophil gelatinase-associated lipocalin（NGAL），osteoprotegerin（OPG），28-joint disease activity score（DAS28），and receptor activator of nuclear factor-kappa B ligand（RANKL） in predicting osteoporosis in patients with rheumatoid arthritis（RA）. Methods：A total of 119 RA patients were enrolled as RA group，among whom 51 had osteo－porosis in addition to RA，and 68 healthy individuals were enrolled as control group. ELISA was used to measure NGAL，OPG（an index for bone formation），and RANKL（an index for bone resorption） for both groups，and bone mineral density（BMD），DAS28，and clinical and laboratory data were recorded in detail. Results：Compared with the control group，the RA group had significantly higher serum levels of NGAL and RANKL（both P=0.000） and significantly lower serum OPG level，OPG/RANKL ratio，and BMD（all P=0.000）. Compared with those without osteoporosis，the RA patients with osteoporosis had sig－nificantly higher serum NGAL（152.12±28.34 ng/mL vs. 124.50±18.52 ng/mL，P=0.000），serum RANKL level（112.23±18.45 pmol/L vs. 103.89±14.14 pmol/L，P=0.008），and DAS28 score（4.21±0.56 vs. 3.52±0.70，P=0.000），as well as significantly lower serum OPG（114.35±17.00 ng/L vs. 120.56±15.35 ng/L，P=0.039），OPG/RANKL ratio（1.06±0.24 vs. 1.18±0.24，P=0.006），and BMD（-3.73±0.69 vs. -0.57±0.76，P=0.000）. Spearman correlation analysis showed that NGAL and DAS28 were positively correlated with the severity of BMD（rs=0.532 and 0.437，P=0.000 and 0.000），and such correlation had a certain value in the early diagnosis of osteoporosis in RA patients. The area under the receiver operating characteristic curve showed that DAS28 with a cut-off value of 4.11（a sensitivity of 68.6% and a specificity of 77.9%），NGAL with a cut-off value of 148.80 ng/mL（a sensitivity of 60.8% and a specificity of 89.7%），and RANKL with a cut-off value of 100.77 pmol/L（a sensitivity of 64.7% and a specificity of 54.4%） helped with the diagnosis of osteoporosis in RA patients. Conclusion：Serum levels of the inflammatory markers NGAL and RANKL and DAS28 score at their respective cut-off values can help with the diagnosis of osteoporosis in RA patients. They also have a certain clinical value in adjustment of treatment regimens and early intervention of osteoporosis.

Abstract:Objective：To investigate the main factors for the postoperative survival rate of elderly patients with femoral intertrochanteric fracture in Xinjiang，China through a retrospective analysis of their clinical data after surgery. Methods：A retrospective analysis was performed for the clinical data of 131 patients who underwent surgical treatment in The First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2017. The Kaplan-Meier method was used to calculate survival rates at 6 months，1 year，3 years，and 5 years after surgery. Cumulative survival rate was calculated and survival curves were plotted. A univariate analysis was performed. The log-rank test was used for comparison between groups，and the Cox regression analysis was used for the multivariate analysis. Results：The survival rates at 6 months，1 year，3 years，and 5 years after surgery were 87.0%（95%CI＝81.3%-92.7%），80.6%（95%CI＝73.7%-87.5%），65.1%（95%CI＝55.7%-74.5%），and 52.1%（95%CI＝37.4%-66.8%），respectively. The univariate analysis showed that age（ ?字2=18.190，P=0.000），number of chronic comorbidities（ ?字2=36.142，P=0.000），presence of nervous system disease （ ?字2=4.093，P=0.043），presence of renal insufficiency（ ?字2 =11.992，P=0.001），preoperative albumin level（ ?字2 =3.872，P=0.049），Ameri－can Society of Anesthesiologists score（ASA）（ ?字2=7.369，P=0.025），length of stay in the intensive care unit（ICU）（ ?字2=24.474，P=0.000） were influencing factors for the postoperative survival rate of elderly patients with femoral intertrochanteric fracture. The multivariate analysis showed that ≥3 chronic comorbidities（hazard ratio[HR]=5.133，95%CI＝2.690-9.790，P=0.000） and a length of stay in the ICU of ≥36 hours（HR=9.229，95%CI＝2.546-33.457，P=0.001） were independent risk factors for poor postoperative prognosis of elderly patients with femoral intertrochanteric fracture. Conclusion：There are various influencing factors for the postoperative survival rate of elderly patients with femoral intertrochanteric fracture. With reference to local medical conditions and patient’s individual conditions，physicians should strengthen multidisciplinary collaboration and select appropriate treatment plans，so as to improve postoperative quality of life，prolong survival time，and improve prognosis.

Abstract:Objective：To investigate the clinical effect of Salter osteotomy combined with femoral osteotomy in the treatment of Tonnis type Ⅱ developmental dysplasia of the hip. Methods：A retrospective analysis was performed for the clinical data of 52 children（57 hips） with Tonnis type Ⅱ developmental dysplasia of the hip who underwent surgical treatment in our hospital from January 2010 to December 2015，and among these children，28（33 hips） underwent Salter osteotomy combined with femoral osteotomy and 24（24 hips） underwent Salter osteotomy alone. A comparative analysis was performed for the two groups. Results：All children obtained follow-up，with a mean follow-up time of 26.8 months（range 12-64 months）. At the last follow-up，the Salter osteotomy-femoral osteotomy combination group had an acetabular index（AI） of 18.1°±5.2°，a center edge（CE） angle of 36.3°±36.1°，and a Sharp angle of 41.4°±4.7°，while the Salter osteotomy group had an AI of 15.7°±4.8°，a CE angle of 37.8°±11.6°，and a Sharp angle of 40.1°±5.0°. There was a significant difference in the incidence rate of femoral head necrosis between the Salter osteotomy-femoral osteotomy combination group and the Salter osteotomy group[2 hips（2/33） vs. 6 hips（6/24）， ?字2=4.131，P=0.042]. According to the Severin radiological classification，in the Salter osteotomy-femoral osteotomy combination group，15 hips were excellent，11 hips were good，6 hips were fairly good，and 1 hip was poor，while in the Salter osteotomy group，5 hips were excellent，14 hips were good，5 hips were fairly good，and no hip was poor；there was no significant difference between the two groups（Z=-1.277，P=0.202）. According to McKay’s hip function evaluation criteria，in the Salter osteotomy-femoral osteotomy combination group，17 hips were excellent，11 hips were good，5 hips were fairly good，and no hip was poor，while in the Salter osteotomy group，13 hips were excellent，7 hips were good，4 hips were fairly good，and no hip was poor；there was no significant difference between the two groups（Z=-0.107，P=0.915）. Conclusion：Salter osteotomy combined with femoral osteotomy has a good clinical effect in the treatment of Tonnis type Ⅱ developmental dysplasia of the hip and can effectively reduce the incidence rate of femoral head necrosis.

Abstract:Objective：To investigate the effect of Fracture Risk Assessment Tool（FRAX） combined with dual-energy X-ray absorp－tiometry（DXA） in predicting fractures in patients with osteoporosis. Methods：A retrospective analysis was performed for the clinical data of 3 000 patients with osteoporosis who were admitted to our hospital from January 2016 to January 2019，and all patients under－went FRAX assessment and DXA examination. The risk of fractures determined by FRAX was compared between male and female patients. Bone mineral density（BMD） in the anterior，posterior，and lateral positions of L2-4，detection rate of fractures in the anterior，posterior，and lateral positions of L2-4，and outcomes of fractures at different sites were recorded for patients in different ages. Results：There was no significant difference in the risk of hip fracture determined by FRAX between male and female patients（P>0.05），and female patients had higher risk of fractures at each site than male patients（P<0.01）. Among the 3 000 patients with an－terior and posterior BMD measurements，529 patients had a T value of >-1.0 s，1 426 patients had a T value of ≤-1.0 s and >-2.0 s，572 patients had a T value of ≤-2.0 s and >-2.5 s，and 455 patients had a T value of ≤-2.5 s. Among the 3 000 pa－tients with lateral BMD measurements，424 patients had a T value of >-1.0 s，717 patients had a T value of ≤-1.0 s and >-2.0 s，808 patients had a T value of ≤-2.0 s and >-2.5 s，and 1 181 patients had a T value of ≤-2.5 s. The detection rates of fractures at the anterior and posterior positions of L2-4 were 34.80%（T value≤-2.0 s） and 15.60%（T value≤-2.5 s），respectively，and the detection rates of fractures at the lateral position were 57.60%（T value ≤-2.0 s） and 39.37%（T value≤-2.5 s），respectively. Of all 3 000 patients，348 had spinal fractures，622 had hip fractures，1 154 had wrist fractures，and 876 had femoral neck fractures，and there were no significant differences in the T val－ues of the anterior/posterior and lateral positions between the patients with fractures at different sites（P>0.05）. Conclusion：FRAX has a good effect in evaluating fractures in patients with osteoporosis，with a better effect in female patients than in male pa－tients. DXA has a good predictive effect in patients with osteoporosis，and a T value of ≤-2.0 s can be used as a standard value for the prediction of fracture.

Abstract:Objective：To investigate the postoperative X-ray change of simple humeral bone cysts with different activity levels and its association with prognosis and clinical significance. Methods：The clinical data of children with humeral bone cysts who underwent surgical treatment in our hospital from January 2012 to April 2018 were collected，and the association between postoperative X-ray change of lesion and prognosis was analyzed in children in the active or latent stage of the disease. The Neer standard was used to evaluate activity level and treatment outcome，and a statistical analysis was performed. Results：A total of 66 children were enrolled and they were followed up for （22.05±4.34） months. Among these children，38 were in the active stage，among whom 6 achieved com－plete response，13 achieved partial response，15 had no response，and 4 experienced recurrence；28 were in the latent stage，among whom 27 achieved complete response and 1 achieved partial response. There was a significant difference in cure rate between the active group and the latent group[50%（19/38） vs. 100%（28/28）， ?字2=19.660，P=0.000]. A total of 19 children in the active group and 28 children in the latent group achieved complete or partial response，and there was a difference in healing time between the active group and the latent group[（11.47±3.65） months vs. （8.32±2.26） months，t=1.779，P=0.082]. Among the 38 active lesions，16 changed into latent lesions after surgery and all of them were cured，while among the 22 persistently active lesions，only 3 were cured（?字2=24.290，P=0.000）. Conclusion：Active lesions of humeral bone cysts tend to have a poor prognosis than latent lesions，and the active lesions that change into latent lesions after surgery tend to have a good prognosis. Patients in the active stage should be closely followed up in clinical practice，and individualized treat－ment should be given based on imaging features and changes.

Abstract:Objective：To preliminarily explore the feasibility of underwater low intensity pulsed ultrasound（LIPUS） device，and to study its effect on early biochemical markers of bone metabolism in aged mice. Methods：A total of 44 female C57BL6 mice were randomly divided into sham control group and ultrasound group（both groups were divided into 12-14 month subgroup and 20-23 month subgroup）. An underwater LIPUS device was constructed and used for irradiation in the corresponding groups. A theoretical simulation of the underwater LIPUS device was carried out using COMSOL 5.3 software，and a sound pressure distribution map was drawn. Orbital blood samples were collected from the mice and tested for serum levels of calcium（Ca） and phosphorus（P） using an automatic biochemical analyzer；the levels of bone alkaline phosphatase（BALP） and β isomer of C-terminal telopeptide of type I col－lagen（β-CTX） were determined by enzyme-linked immunosorbent assay. Results：The underwater LIPUS was able to penetrate the cortical bone with sound pressure distributed into the medullary cavity. Compared with the mice aged 12 to 14 months，the mice aged 20 to 23 months had no significantly different serum levels of Ca，P，and β-CTX（P=0.611，0.660，and 0.855，respectively），but had a significantly reduced BALP level（4.35±1.87 vs. 2.24±0.70，P=0.002）. Compared with the sham control group，the ultrasound group had a significantly reduced serum Ca level（12-14 month subgroup：9.59±0.30 vs. 8.42±0.29，P=0.000；20-23 month subgroup：9.82±0.32 vs. 8.86±0.64；P=0.000），a significantly increased serum P level（12-14 month subgroup：8.99±0.76 vs. 10.33±1.09，P=0.014；20-23 month subgroup：8.49±0.72 vs 10.17±1.17，P=0.002），a significantly increased expression level of BALP（12-14 month subgroup：4.35±1.84 vs. 6.17±1.09，P=0.006；20-23 month group：2.24±0.70 vs. 5.05±0.94，P=0.000），and a significantly decreased expression level of β-CTX（only in the 20-23 month subgroup：189.1±57.94 vs. 114.8±19.72，P=0.047）. Conclusion：It is feasible to construct an underwater LUPUS device，and it can effectively improve the early biochemical markers of bone metabolism in aged C57BL6 mice.

Abstract:Objective：To investigate whether the dislocation sign on knee magnetic resonance imaging（MRI） can be used to predict excessive femoral anteversion in patients with patellar dislocation. Methods：A retrospective analysis was performed on the clinical data of 35 patients（4 males and 31 females） with patellar dislocation who attended our hospital from January 2016 to July 2018. The mean age was 21.3 years. The femoral anteversion angle was 28.3°±8.3°. The tibial torsion angle was 29°±8.9°. The femorotibial index was -1.3±11.1. The dislocation sign on knee MRI was defined as malalignment between the lateral wall of intercondylar fossa of the femur and the lateral intercondylar eminence of the tibial plateau. The number of frames with dislocation sign was 1.49±1.25. Results：Dislocation sign was observed in 25 of the 35 patients. There was a significant difference in femoral anteversion angle between the patients with dislocation sign and those without dislocation sign（P<0.05）. The femoral anteversion angle was significantly correlated with the number of frames with dislocation sign on knee MRI（P<0.05）. Conclusion：Dislocation sign can be identified on knee MRI and can be a predictor of excessive femoral anteversion in patients with patellar dislocation. The femoral anteversion angle can be es－timated by the number of frames with dislocation sign.

Abstract:Objective：To optimize the nailing path at trapezium of mineral external fixation for treating the fracture at the basilar of the first metacarpal，which can build more stable fixation and present safe and accurate operation. Methods：We measured the values of trapezium at multidimension by researching the computed tomography（CT） images of the bone at the multi-planer reconstruction （MPR） images，and analyzed them about the optimized nailing path design and feasibility. Results：The CT values of 60 people’s nor－mal trapezium were measured，including 30 men and 30 women with average age of 42.3. The radialis width of trapezium is （13.46±1.13） mm，middle altitude is （11.43±1.18） mm，altitude above shorten sagittal diameter is （7.38±0.98） mm，sagittal length is （14.59±1.63） mm. The measured values were used in locating nail tract. Conclusion：Most of the sizes of trapezium can meet the requirement of the optimization of nailing path；most of the measured values of trapezium can be used to evaluate the safe range of nail tract and provide guidance for the operation.

Abstract:Objective：To develop a scoring system for rapid outpatient differential diagnosis of SM and STB and to improve outpatient diagnostic accuracy. Methods：The records of 141 patients who had a pathological diagnosis of SM or STB from 2014 to 2016 in our department were retrospectively reviewed. The following clinical and imaging data that they provided in outpatient were recorded：age，gender，relative history，number of the vertebral lesions，the distribution of vertebral lesions，the involved vertebral element，the intervertebral disc was involved or not，if there was a sequestra formation and if there was a soft tissue component. Then a multivariate logistic regression analysis was conducted，and the rapid outpatient differential diagnosis scoring system was established. Results：Among the total 141 patients，82 cases were diagnosed with SM and 59 cases were STB. Multivariate logistic regression analysis showed that age，gender，relative history and a soft tissue component can hardly provide accurate diagnostic information. The rapid outpatient differential diagnosis scoring system was based on four characteristic imaging features namely the distribution of vertebral lesions，the involved vertebral element，the intervertebral disc was involved or not，and if there was a sequestra formation. SM showed a statistic significant higher score than did STB（6.09 vs. 1.56，t=-18.157，P=0.000）. The sensitivity and specificity of rapid outpatient differential diagnosis scoring system were 86.44% and 96.34%，respectively. Conclusion：The differential diagnosis scoring system shows satisfactory sensitivity and specificity in rapid outpatient diagnosis of SM and STB. Spinal lesions with the score of 0 to 3 are STB，and the score of 4 to 7 are SM. This scoring system still needs further revision and improvement.

Abstract:Objective：To investigate the changes in the risk of deep venous thrombosis（DVT） in patients undergoing hip arthroplasty in different stages and related influencing factors. Methods：The method of convenience sampling was used. A total of 209 patients who underwent hip arthroplasty in a grade A tertiary hospital in Chongqing，China were enrolled，and a questionnaire of general informa－tion，Autar Scale，Barthel scale，and Charlson comorbidity index were used for observation on the day of admission，the day of surgery，and the day of discharge and at one month after discharge. Results：The total score of DVT risk assessment ranged from 12.31 to 15.42 at different time points；this score started to increase since the day of admission，reached the peak on the day of surgery，and then tended to decrease，but the risk of DVT on the day of discharge was higher than that on the day of admission. The multivariate linear regression analysis showed that activities of daily living was the most effective predictive factor for DVT on admission（β=-0.460，P<0.05） and disease type was an independent influencing factor for DVT on admission（ β=0.194，P=0.000）；body mass index（BMI） was an important risk factor for DVT from after surgery to one month after discharge（ β=0.315，0.302，and 0.251，all P<0.05）；age，times of hospitalization，and Charlson comorbidity index were important predictive factors for DVT from admission to one month after discharge（β=0.229，β=0.098，β=0.258；β= 0.383，β=0.133，β=0.423；β=0.273，β=0.114，β=0.115，β=0.313；β=0.217，β=0.115，β=0.223，all P<0.05），and time to ambulation after surgery was also an influencing factor for DVT（β=0.258 and 0.278，P<0.05）. Conclusion：Patients undergoing hip arthroplasty have intermediate to high risk of DVT from admission to one month after discharge. Old age，obesity，Charlson comorbidity，history of multiple hospital－izations，and a long time to ambulation after surgery are risk fac－tors for DVT. Preventive measures should be taken according to the risk factors in different periods of time，and the medical staff should pay attention to the patients with a high risk of DVT at the time of discharge. Comprehensive preventive measures for DVT should be taken seriously and follow-up after discharge should be strengthened.

Abstract:Objective：To investigate the functional characteristics of the obitofrontal cortex in adolescent depressive patients by rest－ing-state functional magnetic resonance imaging（rs-fMRI）. Methods：A total of 71 adolescent depressive patients meeting DSM-IV diagnostic criteria were taken as case group，and 44 age-and sex-matched healthy adolescents as control group. Both group were scanned by 3.0T MRI scanner，and rs-fMRI data and T1-weighted images were obtained and processed with DPABI. Data were analyzed by amplitude of low-frequency fluctuation（ALFF） to obtain resting-state information between 0.01 to 0.1 Hz in orbital frontal cortex. Final results were subjected to permutation test and corrected by threshold-free cluster enhancement（TFCE）. Region of interest（ROI） was drawn for each subject based on the significantly changed brain area in ALFF. Functional connectivity（FC） was performed between ROI and bilateral thalamus and 12 limbic areas：bilateral amygdala，anterior-，middle- and posterior cingulate cortex，and hippocampus. Results：Compared with the healthy group，zALFF value of the left obitofrontal cortex reduced in the depression group（t=-2.23，P<0.05）. FC value showed that FC of the obitofrontal cortex and left thalamus decreased（P=0.024）. Conclusion：Compared with the healthy group，functional activities of the obitofrontal cortex show obvious abnormalities in patients with adolescent depression，which may be correlated with the pathophysiological mechanism of adolescent depression.

Abstract:Objective： The purpose of this in vitro test was to investigate the fracture resistance of post and crowned maxillary premolar with various ferrule configurations. Methods：According to the partial ferrule location, thirty two maxillary premolar after endodontical treatment were assigned to four groups：（Group A：with a circumferential ferrule；Group B：with a complete palatal ferrule；Group C：with a complete buccal ferrule；Group D：with a complete proximal ferrule）. All specimens were reconstructed with fiber posts，resin cores，and metal crowns，then specimens were mounted and loaded at 45° to the long axis，at the top 1/3 of the lingual surface of the buccal cusp in a universal testing machine until fracture occurred，the speed set at 1.0 mm/min. Results：The mean fracture load was （826.3±183.1），（587.8±142.4），（406.1±189.7），（486.3±317.4） N respectively. One-way ANOVA analysis showed statisti－cally significant difference（P<0.05） existed between those groups，the anti-fracture ability of Group A was significantly higher than other groups B，C and Group D（P=0.037，0.001，0.004）. No significant differences were found between the other groups（P>0.05）. The predominant fracture mode was an oblique fracture at cervical one-third observed from palatal to buccal side，while only one specimen fracture line was observed at root one-third in Group A. Conclusion： Post and cored crown with a complete ferrule could significantly improve the fracture resistance of the pulpless tooth. When the residual dentinal tissue is not enough，preserve more palatal dentinal tissue may enhance the fracture resistance by protecting the in－tegrity of the adhesive layer between the dentin and resin.

Abstract:Objective：To investigate the value of carotid artery sonography in screening for the high-risk population of stroke. Methods：A total of 500 patients at a high risk of stroke who were admitted to our hospital from March 2015 to March 2017 were enrolled as subjects，and their medical history was recorded. Carotid artery color Doppler ultrasound was performed for all patients，and risk factors for carotid plaque or stenosis in the high-risk population of stroke were analyzed，as well as the influence of age on the incidence rates of carotid plaque and stenosis. Results：The results of carotid artery sonography showed that among the 500 patients at a high risk of stroke，180（36.00%） had carotid intima-media thickening and 141（28.20%） had the formation of carotid plaque. The proportion of patients with carotid intima-media thickening，formation of carotid plaque，and carotid stenosis significantly increased with age（P<0.05）. There was a significant difference in the proportion of patients with the formation of carotid plaque between male and female patients（P<0.05）. The logistic regression analysis showed that hypertension，hyperlipidemia，lack of exercise，and a family his－tory of stroke were risk factors for high risk of stroke or carotid intima-media thickening. Conclusion：In the population at a high risk of stroke，the incidence rates of carotid intima-media thickening and atherosclerotic plaques tend to increase with age. Carotid artery color Doppler ultrasound has a high value in the risk assessment of stroke and thus holds promise for clinical application.

Abstract:Objective：To observe the incidence and types of adverse events after lifting and thrusting treatment with different needles for cervical spondylotic radiculopathy（CSR），and to evaluate the safety of lifting and thrusting manipulation with different needles，especially small needle knife，in the treatment of CSR. Methods：A total of 120 CSR patients were randomly divided into acupotomy group（n=60） and acupuncture group（n=60）. The incidence and severity of adverse events，particularly pain，were assessed after a single lifting and thrusting manipulation with two needles of the same diameter. Results：Forty-two patients of the acupotomy group experienced pain after treatment，while only 4 of the acupuncture group experienced this symptom，with a significant difference in the number of cases between the two groups（P=0.000）. Generalized fatigue was seen in 7 patients in the acupotomy group and 1 patient in the acupuncture group，with a significant difference in the number of cases between the two groups（P=0.028）. Pain and fatigue all disappeared within 3 days. After acupotomy，the common local adverse reaction was pain and sore and swelling，usually next to the cervical spinous process or at the transverse process or tubercles，and the common systemic adverse reaction was fatigue；headache and heartburn were seen in some cases. Conclusion：In the lifting and thrusting treatment of CSR，acupotomy is more likely to cause adverse events than acupuncture，but it is generally safe. Treatment guidelines for acupotomy are needed to avoid medical disputes.

Abstract:Objective：To analyze the influence of the red blood cell（RBC） lysing solution on the comparative counting of CD34+ cells. Methods：A total of 101 peripheral blood stem cell collections were collected and stained by CD34-PE and CD45-FITC monoclonal antibodies. Then the RBCs were lysed by two commercially available lysing solutions，FACSTM lysing solution（FACS） and Optilyse C lysing solution（Optilyse C） and one self-prepared lysing solution. The washing procedure and ISHAGE gate strategy were used to de－tect the relative numbers of CD34+ cells，lymphoid cells，granulocytes，and monocytes，the percentage of CD45+ cells，and the various types of cell forward scatter（FSC） and side scatter（SSC） signals. Results：The percentage of CD34+ cells was the lowest in the FACS-treated samples，while the highest in self-prepared lysing solution（0.49±0.43 vs. 0.67±0.50 vs. 0.73±0.66，P=0.000）. The percent－age of CD45+ cells in the samples treated by FACS was much higher than that in the samples treated by Optilyse C and self-prepared lysing solution respectively（t=142.500，P=0.000）. The percentage of lymphocytes（F=35.340，P=0.000） had significant differences in samples treated by the three lysates solutions respectively，however，there was no statistically significant difference for the percentage of granulocytes（F=0.610，P=0.540） and monocytes（F=1.590，P=0.210）. After FACS treatment，the signal intensities of FSC and SSC of CD34+ cells and lymphocytes were weaker than those of the Optilyse C and self-prepared lysing solution treatments，while the SSC signals of granulocytes and monocytes were the strongest after FACS lysate treatment and were the weakest after Opti－clese C treatment. In addition，there was no correlation between the number of leukocytes after mobilization and the percentage of CD34+ cells（r=0.108，P=0.312）. Conclusion：The difference in the relative count of CD34+ cells caused by the RBC lysate may be related to the proportion of CD45+ cells，that is，the acquired effi－cient cell numbers. The effect of lysate on cell morphology is related to the significant difference in lymphocyte ratio. As different RBC lysates do have adverse effects on the relative counts of CD34-positive cells，the choice of RBC lysates reagents for the flow cytometry or counting should be careful.

Abstract:Objective：To identify the prevalence of cerebral lesions in maintenance hemodialysis（MHD） patients without cognitive im－pairment，analyze the potential risk factors，and preliminarily investigate the relationship between the cerebral lesions and their cognitive function/depression. Methods：A cross-sectional study was conducted on 30 MHD patients without cognitive impairment and 30 healthy controls，and the brain magnetic resonance imaging findings were compared between the two groups of patients. Demographic information and laboratory data were collected. The Montreal cognitive assessment（MoCA） and Beck depression inventory（BDI） were used to evaluate their cognitive function and depression. A logistic regression analysis was performed to identify the risk factors for cerebral lesions. The Mann-Whitney U test was used to evaluate the differences in cognitive function and depression between the MHD patients with and without cerebral lesions. Results：Among the 30 MHD patients without cognitive impairment，16（53.33%） had cerebral lesions，including lacunar infarctions in 11（36.67%） cases，leukoencephalopathy in 6（20.00%） cases，and multiple ischemic lesions in 7（23.33%） cases，versus 2 cases of cerebral lesions in the control group（ χ2=15.556，P=0.000）. The logistic regres－sion analysis showed that serum phosphate was an independent risk factor for lacunar infarctions（OR=12.297，95%CI=1.106 to 136.737，P<0.05） and multiple ischemic lesions（OR=77.492，95%CI=1.571 to 3 822.433，P<0.05） in MHD patients without cognitive impairment. The MoCA score was significantly higher in MHD patients without cerebral lesions than in those with cerebral small vessel diseases（lacunar infarctions and multiple ischemic lesions，Z=-2.10，P=0.036） and those with leukoencephalopathy（Z=-2.13，P=0.038），while the BDI score was not significant between them. Conclusions：More than half of the MHD patients without cognitive impairment have cerebral lesions，such as lacunar infarc－tions，multiple ischemic lesions，and leukoencephalopathy. Serum phosphate is an independent risk factor for cerebral small vessel diseases. Cerebral small vessel diseases and leukoencephalopathy are associated with cognitive function decline in MHD patients.

Abstract:Objective：To investigate the clinical features and prognosis of Hirschsprung’s disease（HD） in infants，and to guide early clinical diagnosis and treatment. Methods：A retrospective analysis was performed for the clinical data and postoperative follow-up data of 159 infants（aged 0-90 days） with HD who underwent surgical treatment in our department from 2011 to 2016. Results：The male/female ratio was 8.35∶1 among all 159 infants with HD；as for the manifestation of disease onset，94.3% had abdominal disten－sion，76.1% had vomiting，71.4% had delayed discharge of meconium，and 44.0% had constipation. The diagnostic accuracies of barium enema（BE），anorectal manometry（ARM），and rectal suction biopsy（RSB） were 84.8%，93.2%，and 96.6%，respectively，and there was a significant difference in diagnostic accuracy between these auxiliary examinations（ χ2=13.872，P=0.001）. There were no signifi－cant differences between pathological groups in the diagnostic accuracies of BE（ χ2=2.273，P=0.518），ARM（ χ2=1.297，P=0.730），and RSB（ χ2=1.355，P=0.716）. All infants were cured after surgical treatment and were then discharged. The mean postoperative hospital stay was 9.42 days，and major postoperative complications included enterocolitis（10.7%），incision infection（2.5%），and rupture of incision（1.3%）. Conclusion：Major clinical manifestations of HD in infants include abdominal distension and vomiting. Since these clinical manifestations lack specificity，ARM，BE，and RSB help with early diagnosis. Early surgery has a good clinical effect with few complications and rapid recovery.

Abstract:Objective：To investigate the application of contrast enema（CE），anorectal manometry（ARM），and rectal suction biopsy （RSB） in the preoperative auxiliary examination of Hirschsprung’s disease（HD） and its significance. Methods：A retrospective analysis was conducted on 496 children with HD in our hospital based on their medical records including age，auxiliary examination results，and clinical pathology reports. The patients were grouped according to their age and pathological types，and were compared for the sensitivity of the above three preoperative examinations using chi-square test. Results：For comparison between different age groups，the diagnostic sensitivity of RSB and ARM was significantly higher than that of CE in the 0- to 28-day group（n=80 and n=68， ?字2=14.060 and 9.620，P=0.000 and 0.001，respectively）；there were no significant differences in sensitivity between CE，ARM，and RSB in the 28- to 90-day group（P>0.017）；the sensitivity of RSB was significantly higher than that of CE and ARM in the 90-day to 3-year-old group（n=148， ?字2=13.070 and 15.060，P=0.000）；the sensitivity of ARM was significantly higher in the 0- to 28-day group than in the 3-year-old to older age group（ ?字2=8.780，P<0.05）；there were no significant differences in sensitivity between RSB and CE across the four age groups（P>0.05）. For comparison between different groups by pathological types，the diagnostic sensitivity of RSB was significantly higher than that of CE in the short-segment HD group（n=40， ?字2=5.140，P=0.016）；the diagnostic sensitivity of RSB was significantly higher than that of ARM and CE both in the normal-segment HD group（n=197， ?字2=16.060 and 18.050，P=0.000） and in the long-segment HD group（n=70， ?字2=13.070 and 9.090，P=0.000 and 0.001，respectively）；the diagnostic sensitivity of CE was significantly lower in the short-segment HD group than in the normal-segment HD group（ ?字2=8.670，P<0.05）；the diagnostic sensitivity of ARM was significantly lower in the long-segment HD group than in the normal-segment HD group（ ?字2=7.930，P<0.05）；there were no significant differences in the sensitivity of RSB between all the different groups by HD types（P>0.008）；CE examination showed significantly lower accuracy in the long-segment HD group than in the short-segment HD and the normal-segment HD groups in terms of locating the spasmodic segment across four different pathological types of HD（ ?字2=13.880 and 10.330，P<0.05）. Conclusion：CE，ARM，and RSB are commonly used auxiliary examinations in the diagnosis of HD. Comparatively speaking，CE shows a relatively high diagnostic sensitivity for normal-segment HD（with negligible effect of patient’s age） and a relatively high accuracy in locating the spasmodic segment for short-segment and normal-segment HD；ARM shows a relatively high diagnostic sensitivity for normal-segment HD just as CE，with increased sensitivity as patient’s age decreases；the diagnostic sensitivity of RSB is not affected by age，but is relatively low in short-segment HD.