Multicentric epidemiologic study on six thousand three hundred and ninety five cases of femoral head osteonecrosis in China

Multi-sequence MRI-based radiomics: An objective method to diagnose early-stage osteonecrosis of the femoral head

OBJECTIVES

This study investigated the use of radiomics for diagnosing early-stage osteonecrosis of the femoral head (ONFH) by extracting features from multiple MRI sequences and constructing predictive models.

MATERIALS AND METHODS

We conducted a retrospective review, collected MR images of early-stage ONFH (102 from institution A and 20 from institution B) and healthy femoral heads (102 from institution A and 20 from institution B) from two institutions. We extracted radiomics features, handled batch effects using Combat, and normalized features using z-score. We employed the Least absolute shrinkage and selection operator (LASSO) algorithm, along with Max-Relevance and Min-Redundancy (mRMR), to select optimal features for constructing radiomics models based on single, double, and multi-sequence MRI data. We evaluated performance using receiver operating characteristic (ROC) and precision-recall (PR) curves, and compared area under curve of ROC (AUC-ROC) values with the DeLong test. Additionally, we studied the diagnostic performance of the multi-sequence radiomics model and radiologists, compared the diagnostic outcomes of the model and radiologists using the Fisher exact test.

RESULTS

We studied 122 early-stage ONFH and 122 normal femoral heads. The multi-sequence model exhibited the best diagnostic performance among all models (AUC-ROC, PR-AUC for training set: 0.96, 0.961; validation set: 0.96, 0.97; test set: 0.94, 0.94), and it outperformed three resident radiologists on the external testing group with an accuracy of 87.5 %, sensitivity of 85.00 %, and specificity of 90.00 % (p < 0.01), highlighting the robustness of our findings.

CONCLUSIONS

Our study underscored the novelty of the multi-sequence radiomics model in diagnosing early-stage ONFH. By leveraging features extracted from multiple imaging sequences, this approach demonstrated high efficacy, indicating its potential to advance early diagnosis for ONFH. These findings provided important guidance for enhancing early diagnosis of ONFH through radiomics methods, offering new avenues and possibilities for clinical practice and patient care.

Acetabular coverage exerts minimal influence on femoral head collapse and the necessity for surgical intervention in patients with osteonecrosis of femoral head

PURPOSE

The acetabular coverage in osteonecrosis of the femoral head (ONFH) affects the need for surgical intervention, and the collapse of the femoral head remains unclear. This study aimed to evaluate the relation between the acetabular coverage and the need for surgical treatment and femoral head collapse.

METHODS

The study included 158 patients with 252 hips with glucocorticoid administration and idiopathic ONHF without osteoarthritis changes. The mean age at the first visit was 45.2 years, and the mean follow-up period was 92.2 months. All ONFH hips were subsequently divided into two groups: those needing surgical intervention and those without surgery. Additionally, it divided 167 initially non-collapsed hips into those that either later collapsed or not. Radiographic parameters with the centre-edge angle, acetabular roof obliquity, sharp angle, and necrotic location, following the guidelines of the Japanese Investigation Committee, were evaluated.

RESULTS

There were no significant differences in radiographic parameters between the 106 hips that underwent surgery and the 146 hips without surgery. Among the 167 hips without initial collapse, 91 eventually collapsed while 76 did not; their radiographic findings have no significant differences. The necrotic locations were significantly larger in hips requiring surgical intervention or femoral head collapse. Furthermore, 21.8% (55 out of 252 hips) had acetabular dysplasia, which did not significantly correlate with the necessity for surgical treatment or the incidence of femoral head collapse.

CONCLUSIONS

Acetabular coverage has little effect on the necessity for surgical treatment and femoral head collapse in ONFH patients over a long-term follow-up.

Subtrochanteric fracture after core decompression for osteonecrosis of the femoral head: a case report and literature review

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a common clinical disease. Improper treatment can lead to femoral head collapse and hip joint dysfunction. Core decompression is particularly important for early ONFH. However, subtrochanteric fractures after core decompression cause some clinical problems.

CASE PRESENTATION

This article describes a 34-year-old male patient with early ONFH. After core decompression, he suffered a subtrochanteric fracture of the femur while bearing weight on the affected limb when going up stairs. He was subsequently treated with open reduction and intramedullary nail fixation.

CONCLUSION

When core decompression is used to treat ONFH, the location or size of the drill hole, whether a tantalum rod or bone is inserted, and partial weight-bearing of the affected limb may directly affect whether a fracture occurs after surgery. It is hoped that this case report can provide a reference for clinical orthopedic surgeons in the treatment of early ONFH.

Epidemiological investigation and diagnostic analysis of osteonecrosis of the femoral head in three northeastern provinces of China

BACKGROUND

In this retrospective case investigation, we analysed the data of patients with osteonecrosis of the femoral head (ONFH) to reveal demographic and clinical diagnostic features of ONFH in three northeastern provinces of China and provide a reference for its prevention, diagnosis, and treatment.

METHODS

We collected data from patients in Beijing Orthopaedic Hospital of Liaoning, focusing on the aetiology and diagnosis of ONFH. Medical records and self-designed questionnaires were used to collect information for statistical analysis, including age, aetiology, reason for glucocorticoid use, hospital level at first visit, and diagnosis.

RESULTS

In total, 906 patients with complete medical records were included in the analysis. The mean patient age was 47.65 ± 12.12 years. The peak age distribution was in the 40s for men and the 50s for women. Among the total cohort, 72 patients (7.95%; 40 men and 32 women) had traumatic ONFH, 198 (21.85%; 131 men and 67 women) had steroid-induced ONFH, 230 (25.39%; 121 men and 109 women) had idiopathic ONFH, and 406 (44.81%; 397 men and 9 women) had alcohol-induced ONFH. Six hundred and twenty patients were diagnosed with ONFH at the first visit, while 286 patients were misdiagnosed, with a diagnosis rate of 68.43%. The diagnosis rate at the first visit in tertiary hospitals was 76.14%. The diagnosis rate at the first visit in second-class hospitals was 52.07%.ONFH was most likely to be misdiagnosed as lumbar disc herniation.

CONCLUSIONS

Most patients with ONFH in three northeastern provinces of China were middle-aged, male, and had alcohol-induced ONFH. The misdiagnosis rate of ONFH at the first visit was very high, especially for misdiagnosis of lumbar disc herniation, indicating that the diagnosis of ONFH requires further improvement.

Is there still an indication for the Birmingham Hip Resurfacing in femoral head osteonecrosis?

PURPOSE

Osteonecrosis of the femoral head (ONFH) is a progressive hip disease. Hip resurfacing arthroplasty (HRA) is a preferred surgical procedure among hip arthroplasty performed in young patients. The aim of this study is to show the long-term clinical and radiological results of HRA procedures performed for patients suffering from ONFH.

METHODS

Forty-five patients who underwent hip resurfacing with the diagnosis of femoral head osteonecrosis were included in the study. The Harris Hip Score (HHS) was used for clinical scoring of the patients. The blood chromium, cobalt, white blood cell (WBC) count, and CRP levels of patients were checked. Ultrasonography (USG) was performed for all patients at mid-term control checked for pseudo-tumours. For the radiological evaluation, acetabular inclination, stem shaft angle, prothesis-to-neck ratio, osteolysis zones, and heterotopic ossification were used.

RESULTS

The mean age of the patients was 46.6 ± 9.3 years, and the mean follow-up period was 11.83 ± 2.9 years. The mean HHS was 90.3 ± 12.8 for final follow-up. The mean WBC value was 8.2 109/L, mean CRP value was 6.3 mg/L, mean chromium value was 4.9 µg/L, and mean cobalt value was 1.8 µg/L. Inclination changing 0.2°(p = 0.788), stem shaft angle changing 0.7°(p = 0.424), and neck-to-prosthesis ratio changing 0.01°(p = 0.075). No pseudo-tumours were detected in any patients in USG examination.

CONCLUSION

HRA provides long-term implant survival and excellent clinical outcomes for end-stage ONFH patients with low complication rates.

Cortistatin prevents glucocorticoid-associated osteonecrosis of the femoral head via the GHSR1a/Akt pathway

Long-term use of glucocorticoids (GCs) is known to be a predominant cause of osteonecrosis of the femoral head (ONFH). Moreover, GCs can mediate apoptosis of various cell types by exaggerating oxidative stress. We have previously found that Cortistatin (CST) antagonizes oxidative stress and improves cell apoptosis in several conditions. In this study, we detected that the CST expression levels were diminished in patients with ONFH compared with femoral neck fracture (FNF). In addition, a GC-induced rat ONFH model was established, which impaired bone quality in the femoral head. Then, administration of CST attenuated these ONFH phenotypes. Furthermore, osteoblast and endothelial cells were cultured and stimulated with dexamethasone (Dex) in the presence or absence of recombinant CST. As a result, Dex induced impaired anabolic metabolism of osteoblasts and suppressed tube formation in endothelial cells, while additional treatment with CST reversed this damage to the cells. Moreover, blocking GHSR1a, a well-accepted receptor of CST, or blocking the AKT signaling pathway largely abolished the protective function of CST in Dex-induced disorder of the cells. Taken together, we indicate that CST has the capability to prevent GC-induced apoptosis and metabolic disorder of osteoblasts in the pathogenesis of ONFH via the GHSR1a/AKT signaling pathway.

Ortho-silicic Acid Prevents Glucocorticoid-Induced Femoral Head Necrosis by Promoting Akt Phosphorylation to Inhibit Endoplasmic Reticulum Stress-Mediated Apoptosis and Enhance Angiogenesis and Osteogenesis

Glucocorticoid-induced osteonecrosis of the femoral head (SONFH) is the most prevalent form of secondary osteonecrosis affecting the femoral head. Glucocorticoids can cause damage to both vascular endothelial cells and osteoblasts. Previous studies have demonstrated that silicon can improve the resistance of vascular endothelial cells to oxidative stress and positively impact bone health. However, the impact of silicon on SONFH has yet to be investigated. We examined the influence of ortho-silicic acid (OSA, Si(OH)4) on the apoptosis and proliferation of vascular endothelial cells after glucocorticoid induction. Additionally, we evaluated the expression of apoptosis-related genes such as cleaved-caspase-3, Bcl-2 and Bax. The impact of glucocorticoids and OSA on the function of vascular endothelial cells was evaluated through wound healing, transwell and angiogenesis assays. Osteogenic function was subsequently evaluated through alizarin red staining, alkaline phosphatase staining and expression levels of osteogenic genes like RUNX2 and ALP. Moreover, we investigated the potential role of OSA in vivo using the SONFH animal model. At concentrations below 100 μM, OSA exhibits no toxicity on vascular endothelial cells and effectively reverses glucocorticoid-induced apoptosis in these cells. OSA increases the resilience of vascular endothelial cells against oxidative stress and enhances osteoblast differentiation. Our study revealed that glucocorticoids activate endoplasmic reticulum stress, a process that mediates the apoptosis of vascular endothelial cells. OSA ameliorated the endoplasmic reticulum stress associated with glucocorticoids through the increased expression of p-Akt levels. In vivo, OSA treatment effectively improved SONFH by enhancing vascular endothelial cell function and promoting osteogenic differentiation. OSA counteracted the adverse effects of glucocorticoids both in vitro and in vivo, demonstrating a beneficial therapeutic effect on SONFH.

Preclinical models for studying corticosteroid-induced osteonecrosis of the femoral head

Nontraumatic osteonecrosis of the femoral head (ONFH) is a refractory condition that commonly results in femoral head collapse and degenerative arthritis of the hip. In the early stages, surgical procedures for hip preservation, including core decompression (CD), have been developed to prevent progressive collapse of the femoral head. Optimization of bone regeneration and biological augmentation may further enhance the therapeutic efficacy of CD for ONFH. Thus, combining CD with cell-based therapy has recently been proposed. In fact, patients treated with cell-based therapy using autologous bone marrow concentrate demonstrate improved survivorship of the femoral head, compared with conventional CD alone. Preclinical research studies to investigate adjunctive therapies for CD often utilize the rabbit model of corticosteroid-induced ONFH. Mesenchymal stem cells (MSCs) are known to promote osteogenesis and angiogenesis, and decrease inflammation in bone. Local drug delivery systems have the potential to achieve targeted therapeutic effects by precisely controlling the drug release rate. Scaffolds can provide an osteoconductive structural framework to facilitate the repair of osteonecrotic bone tissue. We focused on the combination of both cell-based and scaffold-based therapies for bone tissue regeneration in ONFH. We hypothesized that combining CD and osteoconductive scaffolds would provide mechanical strength and structural cell guidance; and that combining CD and genetically modified (GM) MSCs to express relevant cytokines, chemokines, and growth factors would promote bone tissue repair. We developed GM MSCs that overexpress the anti-inflammatory, pro-reconstructive cytokines platelet-derived growth factor-BB to provide MSCs with additional benefits and investigated the efficacy of combinations of these GM MSCs and scaffolds for treatment of ONFH in skeletally mature male New Zealand white rabbits. In the future, the long-term safety, efficacy, durability, and cost-effectiveness of these and other biological and mechanical treatments must be demonstrated for the patients affected by ONFH.

Predicting efficacy and guiding procedure choice in non-vascularized bone grafting: a CT Radiomics and clinical predictor approach

OBJECTIVES

There is no practical approach for accurately predicting the efficacy of non-vascularized bone grafting (NVBG) and guiding its optimal procedure.

MATERIALS AND METHODS

This study enrolled 153 patients with 182 hips that underwent NVBG procedures. The patients were randomly divided into a training cohort (n = 130) and a validation cohort (n = 52). In the training cohort, radiomics model, clinical model, and combined radiomics-clinical (C-R) model were constructed using Rad-scores and clinical predictors to predict the efficacy of NVBG. The optimal model was visualized by a nomogram and assessed by decision curve analysis (DCA). 128 hips that underwent successful NVBG were then randomized into a new training cohort (n = 92) and a new validation cohort (n = 36), and three models were constructed and validated to predict the choice of NVBG procedure.

RESULTS

Japanese Investigation Committee (JIC) classification, exposure to risk factors postoperative, and Rad-scores consisting of four radiomics features were independent predictors for the efficacy of NVBG (P < 0.05). The C-R model provided better performance in both the training cohort (AUC: 0.818) and validation cohort (AUC: 0.747). To predict the choice of NVBG procedure, the C-R model built by JIC classification and Rad-scores consisting of five radiomics features showed the finest performance in both cohorts (AUC: 0.860 and 0.800, respectively). DCA showed great benefit using the C-R model for the choice of NVBG procedure.

CONCLUSION

The approach integrated by CT radiomics and clinical predictors can be visually and quantitatively applied to predict the efficacy and guide the choice of NVBG procedure with great predictive accuracy.

Knowledge mapping of programmed cell death in osteonecrosis of femoral head: a bibliometric analysis (2000-2022)

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a common, refractory and disabling disease of orthopedic department, which is one of the common causes of hip pain and dysfunction. Recent studies have shown that much progress has been made in the research of programmed cell death (PCD) in ONFH. However, there is no bibliometric analysis in this research field. This study aims to provide a comprehensive overview of the knowledge structure and research hot spots of PCD in ONFH through bibliometrics.

METHOD

The literature search related to ONFH and PCD was conducted on the Web of Science Core Collection (WoSCC) database from 2002 to 2021. The VOSviewers, "bibliometrix" R package and CiteSpace were used to conduct this bibliometric analysis.

RESULTS

In total, 346 articles from 27 countries led by China and USA and Japan were included. The number of publications related to PCD in ONFH is increasing year by year. Shanghai Jiao Tong University, Xi An Jiao Tong University, Wuhan University and Huazhong University of Science and Technology are the main research institutions. Molecular Medicine Reports is the most popular journal in the field of PCD in ONFH, and Clinical Orthopaedics and Related Research is the most cocited journal. These publications come from 1882 authors among which Peng Hao, Sun Wei, Zhang Chang-Qing, Zhang Jian and Wang Kun-zheng had published the most papers and Ronald S Weinstein was cocited most often. Apoptosis, osteonecrosis, osteonecrosis of the femoral head, glucocorticoid and femoral head appeared are the main topics the field of PCD in ONFH. Autophagy was most likely to be the current research hot spot for PCD in ONFH.

CONCLUSION

This is the first bibliometric study that comprehensively summarizes the research trends and developments of PCD in ONFH. This information identified recent research frontiers and hot directions, which will provide a reference for scholars studying PCD in ONFH.

Effects of astragaloside IV on glucocorticoid-induced avascular necrosis of the femoral head via regulating Akt-related pathways

We investigated the role of astragaloside IV (AS-IV) in preventing glucocorticoid-induced avascular necrosis of the femoral head (ANFH) and the underlying molecular mechanisms. Network pharmacology was used to predict the molecular targets of AS-IV. Molecular dynamic simulations were performed to explore the binding mechanism and interaction mode between AS-IV and Akt. Rat models of glucocorticoid-induced ANFH with AS-IV intervention were established, and osteogenesis, angiogenesis, apoptosis and oxidative stress were evaluated before and after blocking the PI3K/Akt pathway with LY294002. The effects of glucocorticoid and AS-IV on bone marrow mesenchymal stem cells and human umbilical vein endothelial cells incubated with and without LY294002 were determined. Downregulated p-Akt expression could be detected in the femoral heads of glucocorticoid-induced ANFH patients and rats. AS-IV increased trabecular bone integrity and vessel density of the femoral head in the model rats. AS-IV increased Akt phosphorylation and upregulated osteogenesis-, angiogenesis-, apoptosis- and oxidative stress-related proteins and mRNA and downregulated Bax, cleaved caspase-3 and cytochrome c levels. AS-IV promoted human umbilical vein endothelial cell migration, proliferation and tube formation ability; bone marrow mesenchymal stem cell proliferation; and osteogenic differentiation under glucocorticoid influence. AS-IV inhibited apoptosis. LY294002 inhibited these effects. AS-IV prevented glucocorticoid-induced ANFH by promoting osteogenesis and angiogenesis via the Akt/Runx2 and Akt/HIF-1α/VEGF pathways, respectively, and suppressing apoptosis and oxidative stress via the Akt/Bad/Bcl-2 and Akt/Nrf2/HO-1 pathways, respectively.

One-year unplanned readmission after total hip arthroplasty in patients with osteonecrosis of the femoral head: rate, causes, and risk factors

BACKGROUND

The primary objectives of this study were to focus on one - year unplanned readmissions after THA in ONFH patients and to investigate rates, causes, and independent risk factors.

METHODS

Between October 2014 and April 2019, eligible patients undergoing THA were enrolled and divided into unplanned readmission within one year and no readmission in this study. All unplanned readmissions within 1 year of discharge were reviewed for causes and the rate of unplanned readmissions was calculated. Demographic information, ONFH characteristics, and treatment-related variables of both groups were compared and analysed.

RESULTS

Finally, 41 out of 876 patients experienced unplanned readmission. The readmission rate was 1.83% in 30 days 2.63% in 90 days, and 4.68% in 1 year. Prosthesis dislocation was always the most common cause at all time points studied within a year. The final logistic regression model revealed that higher risks of unplanned readmission were associated with age > 60 years (P = 0.001), urban residence (P = 0.001), ARCO stage IV (P = 0.025), and smoking (P = 0.033).

CONCLUSIONS

We recommend the introduction of a strict smoking cessation program prior to surgery and the development of comprehensive management strategies, especially for the elderly and end-stage ONFH patients, and pay more attention to preventing prosthesis dislocation in the early days after surgery.

Tanshinone I alleviates steroid-induced osteonecrosis of femoral heads and promotes angiogenesis: in vivo and in vitro studies

BACKGROUND

The impaired blood supply to the bones is an important pathological feature of steroid-induced osteonecrosis of the femoral head (SIONFH). Danshen is a Chinese herb that shows therapeutic effects on SIONFH, but the effects of one of its major bioactive constituents, Tanshinone I (TsI), on SIONFH remain unknown. Here, we evaluated the effects of TsI on SIONFH, particularly focusing on its effects on angiogenesis, in in vivo and in vitro research.

METHODS

SIONFH was induced in Sprague-Dawley rats by an intramuscular injection of methylprednisolone (40 mg/kg) in combination with an intraperitoneal injection of lipopolysaccharide (20 μg/kg). Morphological alterations of the femoral head were observed by dual-energy X-ray absorptiometry and HE staining. Western blot, qRT-PCR, and immunohistochemical/immunofluorescence staining were used to determine gene expression.

RESULTS

TsI (10 mg/kg) alleviated bone loss and rescued the expression of angiogenesis-related molecules (CD31, VWF, VEGF, and VEGFR2) in the femoral heads of SIONFH rats. Notably, TsI rescued the down-regulated expression of SRY-box transcription factor 11 (SOX11) in CD31⁺ endothelial cells in the femoral heads of SIONFH rats. In vitro studies showed that TsI preserved the dexamethasone-harmed angiogenic property (migration and tube formation) of human umbilical vein cells (EA.hy926), suppressed dexamethasone-induced cell apoptosis, reduced pro-apoptotic proteins (cytosolic cytochrome C, Bax, and caspase 3/9) and increased anti-apoptotic protein Bcl-2, whereas silencing of SOX11 reversed these beneficial effects.

CONCLUSIONS

This study demonstrates that TsI alleviates SIONFH and promotes angiogenesis by regulating SOX11 expression. Our work would provide new evidence for the application of TsI to treat SIONFH.

Reliability and repeatability of 2021 ARCO classification and its guiding significance in treatment of nontraumatic osteonecrosis of the femoral head

BACKGROUND

The study was designed to evaluate the interobserver reliability and intraobserver repeatability of the 2021 Association Research Circulation Osseous (ARCO) classification and explore its guiding significance in the treatment of nontraumatic osteonecrosis of the femoral head (ONFH).

METHODS

In this retrospective study, we randomly selected and investigated 50 sets of preoperative computed tomography or magnetic resonance imaging scans from 96 patients (139 hips) to validate the reliability and repeatability of the 2021 ARCO classification. Patients with a nano-hydroxyapatite/polyamide-66 support rod were included in the clinical efficacy study. The Harris hip score (HHS) was used to assess hip function. Femoral head collapse of > 2 mm was considered radiological failure. Total hip arthroplasty (THA) was performed for clinical failure, and follow-up was discontinued.

RESULTS

The average kappa value of interobserver consistency was 0.652. The average rate of consistency was 90.25%, and the average kappa value of intraobserver consistency was 0.836. Eighty-two patients (122 hips) were enrolled and followed up for a mean of 43.57 ± 9.64 months. There was no significant difference in the HHS among the three groups before surgery, but the difference was statistically significant at the last follow-up. Among them, types 1 and 2 had significantly higher scores at the last follow-up than preoperatively (P < 0.05), whereas type 3 had a lower score at the last follow-up than preoperatively, although the difference was not statistically significant (P > 0.05).According to the imaging evaluation, the failure rate of type 1, 2, and 3 at the last follow-up was 0%, 19%, and 87%, respectively. Univariate analysis showed that the femoral head survival rate of radiography was significantly affected by the new classification system (P = 0.00). At the last follow-up, the incidence rate of THA in type 1, 2, and 3 was 5%, 7%, and 31%, respectively. Univariate analysis showed that the femoral head survival rate was significantly affected by the new classification system (P = 0.001).

CONCLUSIONS

The 2021 ARCO classification for early-stage ONFH shows substantial consistency and repeatability. We do not recommend femoral head-preserving surgery for patients with type 3 ONFH.

miRNAs as potential game-changers in bone diseases: Future medicinal and clinical uses

MicroRNAs (miRNAs), short, highly conserved non-coding RNA, influence gene expression by sequential mechanisms such as mRNA breakdown or translational repression. Many biological processes depend on these regulating substances, thus changes in their expression have an impact on the maintenance of cellular homeostasis and result in the emergence of a variety of diseases. Relevant studies have shown in recent years that miRNAs are involved in many stages of bone development and growth. Additionally, abnormal production of miRNA in bone tissues has been closely associated with the development of numerous bone disorders, such as osteonecrosis, bone cancer, and bone metastases. Many pathological processes, including bone loss, metastasis, the proliferation of osteosarcoma cells, and differentiation of osteoblasts and osteoclasts, are under the control of miRNAs. By bringing together the most up-to-date information on the clinical relevance of miRNAs in such diseases, this study hopes to further the study of the biological features of miRNAs in bone disorders and explore their potential as a therapeutic target.

The Lnc-HOTAIR/miR122/PPARγ signaling mediated the occurrence and continuous development of alcohol-induced Osteonecrosis of the femoral head

This study aimed to explore the mechanism of alcohol-induced Osteonecrosis of the femoral head (ONFH) through in vivo and in vitro experiments. In vitro, the Oil Red O staining showed that ethanol promoted extracellular adipogenesis in a dose-dependent manner. ALP staining and alizarin red staining showed that ethanol inhibited the formation of extracellular mineralization in a dose-dependent manner. The Oil Red O staining showed that miR122 mimics and Lnc-HOTAIR SiRNA rescued extracellular adipogenesis induced by ethanol in BMSCs. Besides, we found that the high expression of PPARγ in BMSCs recruited histone deacetylase 3 (HDAC3) and histone methyltransferase (SUV39H1), which reduced the histone acetylation level and increased the histone methylation level in the miR122 promoter region, respectively. In vivo, the levels of H3K9ac, H3K14ac, and H3K27ac of miR122 promoter region in the ethanol group were significantly decreased compared to the control group, respectively. The levels of H3K9me2 and H3K9me3 of miR122 promoter region in the ethanol group were significantly increased compared to the control group. Lnc-HOTAIR/miR-122/PPARγ signaling mediated the alcohol-induced ONFH in the rat model. Furthermore, the persistent decrease of miR122 expression mediated the continuous progress of alcohol-induced ONFH after stopping alcohol consumption.

Bone tissue engineering for treating osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) is a devastating and complicated disease with an unclear etiology. Femoral head-preserving surgeries have been devoted to delaying and hindering the collapse of the femoral head since their introduction in the last century. However, the isolated femoral head-preserving surgeries cannot prevent the natural progression of ONFH, and the combination of autogenous or allogeneic bone grafting often leads to many undesired complications. To tackle this dilemma, bone tissue engineering has been widely developed to compensate for the deficiencies of these surgeries. During the last decades, great progress has been made in ingenious bone tissue engineering for ONFH treatment. Herein, we comprehensively summarize the state-of-the-art progress made in bone tissue engineering for ONFH treatment. The definition, classification, etiology, diagnosis, and current treatments of ONFH are first described. Then, the recent progress in the development of various bone-repairing biomaterials, including bioceramics, natural polymers, synthetic polymers, and metals, for treating ONFH is presented. Thereafter, regenerative therapies for ONFH treatment are also discussed. Finally, we give some personal insights on the current challenges of these therapeutic strategies in the clinic and the future development of bone tissue engineering for ONFH treatment.

Decreased serum MMP-9 levels in patients with nontraumatic osteonecrosis of the femoral head

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1) are involved in the pathological mechanism of osteonecrosis of the femoral head (ONFH). This study aimed to investigate the relationship of serum MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio with disease severity in patients with nontraumatic ONFH.

METHODS

Serum levels of MMP-9 and TIMP-1 among 102 nontraumatic ONFH patients and 96 healthy individuals were determined by enzyme-linked immunosorbent assay (ELISA). Imaging severity was determined using the FICAT classification system. The Harris hip score (HHS) and visual analogue scale (VAS) were used to evaluate clinical progress. The correlations of serum MMP-9 and TIMP-1 levels with imaging severity and clinical progress was evaluated statistically. The diagnostic value of MMP-9 for NONFH disease severity was evaluated by examining receiver operating characteristic (ROC) curves.

RESULTS

The serum MMP-9 levels and the MMP-9/TIMP-1 ratio were significantly increased in patients with ONFH compared to normal controls, and TIMP-1 levels did not differ between the two groups. Serum MMP-9 levels and the MMP-9/TIMP-1 ratio were positively correlated with FICAT stage and VAS and were negatively correlated with the HHS score. The ROC curve results indicated that MMP-9 could be used as a potential marker of nontraumatic ONFH imaging progression.

CONCLUSIONS

We hypothesize that increased MMP-9 expression and an imbalance in the MMP-9/TIMP-1 ratio play a role in the development of ONFH and are correlate with the severity of ONFH. The determination of MMP-9 can be a useful tool to assess the severity of the disease in patients with nontraumatic ONFH.

Bioinformatics-Based Analysis of Key Genes in Steroid-Induced Osteonecrosis of the Femoral Head That Are Associated with Copper Metabolism

Osteonecrosis of the femoral head (ONFH) is a common disabling disease. Copper has positive effects on cells that regulate bone metabolism. However, the relationship between copper metabolism (CM) and steroid-induced ONFH (SONFH) remains unclear. The GSE123568 dataset was downloaded from the Gene Expression Omnibus. The differentially expressed CM-related SONFH genes (DE-CMR-SONFHGs) were identified via differential analysis and weighted gene coexpression network analysis (WGCNA). Receiver operating characteristic (ROC) analysis was performed for the predictive accuracy of key genes. Targeting drugs and the copper death-related genes (CDRGs) relevant to key genes were investigated. The bioinformatics results were confirmed via quantitative real-time polymerase chain reaction (qRT–PCR) and Western blot (WB) analysis. Two out of 106 DE-CMR-SONFHGs were identified as key genes (PNP and SLC2A1), which had diagnostic value in distinguishing SONFH from control samples and were related to various immune cell infiltrations. Eleven PMP-targeting drugs and five SLC2A1-targeting drugs were identified. The qRT–PCR, as well as WB, results confirmed the downregulation PNP and SLC2A1 and high expression of the CDRGs DLD, PDHB, and MTF1, which are closely related to these two key genes. In conclusion, PNP and SLC2A1 were identified as key genes related to SONFH and may provide insights for SONFH treatment.

Accumulation of Fat Not Responsible for Femoral Head Necrosis, Revealed by Single-Cell RNA Sequencing: A Preliminary Study

The etiology of osteonecrosis of the femoral head (ONFH) is not yet fully understood. However, ONFH is a common disease with high morbidity, and approximately one-third of cases are caused by glucocorticoids. We performed single-cell RNA sequencing of bone marrow to explore the effect of glucocorticoid on ONFH. Bone marrow samples of the proximal femur were extracted from four participants during total hip arthroplasty, including two participants diagnosed with ONFH for systemic lupus erythematosus (SLE) treated with glucocorticoids (the case group) and two participants with femoral neck fracture (the control group). Unbiased transcriptome-wide single-cell RNA sequencing analysis and computational analyses were performed. Seventeen molecularly defined cell types were identified in the studied samples, including significantly dysregulated neutrophils and B cells in the case group. Additionally, fatty acid synthesis and aerobic oxidation were repressed, while fatty acid beta-oxidation was enhanced. Our results also preliminarily clarified the roles of the inflammatory response, substance metabolism, vascular injury, angiogenesis, cell proliferation, apoptosis, and dysregulated coagulation and fibrinolysis in glucocorticoid-induced ONFH. Notably, we list the pathways that were markedly altered in glucocorticoid-induced ONFH with SLE compared with femoral head fracture, as well as their common genes, which are potential early therapeutic targets. Our results provide new insights into the mechanism of glucocorticoid-induced ONFH and present potential clues for effective and functional manipulation of human glucocorticoid-induced ONFH, which could improve patient outcomes.

Hip Preservation or Total Hip Arthroplasty? A Retrospective Case-Control Study of Factors Influencing Arthroplasty Decision-Making for Patients with Osteonecrosis of the Femoral Head in China

OBJECTIVE

At present, there is no consensus or guidance on indications for osteonecrosis of the femoral head (ONFH) patients to receive hip arthroplasty (THA) treatment. This study aims to explore the factors that influence the decision-making for THA in patients with ONFH, and to provide references for clinical decision for ONFH patients to be indicated for THA or hip preservation.

METHODS

This retrospective case-control study involved data for ONFH patients from July 2016 to October 2021 from the China Osteonecrosis of the Femoral Head Database (CONFHD). The patients with ONFH, and unilateral hip affected at the first visit were divided into THA group and non-THA group according to if they had undergone THA treatment. The differences between the two groups of patients in terms of gender, age at the time of consultation, body mass index (BMI), etiology, onset side, association research circulation osseous (ARCO) stage, hip joint function, visual analog scale (VAS), etc. were analyzed. Multivariate binomial logistic regression analysis was then applied to evaluate the risk factors of ONFH patients who underwent THA during the first visit.

RESULTS

A total of 640 patients were recruited for analysis, including 209 cases from the THA group and 431 cases from the non-THA group. The results of univariate analysis showed that the two groups of patients were significantly different in the following six indicators: age (59 vs. 46, Z = -9.58, p < 0.001), duration of disease (78 vs. 17, Z = -16.14, p < 0.001), gender composition (χ²  = 8.09, p = 0.004), disease etiology (χ²  = 33.04, p < 0.001), ARCO stage (χ²  = 334.86, p < 0.001), flexion of hip joint (χ²  = 172.33, p < 0.001). However, the comparison between the two groups on VAS (Z = -0.82, p = 0.41), BMI (Z = -1.35, p = 0.18), and onset side (χ²  = 1.53, p = 0.22) did not obviously differ. The results regression analysis showed that the age at the time of consultation, duration of disease, ARCO stage, and the hip joint function affected the decision making if the patients should undergo THA. The results of receiver operating characteristic curve (ROC) analysis showed that aforementioned indicators were satisfactory in predicting whether patients with ONFH would be treated with THA. The regression model using the above four indicators as comprehensive indicators has satisfactory performance in predicting whether to perform THA, and the area under the curve (AUC) is 93.94%.

CONCLUSION

These factors such as age, duration of disease, ARCO stage, and hip flexion function should be considered comprehensively before making decisions to perform THA or not in our clinical practice.

Intraoperative picture of hip joint lesion in ankylosing spondylitis: data from a retrospective analysis

In population of Russian patients with ankylosing spondylitis (AS), the frequency of clinical manifestations (pain and limitation of functions) of coxitis reaches 56%. Total hip arthroplasty (THA) can be considered as the only alternative that can relieve the suffering of the patient. Radiography and magnetic resonance imaging are widely used methods for assessing structural damage to the hip joint in AS. However, at the moment these methods can’t allow us to fully describe the lifetime changes of these joints. The aim of the study: to analyze the external changes of the femoral heads (HF) and acetabulums during the THA in patients with AS. Materials and methods. The retrospective study included 170 patients with a reliable diagnosis of AS, who met the modified New York criteria of 1984, who were treated in the traumatological and orthopedic department of the V.A. Nasonova Research Institute of Rheumatology in the period from 1998 to 2020, all patients underwent THA as planned. Most of them were male (80.6%). The average age of patients was 38.1±11.3 years and the average duration of the disease since the onset of the first symptoms was 17.0±8.5 years. The duration of pain in hip joints before performing THA is 7.4±4.8 years. The assessment of macroscopic changes in the FH and acetabulum was performed intraoperatively. Results and discussion. Acetabulum protrusion was detected in 108 (63.5%) patients, bone cysts – in 65 (38.2%). Filling of acetabulum with granulation tissue was recorded in 155 (91.2%) patients, presence of osteophytes on its edges – in 153 (90%). Cartilage in the acetabulum was completely absent in 122 (71.8%) patients. FH deformation was detected in 98.2% of cases, erosion in 46.4%. Cartilage on FH was completely absent in 130 (76.5%) patients. In 119 (70%) patients, macroscopic signs of osteonecrosis of FH were found. 79 (46.4%) patients had ankylosis of the hip joint, including fibrous ankylosis – in 77.2% of patients and bone ankylosis – in 22.8%. Conclusion. In patients with AS, the necessity for THA occurs on average after 7.4±4.8 years from the moment of the appearance of first clinical signs of coxitis. In 70% of cases, the macroscopic picture of hip joint lesion was characterized by the development of Avascular necrosis of the femur head (AVNFH), in most patients there was no cartilage in the most loaded segments of acetabulum and FH, in almost half of cases – ankylosis of hip joint and mainly fibrous (77.2%).

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.

Identification of Inflammation-Related Genes and Exploration of Regulatory Mechanisms in Patients with Osteonecrosis of the Femoral Head

Background

Osteonecrosis of the femoral head (ONFH) is a disabling orthopedic disease, which is impacted by infiltration of immune cells. Thus, the aim of the current research was to determine the inflammation-related biomarkers in ONFH.

Methods

GSE123568 dataset with control and steroid-induced osteonecrosis of the femoral head (SONFH) samples were downloaded from Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were detected by limma R package and weighted gene co-expression network analysis (WGCNA) was used to explore the co-expression genes and modules. We obtained inflammation-related genes (IRGs) from the Molecular Signatures Database (MSigDB). Then, the IRGs associated with SONFH (IRGs-SONFH) were screened out and analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. A protein-protein interaction (PPI) network was established using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and hub genes were identified by the MCODE algorithm. Based on the hub genes, we constructed a lncRNA-miRNA-mRNA network.

Results

We identified 535 DEGs between control and SONFH samples. The WGCNA clearly indicated that the brown module was most significantly associated with SONFH. We identified 25 IRGs-SONFH through WGCNA module genes, DEGs and IRGs. A total of 4 hub genes (CD14, CYBB, NOD2, and TLR1) were identified by Cytoscape. Receiver operating characteristic (ROC) curve analysis determined that the expressions of the four genes could distinguish SONFH from controls as evidenced by the area under the curve (AUC) greater than 0.7. Finally, we constructed a competitive endogenous RNA (ceRNA) network which included 67 lncRNAs, 1 miRNA (hsa-miR-320a), and 1 mRNA (NOD2).

Conclusions

Our study identified 4 hub genes as potential inflammation-related biomarkers of SONFH. Moreover, we proposed a ceRNA network of lncRNAs targeting hsa-miR-320a, hsa-miR-320a, and NOD2 as a potential RNA regulatory pathway that controls disease progression in ONFH.

PFKP and GPC6 Variants Were Correlated with Alcohol-Induced Femoral Head Necrosis Risk in the Chinese Han Population

Background

Osteonecrosis of the femoral head (ONFH) is a common joint disease caused by excessive drinking, genetic factors, etc. The purpose of this study was to investigate the association between PFKP and GPC6 variants and alcohol-induced ONFH (AIONFH) risk in the Chinese Han population.

Methods

This study genotyped 9 selected single nucleotide polymorphisms (SNPs) in 402 males by Agena MassARRAY Assay. By calculating odds ratios (ORs) and 95% confidence intervals (CIs), we assessed the effect of gene polymorphisms on AIONFH occurrence. False-positive report probability (FPRP) analysis and power were also used to evaluate the significant results. Multifactor dimensionality reduction (MDR) software was also utilized to predict the association between the selected SNPs and AIONFH risk.

Results

The overall analysis showed that PFKP rs10903966 and GPC6 rs7320969 were correlated with AIONFH risk. GPC6 rs4773724 was associated with a reduced risk of AIONFH, while individuals with GPC6 rs9523981 CC genotype had a higher risk of AIONFH than individuals with the other genotypes among people under 42 years old. Based on stratified analysis of necrotic sites, rs7320969 was related to a decreased risk of AIONFH, while rs10903966 and rs9523981 were related to an increased risk of AIONFH. In addition, rs1008993 and rs7320969 were observed to be linked to AIONFH risk in patients at different clinical stages. Meanwhile, there were significant differences in TC, TG, platelet, ApoA1 and ApoB levels among subjects with different genotypes of rs1008993, rs9523981, rs7320969 and rs59624626. The results of MDR showed that rs11251720 and rs7320969 may play a synergistic role in predicting the risk of AIONFH.

Conclusion

PFKP rs10903966 and GPC6 rs9523981 were associated with an increased risk of AIONFH, while GPC6 (rs7320969 and rs4773724) were correlated with a decreased risk of AIONFH. This result will need further experiments to verify.

Therapeutic perspectives of exosomes in glucocorticoid-induced osteoarthrosis

Exosomes are widely involved in a variety of physiological and pathological processes. These important roles are also hidden in the physiological processes related to bone. Chondrocytes, osteoblasts, synovial fibroblasts, and bone marrow mesenchymal stem cells produce and secrete exosomes, thereby affecting the biology process of target cells. Furthermore, in the primary pathogenesis of osteoarthrosis induced by steroid hormones, mainly involve glucocorticoid (GC), the exosomes have also widely participated. Therefore, exosomes may also play an important role in glucocorticoid-induced osteoarthrosis and serve as a promising treatment for early intervention of osteoarthrosis in addition to playing a regulatory role in malignant tumors. This review summarizes the previous results on this direction, systematically combs the role and therapeutic potential of exosomes in GC-induced osteoarthrosis, discusses the potential role of exosomes in the treatment and prevention of GC-induced osteoarthrosis, and reveals the current challenges we confronted.

Composite indices of femoral neck strength predicts the collapse of steroid-associated osteonecrosis of the femoral head: a retrospective study

PURPOSES

The purpose of this study was to investigate the predictive effect exerted by composite indices of femoral neck strength (compressive strength index (CSI), bending strength index (BSI) and impact strength index (ISI) on the femoral head collapse in steroid-associated ONFH patients.

METHODS

Nonoperative steroid-associated osteonecrosis of the femoral head (ONFH) patients from 2017 to 2019 were selected. The patients fell into the collapsed group and the non-collapsed group according to whether the femoral head collapsed. CSI, BSI and ISI were calculated. Moreover, bone turnover markers were measured. The statistical analysis was conducted on the predictive effects of composite indices of femoral neck strength and bone turnover index on ONFH collapse.

RESULTS

A total of 62 patients were included. The mean CSI, BSI and ISI were significantly lower in the collapsed group than those in the non-collapsed group (P < 0.05). CSI, ISI,t-P1NP and β-CTx were suggested as the protective risk factors for the femoral head collapse in ONFH patients. The ISI area under the curve values was 0. 878.The mean survival time of the hips of patients with ISI greater than 0.435 was greater (P < 0.05) than that of patients with ISI less than 0.435.

CONCLUSION

The composite indices of femoral neck strength can predict steroid-associated ONFH femoral head collapse more effectively than the bone turnover markers. The ISI value of 0.435 is a potential cut-off value, lower than this value can predict the early collapse of steroid-associated ONFH.

C/EBPα regulates the fate of bone marrow mesenchymal stem cells and steroid-induced avascular necrosis of the femoral head by targeting the PPARγ signalling pathway

BACKGROUND

The imbalance of osteogenic/adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is closely related to steroid-induced avascular necrosis of the femoral head (SANFH). We aimed to investigate the epigenetic mechanism of intramedullary fat accumulation and continuous osteonecrosis after glucocorticoid (GC) withdrawal in SANFH.

METHODS

An SANFH model was established in SD rats, which received an intermittent high GC dose for the first 4 weeks followed by an additional 4 weeks without GC. We explored the synergistic effects and mechanisms of C/EBPα and PPARγ on the differentiation of BMSCs by lentivirus-mediated gene knockdown and overexpression assays. A chromatin immunoprecipitation assay was performed to identify epigenetic modification sites on PPARγ in vivo and in vitro.

RESULTS

In the SANFH model, intramedullary fat was significantly increased, and the transcription factors C/EBPα and PPARγ were upregulated simultaneously in the femoral head. In vitro, C/EBPα promoted adipogenic differentiation of BMSCs by targeting the PPARγ signalling pathway, while overexpression of C/EBPα significantly impaired osteogenic differentiation. Further studies demonstrated that histone H3K27 acetylation of PPARγ played an important role in the epigenetic mechanism underlying SANFH. C/EBPα upregulates the histone H3K27 acetylation level in the PPARγ promoter region by inhibiting HDAC1. Additionally, inhibiting the histone acetylation level of PPARγ effectively prevented adipogenic differentiation, thus slowing the progression of SANFH.

CONCLUSIONS

Our results demonstrate the molecular mechanism by which C/EBPα regulates PPARγ expression by acetylating histones and revealed the epigenetic phenomenon in SANFH for the first time.

Vitamin B2 Prevents Glucocorticoid-Caused Damage of Blood Vessels in Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) is a disorder that can cause collapse of the femoral head. The damage and dysfunction of femoral head microvascular endothelial cells are related to the pathogenesis of glucocorticoid-induced ONFH. Reports suggest that vitamin B₂ can promote osteoblast differentiation and prevent low bone mineral density and prevent reperfusion oxidative injury. To explore the effect and possible molecular mechanism of vitamin B₂ on the ONFH and Human Umbilical Vein Endothelial Cells (HUVECs), we performed a rat model of ONFH by dexamethasone. The rats were randomly divided into four groups: control group, vitamin B₂ group, dexamethasone group, and dexamethasone combined with vitamin B₂ treatment group. HUVECs were used to further prove the role and mechanism of vitamin B₂ in vitro. In patients, according to immunohistochemical and qRT-PCR of the femoral head, the angiogenic capacity of the ONFH femoral head is compromised. In vivo, it showed that vitamin B₂ could inhibit glucocorticoid-induced ONFH-like changes in rats by suppressing cell apoptosis, promoting the regeneration of blood vessels, and increasing bone mass. According to in vitro results, vitamin B₂ could induce the migration of HUVECs, enhance the expression of angiogenesis-related factors, and inhibit glucocorticoid-induced apoptosis. The underlying mechanism may be that vitamin B₂ activates the PI3K signaling pathway. Vitamin B₂ alleviated dexamethasone-induced ONFH, and vitamin B₂ could promote the proliferation and migration of HUVECs and inhibit their apoptosis by activating the PI3K/Akt signaling pathway. Vitamin B₂ may be a potentially effective treatment for ONFH.

Animal Models of Femur Head Necrosis for Tissue Engineering and Biomaterials Research

Femur head necrosis, also known as osteonecrosis of the femoral head (ONFH), is a widespread disabling pathology mostly affecting young and middle-aged population and one of the major causes of total hip arthroplasty in the elderly. Currently, there are limited number of different clinical or medication options for the treatment or the reversal of progressive ONFH, but their clinical outcomes are neither satisfactory nor consistent. In pursuit of more reliable therapeutic strategies for ONFH, including recently emerged tissue engineering and biomaterials approaches, in vivo animal models are extremely important for therapeutic efficacy evaluation and mechanistic exploration. Based on the better understanding of pathogenesis of ONFH, animal modeling method has evolved into three major routes, including steroid-, alcohol-, and injury/trauma-induced osteonecrosis, respectively. There is no consensus yet on a standardized ONFH animal model for tissue engineering and biomaterial research; therefore, appropriate animal modeling method should be carefully selected depending on research purposes and scientific hypotheses. In this work, mainstream types of ONFH animal model and their modeling techniques are summarized, showing both merits and demerits for each. In addition, current studies and experimental techniques of evaluating therapeutic efficacy on the treatment of ONFH using animal models are also summarized, along with discussions on future directions related to tissue engineering and biomaterial research. Impact statement Exploration of tissue engineering and biomaterial-based therapeutic strategy for the treatment of femur head necrosis is important since there are limited options available with satisfactory clinical outcomes. To promote the translation of these technologies from benchwork to bedside, animal model should be carefully selected to provide reliable results and clinical outcome prediction. Therefore, osteonecrosis of the femoral head animal modeling methods as well as associated tissue engineering and biomaterial research are overviewed and discussed in this work, as an attempt to provide guidance for model selection and optimization in tissue engineering and biomaterial translational studies.

Glucocorticoid-induced loss of beneficial gut bacterial extracellular vesicles is associated with the pathogenesis of osteonecrosis

Osteonecrosis of the femoral head (ONFH) commonly occurs after glucocorticoid (GC) therapy. The gut microbiota (GM) participates in regulating host health, and its composition can be altered by GC. Here, this study demonstrates that cohousing with healthy mice or colonization with GM from normal mice attenuates GC-induced ONFH. 16S rRNA gene sequencing shows that cohousing with healthy mice rescues the GC-induced reduction of gut Lactobacillus animalis. Oral supplementation of L. animalis mitigates GC-induced ONFH by increasing angiogenesis, augmenting osteogenesis, and reducing cell apoptosis. Extracellular vesicles from L. animalis (L. animalis-EVs) contain abundant functional proteins and can enter the femoral head to exert proangiogenic, pro-osteogenic, and antiapoptotic effects, while its abundance is reduced after exposure to GC. Our study suggests that the GM is involved in protecting the femoral head by transferring bacterial EVs, and that loss of L. animalis and its EVs is associated with the development of GC-induced ONFH.

Cryogenic 3D Printing of ß-TCP/PLGA Composite Scaffolds Incorporated With BpV (Pic) for Treating Early Avascular Necrosis of Femoral Head

Avascular necrosis of femoral head (ANFH) is a disease that is characterized by structural changes and collapse of the femoral head. The exact causes of ANFH are not yet clear, but small advances in etiopathogenesis, diagnosis and treatment are achieved. In this study, ß-tricalcium phosphate/poly lactic-co-glycolic acid composite scaffolds incorporated with bisperoxovanadium [bpV (pic)] (bPTCP) was fabricated through cryogenic 3D printing and were utilized to treat rat models with early ANFH, which were constructed by alcohol gavage for 6 months. The physical properties of bPTCP scaffolds and in vitro bpV (pic) release from the scaffolds were assessed. It was found that the sustained release of bpV (pic) promoted osteogenic differentiation and inhibited adipose differentiation of bone marrow-derived mesenchymal stem cells. Micro-computed tomography scanning and histological analysis confirmed that the progression of ANFH in rats was notably alleviated in bPTCP scaffolds. Moreover, it was noted that the bPTCP scaffolds inhibited phosphatase and tensin homolog and activated the mechanistic target of rapamycin signaling. The autophagy induced by bPTCP scaffolds could partially prevent apoptosis, promote osteogenesis and angiogenesis, and hence eventually prevent the progression of ANFH, suggesting that the bPTCP scaffold are promising candidate to treat ANFH.

The polymorphisms of MIR31HG gene is correlated with alcohol-induced osteonecrosis of the femoral head in Chinese Han male population

BACKGROUND

Alcoholic osteonecrosis of the femoral head (ONFH) is a multifaceted illness that seriously disturbs the patients' quality of life. The role of lncRNAs in alcoholic ONFH has attracted widespread attention in recent years. This study mainly explored whether MIR31HG polymorphism affects the risk of ONFH.

METHODS

There were 733 males (308 alcohol-induced ONFH patients and 425 healthy controls). Seven single nucleotide polymorphisms from MIR31HG were genotyped using the Agena MassARRAY platform. Odds ratio (OR) and 95% confidence intervals (CI) via logistic regression was applied to assess the contribution of MIR31HG variants to alcoholic ONFH susceptibility.

RESULTS

We found that rs10965059 was related to a lower risk of alcoholic ONFH in the overall, age, and necrotic sites analysis. Rs10965064 also showed a risk-reducing effect in the occurrence of alcoholic ONFH patients older than 40 years old.

CONCLUSIONS

We confirmed that MIR31HG variants have a significant correlation with the occurrence of alcoholic ONFH among the Chinese Han male population. our findings may provide new ideas for understanding the effect of MIR31HG on the prevention and diagnosis of alcoholic ONFH.

Global research trends of steroid-induced osteonecrosis of the femoral head: A 30-year bibliometric analysis

OBJECTIVE

To explore the global research trends and hotspots of steroid-induced osteonecrosis of the femoral head (SONFH) through qualitative and quantitative analysis of bibliometrics.

METHODS

All publications on SONFH published from 1992 to 2021 were extracted from the Web of Science Core Collection database. CiteSpace was used for the visualization analysis of major countries, active institutions, productive authors, and the burst of keywords. VOSviewer was used for coupling analysis of countries/regions, institutions, and authors. Microsoft Excel 2017 was used for statistical analysis, drawing bar charts, pie charts, and cumulative area charts. The software of MapInfo was used to draw the distribution map of the publications.

RESULTS

A total of 780 publications were included for analyses. The most productive year was 2020 with 98 records. China was the most influential country with 494 publications, an H-index of 59, and total citations of 16820. The most prolific institution was Shanghai Jiaotong University in China with 53 publications and 998 citations. Clinical Orthopaedics and Related Research (IF = 4.755, 2021) was the most active journal with 26 articles. The hot keywords were "osteonecrosis", "avascular necrosis", "osteogenic differentiation", "proliferation", "PPAR gamma", "apoptosis", "oxidative stress", "genetic polymorphism" and "mesenchymal stem cells". The keywords like "proliferation", "PPAR gamma" and "genome-wide" have emerged in recent years.

CONCLUSION

The number of publications in SONFH has increased significantly in the last three decades. The pathologic mechanism of SONFH gathered most research interests. Genomics and cell molecular biology of SONFH are the research frontiers.

The Therapeutic Effect of Huo Xue Tong Luo Capsules in Association Research Circulation Osseous (ARCO) Stage II Osteonecrosis of the Femoral Head: A Clinical Study With an Average Follow-up Period of 7.95 Years

Background: Huo Xue Tong Luo (HXTL) capsules are an oral preparation that could relieve pain and ameliorate osteonecrosis in patients with asymptomatic osteonecrosis of femoral head (ONFH). We wanted to verify whether it could be a treatment option for ARCO stage II ONFH.

Methods: A total of 44 patients (66 hips) with ARCO stage II ONFH were recruited from June 1996 to October 2013 (clinical trial registry number: ChiCTR-RPC-15006,290). HXTL capsules were given under a specific protocol, and the endpoint was set as femoral head collapse. The clinical indicators [including visual analog scale (VAS) and Harris Hip Score (HHS)] and radiological indicators [including Tonnis classification, ARCO stage, Japanese Investigation Committee (JIC) classification, lateral preserved angle (LPA), anterior preserved angle (APA), and combined preserved angle (CPA)] before and after treatment were compared. Kaplan–Meier survival analysis and Cox regression analysis were used to identify the risk factors associated with femoral head collapse.

Result: Twenty-six males and 18 females with an average age of 38.3 ± 2.8 were followed for an average of 7.95 years. Forty-six of the 66 (69.7%) hips had no progression in pain or collapse, and patients exhibited a higher HHS (p < 0.05) after therapy. Twenty of the 66 (30.3%) hips progressed in Tonnis classification and ARCO stage, but only one of the 66 (1.5%) hips required total hip arthroplasty (THA). The Kaplan–Meier survivorship curve suggested that the survival rates were 96.97% at 5 years, 69.15% at 10 years, and 40.33% at 15 years. Patients with type A necrotic lesions on anteroposterior (AP) and frog-leg lateral (FLL) radiographs revealed 100% survival rates. Multivariate Cox regression analysis revealed that patients with an LPA ≤ 60.9 exhibited a 3.87 times higher risk of collapse of the femoral head [95% confidence interval (CI), 1.241–5.673] than did those patients with an LPA>60.9.

Conclusion: HXTL capsules could be a treatment option for ARCO stage II ONFH, resulting in improved hip function and delayed progression to femoral head collapse, especially when the anterior and lateral portions of the femoral head were not affected. However, an LPA of less than 60.9° may be a risk factor for collapse of the femoral head.

Clinical Trial Registration:http://www.chictr.org.cn/showproj.aspx?proj=10829, identifier ChiCTR-OPC-15007030

Association of MIR17HG and MIR155HG gene variants with steroid-induced osteonecrosis of the femoral head in the population of northern China

Introduction

Steroid-induced osteonecrosis of the femoral head (ONFH) is a disease of the bone. Metabolism and genetic factors are generally considered to play an important role. The purpose of this study was to investigate the relationship between single-nucleotide polymorphisms (SNPs) in MIR17HG and MIR155HG and the risk of steroid-induced ONFH in the population of northern China.

Methods

A total of 199 steroid-induced ONFH patients and 506 healthy controls were recruited for the study. Four SNPs of MIR17HG and seven SNPs of MIR155HG were genotyped by Sequenom MassARRAY. ORs and 95% CIs were used to evaluate the relationship between these SNPs and steroid-induced ONFH.

Results

In the codominant model, patients with the MIR17HG SNPs (rs7318578) AA genotype had an increased risk of steroid-induced ONFH (OR = 1.79, p = 0.039); in the recessive model, patients with the MIR17HG SNP (rs7318578) AA genotype had an increased risk of steroid-induced ONFH (OR = 1.78, p = 0.032). Stratified analysis showed that a MIR17HG SNP (rs7318578) and the MIR155HG SNPs (rs77218221, rs11911469, rs34904192 and rs4143370) were closely related to different unornamented phenotypes of steroid-induced ONFH. Analysis of the clinical indicators revealed significant differences in high-density lipoprotein (HDL-C) levels between the ONFH group and the control group (p = 0.005). In the MIR17HG SNP (rs75267932), patients with different genotypes had different levels of triglyceride (TG). The MIR155HG SNPs (rs77699734, rs1893650, and rs34904192) showed differences in triglyceride (TG), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C) levels in patients with different genotypes.

Conclusion

Our results confirm that MIR17HG and MIR155HG gene mutations are associated with steroid-induced ONFH susceptibility in the population of northern China, providing new evidence for the early detection and prevention of ONFH.

Glucocorticoids induce osteonecrosis of the femoral head through the Hippo signaling pathway

Osteonecrosis of the femoral head (ONFH) induced by glucocorticoids (GCs) has been considered to be associated with the dysfunction of bone marrow mesenchymal stem cells (BMSCs). Studies have reported that GCs can regulate the normal differentiation of BMSCs. However, the exact mechanism of this regulation remains unclear. In this study, we used methylprednisolone (MPS) to induce BMSCs, and then found that the Hippo signaling pathway was upregulated in a dose-dependent manner compared to that in the control group. In addition, the osteogenic ability of BMSCs was decreased, as evaluated by Alizarin Red S staining analysis and alkaline phosphatase activity assays, accompanied by the downregulated expression of Runx2, osteopontin, and osteocalcin. Additionally, the adipogenic capacity of BMSCs under the MPS conditions was increased, as identified by Oil Red O staining with upregulated triglyceride and PPARγ expression. Moreover, suppression by knockdown of MST1 was found to attenuate the Hippo signaling pathway and adipogenic differentiation, while enhancing osteogenic differentiation. In conclusion, our findings revealed that the Hippo signaling pathway was involved in GC-ONFH by affecting the osteogenic and adipogenic differentiation capacities of BMSCs. Our study could provide a basis for further investigation of the specific function of the Hippo pathway in ONFH.

Activation of cannabinoid receptor 2 alleviates glucocorticoid-induced osteonecrosis of femoral head with osteogenesis and maintenance of blood supply

In glucocorticoid (GC)-induced osteonecrosis of the femoral head (ONFH), downregulated osteogenic ability and damaged blood supply are two key pathogenic mechanisms. Studies suggested that cannabinoid receptor 2 (CB2) is expressed in bone tissue and it plays a positive role in osteogenesis. However, whether CB2 could enhance bone formation and blood supply in GC-induced ONFH remains unknown. In this study, we focused on the effect of CB2 in GC-induced ONFH and possible mechanisms in vitro and in vivo. By using GC-induced ONFH rat model, rat-bone mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) to address the interaction of CB2 in vitro and in vivo, we evaluate the osteogenic and angiogenic effect variation and possible mechanisms. Micro-CT, histological staining, angiography, calcein labeling, Alizarin red staining (ARS), alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) staining, TUNEL staining, migration assay, scratch assay, and tube formation were applied in this study. Our results showed that selective activation of CB2 alleviates GC-induced ONFH. The activation of CB2 strengthened the osteogenic activity of BMSCs under the influence of GCs by promotion of GSK-3β/β-catenin signaling pathway. Furthermore, CB2 promoted HUVECs migration and tube-forming capacities. Our findings indicated that CB2 may serve as a rational new treatment strategy against GC-induced ONFH by osteogenesis activation and maintenance of blood supply.

Porous tantalum implant for treatment of early-stage osteonecrosis of the femoral head: a minimum 5-year follow-up study

BACKGROUND

To evaluate the survival rate of porous tantalum rod implantation in the treatment of osteonecrosis of the femoral head (ONFH), evaluate its clinical effect and imaging results.

METHODS

From January 2008 to December 2013, porous tantalum rod implantation for ONFH was performed in two institutions. Statistical analysis of operation data, including operation time, blood loss and blood transfusion were recorded.

RESULTS

52 hips received complete follow-up, the average follow-up time was 85.7 months (60-132 months). 24 hips turned to THA at the end of follow-up (46.2%), the average time was 44.3 ± 32.8 months, and the average Harris hip score before THA was 57.1 ± 7.6. Cox proportional-hazards model revealed that Association Research Circulation Osseous (ARCO) stage (P = 0.017), bone marrow edema (P = 0.006) and age > 40 years (P = 0.043) were independent risk factors for conversion to THA.

CONCLUSION

ARCO stage, age and bone marrow edema were risk factors for the failure of porous tantalum rod implantation to convert to THA.

A Network Pharmacology and Molecular Docking Strategy to Explore Potential Targets and Mechanisms Underlying the Effect of Curcumin on Osteonecrosis of the Femoral Head in Systemic Lupus Erythematosus

Background

Systemic lupus erythematosus (SLE) is a refractory immune disease, which is often complicated with osteonecrosis of the femoral head (ONFH). Curcumin, the most active ingredient of Curcuma longa with a variety of biological activities, has wide effects on the body system. The study is aimed at exploring the potential therapeutic targets underlying the effect of curcumin on SLE-ONFH by utilizing a network pharmacology approach and molecular docking strategy.

Methods

Curcumin and its drug targets were identified using network analysis. First, the Swiss target prediction, GeneCards, and OMIM databases were mined for information relevant to the prediction of curcumin targets and SLE-ONFH-related targets. Second, the curcumin target gene, SLE-ONFH shared gene, and curcumin-SLE-ONFH target gene networks were created in Cytoscape software followed by collecting the candidate targets of each component by R software. Third, the targets and enriched pathways were examined by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Eventually, a gene-pathway network was constructed and visualized by Cytoscape software; key potential central targets were verified and checked by molecular docking and literature review.

Results

201 potential targets of curcumin and 170 related targets involved in SLE-ONFH were subjected to network analysis, and the 36 intersection targets indicated the potential targets of curcumin for the treatment of SLE-ONFH. Additionally, for getting more comprehensive and accurate candidate genes, the 36 potential targets were determined to be analyzed by network topology and 285 candidate genes were obtained finally. The top 20 biological processes, cellular components, and molecular functions were identified, when corrected by a P value ≤ 0.05. 20 related signaling pathways were identified by KEGG analysis, when corrected according to a Bonferroni P value ≤ 0.05. Molecular docking showed that the top three genes (TP53, IL6, VEGFA) have good binding force with curcumin; combined with literature review, some other genes such as TNF, CCND1, CASP3, and MMP9 were also identified.

Conclusion

The present study explored the potential targets and signaling pathways of curcumin against SLE-ONFH, which could provide a better understanding of its effects in terms of regulating cell cycle, angiogenesis, immunosuppression, inflammation, and bone destruction.

[Clinical significance of different imaging manifestations of osteonecrosis of femoral head in the peri-collapse stage]

Objective

To explore the different imaging manifestations of osteonecrosis of the femoral head (ONFH) and their correlation with the occurrence of pain during the peri-collapse period.

Methods

The 372 patients (624 hips) with ONFH in the peri-collapse stage who were admitted between December 2016 and October 2019 and met the selection criteria were selected as the research objects. Among them, there were 270 males and 102 females, with an average age of 35.3 years (mean, 15-65 years). There were 120 cases of unilateral hip and 252 cases of bilateral hips. There were 39 cases (39 hips) of traumatic ONFH, 196 cases (346 hips) of hormonal ONFH, 102 cases (178 hips) of alcoholic ONFH, and 35 cases (61 hips) of idiopathic ONFH. Among them, there were 482 hips with pain symptoms and 142 hips without pain. The pain duration was less than 3 months in 212 hips, 3-6 months in 124 hips, 6-12 months in 117 hips, and more than 12 months in 29 hips. According to the Association Research Circulation Osseous (ARCO) staging, the ONFH was rated as stage Ⅱ in 325 hips and stage Ⅲ in 299 hips. The patients were grouped according to ONFH etiology and ARCO staging, and hip joint pain and X-ray film (crescent sign and cystic changes), CT (subchondral bone fractures and cystic changes), and MRI (bone marrow edema, joint effusion, and subchondral hypointensity zone) were compared. Spearman rank correlation was used to determine the correlation between ONFH pain duration and X-ray film, CT, and MRI imaging manifestations.

Results

There were significant differences ( P<0.05) between ONFH patients with different etiologies in crescent sign on X-ray film, subchondral bone fracture on CT, and joint effusion on MRI. And there were significant differences ( P<0.05) between ONFH patients with different ARCO stages in hip pain duration and all imaging manifestations. Correlation analysis showed that the pain duration of ONFH patients was correlated with all imaging manifestations ( P<0.05). The cystic change on CT was correlated with the subchondral hypointensity zone and joint effusion grade on MRI, and subchondral hypointensity zone and joint effusion grade on MRI were also correlated ( P<0.05).

Conclusion

The cystic changes, subchondral hypointensity zone, and joint effusion are closely related to the collapse of the femoral head and hip pain in patients with ONFH in the peri-collapse stage. The above-mentioned signals in stage Ⅱ ONFH indicate the instability of the femoral head, which is to predict the development of ONFH and the rational choice of hip-preserving treatment methods provides a basis.

Association between LINC-PINT and LINC00599 gene polymorphism and the risk of steroid-induced osteonecrosis of the femoral head in the population of northern China

BACKGROUND

Steroid-induced osteonecrosis of the femoral head (ONFH) is a complex disease affected by genetics. LncRNA LINC-PINT and LINC00599 have been proved to be associated with susceptibility to a variety of diseases, however it is not clear whether they are related to steroid-induced ONFH. Therefore, this study was aimed at investigating the correlation between the polymorphisms of LINC-PINT and LINC00599 genes and steroid-induced ONFH in the population of northern China.

METHODS

A case-control study including 199 patients and 725 controls was designed. The Agena MassARRAY platform was used for the detection of single nucleotide polymorphisms (SNPs) in LINC-PINT and LINC00599 genes. Chi-square test and logistic regression were used to evaluate the association between the above SNPs and steroid-induced ONFH in allelic and genetic models. Besides, one-way ANOVA was used to study the relationship between these SNPs and partial lipid levels.

RESULTS

In the LINC00599 gene, two sites are related to steroid-induced ONFH. Among them, rs2272026 increased the risk of the disease in co-dominant (heterozygous) and dominant models. And rs1962430 is a risk factor for this disease in the allelic, co-dominance (heterozygous), dominant and additive model. whereas in women with steroid-induced ONFH, three sites in the LINC-PINT gene are related to the disease. Thereinto, rs157916 reduces the risk of the disease in allelic, co-dominant (homozygous), recessive and additive models. Rs16873842 is related to the reduced risk of the disease in allele, dominant and additive models. And rs7781295 is a protective factor for steroid-induced ONFH in the allelic and additive model.

CONCLUSION

Our study suggests that the polymorphisms of LINC-PINT and LINC00599 genes are related to the susceptibility of steroid-induced ONFH in Chinese Han population.

Effect of L3MBTL3/PTPN9 polymorphisms on risk to alcohol-induced ONFH in Chinese Han population

PURPOSE

Alcohol-induced osteonecrosis femoral head necrosis (ONFH) is a disease that seriously affects human health. Abnormal expression of L3MBTL3/PTPN9 gene can cause a variety of human diseases. The purpose of this study is to investigate the effect of L3MBTL3/PTPN9 gene polymorphism on the susceptibility of alcohol-induced ONFH in Chinese Han population.

METHODS

A total of 308 alcohol-induced ONFH patients and 425 healthy controls were enrolled in this case-control study. Alleles, genotypes, genetic models, haplotypes, and multifactor dimensionality reduction analyses (MDR) based on age-corrected by using odds ratio (OR) and 95% confidence interval (CI) were performed.

RESULTS

Our result revealed rs2068957 in the L3MBTL3 gene increased the risk of alcohol ONFH under the recessive model after correction. Besides, we also found that rs75393192 in the PTPN9 gene was a protective site in stratification over 40 years of age and stage. In stratified analysis of necrotic sites, we only found that rs2068957 was associated with increased susceptibility of alcohol-induced ONFH under the co-dominant model and recessive model. Haplotype "GC" in the block (rs76107647|rs10851882 in PTPN9 gene) significantly decreased the susceptibility of alcoholic ONFH.

CONCLUSIONS

Our results provide evidence that L3MBTL3/PTPN9 polymorphisms are associated with alcohol-induced ONFH risk in Chinese Han population.

The efficacy of core decompression for steroid-associated osteonecrosis of the femoral head in rabbits

Although core decompression (CD) is often performed in the early stage of osteonecrosis of the femoral head (ONFH), the procedure does not always prevent subsequent deterioration and the effects of CD are not fully clarified. The aim of this study is to evaluate the efficacy of CD for steroid-associated ONFH in rabbits. Twelve male and 12 female New Zealand rabbits were injected intramuscularly 20 mg/kg of methylprednisolone once and were divided into the disease control and CD groups. In the disease control group, rabbits had no treatment and were euthanized at 12 weeks postinjection. In the CD group, rabbits underwent left femoral CD at 4 weeks postinjection and were euthanized 8 weeks postoperatively. The left femurs were collected to perform morphological, biomechanical, and histological analysis. Bone mineral density and bone volume fraction in the femoral head in the CD group were significantly higher than in the disease control group. However, no difference in the mechanical strength was observed between the two groups. Histological analysis showed that alkaline phosphatase and CD31 positive cells significantly increased in the males after CD treatment. The number of empty lacunae in the surrounding trabecular bone was significantly higher in the CD group. The current study indicated that CD improved the morphological properties, but did not improve the mechanical strength in the femoral head at early-stage ONFH. These data suggest the need for additional biological, mechanical strategies, and therapeutic windows to improve the outcome of early-stage steroid-associated ONFH.

Comparison of cell therapy and other novel adjunctive therapies combined with core decompression for the treatment of osteonecrosis of the femoral head : a systematic review and meta-analysis of 20 studies

Aims

The value of core decompression (CD) in the treatment of osteonecrosis of the femoral head (ONFH) remains controversial. We conducted a systematic review and meta-analysis to evaluate whether CD combined with other treatments could improve the clinical and radiological outcomes of ONFH patients compared with CD alone.

Methods

We searched the PubMed, Embase, Web of Science, and Cochrane Library databases until June 2020. All randomized controlled trials (RCTs) and clinical controlled trials (CCTs) comparing CD alone and CD combined with other measures (CD + cell therapy, CD + bone grafting, CD + porous tantalum rod, etc.) for the treatment of ONFH were considered eligible for inclusion. The primary outcomes of interest were Harris Hip Score (HHS), ONFH stage progression, structural failure (collapse) of the femoral head, and conversion to total hip arthroplasty (THA). The pooled data were analyzed using Review Manager 5.3 software.

Results

A total of 20 studies with 2,123 hips were included (CD alone = 768, CD combined with other treatments = 1,355). The combination of CD with other therapeutic interventions resulted in a higher HHS (mean difference (MD) = 6.46, 95% confidence interval (CI) = 2.10 to 10.83, p = 0.004) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (MD = −10.92, 95% CI = -21.41 to -4.03, p = 0.040) and a lower visual analogue scale (VAS) score (MD = −0.99, 95% CI = -1.56 to -0.42, p < 0.001) than CD alone. For the rates of disease stage progression, 91 (20%) progressed in the intervention group compared to 146 (36%) in the control group (odds ratio (OR) = 0.32, 95% CI = 0.16 to 0.64, p = 0.001). In addition, the intervention group had a more significant advantage in delaying femoral head progression to the collapsed stage (OR = 0.32, 95% CI = 0.17 to 0.61, p < 0.001) and reducing the odds of conversion to THA (OR = 0.35, 95% CI = 0.23 to 0.55, p < 0.001) compared to the control group. There were no serious adverse events in either group. Subgroup analysis showed that the addition of cell therapy significantly improved clinical and radiological outcomes compared to CD alone, and this approach appeared to be more effective than other therapies, particularly in precollapse (stage I to II) ONFH patients.

Conclusion

There was marked heterogeneity in the studies. There is a trend towards improved clinical outcomes with the addition of stem cell therapy to CD.

Cite this article: Bone Joint Res 2021;10(7):445–458.

DNA methylation in the OPG/RANK/RANKL pathway is associated with steroid-induced osteonecrosis of the femoral head

BACKGROUND

Dysregulation of the OPG/RANK/RANKL signalling pathway is a key step in the occurrence of steroid-induced osteonecrosis of the femoral head (ONFH). This study aims to understand the degree of methylation of the OPG, RANK, and RANKL genes in steroid-related ONFH.

METHODS

A case-control study was designed, including 50 patients (25 males and 25 females) and 50 matched controls. The European Molecular Biology Open Software Suite (EMBOSS) was used to predict the existence and location of CpG islands in the OPG, RANK, and RANKL genes. The Agena MassARRAY platform was used to detect the methylation status of the above genes in the blood of subjects. The relationship between the methylation level of CpG sites in each gene and steroid-related ONFH was analysed by the chi-square test, logistic regression analysis, and other statistical methods.

RESULTS

In the CpG islands of the OPG, RANK, and RANKL genes in patients with steroid-related ONFH, several CpG sites with high methylation rates and high methylation levels were found. Some hypermethylated CpG sites increase the risk of steroid-related ONFH. In addition, a few hypermethylated CpG sites have predictive value for the early diagnosis of steroid-related ONFH.

CONCLUSION

Methylation of certain sites in the OPG/RANK/RANKL signalling pathway increases the risk of steroid-related ONFH. Some hypermethylated CpG sites may be used as early prediction and diagnostic targets for steroid-related ONFH.

Relationship between hip joint medial space ratio and collapse of femoral head in non-traumatic osteonecrosis: a retrospective study

To retrospectively analyze the medial space ratio (MSR) of the hip joint to evaluate its efficacy in predicting osteonecrosis of femoral head (ONFH)-induced collapse and its impacts on the mechanical environment of necrotic femoral head. In this retrospective analysis of traditional Chinese medicine, non-traumatic ONFH (NONFH) patients from January 2008 to December 2013 were selected. The patients were divided into collapse group and non-collapse group based on whether the femoral head collapsed. The anatomical parameters including center–edge (CE) angle, sharp angle, acetabular depth ratio and MSR were evaluated. Receiver operating characteristic curves were estimated to evaluate the sensitivity and specificity of MSR and CE angle in collapse prediction. The results showed that 135 patients (151 hips) were included in this study. The differences in CE angle and MSR between collapse group and non-collapse group were statistically significant. The mean survival time of the hips of patients with MSR &lt;20.35 was greater (P &lt; 0.001) than that of patients with MSR &gt;20.35. The ONFH patients with MSR &gt;20.35 were prone to stress concentration. We could conclude that the hip joint MSR and CE angle strongly correlated with the collapse of NONFH. The specificity of MSR is higher than that of CE angle. When MSR is &gt;20.35, the collapse rate of ONFH will increase significantly.

Early Rehabilitation and Periprosthetic Bone Environment after Primary Total Hip Arthroplasty: A Randomized Controlled Trial

Objective

To investigate whether the periprosthetic bone environment could be affected by activity during the early rehabilitation period after primary total hip arthroplasty (THA) and to evaluate the safety and efficacy of activity during the early rehabilitation period.

Methods

This random clinical trial was conducted from January 2017 to July 2017. A total of 22 selected patients with advanced osteonecrosis of the femoral head (ONFH) who underwent primary unilateral THA were randomized (1:1) to a high activity level group (HA group) or a low activity level group (LA group). The HA group included nine men and two women, aged 53.18 ± 13.29 years. The LA group included five men and six women, aged 55.73 ± 11.73 years. The intervention was different postoperative daily walking distances guided by researchers: 1727.27 ± 564.08 m 0–2 months and 4272.73 ± 904.53 m 3–6 months postoperation for the HA group and 909.09 ± 583.87 m 0–2 months and 2409.09 ± 1068.13 m 3–6 months postoperation for LA group. The primary outcomes were radiographic evaluation (prosthetic stability and stress shielding based on the Engh scale) and bone mineral density (BMD) with a femoral prosthesis (individual and intergroup comparison using seven Gruen zones) at 6 months postoperatively. Secondary outcomes were set to confirm the safety and efficacy of activity during early rehabilitation, including day 1 erythrocyte sedimentation rate (ESR), day 1 hypersensitive C‐reactive protein (CRP), length of hospital stay (LOS), and the Harris hip score (HHS) at discharge, 2 months postoperatively, and 6 months postoperatively.

Results

Patients were followed up for 6 months after surgery. Regarding primary outcomes, all prostheses were assessed as stable, with bone in‐growth. There were no adverse events in any cases. The HA group had a higher incidence of stress shielding than the LA group, but there was no statistical significance (63.64% vs 18.18%; P > 0.05). The degree of stress shielding had a different distribution for the two groups (P < 0.05). In the HA group and the LA group, the median percentage difference of the BMD on the operated side was −25% and was −13% in Zone 1, −8% and − 1% in Zone 2, +1% and 3% in Zone 3, +6% and + 6% in Zone 4, −2% and +2% in Zone 5, −3% and −1% in Zone 6, and −24% and −12% in Zone 7 compared with the unoperated side. The BMD was significantly reduced in the medial proximal femur (Zone 1) and the lateral proximal femur (Zone 7) in both groups (P < 0.05). Furthermore, it was increased in the distal femur (Zone 4) in the HA group (P < 0.05). No difference was found in the BMD when comparing between groups. Regarding secondary outcomes, there was no statistical difference in day 1 ESR and day 1 CPR. The average LOS was similar in the HA and LA groups (7.00 days vs 7.18 days, P > 0.05). The HHS on day of discharge was higher in the HA group than in the LA group (60.73 ± 5.37 points vs 51.18 ± 8.05 points, P < 0.05); however, no statistically significant difference was found in postoperative the HHS at 2 months (81.73 ± 6.92 points vs 78.36 ± 9.18 points, P > 0.05) and 6 months (90.45 ± 5.24 points vs 91.55 ± 4.03 points, P > 0.05).

Conclusion

High activity levels during early rehabilitation after primary THA accelerate the process of bone remodeling and aggravate stress shielding, with no significant benefits for functional recovery.

Attenuated serum vasoactive intestinal peptide concentrations are correlated with disease severity of non-traumatic osteonecrosis of femoral head

Background and objective

The neuropeptide vasoactive intestinal peptide is a 28-amino acid neuropeptide that has been shown to stimulate bone repair and angiogenesis. The purpose of this study was to explore the potential role of serum VIP concentration in osteonecrosis of femoral trauma (ONFH).

Methods

One hundred five patients diagnosed with non-traumatic ONFH and 103 healthy individuals were enrolled in our study. Serum VIP, tumor necrosis factor-α (TNF-α), interluekin-1 beta (IL-1β), and macrophage colony-stimulating factor (M-CSF) levels also were detected using the commercial ELISA kit. Radiographic progression was evaluated using FICAT classification. The clinical severity of ONFH was assessed by visual analog score (VAS) and Harris Hip Score (HHS). Receiver-operating characteristic (ROC) curve was performed to test the potential diagnostic value of VIP in radiographic progression.

Results

The serum VIP level of patients with non-traumatic ONFH was significantly lower than that of healthy controls. There was no significant difference between the alcohol group, the steroid-induction group, and the idiopathic group. Serum VIP levels were significantly higher in ONFH patients with femoral head pre-collapse stage than collapse stage. Serum VIP levels were significantly lower. FICAT 4 non-traumatic ONFH patients had significantly lower serum concentrations of VIP when compared with FICAT 3 and FICAT 2. Moreover, serum VIP levels were significantly lower in ONFH patients with FICAT 3 than FICAT 2. Serum VIP levels were negatively related to FICAT stage. In addition, serum VIP levels were negatively associated with VAS score and positively associated with HHS score. Last, we found serum VIP levels were negatively associated with serum TNF-α and IL-1β levels. ROC curve analysis indicated that decreased serum VIP could serve as a decent biomarker with regard to the diagnosis of radiographic progression.

Conclusion

Attenuated serum VIP concentrations are correlated with disease severity of non-traumatic ONFH. Decreased serum VIP may serve as a potential indicator of non-traumatic ONFH.