OBJECTIVE: To investigate the impact of bone mass and volume of low-density zones beneath the tibial plateau on the maximum von Mises stresses experienced by the cartilage and meniscus in the knee joint. METHODS: The study included one healthy adult volunteer, from whom CT scans were obtained, and one patient diagnosed with knee osteoarthrisis (KOA), for whom X-ray films were acquired. A static model of the knee joint featuring a low-density zone was established based on a normal knee model. In the finite element analysis, axial loads of 1 000 N and 1 800 N were applied to the weight-bearing region of the upper surface of the femoral head for model validation and subsequent finite element studies, respectively. The maximum von Mises stresses in the femoral cartilage, as well as the medial and lateral tibial cartilage and menisci, were observed, and the stress percentage of the medial and lateral components were concurrently analyzed. Additionally, HE staining, as well as alkaline magenta staining, were performed on the pathological specimens of patients with KOA in various low-density regions. RESULTS: The results of model validation indicated that the model was consistent with normal anatomical structures and correlated with previous calculations documented in the literature. Static analysis revealed that the maximum von Mises stress in the medial component of the normal knee was the lowest and increased with the advancement of the hypointensity zone. In contrast, the lateral component exhibited an opposing trend, with the maximum von Mises stress in the lateral component being the highest and decreasing as the hypointensity zone progressed. Additionally, the medial component experienced an increasing proportion of stress within the overall knee joint. HE staining demonstrated that the chondrocyte layer progressively deteriorated and may even disappear as the hypointensity zone expanded. Furthermore, alkaline magenta staining indicated that the severity of microfractures in the trabecular bone increased concurrently with the expansion of the hypointensity zone. CONCLUSION The presence of subtalar plateau low-density zone may aggravate joint degeneration. In clinical practice, it is necessary to pay attention to the changes in the subtalar plateau low-density zone and actively take effective measures to strengthen the bone status of the subtalar plateau low-density zone and restore the complete biomechanical function of the knee joint, in order to slow down or reverse the progression of osteoarthritis.
Humans ; Finite Element Analysis ; Knee Joint/physiology* ; Tibia/anatomy & histology* ; Cartilage, Articular/physiology* ; Menisci, Tibial/physiopathology* ; Tomography, X-Ray Computed ; Osteoarthritis, Knee/diagnostic imaging* ; Weight-Bearing ; Bone Density ; Adult ; Stress, Mechanical ; Male ; Middle Aged ; Biomechanical Phenomena ; Female

Background::Understanding willingness to undergo pulmonary function tests (PFTs) and the factors associated with poor uptake of PFTs is crucial for improving early detection and treatment of chronic obstructive pulmonary disease (COPD). This study aimed to understand willingness to undergo PFTs among high-risk populations and identify any barriers that may contribute to low uptake of PFTs.Methods::We collected data from participants in the "Happy Breathing Program" in China. Participants who did not follow physicians’ recommendations to undergo PFTs were invited to complete a survey regarding their willingness to undergo PFTs and their reasons for not undergoing PFTs. We estimated the proportion of participants who were willing to undergo PFTs and examined the various reasons for participants to not undergo PFTs. We conducted univariable and multivariable logistic regressions to analyze the impact of individual-level factors on willingness to undergo PFTs.Results::A total of 8475 participants who had completed the survey on willingness to undergo PFTs were included in this study. Out of these participants, 7660 (90.4%) were willing to undergo PFTs. Among those who were willing to undergo PFTs but actually did not, the main reasons for not doing so were geographical inaccessibility ( n = 3304, 43.1%) and a lack of trust in primary healthcare institutions ( n = 2809, 36.7%). Among the 815 participants who were unwilling to undergo PFTs, over half ( n = 447, 54.8%) believed that they did not have health problems and would only consider PFTs when they felt unwell. In the multivariable regression, individuals who were ≤54 years old, residing in rural townships, with a secondary educational level, with medical reimbursement, still working, with occupational exposure to dust, and aware of the abbreviation "COPD" were more willing to undergo PFTs. Conclusions::Willingness to undergo PFTs was high among high-risk populations. Policymakers may consider implementing strategies such as providing financial incentives, promoting education, and establishing community-based programs to enhance the utilization of PFTs.

AIM: To investigate the effects of 0.01% atropine eye drops on macular blood flow density and retinal thickness in children with different degrees of myopia. METHODS: This was a prospective case-control study. Sixty-four patients (112 eyes) diagnosed with myopia for the first time with 0.01% atropine eye drops before and 6 months after medication were investigated with the uncorrected distance visual acuity (UCVA), axial length (AL), spherical equivalent (SE), macular ganglion cell-inner plexiform layer thicknes (mGCIPL) using slit lamp examination and optical coherence tomography (OCT), vascular density in the macular area and the area of the avascular in the fovea using optical coherence tomography angiography (OCTA) . Changes in various indicators before and after medication were compared. RESULTS: Compared with before medication, the AL of the three groups of myopia patients increased significantly (P<0.01), the difference in low to moderate myopia group was significantly smaller than that in high myopia group. Compared with before medication, SE increased in all three groups of myopia patients, yet there was no statistically significant difference in the low - grade myopia group (P>0.05). The difference was statistically significant between the moderate myopia group and the high myopia group (P< 0.01). Compared with before medication, there was no change in intraocular pressure (IOP) among the three groups of myopic patients (P>0.05). After 6 months of medication, the central circle macular vessel density (cCVD) increased in the low myopia group and moderate myopia group (P<0.01), there was no statistically significant difference in the high myopia group (P>0.05). Before and after medication, there was no significant difference in outer circle macular vessel density (oCVD), inner circle macular vessel density (iCVD), and whole circle macular vessel density (wCVD) among the three myopia groups (P>0.05). The increase in mGCIPL was statistically significant in the low myopia group (P<0.01), but there was no statistically significant difference in the moderate myopia and high myopia groups (P>0.05). There was no significant difference in foveal avascular zone (FAZ) among the three myopia groups before and after medication (P>0.05). There was no correlation between CVD, AL, and SE in the three myopia groups (P>0.01). There was a low correlation between CVD and mGCIPL in the low myopia group (r=0.442, P<0.05), there was no correlation between CVD and mGCIPL in the moderate myopia and high myopia groups (P >0.01). CONCLUSION: 0.01% atropine can significantly reduce the rate of axial and refractive growth in children with low to moderate myopia, increase the density of central macular vessels, and increase the thickness of mGCIPL in children with low to moderate myopia.

BACKGROUND:Piezo1,a mechanosensitive protein,is tightly connected to osteogenic differentiation,and it has been demonstrated that TAZ has a role in regulating osteogenic differentiation.It is unclear whether TAZ participates in the regulation of osteogenic differentiation of human bone marrow mesenchymal stem cells by Piezo1,so it is crucial to investigate its unique mechanism to prevent osteonecrosis of the femoral head. OBJECTIVE:To elucidate what function Piezo1 plays in osteogenic differentiation and TAZ expression in human bone marrow mesenchymal stem cells. METHODS:The siRNA targeting Piezo1 was constructed and transfected into 293T cells.The silencing efficiency was detected by RT-qPCR.The selected Piezo1-Home-2337 was packaged according to the silencing efficiency,and its optimal multiplicity of infection value was assayed by immunofluorescence staining.The packaged Piezo1 silencing recombinant lentivirus was transfected into human bone marrow mesenchymal stem cells,and its silencing effect was detected by RT-qPCR and western blot assay.Alizarin red staining,alkaline phosphatase activity analysis,immunofluorescence staining,RT-qPCR and western blot assay were utilized to analyze the effect of silencing Piezo1 on the osteogenic differentiation of human bone marrow mesenchymal stem cells. RESULTS AND CONCLUSION:(1)The mRNA and protein levels of Piezo1 in human bone marrow mesenchymal stem cells transfected by si-Piezo1 were decreased significantly,with a statistically significant difference compared with normal and negative control groups.(2)The alkaline phosphatase activity in the si-Piezo1 group was much lower and the calcium deposition in the si-Piezo1 group was significantly reduced compared with the negative control group.(3)The mRNA levels of osteogenesis-related genes including Runt-related transcription factor 2(Runx2),osteopontin(OPN),distal-less homeobox 5(DLX5),osteocalcin,β-catenin and Tafazzin(TAZ)in the si-Piezo1 group were significantly decreased compared with the negative control group.Afterward,the expression levels of TAZ and β-catenin protein in the si-Piezo1 group were down-regulated significantly compared with the negative control group,whereas the expression levels of p-TAZ and p-β-catenin protein in the si-Piezo1 group had the opposite condition.(4)The results of immunofluorescence staining showed that the expression of TAZ and β-catenin in human bone marrow mesenchymal stem cells in the si-Piezo1 group was less compared with the negative control group.(5)These findings indicate that Piezo1 can promote the osteogenic differentiation of human bone marrow mesenchymal stem cells.The osteogenic ability of human bone marrow mesenchymal stem cells is significantly reduced after silencing Piezo1,and the expression of TAZ is also reduced.

BACKGROUND:Compound Shengmai Chenggu capsule has good therapeutic effects on early steroid-induced osteonecrosis of the femoral head,but the exact mechanism of treatment is not fully understood. OBJECTIVE:To observe the effect of compound Shengmai Chenggu capsule on fucosyltransferase 8,osteogenic gene and Wnt/β-catenin in bone tissue of rats with steroid-induced osteonecrosis of the femoral head. METHODS:Sixty Sprague-Dawley rats were randomized into blank group,model group,low-,middle-,and high-dose drug groups(n=12 per group).In the latter four groups,animal models of steroid-induced osteonecrosis of the femoral head were established by subcutaneous injection of imiquimod(once every 2 weeks,2 times in total)and gluteal muscle injection of methylprednisolone(once a week,4 times in total).The low-,middle-and high-dose drug groups were given 1.89,3.78 and 7.56 g/kg per day compound Shengmai Chenggu capsule solution by gavage respectively on the second day after the last modeling.The same amount of saline was given by gavage to the model group.Administration lasted 8 weeks.After the administration,micro-CT scan,histological staining,compression test,RT-qPCR and western blot were performed on the femoral head. RESULTS AND CONCLUSION:Micro-CT scan results showed that compared with the blank group,trabecular volume fraction,trabecular number and trabecular thickness were significantly decreased(P<0.05),while trabecular separation was increased in the model group(P<0.05).Compared with the model group,the compound Shengmai Chenggu capsule could increase trabecular volume fraction,trabecular number and trabecular thickness(P<0.05),and decrease trabecular separation(P<0.05)in a dose-dependent manner.Hematoxylin-eosin staining results showed that compared with the model group,the rate of empty bone lacunae was reduced in a dose-dependent group in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups(P<0.05).Immunohistochemical staining results showed that compared with the blank group,the protein expression of fucosyltransferase 8,Runx2 and bone morphogenetic protein 2 was reduced in the model group(P<0.05);compared with the model group,the compound Shengmai Chenggu capsule increased the protein expression of fucosyltransferase 8,Runx2 and bone morphogenetic protein 2 in a dose-dependent manner(P<0.05).Results from the compression test showed that there was a dose-dependent increase in the maximum load and elastic modulus of the femoral head in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups compared with the model group(P<0.05).RT-qPCR and western blot results showed that the mRNA and protein expressions of fucosyltransferase 8,Runx2,alkaline phosphatase,osteocalcin,osteoblast-specific transcription factor and bone morphogenetic protein 2 were decreased in the model group compared with the blank group(P<0.05);compared with the model group,there was a dose-dependent increase in the mRNA and protein expressions of the above indicators in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups compared with the model group(P<0.05).Compared with the blank group,the mRNA and protein expression of Wnt2,low-density lipoprotein receptor-related protein 5 and β-catenin were decreased(P<0.05)and the mRNA and protein expressions of glycogen synthase kinase 3β were increased(P<0.05)in the model group;compared with the model group,there was a dose-dependent increase in the mRNA and protein expressions of Wnt2,low-density lipoprotein receptor-related protein 5 and β-catenin(P<0.05)but a dose-dependent decrease in the mRNA and protein expressions of lycogen synthase kinase 3β(P<0.05)in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups.To conclude,the mechanism by which the compound Shengmai Chenggu capsule treats steroid-induced osteonecrosis of the femoral head may activate the Wnt/β-catenin signaling pathway through the up-regulation of fucosyltransferase 8,thereby promoting bone formation.

BACKGROUND:The majority of studies on developmental dysplasia of the hip focus on hip malformations,but there are few reports on the effects of acetabular dysplasia on the spine. OBJECTIVE:To investigate the compensation of spinopelvic parameters in coronal and sagittal views in patients with developmental dysplasia of the hip,and to explore the correlation between acetabular development and spinopelvic parameters. METHODS:A total of 101 patients with developmental dysplasia of the hip admitted to the Third Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2018 to June 2022 were selected as the trial group,and 114 healthy subjects were selected as the control group during the same period.The spinopelvic parameters of the subjects were measured through the full-length X-ray films of the coronal and sagittal spines:lumbar lordosis,anterior pelvic tilt,thoracolumbar kyphosis,Cobb angle,and the distance between the C7 plumb line and the center sacral vertical line,sacral slope,pelvic incidence,and thoracic kyphosis.The differences in spinopelvic parameters were compared between the two groups.In addition,the differences in spinopelvic parameters in patients with unilateral,bilateral and different Crowe classifications of developmental dysplasia of the hip were compared.Pearson correlation analysis was used to explore the correlation between Sharp angle and spinopelvic parameters. RESULTS AND CONCLUSION:(1)In the sagittal view,the lumbar lordosis in the trial group was significantly lower than that in the control group(P<0.05).The pelvic tilt and kyphosis angle of the thoracolumbar segment in the trial group were significantly greater than those in the control group(P<0.05).In the coronary position,the Cobb angle and the distance between the C7 plumb line and center sacral vertical line in the trial group were significantly greater than those in the control group(P<0.05).There was no significant difference in the remaining spinopelvic parameters between the two groups(P>0.05).(2)The lumbar lordosis of patients with bilateral developmental dysplasia of the hip was significantly lower than that of patients with unilateral developmental dysplasia of the hip(P<0.05).The pelvic tilt,thoracolumbar kyphosis,Cobb angle and the distance between the C7 plumb line and center sacral vertical line in bilateral developmental dysplasia of the hip patients were significantly greater than those in unilateral developmental dysplasia of the hip patients(P<0.05).(3)The lumbar lordosis decreased with the increase of Crowe classification severity(P<0.05).The pelvic tilt increased with the severity of the Crowe classification(P<0.05).(4)Pearson correlation analysis showed that Sharp angle was negatively correlated with lumbar lordosis(P<0.05),while Sharp angle was positively correlated with anterior pelvic tilt,Cobb angle,C7 plumb line and center sacral vertical line(P<0.05).(5)It is concluded that the pelvic tilt,thoracolumbar kyphosis,Cobb angle and the distance between the C7 plumb line and center sacral vertical line increase,while lumbar lordosis decreases in developmental dysplasia of the hip patients.The degree of acetabular dysplasia was significantly correlated with lumbar lordosis,pelvic tilt,Cobb angle,C7 plumb line and center sacral vertical line.

BACKGROUND:Periprosthetic joint infection is one of the most unwanted complications for surgeons and patients after arthroplasty,and its recalcitrance and intractability have always been a headache for arthroplasty surgeons. OBJECTIVE:To review the latest domestic and international clinical treatments used in the treatment of periprosthetic joint infection after hip and knee arthroplasty in recent years,including antibiotic treatment,surgical treatment,biological treatment and Chinese medicine treatment,to promote the research progress in the treatment of periprosthetic joint infection in China. METHODS:The literature from January 2000 to October 2022 on CNKI,WanFang,VIP,and PubMed was retrieved by the first author.762 articles were obtained by reading the titles for initial screening,then 194 articles were obtained by reading the abstracts and excluding studies with duplicate contents,low data reliability,and outdated views.Finally,88 articles were included through intensive reading of the original text. RESULTS AND CONCLUSION:(1)Combined antibiotic regimens may help eradicate the infection in the treatment of periprosthetic infections.(2)Two-stage revision remained the golden indicator for the treatment of periprosthetic infection.(3)One-stage revision lacked large-sample clinical studies and required more clinical observation.(4)Phage therapy and newer drug delivery systems in biological therapy had been applied in small amounts in the clinic,showing their advantages in the prevention and eradication of periprosthetic infections.(5)Chinese medicine with antibiotics and surgical treatment methods can improve the prevention and treatment of periprosthetic joint infection,but high-level evidence-based medical evidence was lacking.

BACKGROUND:The sclerotic zone in the femoral head is an important imaging feature in the progression of steroid-induced femoral head necrosis,which is associated with disease prognosis.Peroxisome proliferator-activated receptor γ coactivator 1α(PGC-1α)has been shown to possess biological activities such as osteogenesis,angiogenesis and anti-mitochondrial apoptosis,which may be closely related to bone repair of steroid-induced femoral head necrosis. OBJECTIVE:To screen for the differential proteins in the sclerotic zone of steroid-induced osteonecrosis of the femoral head versus the normal zone,to screen for hub proteins in the sclerotic zone,and to verify the differential expression of hub proteins in the femoral head specimens following steroid-induced femoral head necrosis,and to to explore the repair pattern of the sclerotic zone following steroid-induced femoral head necrosis. METHODS:Femoral head samples were collected from patients with steroid-induced osteonecrosis of the femoral head receiving total hip arthroplasty.The differentially expressed genes in the sclerotic zone and the normal zone were screened by Tandem Mass Tags and analyzed by GO and KEGG signaling pathways to construct a protein-protein interaction network and screen hub genes.In addition,the expression of hub genes in the sclerotic zone was verified by immunohistochemistry and western blot. RESULTS AND CONCLUSION:Quantitative protein profiling by Tandem Mass Tags revealed that 609 proteins were significantly differentially expressed(Log2FC＞1.20,Log2FC＜0.84 and P＜0.05)in the sclerotic zone of the femoral head compared with the normal zone,of which 290 proteins were upregulated and 319 proteins were downregulated.The GO and KEGG pathway enrichment analyses revealed that among the top 10 enriched pathways,Wnt signaling pathway and life-cycle regulatory pathway were closely related to bone repair;in the life-cycle regulatory pathway,PGC-1α was one of the important proteins.In addition,western blot results verified the low expression of PGC-1α and NRF1 in the sclerotic zone and high expression of Cleaved Caspase-3 in the sclerotic zone compared with the normal zone of steroid-induced femoral head necrosis specimens.Light microscopic immunohistochemical results showed the distribution of PGC-1α,NRF1 and Cleaved Caspase-3 positive expression in the sclerotic and normal zones in the femoral head tissue specimens,indicating the presence of their expression in bone trabeculae,osteoblasts and bone marrow.In contrast,the brown area of the sclerotic zone of femoral head necrosis stained darker and showed more obvious expression of Cleaved Caspase-3.To conclude,in the sclerotic zone of steroid-induced femoral head necrosis,biological behaviors including activation of osteogenesis-related pathways such as Wnt and oxidative apoptosis characterized by low expression of PGC-1 are observed.Low expression of PGC-1α in the sclerotic zone of steroid-induced femoral head necrosis may be associated with the activation of oxidative apoptosis.

BACKGROUND:The gluteus medius not only abducts the hip joint,but also plays an important role in limiting the external movement of the femoral head.At present,there is a lack of research on the correlation between gluteus medius status and non-traumatic femoral head necrosis. OBJECTIVE:To investigate the relationship between the gluteus medius width ratio and the medial space ratio of the hip joint and the progression of non-traumatic femoral head necrosis,and to explore the effect of gluteus medius atrophy on the surface and necrotic zone stress of the femoral head necrosis through finite element analysis. METHODS:Retrospective analysis of unilateral non-traumatic femoral head necrosis patients admitted to Third Affiliated Hospital of Guangzhou University of Chinese Medicine was performed.All patients were followed up for an average of more than 2 years.They were divided into a collapsed group and a non-collapsed group based on whether there was collapse of the femoral head during the follow-up.Medial space ratio,gluteus medius width ratio,Sharp angle,gluteus medius length ratio,and gluteus medius activation angle were measured and calculated.The differences in these indicators were compared between the two groups.At the first visit and follow-up at 3,6,12,and 24 months,the medial space ratio and gluteus medius width ratio were measured and calculated to explore the changes of these two indicators in the course of non-traumatic femoral head necrosis.In addition,using three-dimensional finite element analysis,a Japanese Investigation Committee classification C1 type femoral head necrosis model was constructed based on CT data.At the same time,based on MRI data,a model of the gluteus medius muscle was constructed and divided into a gluteus medius muscle atrophy group(gluteus medius width ratio:74%-76%)and a gluteus medius muscle normal group(gluteus medius width ratio:94%-96%).Each group constructed 10 models,with 6 degrees of freedom of the distal femur constrained to zero.600 N pressures were applied along the Z-axis to the upper surface of the sacrum.The stress distribution,maximum stress values on the surface and necrotic area of the femoral head,and the maximum displacement of the necrotic area were compared between two groups of models. RESULTS AND CONCLUSION:(1)A total of 153 patients(67 males and 86 females)with 153 hips were included in this study.(2)At the 24-hour follow-up,the medial space ratio of the collapsed group was significantly higher than that of the non-collapsed group(P<0.05).The gluteus medius width ratio of the collapsed group was significantly lower than that of the non-collapsed group(P<0.05).There was no statistically significant difference in Sharp angle,gluteus medius activation angle,and gluteus medius length ratio between the two groups(P>0.05).(3)Since the follow-up time exceeded 3 months,the gluteus medius width ratio of the collapsed group was lower than that of the non-collapsed group(P<0.05).Since the follow-up time exceeded 12 months,the medial space ratio of the collapsed group was higher than that of the non-collapsed group(P<0.05).(4)Pearson correlation analysis showed a significant positive correlation between follow-up time and medial space ratio in the collapsed group(P<0.05),and a significant negative correlation between follow-up time and gluteus medius width ratio(P<0.05).The regression coefficient of gluteus medius width ratio was larger than that of medial space ratio.(5)The group with middle gluteal muscle atrophy showed significant stress concentration on the surface of the femoral head,and the stress zone was significantly located on the outside.The maximum stress on the surface of the femoral head in the group with middle gluteal muscle atrophy was significantly greater than that in the group with normal middle gluteal muscle(P<0.05).There was significant stress concentration in the necrotic area of the middle gluteal muscle atrophy group,and the maximum stress was located at the edge of the necrotic area.The maximum stress and maximum displacement in the necrotic area of the middle gluteal muscle atrophy group were significantly greater than those of the normal group(P<0.05).(6)It is indicated that gluteus medius width ratio is an effective indicator for evaluating changes in gluteal muscle atrophy.In the progression of non-traumatic femoral head necrosis,atrophy of the gluteus medius muscle first occurs,followed by widening of the medial hip joint space.The mechanical mechanism may be that the atrophy of the gluteus medius muscle affects the stability of the hip joint,leading to external displacement of the femoral head,and increasing stress and displacement on the surface and necrotic area of the femoral head.

Hemophilic arthritis(HA),caused by recurrent bleeding,can seriously affect patient quality of life and consumes extensive social and medical resources.There is thus a need to establish an animal model of HA for research;however,this is limited by ethical requirements.Here we review the recent literature and summarize research progress into animal models of HA at home and abroad,from the aspects of species selection,modeling method,histopathology,and imaging evaluation method.Species selection includes rodents such as mice,New Zealand rabbits,beagles,miniature pigs,and crab-eating macaques.Modeling method comprise gene knockout trauma models,gene knockout spontaneous models,and injection models.Among these,the gene knockout spontaneous model closely mimics the pathological process of spontaneous bleeding and concurrent arthritis in human HA,making it more relevant to human HA.However,due to high modeling costs,phenotypic instability,and low survival rates,this model is not the preferred choice for animal experimental studies.In contrast,gene knockout trauma models exhibit characteristics such as short modeling time,strong stability,and high success rates,thus being widely utilized in animal experimental research.Evaluation of HA models involves various imaging method including MRI,micro-CT,MSKUS/PD,in addition to various gross scoring method.By reviewing the progress of HA model research,more experimental evidence is provided for investigating the pathogenesis and validating the efficacy of HA treatments,thereby compensating for the lack of clinical data,particularly in the field of traditional Chinese medicine therapy.