Corticosteroid-induced Osteonecrosis of the Femoral Head: Detection, Diagnosis, and Treatment in Earlier Stages

The role of the TARDBP gene in osteonecrosis of the femoral head: Bioinformatics analysis and mechanistic exploration

Osteonecrosis of the femoral head (ONFH) is a condition caused by venous stasis, impaired arterial blood flow, or destruction of the femoral head, often resulting in the localized death of bone cells and bone marrow components, leading to joint collapse. Although the pathogenesis of ONFH is complex, recent attention has focused on the role of the TAR DNA-binding protein (TARDBP) gene and its encoded protein, TDP-43, in the disease process. TDP-43, which plays a role in neurodegenerative diseases, may also regulate apoptosis, oxidative stress, and immune responses in ONFH. This study utilized the GSE74089 and GSE123568 datasets from the gene expression omnibus database to analyze differentially expressed genes between ONFH and normal samples. Through batch effect correction, gene enrichment analysis (gene ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment analysis), protein-protein interaction network construction, and weighted gene co-expression network analysis, key genes in ONFH were identified. Additionally, immune infiltration was analyzed using CIBERSORT, and a neural network model was developed to assess the importance of these genes in ONFH. The analysis revealed that TARDBP expression was significantly elevated in ONFH samples and correlated with the infiltration of monocytes and M1 macrophages. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses suggested that TARDBP may regulate bone metabolism and repair via the Wnt/β-catenin signaling pathway. Protein-protein interaction network analysis identified 9 core genes, with TARDBP scoring the highest in the neural network model, indicating its pivotal role in ONFH regulation. TARDBP is highly expressed in ONFH, and its possible role by regulating apoptosis, oxidative stress, and immune response provide new ideas for the study of the molecular mechanism of ONFH.

Utilizing bioinformatics to identify biomarkers and analyze their expression in relation to immune cell ratios in femoral head necrosis

Background

Necrosis of the Femoral Head (NFH) represents a challenging orthopedic condition, characterized by elusive early detection and rapid progression, predominantly in the middle-aged demographic. Current research on the pathophysiological and immunoregulatory mechanisms underpinning immune cell infiltration in NFH is sparse. This study employs bioinformatics analysis of publicly available RNA sequencing databases to elucidate the pivotal molecules and pathways implicated in NFH progression.

Methods

The NFH-related dataset GSE123568 was obtained from the Gene Expression Omnibus (GEO). Subsequently, CIBERSORT was utilized to assess the proportion and distribution of immune cell types, followed by the identification of critical Hub immune cells using LASSO and RFE algorithms. The dataset GSE123568 was then explored to identify significantly differentially expressed genes (DEGs). These genes were further refined by intersecting with death-associated genes reported in existing literature. GO and KEGG pathway enrichment analyses were conducted to elucidate their underlying molecular mechanism. A protein-protein interaction (PPI) network was constructed using the STRING database and visualized via Cytoscape. Hub genes were identified using the CytoHubba plugin, followed by enrichment analysis, and their expression levels were evaluated using the ROC curve. In addition, we performed expression data visualization and ROC curve analysis on the external dataset GSE74089 to further evaluate the discriminative power of the hub genes. Moreover, the study analyzed the correlation between the identified hub genes and Hub immune cells. Finally, we verified the hub genes utilizing real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry.

Results

Four types of immune cells (Neutrophil, Mast cell resting, Myeloid dendritic cell activated, Macrophage M0) were identified. Fourteen pivotal genes (BCL2L1, BIRC2, NFKBIA, XIAP, CFLAR, AKT1, BIRC3, IKBKB, RIPK1, CASP8, TNFRSF1A, IL1B, CASP1, STAT3) were identified, and the findings were validated using the external dataset GSE74089. Among these, STAT3 exhibited the most pronounced positive correlation with neutrophils (r = 0.6804, p = 3.525e-05). Conversely, XIAP displayed the most significant negative correlation with Myeloid dendritic cell activated (r = -0.3610, p = 0.04003). In experiments, the experimental outcomes for five hub genes (CASP8, TNFRSF1A, AKT1, XIAP and STAT3) were congruent with the results obtained from bioinformatics analysis.

Conclusion

Our study identified CASP8, TNFRSF1A, AKT1, XIAP, STAT3 and BCL2L1 as potential biomarkers for NFH patients and elucidated the immune cell types with the strongest association to these markers. These insights may be crucial for the early diagnosis, understanding of the pathophysiological mechanisms, and the development of treatment strategies for NFH.

Core decompression, allogenic fibula fixation, and pedicled fibula grafting are effective for osteonecrosis of femoral head

OBJECTIVE

To explore the application effects of core decompression, allograft fibula fixation, and pedicled fibula grafting in osteonecrosis of the femoral head (ONFH).

METHODS

Forty patients with ONFH admitted to Ziyang Central Hospital from March 2017 to March 2022 were included in this study. According to the Association Research Circulation Osseous (ARCO) staging criteria, 20 patients at stage I underwent core decompression, 8 patients at stage II underwent core decompression combined with allogenic fibula fixation, and 12 patients at stage III underwent core decompression combined with pedicled fibula grafting.

RESULTS

After 1 year of follow-up, changes in hip joint function (Harris score) and pain level (visual analogue scale (VAS)) were compared before and after surgery. Imaging examination results were recorded, and efficacy and ARCO stage progression were compared with preoperative findings. All 40 patients received follow-up for 1 year. The results showed that the Harris score at 1 year post-operation was higher than pre-operation, while the VAS score was lower (P<0.05). Hip joint function evaluation in the 20 patients at stage I showed excellent, good, and fair results in 12 (60.00%), 5 (25.00%), and 3 (15.00%) cases, respectively, with X-ray examination indicating complete stability and no progression in ARCO staging. Among the 8 patients at stage II, hip joint function evaluation showed excellent, good, fair, and poor results in 4 (50.00%), 2 (25.00%), 1 (12.50%), and 1 (12.50%) cases, respectively. X-ray examination revealed stability in 7 cases, while 1 case progressed to ARCO stage IV and ultimately required artificial hip arthroplasty. Among the 12 patients at stage III, hip joint function evaluation revealed excellent, good, fair, and poor results in 5 (41.67%), 3 (25.00%), 2 (16.67%), and 2 (16.67%) cases, respectively. X-ray examination indicated stability in 10 cases, while 2 cases progressed to ARCO stage IV and ultimately required artificial hip arthroplasty.

CONCLUSION

Patients with stage I, II, and III ONFH achieved good short-term therapeutic outcomes using core decompression, core decompression with allogenic fibula fixation, and core decompression with pedicled fibula grafting. These methods effectively improved hip joint function and alleviated pain symptoms. Hence, it is crucial to select appropriate surgical methods based on the specific conditions of patients in clinical practice.

A new mechanism in steroid-induced osteonecrosis of the femoral head and the protective role of simvastatin

OBJECTIVE

Steroid-induced osteonecrosis of the femoral head (SONFH) is a debilitating bone condition associated with femoral head collapse and hip joint dysfunction. The pathogenesis of SONFH is still not fully elucidated. This study aims to explore the role of mitochondrial cardiolipin metabolism disruption in SONFH and the potential protective effects of simvastatin (SIM).

METHODS

Osteoblasts were cultured in vitro under high concentrations of dexamethasone (DEX) to mimic the effects of glucocorticoid exposure seen in SONFH. Mitochondrial structural changes and cardiolipin distribution were examined using transmission electron microscopy and confocal microscopy. Osteoblast proliferation and apoptosis were assessed using CCK-8 assays and flow cytometry. Mitochondrial cardiolipin content was quantified by ELISA, while cytochrome c (Cyt-c) expression was measured through Western blotting. Mitochondrial staining with NAO was analyzed using confocal microscopy and flow cytometry.

RESULTS

DEX exposure led to mitochondrial cardiolipin metabolism disorder and redistribution, resulting in significant mitochondrial structural damage. This disruption was associated with increased release of Cyt-c into the cytoplasm, which correlated with heightened osteoblast apoptosis. SIM treatment mitigated these effects, reducing osteoblast apoptosis by preserving mitochondrial function and modulating cardiolipin content and distribution.

CONCLUSION

This study demonstrates, for the first time, that glucocorticoid-induced disruptions in mitochondrial cardiolipin metabolism contribute to the pathogenesis of SONFH by inducing Cyt-c release and subsequent osteoblast apoptosis. SIM exerts a protective effect by preserving mitochondrial integrity and function, offering a potential therapeutic avenue for treating hormone-induced osteoblast damage in SONFH.

Osteonecrosis as a manifestation of Long-COVID Syndrome: a systematic review

Purpose SARS-CoV-2 is an RNA virus responsible for COVID-19 pandemic. Some authors described the set of persistent symptoms COVID-related as "Long-COVID Syndrome." Several cases of post-COVID-19 osteonecrosis (ON) are described. Our primary aim was to study the hypothetical correlation between SARS-CoV-2 infection and ON; our secondary aim was to understand if ON can be considered part of Long-COVID. Materials and methods We performed a systematic review following the Preferred Reporting Items for Systematic Reviewers and Meta-analysis (PRISMA) guidelines. Because COVID-19 is a recently described disease, we included all levels of evidence studies. We excluded studies lacking specification regarding the use of corticosteroids (CCS) and studies not related to COVID-19. The variables extracted were age, sex, risk factors, affected joints, signs and symptoms, magnetic resonance imaging (MRI) and X-ray features, histology, treatment of COVID-19, dose and duration of treatment with CCS, treatment of ON, follow-up, and treatment outcome. Results A total of 13 studies were included, involving 95 patients and 159 joints. Time between the diagnosis of COVID-19 and the onset of symptoms related to ON was 16 weeks on average. Time between the onset of symptoms and the MRI was 6 weeks. An average of 926.4 mg of prednisolone equivalent per patient were administered. On average, CCS were administered for 20.6 days. Conclusions Patients with a history of COVID-19 infection developed osteonecrosis prematurely and with a lower dose of CCS than usually reported in the literature. Symptoms of osteonecrosis occur within the interval of the period described as Long-COVID. Surgeons should not underestimate the persistence of arthralgia when a history of SARS-CoV-2 infection and use of CCS is reported.

Risk factors for steroid-induced osteonecrosis of the femoral head in children with immune kidney disease

Objective

To investigate the risk factors for steroid-induced osteonecrosis of the femoral head (SONFH) after glucocorticoid (GC) therapy in children with immune kidney diseases.

Methods

This retrospective study included patients (1-18 years) diagnosed with immune kidney disease treated with GCs from January 2012 to July 2022 in our hospital. Data, such as sex, age and body weight at the first GC treatment, and the GC dose, were collected. Patients were divided into SONFH and non-SONFH groups based on the occurrence of SONFH. According to the International Classification of Diseases, Tenth Revision, the disease diagnosis was searched on the clinical data webpage of our hospital. The descriptive statistics and binary logistic regression analyses were performed. A nomogram was constructed to predict the risk of SONFH in children with immune kidney disease after GC treatment. The predictive ability of the nomogram was evaluated using the concordance index and calibration plots.

Results

The SONFH and non-SONFH groups included 18 and 90 patients, respectively. Age at first GC treatment, 6-month cumulative [oral (po) plus intravenous (iv)] GC dose, total cumulative prednisone (po) dose, total cumulative methylprednisolone (iv) dose for pulse therapy and total cumulative GC (po plus iv) dose significantly differed between the two groups. Age at the initial GC treatment, total cumulative prednisone (po) dose and total cumulative methylprednisolone (iv) dose for pulse therapy were independent risk factors for SONFH in the multivariate analysis.

Conclusions

This study identified specific risk factors for developing SONFH during GC treatment. Thus, children with immune kidney disease undergoing GC treatment should be monitored closely based on these risk factors, with the aim to avoid irreversible damage to the femoral head.

Development and evaluation of a 3D ensemble framework for automatic diagnosis of early osteonecrosis of the femoral head based on MRI: a multicenter diagnostic study

Background

Efficient and reliable diagnosis of early osteonecrosis of the femoral head (ONFH) based on MRI is crucial for the formulation of clinical treatment plans. This study aimed to apply artificial intelligence (AI) to achieve automatic diagnosis and visualization of early ONFH, thereby improving the success rate of hip-preserving treatments.

Method

This retrospective study constructed a multicenter dataset using MRI data of 381 femoral heads from 209 patients with ONFH collected from four institutions (including 239 early ONFH cases and 142 non-ONFH cases). The dataset was divided into training, validation, and internal and external test datasets. This study developed a 3D ensemble framework to automatically diagnose early osteonecrosis of the femoral head based on MRI and utilized 3D Grad-CAM to visualize its decision-making process. Finally, the diagnostic performance of the framework was experimentally evaluated on the MRI dataset and compared with the diagnostic results of three orthopedic surgeons.

Results

On the internal test dataset, the 3D-ONFHNet framework achieved overall diagnostic performance with an accuracy of 93.83%, sensitivity of 89.44%, specificity of 95.56%, F1-score of 87.67%, and AUC of 95.41%. On the two external test datasets, the framework achieved overall diagnostic accuracies of 87.76% and 87.60%, respectively. Compared to three orthopedic surgeons, the diagnostic performance of the 3D-ONFHNet framework was comparable to that of senior orthopedic surgeons and superior to that of junior orthopedic surgeons.

Conclusions

The framework proposed in this study can generate staging results for early ONFH and provide visualizations of internal signal changes within the femoral head. It assists orthopedic surgeons in screening for early ONFH on MRI in a clinical setting, facilitating preoperative planning and subsequent treatment strategies. This framework not only enhances diagnostic efficiency but also offers valuable diagnostic references for physicians.

Polydopamine grafting polyether ether ketone to stabilize growth factor for efficient osteonecrosis repair

This study examines the biocompatibility, osteogenic potential, and effectiveness of polyether ether ketone (PEEK) composites for treating osteonecrosis, seeking to establish a theoretical basis for clinical application. A range of PEEK composite materials, including sulfonated polyether ether ketone (SPEEK), polydopamine-sulfonated polyether ether ketone (SPEEK-PDA), bone-forming peptide-poly-dopamine-sulfonated polyether ether ketone (SPEEK-PDA-BFP), and vascular endothelial growth factor-poly-dopamine-sulfonated polyether ether ketone (SPEEK-PDA-VEGF), were constructed by concentrated sulfuric acid sulfonation, polydopamine modification and grafting of bioactive factors. The experiments involved adult male New Zealand rabbits aged 24-28 weeks and weighing 2.6-4 kg. The SPEEK-PDA-BFP possesses the smallest water contact angle, indicating the highest hydrophilicity, with its surface characterized by a rich density of clustered BFP particles. The SPEEK-PDA-BFP exhibits superior adhesion, proliferation, and differentiation capabilities, along with pronounced bacteriostatic effects, which are attributed to its dense particle clusters. The SPEEK-PDA-BFP facilitates the formation of regular and dense bone trabeculae. Comparative study on treating osteonecrosis with SPEEK-PDA-VEGF and SPEEK-PDA-BFP highlighted the superior formation of mature bone trabeculae and angiogenic protein CD31 around SPEEK-PDA-VEGF. The PEEK composite materials have good biocompatibility, osteogenic activity and bone repair activity. In particular, SPEEK-PDA-VEGF composite materials have the best effect on bone repair.

USP13 overexpression in BMSCs enhances anti-apoptotic ability and guards against methylprednisolone-induced osteonecrosis in rats

Methylprednisolone (MPS) use is linked to increased cases of osteonecrosis of the femoral head (ONFH). Bone marrow mesenchymal stem cells (BMSCs) have shown potential for treating MPS-induced ONFH, but their effectiveness is limited by high apoptosis rates post-transplantation. We developed a pretreatment strategy for BMSCs to improve their viability. In a rat model of MPS-induced ONFH, we evaluated the effects of USP13 overexpression in BMSCs through micro-CT, HE staining, and TUNEL staining. USP13-overexpressing BMSCs significantly reduced ONFH severity compared to plain BMSCs and direct lentivirus injection. USP13 also protected BMSCs from MPS-induced apoptosis by modulating PTEN and reducing AKT phosphorylation. This led to decreased expression of apoptotic genes and proteins in USP13-overexpressing BMSCs. Our findings highlight USP13 as a promising target for enhancing BMSC survival and efficacy in treating MPS-induced ONFH.

Asymptomatic multifocal avascular necrosis, a commonly overlooked finding in patients with systemic lupus erythematosus

BACKGROUND

In patients with Systemic lupus erythematosus (SLE), osteonecrosis of various joints is a debilitating complication associated with the disease and its treatment, in which a considerable proportion of osteonecrosis may be asymptomatic. Recognizing the crucial role of early and timely detection, as well as appropriate management of asymptomatic osteonecrosis, in preventing joint destruction, we conducted a study to evaluate the prevalence of asymptomatic osteonecrosis in SLE patients who have already been diagnosed with symptomatic osteonecrosis. Additionally, we aimed to examine the relationship between proposed risk factors of osteonecrosis and the development of asymptomatic osteonecrosis.

METHODS

In this cross-sectional study, Patients with recently diagnosed symptomatic osteonecrosis of at least one joint were selected by reviewing data from the digital medical record system of the Rheumatology Research Center. The patients underwent three-phase Single Photon Emission Computed Tomography (SPECT) bone scintigraphy to screen for other asymptomatic osteonecrotic joints. MRI was subsequently performed on the asymptomatic osteonecrotic sites for further diagnostic confirmation. The study evaluated the prevalence of asymptomatic osteonecrosis, the extent of joint involvement, the specific locations of osteonecrosis, the most commonly affected joints, and the risk factors for asymptomatic osteonecrosis.

RESULTS

Eight out of the 17 patients (47%) who participated in our research were found to have asymptomatic osteonecrosis. The most commonly affected joint without symptoms was the left knee (25%), while the most frequently affected joint with symptoms was the left hip (23.07%). The only statistically significant difference observed between patients with and without asymptomatic osteonecrosis in this study was the age at which the disease first appeared (p = 0.046) and this age was higher among patients with asymptomatic osteonecrosis.

CONCLUSIONS

Our research provides further evidence of the high incidence of asymptomatic osteonecrosis in individuals with SLE due to the nature of the disease and the frequent use of high-dose corticosteroids. It underscores the importance of early detection through whole-body SPECT bone scintigraphy and MRI, as well as prompt intervention in order to avert the incapacitating effects of osteonecrosis.

Translational horizons in stem cell therapy for osteonecrosis of the femoral head: a journey from basic research to clinical practice through bibliometric insights

BACKGROUND

Osteonecrosis of the femoral head (ONFH) significantly impacts young and middle-aged adults, with steroid use implicated in many cases. Traditional treatments have limited efficacy, prompting a shift towards innovative approaches, such as stem cell therapy, offering less invasive regenerative solutions.

METHODS

Using bibliometric analysis from 1997 to 2023, we identified 392 articles on stem cell therapy for ONFH from the Web of Science Core Collection and analysed them using VOSviewer and CiteSpace to identify key trends and research directions.

RESULTS

From 1997 to 2023, stem cell therapy for ONFH research expanded significantly, with 392 articles evidencing global collaboration, particularly from China, the United States and South Korea. The field is characterised by 158 core authors across 26 clusters and contributions from 417 institutions in 104 research clusters, with Shanghai Jiao Tong University as a notable leader. This research is disseminated through 23 journal clusters, emphasising interdisciplinary work, with Clinical Orthopaedics and Related Research among the most influential journals. Key findings include the identification of the most influential papers, highlighting advances, such as use of autologous mesenchymal stem cells (MSCs) and innovative delivery mechanisms. High-frequency keyword analysis further mapped the evolution of the field, from basic mechanisms to advanced therapies, underscoring a trend towards more targeted stem cell treatments for ONFH.

CONCLUSION

Stem cell therapy for ONFH has advanced significantly, showcasing a successful transition from basic research to clinical practice, particularly highlighted by developments in use of autologous MSCs and delivery methods. Future research will focus on refining therapies through exosome technology, targeted modulation of stress and inflammation and integration with surgical techniques, with the aim of tailored patient care and improved ONFH outcomes.

Combination of neuromuscular electrical stimulation and ibuprofen to reduce pain in femoral head necrosis

OBJECTIVE

The combinative effects of neuromuscular electrical stimulation and ibuprofen on pain in patients with femoral head necrosis were discussed and analyzed.

METHOD

This retrospective study analyzed data of 60 patients with femoral head necrosis hospitalized during Oct. 2020 to Oct. 2021. According to different treatment methods, the patients were divided into an observation group and a control group (30 cases in each group). The control group took oral ibuprofen sustained-release capsules, and the observation group was treated with neuromuscular electrical stimulation in addition to ibuprofen. Both groups received a 4-week treatment course. The therapeutic efficacy, Harris scale scores, Visual Analogue Scale (VAS) score, MRI hip imaging stage, SF-36 scale score, serum plasminogen activator inhibitor 1 (PAI-1), leptin and osteopontin levels before and after treatment were compared between the two groups.

RESULTS

After treatment, the overall response rate in the observation group was higher than that in control group (P<0.05). The post-treatment scores of Harris scale were higher in both groups than those pre-treatment (P<0.05), and were higher in the observation group than in the control group (P<0.05). The VAS scores were decreased in both groups (P<0.05), and the decrease was more significant in the observation group than in the control group (P<0.05). After treatment, there were more patients with 0-I MRI hip imaging stage in the two groups than before treatment (P<0.05), and more in the observation group than in the control group (P<0.05). The SF-36 scores in both groups were increased (P<0.05), and the increase was more significant in the observation group than in the control group (P<0.05). The serum levels of PAI-1, leptin and osteopontin were decreased in both groups (P<0.05), and the decreases were more significant in the observation group than in the control group (P<0.05).

CONCLUSION

The combinative treatment of neuromuscular electrical stimulation and ibuprofen has a significant effect on patients with femoral head necrosis. The treatment can remarkably reduce patients' pain, improve their hip function and quality of life, and decrease the PAI-1, leptin and osteopontin levels.

Crebanine mitigates glucocorticoid-induced osteonecrosis of the femoral head by restoring bone remodelling homeostasis via attenuating oxidative stress

The onset of osteonecrosis of the femoral head (ONFH) is intimately associated with the extensive administration of glucocorticoids (GCs). Long-term stimulation of GCs can induce oxidative stress in both osteoclasts (OCs) and osteoblasts (OBs), resulting in the disturbance of bone remodelling. An alkaloid named crebanine (CN) demonstrates pharmacological properties including anti-inflammation and reactive oxygen species (ROS) modulation. Our objective is to assess the therapeutic potential of CN in treating ONFH and elucidate the associated underlying mechanisms. The network pharmacology analysis uncovered that CN played a role in regulating ROS metabolism. In vitro, CN demonstrated its ability to reduce the dexamethasone (DEX)-stimulated generation of OCs and suppress their resorptive function by downregulating the level of osteoclast marker genes. Concurrently, CN also mitigated DEX-induced damage to OBs, facilitating the restoration of osteoblast marker gene expression, cellular differentiation and function. These effects were achieved by CN augmenting the antioxidant system to reduce intracellular ROS levels. Furthermore, in vitro results were corroborated by micro-CT and histological data, which also showed that CN attenuated MPS-induced ONFH in mice. This study highlights the therapeutic potential of CN in counteracting GCs-induced ONFH.

Panoramic heat map for spatial distribution of necrotic lesions

Aims

In this study, we aimed to visualize the spatial distribution characteristics of femoral head necrosis using a novel measurement method.

Methods

We retrospectively collected CT imaging data of 108 hips with non-traumatic osteonecrosis of the femoral head from 76 consecutive patients (mean age 34.3 years (SD 8.1), 56.58% male (n = 43)) in two clinical centres. The femoral head was divided into 288 standard units (based on the orientation of units within the femoral head, designated as N[Superior], S[Inferior], E[Anterior], and W[Posterior]) using a new measurement system called the longitude and latitude division system (LLDS). A computer-aided design (CAD) measurement tool was also developed to visualize the measurement of the spatial location of necrotic lesions in CT images. Two orthopaedic surgeons independently performed measurements, and the results were used to draw 2D and 3D heat maps of spatial distribution of necrotic lesions in the femoral head, and for statistical analysis.

Results

The results showed that the LLDS has high inter-rater reliability. As illustrated by the heat map, the distribution of Japanese Investigation Committee (JIC) classification type C necrotic lesions exhibited clustering characteristics, with the lesions being concentrated in the northern and eastern regions, forming a hot zone (90% probability) centred on the N4-N6E2, N3-N6E units of outer ring blocks. Statistical results showed that the distribution difference between type C2 and type C1 was most significant in the E1 and E2 units and, combined with the heat map, indicated that the spatial distribution differences at N3-N6E1 and N1-N3E2 units are crucial in understanding type C1 and C2 necrotic lesions.

Conclusion

The LLDS can be used to accurately measure the spatial location of necrotic lesions and display their distribution characteristics.

Identifying the causal relationship between immune factors and osteonecrosis: a two-sample Mendelian randomization study

A wealth of evidence intimates a profound connection between the immune system and osteonecrosis, albeit the specific immune factors underlying this connection remain largely veiled. A bidirectional Mendelian randomization (MR) study was conducted based on genome-wide association study summary data to identify causal links between 731 immune factors and osteonecrosis including drug-induced osteonecrosis. Preliminary MR analysis was accomplished utilizing the inverse-variance weighted method under a multiplicative random effects model, and heterogeneity and potential horizontal pleiotropy were evaluated through Cochrane's Q-test, MR-Egger intercept test, MR-PRESSO global test, and leave-one-out analysis. Upon false discovery rate correction, the gene-predicted level of one immune factor (CD62L - monocyte %monocyte) exhibited a significant positive correlation with osteonecrosis, while eight immune traits associated with monocytes, dendritic cells, and NK cells demonstrated significant causal effects with drug-induced osteonecrosis. Reverse MR revealed no significant correlations. This MR research provides genetic evidence for the causal associations between a broad spectrum of immune factors and osteonecrosis. Such a study aids in unraveling the intricate interaction patterns between the immune and skeletal systems, elucidating the pathogenesis of osteonecrosis, and identifying potential novel therapeutic approaches.

Non-traumatic osteonecrosis of the femoral head induced by steroid and alcohol exposure is associated with intestinal flora alterations and metabolomic profiles

OBJECTIVE

Osteonecrosis of the femoral head (ONFH) is a severe disease that primarily affects the middle-aged population, imposing a significant economic and social burden. Recent research has linked the progression of non-traumatic osteonecrosis of the femoral head (NONFH) to the composition of the gut microbiota. Steroids and alcohol are considered major contributing factors. However, the relationship between NONFH caused by two etiologies and the microbiota remains unclear. In this study, we examined the gut microbiota and fecal metabolic phenotypes of two groups of patients, and analyzed potential differences in the pathogenic mechanisms from both the microbial and metabolic perspectives.

METHODS

Utilizing fecal samples from 68 NONFH patients (32 steroid-induced, 36 alcohol-induced), high-throughput 16 S rDNA sequencing and liquid chromatography with tandem mass spectrometry (LC-MS/MS) metabolomics analyses were conducted. Univariate and multivariate analyses were applied to the omics data, employing linear discriminant analysis effect size to identify potential biomarkers. Additionally, functional annotation of differential metabolites and associated pathways was performed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Subsequently, Spearman correlation analysis was employed to assess the potential correlations between differential gut microbiota and metabolites.

RESULTS

High-throughput 16 S rDNA sequencing revealed significant gut microbial differences. At the genus level, the alcohol group had higher Lactobacillus and Roseburia, while the steroid group had more Megasphaera and Akkermansia. LC-MS/MS metabolomic analysis indicates significant differences in fecal metabolites between steroid- and alcohol-induced ONFH patients. Alcohol-induced ONFH (AONFH) showed elevated levels of L-Lysine and Oxoglutaric acid, while steroid-induced ONFH(SONFH) had increased Gluconic acid and Phosphoric acid. KEGG annotation revealed 10 pathways with metabolite differences between AONFH and SONFH patients. Correlation analysis revealed the association between differential gut flora and differential metabolites.

CONCLUSIONS

Our results suggest that hormones and alcohol can induce changes in the gut microbiota, leading to alterations in fecal metabolites. These changes, driven by different pathways, contribute to the progression of the disease. The study opens new research directions for understanding the pathogenic mechanisms of hormone- or alcohol-induced NONFH, suggesting that differentiated preventive and therapeutic approaches may be needed for NONFH caused by different triggers.

Steroid-Induced Avascular Necrosis in the Foot and Ankle-Pathophysiology, Surgical, and Nonsurgical Therapies: Case Study and Literature Review

Steroid-induced avascular necrosis (AVN) of the lower extremity is a destructive process of the bone found in patients who have been treated with these medications for a variety of medical conditions. There are several proposed etiologies for development of this condition, however much debate still remains for the exact pathophysiology. The main clinical characteristics include edema, arthralgias, and restricted joint range of motion. Diagnostic imaging is a key aspect in the analysis of this pathologic process. When steroid-induced AVN affects multiple bones, this atypical presentation is difficult to treat due to its diffuse nature, therefore surgical options are limited. In these cases, conservative therapy is targeted toward pain relief and preserving joint range of motion. This review aims to provide an overview on the presentation of steroid-induced AVN in the foot and ankle, outline the pathophysiology of the process, and describe a variety of both conservative and surgical treatment options. A case study is provided to showcase a patient presentation of diffuse steroid-induced AVN of the foot and ankle and their course of treatment.Levels of Evidence: Level V: Expert opinion.

Glucocorticoids promote steroid-induced osteonecrosis of the femoral head by down-regulating serum alpha-2-macroglobulin to induce oxidative stress and facilitate SIRT2-mediated BMP2 deacetylation

Our study investigated the possible molecular mechanism of glucocorticoid in steroid-induced osteonecrosis of the femoral head (SINFH) through regulating serum alpha-2-macroglobulin and SIRT2-mediated BMP2 deacetylation. Essential genes involved in glucocorticoid-induced SINFH were screened by transcriptome sequencing and analyzed by bioinformatics, followed by identifying downstream regulatory targets. Rat bone marrow mesenchymal stem cells were isolated and treated with methylprednisolone (MP) for in vitro cell experiments. Besides, a glucocorticoid-induced rat ONFH was established using the treatment of MP and LPS. ChIP-PCR detected the enrichment of SIRT2 in the promoter region of BMP2, and the deacetylation modification of SIRT2 on BMP2 was determined. Bioinformatics analysis revealed that glucocorticoids may induce ONFH through the SIRT2/BMP2 axis. In vitro cell experiments showed that glucocorticoids up-regulated SIRT2 expression in BMSCs by inducing oxidative stress, thereby promoting cell apoptosis. The up-regulation of SIRT2 expression may be due to the decreased ability of α2 macroglobulin to inhibit oxidative stress, and the addition of NOX protein inhibitor DPI could significantly inhibit SIRT2 expression. SIRT2 could promote histone deacetylation of the BMP2 promoter and inhibit its expression. In vitro cell experiments further indicated that knocking down SIRT2 could protect BMSC from oxidative stress and cell apoptosis induced by glucocorticoids by promoting BMP2 expression. In addition, animal experiments conducted also demonstrated that the knockdown of SIRT2 could improve glucocorticoid-induced ONFH through up-regulating BMP2 expression. Glucocorticoids could induce oxidative stress by down-regulating serum α2M to promote SIRT2-mediated BMP2 deacetylation, leading to ONFH.

No evidence of genetic causality between diabetes and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis

OBJECTIVE

This study aimed to examine whether diabetes mellitus is causally associated with osteonecrosis.

METHOD

Using publicly accessible genome-wide association study statistics, a bidirectional two-sample Mendelian randomization analysis was carried out. In order to determine whether diabetes has a causal effect on osteonecrosis and whether osteonecrosis has a causal effect on diabetes, we extracted six date on diabetes in Europeans from IEU OpenGWAS and GWAS Catalogue and osteonecrosis in Europeans from FinnGen. We then evaluated the data using inverse variance weighting, MR-Egger regression, weighted median, weighted mode, and simple mode. The results' stability and dependability were then evaluated using sensitivity analysis and heterogeneity analysis. Finally, meta-analysis is used to further confirm if there is a relationship between diabetes and osteonecrosis.

RESULTS

When diabetes was used as an exposure factor, MR-Egger regression showed that directional fold product was unlikely to bias the results. Cochran's Q test showed only minor heterogeneity in a few data sets. Multidirectional tests Egger-intercept, MR-PRESSO and funnel plots for most data did not show multidirectional and asymmetry at the gene level. Most of the IVW results showed no causal relationship between diabetes mellitus and osteonecrosis. The results of meta-analysis of IVW methods further confirmed the absence of a causal relationship. Inverse MR analysis also showed no causal relationship between osteonecrosis and diabetes.

CONCLUSION

Results of bidirectional MR analysis show no evidence of causal relationship between diabetes and osteonecrosis.

Erythropoietin suppresses osteoblast apoptosis and ameliorates steroid-induced necrosis of the femoral head in rats by inhibition of STAT1-caspase 3 signaling pathway

BACKGROUND

Steroid-induced avascular necrosis of the femoral head (SANFH) is characterized by osteoblast apoptosis, leading to a loss of bone structure and impaired hip joint function. It has been demonstrated that erythropoietin (EPO) performs a number of biological roles.

OBJECTIVE

We examined the effects of EPO on SANFH and its regulation of the STAT1-caspase 3 signaling pathway.

METHOD

In vitro, osteoblasts were treated with dexamethasone (Dex) or EPO. We identified the cytotoxicity of EPO by CCK-8, the protein expression of P-STAT1, cleaved-caspase9, cleaved-caspase3, Bcl-2, BAX, and cytochrome c by Western blotting, and evaluated the apoptosis of osteoblasts by flow cytometry. In vivo, we analyzed the protective effect of EPO against SANFH by hematoxylin and eosin (H&E), Immunohistochemical staining, and Micro-computed tomography (CT).

RESULTS

In vitro, EPO had no apparent toxic effect on osteoblasts. In Dex-stimulated cells, EPO therapy lowered the protein expression of BAX, cytochrome c, p-STAT1, cleaved-caspase9, and cleaved-caspase3 while increasing the expression of Bcl-2. EPO can alleviate the apoptosis induced by Dex. In vivo, EPO can lower the percentage of empty bone lacunae in SANFH rats.

CONCLUSION

The present study shows that EPO conferred beneficial effects in rats with SANFH by inhibiting STAT1-caspase 3 signaling, suggesting that EPO may be developed as a treatment for SANFH.

Musculoskeletal Biomaterials: Stimulated and Synergized with Low Intensity Pulsed Ultrasound

Clinical biophysical stimulating strategies, which have significant effects on improving the function of organs or treating diseases by causing the salutary response of body, have shown many advantages, such as non-invasiveness, few side effects, and controllable treatment process. As a critical technique for stimulation, the low intensity pulsed ultrasound (LIPUS) has been explored in regulating osteogenesis, which has presented great promise in bone repair by delivering a combined effect with biomaterials. This review summarizes the musculoskeletal biomaterials that can be synergized with LIPUS for enhanced biomedical application, including bone regeneration, spinal fusion, osteonecrosis/osteolysis, cartilage repair, and nerve regeneration. Different types of biomaterials are categorized for summary and evaluation. In each subtype, the verified biological mechanisms are listed in a table or graphs to prove how LIPUS was effective in improving musculoskeletal tissue regeneration. Meanwhile, the acoustic excitation parameters of LIPUS that were promising to be effective for further musculoskeletal tissue engineering are discussed, as well as their limitations and some perspectives for future research. Overall, coupled with biomimetic scaffolds and platforms, LIPUS may be a powerful therapeutic approach to accelerate musculoskeletal tissue repair and even in other regenerative medicine applications.

Effects of Puerarin-Loaded Tetrahedral Framework Nucleic Acids on Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) is recognized as a common refractory orthopedic disease that causes severe pain and poor quality of life in patients. Puerarin (Pue), a natural isoflavone glycoside, can promote osteogenesis and inhibit apoptosis of bone mesenchymal stem cells (BMSCs), demonstrating its great potential in the treatment of osteonecrosis. However, its low aqueous solubility, fast degradation in vivo, and inadequate bioavailability, limit its clinical application and therapeutic efficacy. Tetrahedral framework nucleic acids (tFNAs) are promising novel DNA nanomaterials in drug delivery. In this study, tFNAs as Pue carriers is used and synthesized a tFNA/Pue complex (TPC) that exhibited better stability, biocompatibility, and tissue utilization than free Pue. A dexamethasone (DEX)-treated BMSC model in vitro and a methylprednisolone (MPS)-induced ONFH model in vivo is also established, to explore the regulatory effects of TPC on osteogenesis and apoptosis of BMSCs. This findings showed that TPC can restore osteogenesis dysfunction and attenuated BMSC apoptosis induced by high-dose glucocorticoids (GCs) through the hedgehog and Akt/Bcl-2 pathways, contributing to the prevention of GC-induced ONFH in rats. Thus, TPC is a promising drug for the treatment of ONFH and other osteogenesis-related diseases.

Low miR-182-5p Expressing Extracellular Vesicles Derived From Human Bone Marrow Stromal Cells of Subjects With Steroid-Induced Osteonecrosis of the Femoral Head Aggravate Disease Progression

Steroid-induced osteonecrosis of the femoral head (SONFH) is a refractory, progressive disease. However, the underlying mechanisms that aggravate femoral head necrosis remain unclear. Extracellular vesicles (EVs) act as molecular carriers in intercellular communication. We hypothesize that EVs derived from human (h) bone marrow stromal cells (BMSC) resident in SONFH lesion areas promote the pathogenesis of SONFH. In the present study, we determined the modulatory effects of SONFH-hBMSCs-derived EVs on the pathogenesis of SONFH in vitro and in vivo. We found that the expression of hsa-miR-182-5p was downregulated in SONFH-hBMSCs and EVs isolated from those hBMSCs. After tail vein injection, EVs isolated from hBMSCs transfected with hsa-miR-182-5p inhibitor aggravated femoral head necrosis in the SONFH mouse model. We conclude that miR-182-5p regulates bone turnover in the SONFH mouse model via targeting MYD88 and subsequent upregulation of RUNX2 expression. We further assume that EVs derived from hBMSCs resident in SONFH lesion areas aggravate femoral head necrosis by downregulating miR-182-5p secreted from hBMSC located outside these lesions. We suggest that miR-182-5p could provide a novel target for future therapeutic approaches to treat or prevent SONFH. © 2023 American Society for Bone and Mineral Research (ASBMR).

Current management of avascular necrosis of the metacarpal head: a comprehensive literature review

BACKGROUND

Avascular necrosis (AVN) of the metacarpal head is a rare disease that may lead to progressive destruction of the metacarpophalangeal joint and hand function. This study aimed to describe the epidemiology, possible risk factors, clinical presentation, diagnostic workup, and treatment of the rare condition of avascular necrosis of the metacarpal head.

METHODS

Articles were searched using the subject words "Dieterich disease","Mauclaire's disease", and "avascular necrosis of metacarpal head" in the PubMed and Scopus databases. Studies were retained for review after meeting the inclusion criteria. Those outcomes relevant to diagnose and assessing AVN of the metacarpal head and those related to curative management were extracted.

RESULTS

The literature search revealed 45 studies with 55 patients. Although the aetiology of osteonecrosis has not been clearly delineated, AVN of the metacarpal head most commonly arises from trauma but other risk factors may also be involved. Plain radiographs are often negative and therefore likely to be missed. Early-stage osteonecrosis of the metacarpal head was best assessed using MRI. Given the rarity of this condition, there is no clear consensus on the treatment.

CONCLUSIONS

Avascular necrosis of the metacarpal head should be considered in the differential diagnosis of painful metacarpophalangeal joints. An early understanding of this unusual disease will provide an optimal clinical outcome, restoring joint activity, and resolving pain. Nonoperative treatment cannot cure all patients. Surgical management is based on the patient and lesion characteristics.

High-energy focused extracorporeal shock wave prevents the occurrence of glucocorticoid-induced osteonecrosis of the femoral head: A prospective randomized controlled trial

Background

Studies have shown that high-energy focused extracorporeal shock wave therapy (HF-ESWT) has a certain therapeutic effect on glucocorticoid-induced osteonecrosis of the femoral head (ONFH). This study aimed to observe the efficacy and safety of HF-ESWT as a precautionary measure to reduce the probability of glucocorticoid-induced ONFH.

Methods

A prospective randomized controlled trial was designed to evaluate whether HF-ESWT (Group A) can significantly prevent the incidence of glucocorticoid-induced ONFH relative to a control group without shockwave intervention (Group B). MRI was used to assess whether all participants experienced ONFH at 3, 6, and 12 months after the intervention. Continuous scoring was used to evaluate the intervention results: the 10-cm visual analog scale (VAS) was used to evaluate pain, and the hip Harris score (HHS) was used to evaluate the function of the hip joint. Any adverse events were recorded.

Results

153 patients (89 females and 64 males) who had been allocated to group A (75 patients) or Group B (78 patients) were included in the final analysis. The patients were 45.0 ​± ​13.0 years old. There were significant differences between the two groups in MRI diagnosis of ONFH patients (2 cases in Group A, 9 cases in Group B; p ​= ​0.034). Significant differences between groups were found in bilateral hip function measured using the HHS at 6 months (Left p ​= ​0.026; Right p ​= ​0.033) and 12 months (Left p ​= ​0.018; Right p ​= ​0.038). However, there was no difference in the functional results measured at 3 months and the VAS at any points.

Conclusions

This study confirms that HF-ESWT can be successfully used to reduce the probability of glucocorticoid-induced ONFH. Pain and hip dysfunction are common clinical manifestations when ONFH is unavoidable. Therefore, HF-ESWT can be recommended for the prevention and intervention of ONFH high-risk populations receiving high-dose glucocorticoid therapy.

The Translational potential of this article

The effective prevention of HF-ESWT on ONFH after high-dose glucocorticoid application demonstrated its transformation potential as a preventive method in the clinical prevention of glucocorticoid-induced ONFH.

Molecular Imaging of Steroid-Induced Osteonecrosis of the Femoral Head through iRGD-Targeted Microbubbles

Osteonecrosis of the femoral head (ONFH) is a disease that is commonly seen in the clinic, but its detection rate remains limited, especially at the early stage. We developed an ultrasound molecular imaging (UMI) approach for early diagnosis of ONFH by detecting the expression of integrin αvβ3 during the pathological changes in steroid-induced osteonecrosis of the femoral head (SIONFH) in rat models. The integrin αvβ3-targeted PLGA or lipid microbubbles modified with iRGD peptides were fabricated and characterized. Their adhesion efficiency to mouse brain microvascular endothelial cells in vitro was examined, and the better LIPOiRGD was used for further in vivo molecular imaging of SIONFH rats at 1, 3 and 5 weeks; revealing significantly higher UMI signals could be observed in the 3-week and 5-week SIONFH rats but not in the 1-week SIONFH rats in comparison with the non-targeted microbubbles (32.75 ± 0.95 vs. 0.17 ± 0.09 for 5 weeks, p < 0.05; 5.60 ± 1.31 dB vs. 0.94 ± 0.81 dB for 3 weeks, p < 0.01; 1.13 ± 0.13 dB vs. 0.73 ± 0.31 dB for 1 week, p > 0.05). These results were consistent with magnetic resonance imaging data and confirmed by immunofluorescence staining experiments. In conclusion, our study provides an alternative UMI approach to the early evaluation of ONFH.

Huogu injection alleviates SONFH by regulating adipogenic differentiation of BMSCs via targeting the miR-34c-5p/MDM4 pathway

Although the precise pathogenesis of steroid-induced osteonecrosis of femoral head (SONFH) is not yet fully understood, evidence shows miRNAs-mediated posttranscription control directs the adipogenesis of bone marrow mesenchymal stem cells (BMSCs) and plays a pivotal role in the SONFH processes. Huogu injection formulated according to traditional Chinese medicine (TCM) theory has been used to treat SONFH by intra-articular injection. In this study, we asked whether the therapeutic effects of Huogu injection might depend on the inhibition of adipogenic differentiation of BMSCs, and if so, the pathway might be a therapeutic target to promote bone repair. Consequently, miR-34c-5p was upregulated in the dexamethasone (DEX)-treated BMSCs and might participate in the adipogenesis of BMSCs. TargetScan database and the luciferase reporter assay showed miR-34c-5p targeted on the MDM4 and negatively regulated its expression. Huogu injection in vitro inhibited the adipogenesis in the DEX-treated BMSCs by inhibiting the expression levels of PPARγ and C/EBPα, as well as reducing miR-34c-5p to prevent the degradation of MDM4. Moreover, miR-34c-5p mimic or MDM4 knockdown using shRNA neutralized the anti-adipogenesis of Huogu injection in BMSCs. In vivo, the results of X-ray imaging confirmed that Huogu injection alleviated the bone loss in rat SONFH. Consistent with results in vitro, Huogu injection reduced the lipid accumulation, removed the suppression of MDM4 by downregulating the expression of miR-34c-5p, and inhibited the expression of C/EBPα and PPARγ in bone tissues. When the lentivirus encoding miR-34c-5p was conducted by intra-articular injection, the overexpression of miR-34c-5p antagonized the therapeutic effects of Huogu injection. Our results underline the critical importance of the miR-34c-5p/MDM4 pathway in regulating the adipogenic outcome of BMSCs, suggesting the miR-34c-5p as a potentially effective therapeutic target in SONFH. These results further reinforce the potential of Huogu injection as an alternative approach in SONFH.

Evaluation of Radiographic Outcomes after Core Decompression for Osteonecrosis of the Femoral Head: The Beijing University of Chinese Medicine X-ray Evaluation Method

BACKGROUND

Joint-preserving treatments for osteonecrosis of the femoral head (ONFH) are an area of significant interest in orthopaedics as they may restore function and provide durable benefit to patients who would otherwise require early total hip arthroplasty. Studies reporting the outcomes for these procedures generally rely on a combination of radiographic and clinical outcomes. However, there is not currently a standardized radiographic scoring system that allows for objective reporting of radiographic outcomes following these procedures. This article introduces a novel scoring system (Beijing University of Chinese Medicine X-ray evaluation, BUCMXE) based on Anteroposterior (AP) hip radiographs to allow for objective evaluation and comparison of postoperative outcomes following joint-preserving treatments for ONFH.

METHODS

The proposed scoring system utilizes AP radiographs of the hip and consists of a total score (0-10) derived from the sum of subscores in 3 domains: femoral head morphology, osteonecrotic lesion, and degree of osteoarthritis. Each radiographic parameter is scored from 0 (normal) to 3 or 4 (advanced disease). The scoring model was retrospectively applied to a cohort of patients who had undergone core decompression and cancellous bone grafting procedures by the principal investigator.

RESULTS

The BUCMXE provided a clear and reproducible means of quantifying and communicating radiographic changes over the course of follow-up in our study cohort. Statistical analysis demonstrated that the BUCMXE was sensitive to detect the radiographic changes associated with the index procedure. The median total score was reduced from 3 preoperatively to 2 at the initial (3-month) follow-up for this cohort. This change was attributable to the obvious improvement of osteonecrotic lesion in patients who had more advanced disease at the time of their procedure.

CONCLUSION

The BUCMXE system allowed for objective quantification of radiographic changes following joint-preserving hip surgery in our cohort. Statistical analysis of BUCMXE scores demonstrated that the scoring system was sensitive to detect subtle radiographic changes associated with disease progression in the follow-up period.

LEVEL OF EVIDENCE

Therapeutic Level III.

Therapeutic effect of platelet-rich plasma on glucocorticoid-induced rat bone marrow mesenchymal stem cells in vitro

BACKGROUND

Glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) is a progressive and disabling disease caused by long-term or high-dose glucocorticoid use. Decreased osteogenesis and proliferation of bone marrow mesenchymal stem cells (BMSCs) are the main pathogenesis of GIONFH. Platelet-rich plasma (PRP) has been shown to play a promising role in bone regeneration. However, the effects of PRP on glucocorticoid-induced BMSCs inhibition remains elusive. The objective of this study was to explore whether PRP could improve the in vitro biological activities of BMSCs inhibited by high-dose glucocorticoid in vitro.

METHODS

In this study, a dexamethasone (Dex)-induced in vitro cell model was established. The effects of PRP on proliferation, migration, cell cycle and apoptosis of rat BMSCs induced with high-dose Dex compared to BMSC_CTRL, using CCK-8 assay, transwell, flow cytometry and TUNEL assay, respectively. We further performed the alkaline phosphatase (ALP) and alizarin red (ALR) staining to explore the influence of PRP on osteogenic differentiation. Western Blot was used to detect the expression of Bcl-2, Caspase-3, RUNX2 apoptosis, and osteogenic-related proteins.

RESULTS

We observed increased apoptosis rate and Caspase-3 expression, and the decreased migration and osteogenic differentiation, and down-regulation of RUNX-2 and Bcl-2 expression in Dex-induced BMSCs. PRP could reverse these inhibitory effects of Dex, and enhance the BMSCs proliferation, migration, and osteogenic ability in vitro.

CONCLUSION

Our vitro study showed that PRP significantly protected BMSCs from Dex-induced apoptosis, and further promoted BMSCs proliferation, migration, and osteogenic differentiation. This study provides a scientific basis for the prevention and treatment of GIONFH with PRP. Meanwhile, it also lays the foundation for the application of PRP in other musculoskeletal diseases.

Quantitative Magnetic Resonance Imaging of Femoral Head Articular Cartilage Change in Patients with Hip Osteonecrosis Treated with Extracorporeal Shock Wave Therapy

BACKGROUND

Multiple reports have demonstrated the therapeutic potential of extracorporeal shock wave (ESWT) in osteonecrosis of the femoral head (ONFH). However, few studies reported the changes in hip articular cartilage after the intervention. This study aimed to investigate the effect of ESWT on femoral head cartilage using a novel technique, quantitative T2-mapping magnetic resonance imaging.

METHODS

A total of 143 eligible patients with unilateral early-stage ONFH were randomized into the ESWT group and control group. Seventy-three patients in the ESWT group received two sessions of ESWT with oral drug treatment, while seventy patients in the control group received oral drug treatment only. The visual analog pain scale (VAS) and Harris hip score (HHS) at 3-month, 6-month, and 12-month follow-up were used as the clinical evaluation index. The radiological evaluation index used the T2 mapping values, necrotic size, and China-Japan Friendship Hospital (CJFH) classification.

RESULTS

A total of 143 patients (62 females and 81 males) were finally included, and the characteristics before treatment were comparable between the two groups. At the last follow-up (12 months), the T2 values and ΔT2 changes in the ESWT group were all smaller than those in the control group (p=0.042; p=0.039), while the CJFH classification of ONFH and necrotic lesion size were not statistically significant. At 3 months and 6 months, the VAS in the ESWT group was lower than that in the control group (p=0.021; p=0.046) and the HHS in the ESWT group was higher (p=0.028; p=0.039). However, there were no significant differences in the VAS and HHS at 12 months between the ESWT and control groups.

CONCLUSIONS

The results of the current study indicated that, based on drug treatment, ESWT is an effective treatment method for nontraumatic ONFH, which could result in significant pain relief and function restoration. Furthermore, it could delay the injury of femoral head cartilage during the progression of ONFH.

Evolutionary course of the femoral head osteonecrosis: Histopathological - radiologic characteristics and clinical staging systems

Osteonecrosis of the femoral head (ONFH) is a recalcitrant ischemic disorder, which could be classified into two major categories: traumatic and nontraumatic. Regardless of different risk factors, it has been testified that ONFH results from primitive vascular problems, leading to temporary or permanent loss of blood supply to bone tissue. Histopathological and microarchitectural alterations ensues, which is a gradual evolutionary process involving bone marrow and osteocyte necrosis, progressive destruction of subchondral bone, unsuccessful reparative process, and eventual articular collapse and degenerative arthritis. Based on the imaging features of ONFH, different classification systems have been developed to evaluate the severity and prognosis of the disease, which is pivotal for implementation of treatment strategy, especially the joint-preserving surgery. However, patients classified with the same severity stage, especially in the peri-collapse stage, sometimes responded differently after similar joint-preserving surgery. The unusual phenomenon may be attributed to the limitation of the current imaging classification systems, which might underestimate the disease severity, especially when referring to the early stages. In this review, we briefly summarize the etiology and pathogenesis of ONFH. The imaging features and staging classification systems of ONFH are also described. More importantly, we focus on histopathological and microstructural alterations of the femoral head, and provide an overview of their essential contribution to ONFH progression. Given the observation of discordance between imaging characteristics and histopathological alterations, a substantial amount of research on the relationship between imaging and histopathological features is required to further modify and revise the current wide-accepted classification systems.

Prediction of the Collapse of Necrotic Femoral Head by CT and X-Ray Examinations before Hip Replacement Based on Intelligent Medical Big Data

It was to explore the effect of the CT and X-ray examinations before the hip replacement to predict the collapse of the necrotic femoral head under the classification of medical big data based on the decision tree algorithm of the difference grey wolf optimization (GWO) and provide a more effective examination basis for the treatment of patients with the osteonecrosis of the femoral head (ONFH). From January 2019 to January 2021, a total of 152,000 patients with ONFH and hip replacement in the tertiary hospitals were enrolled in this study. They were randomly divided into two groups, the study sample-X group (X-ray examination results) and based-CT group (CT examination results)-76,000 cases in each group. The actual measurement results of the femoral head form the gold standard to evaluate the effect of the two groups of detection methods. The measurement results of X-ray and CT before hip replacement are highly consistent with the detection results of the physical femoral head specimens, which can effectively predict the collapse of ONFH and carry out accurate staging. It is worthy of clinical promotion.

Risk factors and pathogenesis of steroid-induced osteonecrosis of femoral head - A scoping review

Steroid induced osteonecrosis of the femoral head is commonly seen in clinical practice, but yet not fully understood. It is intriguing why only some cases develop and others escape from it. We did an extensive and up to date literature review on it, with the aim to identify its incidence, associated risk factor and pathogenesis. We found that the incidence ranged from 03 to 40%, and was more with associated risk factors. Several risk factors were identified, which included higher dose and prolonged duration of steroid consumption, and underlying disease for which the steroids were given. Pathogenesis of this disease is complex and not yet fully understood. Awareness about this condition and associated risk factors should help the clinicians in identifying the cases who are prone to develop osteonecrosis with the use of steroids.

Management of Posttraumatic Avascular Necrosis of the Proximal Humerus

The etiology of avascular necrosis (AVN) of the proximal humerus can be classified as idiopathic or posttraumatic, the latter being mainly due to proximal humerus fractures. Evidence suggests that posttraumatic AVN may require surgical intervention more often than idiopathic AVN of the proximal humerus. This article provides a comprehensive review of the management of posttraumatic AVN of the proximal humerus. Early stage AVN (stages 1 to 3) is commonly treated with nonoperative intervention or core decompression of the humeral head, whereas later stage disease (stages 4 and 5) may require hemiarthroplasty or total shoulder arthroplasty to restore function. [Orthopedics. 2021;44(6):367-375.].

Corticosteroid induced avascular necrosis and COVID-19: The drug dilemma

The severe and life-threatening nature of the COVID-19 infection, the ARDS (acute respiratory distress syndrome) as well as the cytokine storm induced by the infection, commands lifesaving high doses of steroid therapy. As in all pharmacological therapies adverse effects are present. One such adverse effect which is being reported is corticosteroid induced avascular necrosis of the femoral head/ osteonecrosis of the femoral head. It must be noted that AVN principally affects the femoral head and most commonly the anterolateral aspect thereof as it is the crux of weight bearing.  Corticosteroids induce fat mobilization and this thus innately enhances the likelihood of fat emboli developing from the liver to occlude minor blood vessels in the femur, this thereby compromises the microvascular environment. Superadded to this the steroid therapy disrupts calcium metabolism and homeostasis which induces hypertrophy in the intramedullary fat cells, Gaucher cells and inflammatory cells; whilst increasing the activity of osteoclasts, thus increasing bone resorption and decreasing calcium uptake and deposition; ultimately leading to an insufficiency in the trabecular and cortical bone. This insufficiency thus equates to an increased intraosseous pressure which impedes intramedullary circulation and results in avascular necrosis.  It is evident that avascular necrosis is directly caused by high dose steroid therapy, however the case reports have very clearly indicated that the rapid onset of AVN post recovery from the COVID-19 infection cannot be solely attributed to steroid therapy and that another benefactor induced by the COVID-19 infection is at play. It is thus vital for treating physicians to take cognisance of this adverse effect post recovery and therefore should ensure that prophylactic bisphosphonate therapy is initiated timeously and congruently.

General recommendation for assessment and management on the risk of glucocorticoid-induced osteonecrosis in patients with COVID-19

BACKGROUND/OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a disaster in human medical history and glucocorticoids remain the most promising therapy. Osteonecrosis is a disease caused by reduced intraosseous blood flow to bones in the joints, which will rapidly induce joint destruction. Approximately one-third patients with severe acute respiratory syndrome (SARS) who received high cumulative doses and long treatment durations of glucocorticoids occurred osteonecrosis. Considering the similarity of SARS and COVID-19 on their pathogen, clinical characteristics, and therapeutic strategies, it is particularly desirable to investigate whether osteonecrosis will become a common sequela among convalescent COVID-19 patients.

METHODS

This multi-strategy study was designed by integrating different research methods, such as meta-analysis, systematic review, and cross-sectional investigations to address above study objectives. At first, two meta-analyses were performed on the osteonecrosis incidence among SARS patients and the clinical data of glucocorticoid exposure among COVID-19 patients. Then, a systematic review of low-dosage glucocorticoid associated osteonecrosis and a cross-sectional investigation of glucocorticoid exposure of COVID-19 patients in Wuhan city of China were also conducted. Moreover, the pathogenesis, diagnosis, prevention, and treatment options for osteonecrosis patients with COVID-19 infection were further presented and discussed.

RESULTS

Our meta-analysis showed that 32% of SARS patients had developed osteonecrosis after receiving glucocorticoid treatment with high dose, and our system review supported that low level glucocorticoid exposure might also lead to the occurrence of osteonecrosis. Similarly, 40% of COVID-19 patients had undergone glucocorticoid treatment according to our meta-analysis. The cross-sectional investigation in Wuhan city of China found that the average of cumulative glucocorticoid exposure level was 504 ​mg calculated by the dosage of methylprednisolone. Notably, a confirmed osteonecrosis case was identified from 1406 patients with COVID-19 during our cross-sectional investigation, implying that preventive management of osteonecrosis should be better started with regular clinical follow-up observation.

CONCLUSION

Growing evidence of the glucocorticoid therapy for COVID-19 patients prompts us to establish risk-classification-based early screening and to introduce early prevention protocol of its associated osteonecrosis that will be of clinical significance in favor of improved prognosis of this disease.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

To establish risk-classification-based early screening and to introduce early prevention protocol of glucocorticoid-induced osteonecrosis will be of clinical significance in favor of improved prognosis of COVID-19.

Integrated Analysis of miRNA-mRNA Regulatory Networks Associated with Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) accounts for as many as 18% of total hip arthroplasties. Knowledge of genetic changes and molecular abnormalities could help identify individuals considered to be at a higher risk of developing ONFH. In this study, we sought to identify differentially expressed miRNAs (DEmiRs) and genes (DEGs) associated with ONFH by integrated bioinformatics analyses as well as to construct the miRNA-mRNA regulatory network involving in the pathogenesis of ONFH. We performed differential expression analysis using a gene expression profile GSE123568 and a miRNA expression profile GSE89587 deposited in the Gene Expression Omnibus and identified 47 DEmiRs (24 upregulated miRNAs and 23 downregulated miRNAs) and 529 DEGs (218 upregulated genes and 311 downregulated genes). Gene Ontology enrichment analyses of DEGs suggested that DEGs were significantly enriched in neutrophil activation, cytosol, and ubiquitin-protein transferase activity. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of DEGs revealed that DEGs were significantly enriched in transcriptional misregulation in cancer. DEGs-based miRNA-mRNA regulatory networks were obtained by searching miRNA-mRNA prediction databases, TargetScan, miTarBase, miRMap, miRDB, and miRanda databases. Then, overlapped miRNAs were selected between these putative miRNAs and DEmiRs between ONFH and non-ONFH, and pairs of the DEmiR-DEG regulatory network were finally depicted. There were 12 nodes and 64 interactions for upDEmiR-downDEG regulatory networks and 6 nodes and 16 interactions for downDEmiR-upDEG regulatory networks. Using the STRING database, we established a protein-protein interaction network based on the overlapped DEGs between ONFH and non-ONFH. C5AR1, CDC27, CDC34, KAT2B, CPPED1, TFDP1, and MX2 were identified as the hub genes. The present study characterizes the miRNA profile, gene profile, and miRNA-mRNA regulatory network in ONFH, which may contribute to the interpretation of the pathogenesis of ONFH and the identification of novel biomarkers and therapeutic targets for ONFH.

Effectiveness and safety of traditional Chinese medicine in the treatment of steroid-osteonecrosis of femoral head: A protocol for systematic review and meta-analysis

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a common refractory disease in orthopedics. Overdose glucocorticoid application is a common trigger for ONFH. Traditional Chinese medicine (TCM), as a treatment for ONFH, has been shown to be effective in treating steroid-induced ONFH (SONFH). However, a systematic review and meta-analysis of them is lacking. We aim to systematically review the effectiveness and safety of TCM in the treatment of SONFH.

METHODS

We will search the following databases: PubMed, Embase, the Cochrane Library, MEDLINE, the Chinese Biomedical Literature Database, China Science and Technology Journal Database, China National Knowledge Infrastructure, and Wanfang Data (since the inception of the databases to the present). In addition, we will look for clinical trial registrations, prospective grey literature, relevant conference papers, and established study reference lists. We will use Review Manager 5.3 software for meta-analysis and heterogeneity assessment. We will evaluate the quality of the evidence using a hierarchy of recommendation assessment, development, and evaluation.

RESULTS

This study will systematically evaluate the efficacy and safety of TCM in the treatment of SONFH.

CONCLUSION

This systematic review to evaluate the effectiveness and safety of TCM in the treatment of SONFH will provide updated evidence for clinical application.

INPLASY REGISTRATION NUMBER

INPLASY202170015.

Analysis of MR Signs to Distinguish Between ARCO Stages 2 and 3A in Osteonecrosis of the Femoral Head

BACKGROUND

MRI is the most effective diagnostic tool of osteonecrosis of the femoral head (ONFH), especially for early diagnosis, but its detection of subchondral or cortical fractures is less accurate than CT. Therefore, it is difficult to accurately stage ONFH in the peri-collapse period by MRI.

PURPOSE

To improve the accuracy of MR for distinguishing between Association Research Circulation Osseous (ARCO) stages 2 and 3A in ONFH.

STUDY TYPE

Retrospective.

SUBJECTS

One hundred and fifty five cases of ARCO stage 2/3A of ONFH underwent MR examinations, M/F = 72/83. CT was used as reference standard for collapse, which was decided by an orthopedist and a radiologist in consultation.

FIELD STRENGTH/SEQUENCE

3 T/axial and coronal T₁ -weighted Turbo Spin Echo (T₁ W TSE) sequence, axial T₂ -weighted fat-saturated (T₂ W FS) TSE sequence, and coronal proton density-weighted imaging (PDWI)-FS-Dixon fat/water image.

ASSESSMENT

Five potential MR signs (the maximum width of the necrotic-viable interface, bone marrow edema (BME), irregular articular surface of the femoral head, T₂ heterogeneous high signal, and the absence of a necrotic-viable interface with the morphology of closed loop) were evaluated blindly by five radiologists independently and the total scores of different combinations of MR signs were calculated.

STATISTICAL TESTS

Mann-Whitney U test and Chi-square test were used to evaluate age, gender, and MR signs differences between the two groups. ROC curve was used to access the distinguishing value of MR signs. The consistency of the five radiologists was analyzed by intraclass correlation coefficient.

RESULTS

The area under the curve of the combined MR signs 2 for distinguishing between ARCO stages 2 and 3A was the greatest (0.967), sensitivity and specificity were 100.00% and 88.71% respectively, and greater than 1 was the threshold.

DATA CONCLUSION

Combined MR signs 2 has great values in distinguishing between ARCO stages 2 and 3A in ONFH, thus helping clinical therapy.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 2.

Up-regulation of urinary exosomal hsa-microRNA-200b-3p and hsa-microRNA-206 in patients of steroid-induced osteonecrosis of femoral head

The aim of this study was to determine the value of microRNAs (miRNAs) in urinary exosomes in the diagnosis of steroid-induced osteonecrosis of femoral head (SONFH). RNA was extracted from urinary exosomes from 9 SONFH patients and 9 hip osteoarthritis (HOA) patients with age and gender matched and then miRNAs were analyzed by next generation sequencing. Intriguingly, 15 miRNAs including hsa-miR-200b-3p and hsa-miR-206 were significantly upregulated in exosomes from SONFH patients. Furthermore, qRT-PCR and area under curve (AUC) analysis of an independent cohort of 30 SONFH patients, 10 HOA patients and 10 healthy donors confirmed that hsa-miR-200b-3p and hsa-miR-206 were upregulated in SONFH samples which AUC values were 0.938 (95% CI: 0.828-1) and 0.926 (95% CI: 0.806-1) respectively. GO function, KEGG pathway, miRNAs-mRNAs network and protein-protein interaction (PPI) network were also constructed to analyze potentially pathological mechanisms. The enriched functions and pathways included Hippo, PI3K-Akt, TGF-β and Wnt signaling pathways. The top five hub genes (MAPK1, EP300, RHOA, PIK3CA, and CBL) were selected from PPI network, which consisted of 180 nodes and 518 edges. Collectively, our results showed that hsa-miR-200b-3p and hsa-miR-206 in urinary exosomes might serve as non-invasive biomarkers for SONFH.

[Experimental study on improvement of osteonecrosis of femoral head with exosomes derived from miR-27a-overexpressing vascular endothelial cells]

OBJECTIVE

To investigate whether exosomes derived from miR-27a-overexpressing human umbilical vein endothelial cells (HUVECs)-exo (miR-27a) can promote bone regeneration and improve glucocorticoids (GC) induced osteonecrosis of femoral head (ONFH) (GC-ONFH).

METHODS

The exo (miR-27a) were intended to be constructed and identified by transmission electron microscopy, nanoparticle tracking analysis, Western blot, and real-time fluorescent quantitative PCR (qRT-PCR). qRT-PCR was used to evaluate the effect of exo (miR-27a) in delivering miR-27a to osteoblasts (MC3T3-E1 cells). Alkaline phosphatase staining, alizarin red staining, and qRT-PCR were used to evaluate its effect on MC3T3-E1 cells osteogenesis. Dual-luciferase reporter (DLRTM) assay was used to verify whether miR-27a targeting Dickkopf WNT signaling pathway inhibitor 2 (DKK2) was a potential mechanism, and the mechanism was further verified by qRT-PCR, Western blot, and alizarin red staining in MC3T3-E1 cells. Finally, the protective effect of exo (miR-27a) on ONFH was verified by the GC-ONFH model in Sprague Dawley (SD) rats.

RESULTS

Transmission electron microscopy, nanoparticle tracking analysis, Western blot, and qRT-PCR detection showed that exo (miR-27a) was successfully constructed. exo (miR-27a) could effectively deliver miR-27a to MC3T3-E1 cells and enhance their osteogenic capacity. The detection of DLRTM showed that miR-27a promoted bone formation by directly targeting DDK2. Micro-CT and HE staining results of animal experiments showed that tail vein injection of exo (miR-27a) improved the osteonecrosis of SD rat GC-ONFH model.

CONCLUSION

exo (miR-27a) can promote bone regeneration and protect against GC-ONFH to some extent.

PERK signaling pathway in bone metabolism: Friend or foe?

Osteoblasts and osteoclasts participate in the process of bone remodelling to meet the needs of normal growth and development or repair pathological damage. Endoplasmic reticulum stress (ER stress) can break the intracellular homeostasis of osteoclasts and osteoblasts, which is closely related to abnormal bone remodelling. The double‐stranded RNA‐dependent protein kinase (PKR)‐like ER kinase (PERK) is a key transmembrane protein that regulates ER stress, and growing evidence suggests that the PERK pathway plays a crucial role in regulating bone metabolism under both physiological and pathological conditions. Based on the current findings, we summarized the main mechanisms involved in bone metabolism downstream of the PERK pathway, among which elF2α, FOXO1, CaN, Nrf2 and DAG play a role in regulating the differentiation of osteoblasts and osteoclasts. Importantly, strategies by the regulation of PERK pathway exert beneficial effects in preclinical trials of several bone‐related diseases. Given the importance and novelty of PERK pathway, we provide an overview and discuss the roles of PERK pathway in regulating bone metabolism and its impact on bone‐related diseases. We hope that the development of research in this field will bring a bright future for the treatment of bone‐related diseases.

Functional improvement in hip pathology is related to improvement in anxiety, depression, and pain catastrophizing: an intricate link between physical and mental well-being

Background

Pain catastrophizing, anxiety, and depression are risk factors for poor functional outcomes and worse post-treatment pain that can be treated alongside physical care given to orthopedic patients. While these factors have been shown to be common in patients with hip pathology, there is limited literature that follows these conditions throughout treatment. The purpose of this study was to track psychological factors in patients with various hip pathology to determine if they improved alongside functional measures following treatment.

Methods

Patients presenting to a specialist hip clinic were prospectively evaluated for outcomes of pain catastrophizing, anxiety, depression, and hip function. Pre- and post-treatment assessments were undertaken: Pain Catastrophizing Scale, the Hospital Anxiety Depression Scale, the Hip Outcome Survey, and Hip Disability and Osteoarthritis Outcome Score (HOOS). Patient characteristics were recorded. A correlation analysis, using the Spearman partial correlation coefficient (r_s), was conducted to evaluate the relationship between change in psychological factors with change in functional outcomes.

Results

A total of 201 patients (78 male, 123 female) with a mean age of 53.75 ± 18.97 years were included, with diagnoses of hip dysplasia (n = 35), femoroacetabular impingement (n = 35), lateral trochanteric pain syndrome (n = 9), osteoarthrosis (n = 109), and avascular necrosis of the hip (n = 13). Statistical analysis revealed a significant negative relationship between change in function level (as measured by HOOS ADL) and change in pain catastrophizing (r_s = − 0.373, p < 0.0001), depression (r_s = − 0.363, p < 0.0001), and anxiety (r_s = − 0.264, p = 0.0002). Pain catastrophizing, depression, and anxiety improved with function. Spearman correlation coefficients also revealed that pain catastrophizing, HADS anxiety, and HADS depression improved with improvement in other patient-reported functional outcomes.

Conclusions

Patients with hip pathology often exhibit pain catastrophizing, anxiety, and depression, but improvements in hip functionality are associated with decreased severity of these psychological comorbidities. Exploring this connection demonstrates the correlation between musculoskeletal impairment and psychosocial outcomes and mental health. Perioperative multidisciplinary assessment may be a beneficial part of comprehensive orthopaedic hip care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04001-5.

Novel MRI technique for the quantification of biochemical deterioration in steroid-induced osteonecrosis of femoral head: a prospective diagnostic trial

To explore the novel magnetic resonance imaging techniques, IVIM-DWI and IDEAL-IQ in detecting bone marrow fat and microcirculation in steroid-induced osteonecrosis of the femoral head (SIONFH). In this prospective study, 49 patients (80 hips) with SIONFH taking glucocorticoids and 24 healthy volunteers (48 hips) were recruited and assessed by T1WI, T2WI/fs, IDEAL-IQ and IVIM-DWI. The affected hips, contralateral asymptomatic hips and normal hips, as well as normal, penumbra and necrotic areas in the affected hips, were classified and evaluated. Imaging results were compared with histologic bone sections obtained from SIONFH patients undergoing surgery. The fat fraction (FF) and perfusion fraction (f) differences between groups were analyzed using analysis of variance, the LSD t-test, Pearson correlation analysis and ROC curve analysis. Our results demonstrate that IDEAL-IQ (FF) and IVIM-DWI (f) enable the classification of SIONFH at different ARCO stages. The FF was positively associated with the progression of the disease (r = 0.72), in contrast to f (r = -0.17). The FF and f were significantly different among the necrotic, penumbra and normal areas, and they were negatively correlated with each other (r = -0.37). The diagnostic sensitivity and specificity of IDEAL-IQ were 96.9% and 86.7%, and those of IVIM-DWI were 72.34% and 58.33%, respectively. The FF in contralateral asymptomatic hips was significantly higher than in normal hips, but no difference was found for f. IDEAL-IQ, and not IVIM-DWI, was identified to successfully detect bone marrow fat, which is beneficial to the diagnosis of the severity of SIONFH.

Identification of key non-coding RNAs and transcription factors regulators and their potential drugs for steroid-induced femoral head necrosis

Steroid-induced necrosis of femoral head (SINFH) is a femoral head necrotic disease caused by prolonged use of hormones. The detailed pathogenesis has not been fully demonstrated. In this study, we employed the bioinformatics approach to probe the roles of SINFH inhibitors. Core dysfunction modules related to SINFH was obtained. Meanwhile, GO and KEGG analysis of genes in dysfunction modules are carried out. Furthermore, the pivot prediction analysis of dysfunction modules related to ncRNA and transcription factor (TF) has been performed. The functions of the enriched modules were focused on multiple perspectives, including circulation, gland development, bone development and reconstruction, calcium production, and fatty acid metabolism regulation. The ncRNAs and TFs analysis showed that miR-322-5p, miR-124-3p, miR-125a-3p, and Ctnnb1 were important members of SINFH dysfunction. Drug targets suggested that Zinc and adenosine monophosphate may have an impact on SINFH dysfunction. SINFH was closely related to bone development and reconstruction.

Early detection of steroid-induced femoral head necrosis using 99mTc-Cys-Annexin V-based apoptosis imaging in a rabbit model

Background

At present, the early diagnosis of femoral head necrosis mainly relies on Magnetic resonance imaging (MRI), and most early patients are difficult to make an accurate diagnosis. Therefore, to investigate the early diagnostic value of ^99mTc-Cys-Annexin V Single-photon emission computed tomography (SPECT) imaging were compared with MRI in rabbit models of steroid-induced femoral head necrosis.

Methods

The animal model of steroid-induced femoral head necrosis (SIFHN) was established in 5-month-old healthy New Zealand white rabbits by injecting horse serum into ear vein and methylprednisolone into gluteal muscle, the purpose of modeling is to simulate the actual clinical situation of SIFNH. ^99mTc-Cys-Annexin V SPECT imaging and MRI were performed at 2nd week, 4th week, and 6th week after modeling. After that, histopathology was used to verify the success of modeling. Apoptosis was detected by transmission electron microscopy (TEM) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL).

Results

At 2 weeks after the injection of hormone, ^99mTc-Cys-Annexin V SPECT image showed abnormal radioactive uptake in the bilateral femoral head. And over time, the radioactivity concentration was more obvious, and the ratio of T/NT (target tissue/non-target tissues, which is the ratio of femoral head and the ipsilateral femoral shaft) was gradually increased. In the ^99mTc-Cys-Annexin V SPECT imaging at each time point, T/NT ratio of the model group was significantly higher than that of the control group (P < 0.01); at 4 weeks after the injection of hormone, MRI showed an abnormal signal of osteonecrosis. At 2, 4, and 6 weeks after hormone injection, apoptosis was observed by TUNEL and TEM.

Conclusions

^99mTc-Cys-Annexin V SPECT imaging can diagnose steroid-induced femoral head necrosis earlier than MRI, and has potential application value for non-invasively detecting early and even ultra-early stage of femoral head necrosis.

Exploring the Risk Factors for the Misdiagnosis of Osteonecrosis of Femoral Head: A Case-Control Study

Objective

The purpose of the present study was to evaluate the present situation and risk factors for the misdiagnosis of osteonecrosis of femoral head (ONFH), providing the basis for accurate diagnosis of ONFH.

Methods

For this retrospective study, 1471 patients with ONFH were selected from the China Osteonecrosis of Femoral Head Database (CONFHD). These patients had been recruited between July 2016 and December 2018. According to whether or not they were misdiagnosed, the patients were divided into two groups, with 1168 cases (22–84 years old) included in the diagnosis group and 303 cases (21–80 years old) in the misdiagnosis group. Misdiagnosis was measured using the following criteria: (i) the patient had the same symptoms and signs, and the second diagnosis was not consistent with the initial diagnosis within 6 months; and (ii) the patient was admitted to a hospital participating in CONFHD and the previous diagnosis was inconsistent with the diagnosis given by the expert group. Comparisons of age, visual analogue scale for pain, and body mass index between the two groups were performed using a t‐test. Gender, causes of ONFH, primary diseases requiring corticosteroids, methods of corticosteroid use, corticosteroid species, type of trauma, onset side of the disease, pain side, whether symptoms are hidden, and type of imaging examination at the initial visit were compared using the χ²‐test. Years of alcohol consumption, weekly alcohol consumption, and physician title at the initial visit were compared using a Mann–Whitney U‐test. Furthermore, the statistically significant factors were evaluated using multiple regression analysis to investigate the risk factors of misdiagnosis.

Results

A total of 303 patients (20.6%) were misdiagnosed: 118 cases were misdiagnosed as lumbar disc herniation, 86 cases as hip synovitis, 48 cases as hip osteoarthritis, 32 cases as rheumatoid arthritis, 11 cases as piriformis syndrome, 5 cases as sciatica, and 3 cases as soft‐tissue injury. Whether symptoms are hidden (P = 0.038, odds ratio [OR] = 1.546, 95% confidence interval [CI] = 1.025–2.332), physician title at the initial visit (P < 0.001, OR = 3.324, 95% CI = 1.850–5.972), X‐ray examination (P < 0.001, OR = 4.742, 95% CI = 3.159–7.118), corticosteroids (P < 0.001, OR = 0.295, 95% CI = 0.163–0.534), alcohol (P < 0.001, OR = 0.305, 95% CI = 0.171–0.546), and magnetic resonance imaging (MRI) examination (P = 0.042, OR = 0.649, 95% CI = 0.427–0.985) were each found to be associated with misdiagnosis.

Conclusion

Osteonecrosis of the femoral head is easily misdiagnosed as lumbar disc herniation, hip synovitis, hip osteoarthritis, and rheumatoid arthritis. Patient history of corticosteroid use or alcohol abuse and MRI examination at the initial diagnosis may be protective factors for misdiagnosis. Hidden symptoms, physician title at the initial visit (as attending doctor or resident doctor), and only X‐ray examination at the initial diagnosis may be risk factors for misdiagnosis.