Factor V Leiden and Prothrombin Gene Mutation: Risk Factors for Osteonecrosis of the Femoral Head in Adults

Updating Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH), a condition characterized by the presence of a necrotic bone lesion in the femoral head, is caused by a disruption in the blood supply. Its occurrence is more common in young and middle-aged adults and it is the main reason for performance of total hip arthroplasty in this age group. Its incidence is increasing along with increased use of glucocorticoids for management of adjuvant therapy for treatment of leukemia as well as organ transplantation and other myelogenous diseases. Current information on etiology and pathogenesis, as well as natural history, stage system, and treatments is provided in this review. A description of the Association Research Circulation Osseous (ARCO) criteria for classification of glucocorticoids- and alcohol-associated ONFH, 2019 ARCO staging system, and 2021 ARCO classification using computed tomography for the early stages of ONFH is also provided.

Germline VWF/MPRIP and somatoplasm FGA variants synergically confer susceptibility to non-traumatic osteonecrosis of the femoral head

Non-traumatic osteonecrosis of the femoral head (ONFH) relies on multiple pathogenic factors, including intravascular coagulation, osteoporosis and lipid metabolism disorders. Despite extensively explored from various aspects, genetic mechanism underlying non-traumatic ONFH has not been fully elucidated. We randomly collected blood and necrotic tissue samples from 32 patients with non-traumatic ONFH as well as blood samples from 30 healthy individuals for whole exome sequencing (WES). Germline mutation and somatic mutation were analyzed to identify new potential pathogenic genes responsible for non-traumatic ONFH. Three genes might correlate with non-traumatic ONFH: VWF, MPRIP (germline mutations) and FGA (somatic mutations). Germline or somatic mutations in VWF, MPRIP and FGA correlate with intravascular coagulation, thrombosis, and consequently, ischemic necrosis of the femoral head.

Osteochondritis dissecans of the metacarpal head in a soldier treated with osteochondral autograft transplantation surgery: A case report

RATIONALE

Osteochondral autograft transplantation surgery (OATS) was introduced as a treatment for hand osteochondritis dissecans (OCD), and successful results were reported. However, the cartilage height of the donor plug has not yet been established compared with that of other joints. We present a case using OATS for OCD of the 3rd metacarpal (MCP) head that occurred in a soldier and the findings of magnetic resonance imaging (MRI) images taken at 12 weeks after surgery.

PATIENT CONCERNS

A 21-year-old male presented with a painful, swollen 3rd MCP joint in the right hand. He was a soldier and right-handed; in addition, he did not recall any traumatic events, nor had he taken any corticosteroid medications before. The patient was excluded from military training and underwent conservative treatment with medication and a brace in a military hospital for 3 months.

DIAGNOSIS

The patient was diagnosed with OCD due to avascular necrosis of the 3rd MCP head of the right hand through X-ray and MRI.

INTERVENTIONS

OATS was planned as a surgical treatment. Surgery uncovered a 10 × 10 mm2, isolated cartilage defect of the 3rd MCP head that had an irregular margin and a loose body. Using Arthrex OATS, a 10-mm diameter, 10-mm depth hole was made at the articular defect site, and an 11-mm diameter, 12-length plug was harvested from the left lateral femoral condyle. The donor plug was inserted into the prepared defect site with press-fit fixation.

OUTCOMES

At the last follow-up, the height of the articular cartilage had subsided with union on MRI 12 weeks after the surgery. However, the patient was asymptomatic with a normal range of motion of the right hand, and he returned to military training.

LESSONS

Although the joints of the hand are small and non-weight bearing, the level of articular cartilage of the donor plug was subsided in a follow-up MRI in our case. We suggest that the difference in cartilage thickness between the donor and the recipient might have been the cause of subsidence of the articular cartilage, and therefore, it may be helpful to transplant donors with similar thicknesses of articular cartilage.

Prothrombin Time and Coagulation Factor IX as Hemostatic Risk Markers for Legg- Calvé-Perthes Disease

BACKGROUND

Legg-Calvé-Perthes disease (LCPD) is a pediatric disorder that occurs due to the avascular necrosis of the femoral head and affects the range of motion of the hip in various degrees. Its etiology is still unknown, although it has been associated with coagulation abnormalities, however, the lack of reproducibility in the results in various studies has created a controversy as to whether hemostasis disorders are related to LCPD. On the other hand, there is little information on laboratory studies that could facilitate the diagnosis and treatment of LCPD.

METHODS

Blood and plasma samples were tested from 25 patients with LCPD and 50 healthy controls, matched by sex and age. Cellular markers were evaluated through complete blood count, as well as coagulation times, coagulation factors activity, antithrombotic proteins, and homocysteine concentration.

RESULTS

After assessing activity value frequencies in each group, the results showed more significant activity in some of the biological risk markers of thrombophilia, presenting a substantial difference in prothrombin time↘, FV↗, FVIII↗, FIX↗, and Hcy↗. These values imply that there may be hypercoagulable states in patients, which can cause thrombotic events.

CONCLUSIONS

Diminished prothrombin time and increase in FV activity, FVIII, FIX, and Hcy concentration support the hypothesis that microthrombi formation in small-caliber vessels could be causing avascularity and femoral necrosis, which are traits of LCPD. In addition, based on our results, we believe that the laboratory studies carried out are very useful in the diagnosis and treatment of LCPD.

Familial Thrombophilia Is Associated With Primary Multifocal Osteonecrosis: A Case-Control Study of 40 Patients

To characterize pathoetiologic associations of heritable thrombophilia-hypofibrinolysis with idiopathic (primary) multifocal osteonecrosis (ON) (≥3 ON anatomic sites), we prospectively studied 28 women and 12 men with primary multifocal ON compared with 27 women and 24 men with primary nonmultifocal ON (<3 sites) and 110 healthy controls without ON. The 40 cases with primary multifocal ON differed from controls for 3 familial thrombophilias: Factor V Leiden heterozygosity (6 of 40 [15%] vs 2 of 109 [2%], P=.002), G20210A prothrombin gene heterozygosity (6 of 40 [15%] vs 3 of 110 [3%], P=.011), and high (>150%) Factor VIII (8 of 40 [20%] vs 7 of 103 [7%], P=.031). These case-control familial coagulation differences paralleled those in 51 concurrently evaluated cases with primary nonmulti-focal ON, 7 of 51 (14%) of whom had Factor V Leiden heterozygosity vs 2% of controls (P=.005) and 14 of 44 (32%) of whom had high Factor VIII vs 7 of 103 (7%) of controls (P=.0002). Recognition of familial thrombophilia as a common pathoetiology of primary multifocal ON provides an opportunity for early anticoagulation (before joint collapse), allowing both prophylaxis and therapy aimed at relieving pain and slowing or stopping progression of the disease to joint collapse. [Orthopedics. 202X;XX(X):xx-xx.].

Atraumatic osteonecrosis of the humeral head: pathophysiology and current concepts of evaluation and treatment

The humeral head is considered the second most common site for osteonecrosis to occur after the femoral head. As seen in the femoral head, the circulatory implications characteristic of this condition are attributable to the interaction between a genetic predisposition and the exposure to certain risk factors. There is no consensus regarding the pathogenesis of osteonecrosis, yet the final common pathway results in disrupted blood supply, increased intraosseous pressure, and bone death. Disease staging using radiography and magnetic resonance imaging is predictive of disease progression and can help the orthopedic surgeon to guide treatment. Although there is a myriad of treatment modalities, there is a lack of high-quality evidence to conclude what is the most appropriate treatment option for each stage of humeral head osteonecrosis. Nonoperative treatment is the preferred option in early-stage disease, and it may prevent disease progression. Nonetheless, in some cases, disease progression occurs despite nonoperative measures, and surgical treatment is required. The purpose of this article is to provide an updated review of the available evidence on risk factors, diagnosis, and treatment of atraumatic humeral head osteonecrosis.

Integrative analyses of genes related to femoral head osteonecrosis: an umbrella review of systematic reviews and meta-analyses of observational studies

Background

Femoral head osteonecrosis (FHON) is a worldwide challenging clinical topic. Steroid use is one of the main etiologies of FHON. There are several genetic variants associated with FHON. Therefore, the purpose of this umbrella review was to provide a comprehensive summary of a meta-analysis and systematic review of genetic variations associated with nonsteroidal and steroid-induced FHON.

Methods

The eligible studies were selected from the PubMed and MEDLINE databases for the collection of diverse systematic meta-analyses and reviews. The genetic main effect score was assigned using the Human Genome Epidemiology Network’s Venice criteria to assess the cumulative evidence on the effects of a single nucleotide polymorphism (SNP) on FHON.

Results

Eight articles reported the meta-analysis of candidate SNP-based studies covering eight genes and 13 genetic variants. In the nonsteroid-induced FHON genetic variants including rs2012390 and rs11225394 in MMP8, rs1800629 and rs361525 in tumor necrosis factor (TNF)-α, VNTR in intron 4, rs1799983 and rs2070744 in endothelial nitric oxide synthase (eNOS), rs2010963 in vascular endothelial growth factor (VEGF), and rs6025 in factor V showed significance in each reference. The steroid-induced FHON genetic variants including rs693 and rs1042031 in apolipoprotein (Apo)B, rs1045642 in ABCB1, and rs1799889 in PAI-1 showed significance in each reference.

Conclusion

Based on the systematic review conducted in this study, we organized the genomes associated with FHON and looked at each contribution. Our results could give an integrative approach for understanding the mechanism of FHON etiology. It is expected that these results could contribute to the strategy of prediagnosis, evaluating the individual risk of nonsteroid-induced and steroid-induced FHON.

Level of Evidence: Level I.

Osteonecrosis of the Jaws in Patients with Hereditary Thrombophilia/Hypofibrinolysis-From Pathophysiology to Therapeutic Implications

Osteonecrosis of the jaws (ONJ) usually has a clear etiology. Local infection or trauma, radiotherapy and drugs that disrupt the vascular supply or bone turnover in the jaws are its major contributors. The thrombotic occlusion of the bone’s venous outflow that occurs in individuals with hereditary thrombophilia and/or hypofibrinolysis has a less known impact on jaw health and healing capability. Our research provides the most comprehensive, up-to-date and systematized information on the prevalence and significance of hereditary thrombophilia and/or hypofibrinolysis states in ONJ. We found that hereditary prothrombotic abnormalities are common in patients with ONJ refractory to conventional medical and dental treatments. Thrombophilia traits usually coexist with hypofibrinolysis traits. We also found that frequently acquired prothrombotic abnormalities coexist with hereditary ones and enhance their negative effect on the bone. Therefore, we recommend a personalized therapeutic approach that addresses, in particular, the modifiable risk factors of ONJ. Patients will have clear benefits, as they will be relieved of persistent pain and repeated dental procedures.

Macrophage Activation Led Acute Heart Failure Managed Successfully with Immunosuppression

Macrophage activation leading to multi-organ dysfunction/failure has been described in various hematologic disorders like hemophagocytic lympho-histiocytosis (HLH), also known as macrophage activation syndrome (MAS) and macrophage activation like syndrome (MALS). Congestive heart failure (CHF) appears to be an uncommon manifestation of macrophage activation. This novel entity of macrophage activation-associated cytokine-mediated CHF has not been well reported in the medical literature. We report two young female patients with acute CHF secondary to macrophage activation-associated cytokine storm. An extensive diagnostic workup was negative for other etiologies, such as ischemia, myocarditis, or infections. Their clinical, laboratory, and pathologic findings did not meet the diagnostic criteria for hemophagocytic syndrome (HPS)/MAS. However, both had laboratory and pathologic findings which were consistent with macrophage activation and cytokine storm. One patient met criteria for MALS. Therapeutically, our patients were promptly treated with steroids with or without anti-cytokine therapy with rapid restoration of cardiac function. Macrophage activation-induced disease may not always fulfil the diagnostic criteria for the currently known macrophage activation disorders. We suggest that markers of macrophage activation and cytokine levels should be part of the diagnostic workup in patients with otherwise unexplained acute CHF. Additional research is warranted to further elucidate the underlying mechanism of this disorder.

ARG2, MAP4K5 and TSTA3 as Diagnostic Markers of Steroid-Induced Osteonecrosis of the Femoral Head and Their Correlation With Immune Infiltration

Background

The diagnosis for steroid-induced osteonecrosis of the femoral head (SONFH) is hard to achieve at the early stage, which results in patients receiving ineffective treatment options and a poor prognosis for most cases. The present study aimed to find potential diagnostic markers of SONFH and analyze the effect exerted by infiltration of immune cells in this pathology.

Materials and Methods

R software was adopted for identifying differentially expressed genes (DEGs) and conducting functional investigation based on the microarray dataset. Then we combined SVM-RFE, WGCNA, LASSO logistic regression, and random forest (RF) algorithms for screening the diagnostic markers of SONFH and further verification by qRT-PCR. The diagnostic values were assessed through receiver operating characteristic (ROC) curves. CIBERSORT was then adopted for assessing the infiltration of immune cells and the relationship of infiltration-related immune cells and diagnostic markers.

Results

We identified 383 DEGs overall. This study found ARG2, MAP4K5, and TSTA3 (AUC = 0.980) to be diagnostic markers of SONFH. The results of qRT-PCR showed a statistically significant difference in all markers. Analysis of infiltration of immune cells indicated that neutrophils, activated dendritic cells and memory B cells were likely to show the relationship with SONFH occurrence and progress. Additionally, all diagnostic markers had different degrees of correlation with T cell follicular helper, neutrophils, memory B cells, and activated dendritic cells.

Conclusion

ARG2, MAP4K5, and TSTA3 are potential diagnostic genes for SONFH, and infiltration of immune cells may critically impact SONFH occurrence and progression.

Osteonecrosis of the Femoral Head in Patients with Hypercoagulability-From Pathophysiology to Therapeutic Implications

Osteonecrosis of the femoral head (ONFH) is a debilitating disease with major social and economic impacts. It frequently affects relatively young adults and has a predilection for rapid progression to femoral head collapse and end-stage hip arthritis. If not diagnosed and treated properly in the early stages, ONFH has devastating consequences and leads to mandatory total hip arthroplasty. The pathophysiology of non-traumatic ONFH is very complex and not fully understood. While multiple risk factors have been associated with secondary ONFH, there are still many cases in which a clear etiology cannot be established. Recognition of the prothrombotic state as part of the etiopathogeny of primary ONFH provides an opportunity for early medical intervention, with implications for both prophylaxis and therapy aimed at slowing or stopping the progression of the disease. Hereditary thrombophilia and hypofibrinolysis are associated with thrombotic occlusion of bone vessels. Anticoagulant treatment can change the natural course of the disease and improve patients' quality of life. The present work focused on highlighting the association between hereditary thrombophilia/hypofibrinolysis states and ONFH, emphasizing the importance of identifying this condition. We have also provided strong arguments to support the efficiency and safety of anticoagulant treatment in the early stages of the disease, encouraging etiological diagnosis and prompt therapeutic intervention. In the era of direct oral anticoagulants, new therapeutic options have become available, enabling better long-term compliance.

Osteonecrosis of the Femoral Head: an Updated Review of ARCO on Pathogenesis, Staging and Treatment

Non-traumatic osteonecrosis of the femoral head (ONFH) usually affects adults younger than 50 years and frequently leads to femoral head collapse and subsequent arthritis of the hip. It is becoming more prevalent along with increasing use of corticosteroids for the adjuvant therapy of leukemia and other myelogenous diseases as well as management of organ transplantation. This review updated knowledge on the pathogenesis, classification criteria, staging system, and treatment of ONFH.

Autologous stem cell implantation with core decompression for avascular necrosis of the femoral head using a new device

INTRODUCTION

Autologous stem cell progenitor implantation into necrotic lesions of the femoral head has previously been described as a potential treatment for avascular necrosis (AVN), on the basis that there is a reduced number of functioning stem cells in the marrow within the necrotic segment. We present a case series of patients with AVN that underwent core decompression with autologous stem cell implantation using a new device.

METHODS

The records and imaging of patients with AVN of the femoral head treated by a single surgeon were retrospectively reviewed. All patients were treated with core decompression and stem cell progenitor implantation, using the PerFuse system. Preoperatively, demographic information, AVN staging (as per Ficat and Arlet classification) and visual analogue pain scores (VAS) of the hips were recorded. These results were compared with postoperative VAS and imaging, with further review on the progression of AVN.

RESULTS

We treated 14 hips in 13 patients with an average follow up of 12 months. Patients with Ficat I-II were selected for the procedure. The average preoperative VAS was 3.9. Postoperatively, this dropped to 2.6, with over half of patients reporting at least a two-point decrease in pain. Eight of the 14 treated hips showed no radiological progression of the disease, while six showed femoral head collapse requiring total hip arthroplasty (THA) at an average of ten months after treatment.

CONCLUSION

Our early findings indicate that hip decompression with stem cell progenitor implantation for AVN of the femoral head provides symptomatic relief and may be beneficial in arresting progression of disease using this simple new device.

ARCO Consensus on the Pathogenesis of Non-traumatic Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) is a devastating disease frequently leading to femoral head collapse and hip arthritis. Specifically, non-traumatic ONFH primarily affects young and middle-aged adults. Although compromised local circulation of the femoral head seems to be pathognomonic for the disease, the pathogenesis is perplexing and continues to be an area of scrutiny and research. Comprehension of the pathogenesis is of crucial importance for developing and guiding treatments for the disease. Therefore, we provide an up-to-date consensus on the pathogenesis of non-traumatic ONFH.

Association of Thrombophilic Factors in Pathogenesis of Osteonecrosis of Femoral Head in Indian Population

PURPOSE

Role of heritable blood clotting disorders, both thrombophilias and hypofibrinolysis in causing avascular necrosis (AVN) of femoral head have been studied in regions like Europe and U.S.A. This study was done to investigate the role of heritable thrombophilias in ethnic Indian population.

MATERIALS AND METHODS

A case control study of 150 patients (100 cases and 50 age and sex matched controls) of Indian Ethnicity with clinico-radiographically documented idiopathic AVN of femoral head was done after ethics committee approval. DNA was extracted from the blood and PCR analysis was used to study heritable thrombophilic gene mutation (G1691A Factor V Leiden). Enzyme-linked immunosorbent assay (ELISA)-based assays, were utilized to measure antigen levels of protein C, antithrombin III levels and protein S.

RESULTS

Nine cases out of 100 showed deficiency of Protein C (9%) while no control showed deficiency of Protein C (p value: 0.028-significant, Odds ratio: 9.791) Ten cases showed deficiency of Protein S (10%) in study population as compared to one case (2%) in control population (p value: 0.038-significant, Odds ratio: 5.44). ATIII deficiency was more prevalent in control group i.e. 22% compared to 11% in study group. Factor V mutation was present in 3% cases as compared to one (2%) in control group. (p value is 0.393-not significant).

CONCLUSION

Difference in thrombophilic mutations in various populations indicates possible effect of ethnicity on genetic profile in the development of AVN. This risk stratification will enable in near future early diagnosis and possible role of antithrombotics in disease prevention.

Long-term Anticoagulation Prevents Progression of Stages I and II Primary Osteonecrosis of the Hip in Patients With Familial Thrombophilia

The authors prospectively assessed long-term anticoagulation outcomes (≥3 years) for 9 patients meeting 4 inclusion criteria: pretreatment Ficat stage I or II primary hip osteonecrosis (ON), factor V Leiden or prothrombin G20210A heterozygosity, no contraindication to anticoagulation, and 90-day participation in an initial enoxaparin 60 mg/d protocol. The primary endpoint was prevention of hip collapse (Ficat stage III or IV). The secondary endpoint was pain relief. After 90 days of enoxaparin 60 mg/d, anticoagulation was continued for 8 patients: 4 receiving warfarin (international normalized ratio targeted to 2 to 2.5; 11.5, 13, 14.5, and 21 years), 1 receiving enoxaparin 120 mg/d (11.5 years), and 3 receiving novel oral anticoagulants (5, 6, and 8 years). Radiographs were obtained before treatment; at 3 to 4, 6 to 8, and 12 to 14 months; and then annually. By selection, 8 patients had factor V Leiden heterozygosity and 1 had prothrombin G202010A heterozygosity. Of their 13 hips (Ficat I or II at entry), 12 remained Ficat I or II after 12±5 years (range, 5.5-21 years) of continuous anticoagulation and follow-up; 1 hip radiographically normalized. None of the 13 hips progressed to collapse (Ficat III or IV). Six patients became symptom free after the first 3 months of receiving enoxaparin, 1 after 6 months of anticoagulation, and 1 after 10 months of anticoagulation; all 8 patients remained symptom free with anticoagulation. Anticoagulation for primary hip ON before hip collapse in patients with familial thrombophilia may change the natural history of ON because most untreated patients with ON have joint collapse and total joint replacement within 2 years of original symptoms. [Orthopedics. 2020;43(4):e208-e214.].

Correlational analysis between neutrophil granulocyte levels and osteonecrosis of the femoral head

Background

The correlation between peripheral blood neutrophil level and osteonecrosis of the femoral head (ONFH) has not been extensively studied. Thus, we aimed to investigate the correlation between neutrophil level in the peripheral blood (neutrophil granulocyte) and ONFH.

Methods

A total of 984 cases of ONFH and femoral neck fractures (non-ONFH) diagnosed at the Department of Orthopedics at our institution between January 1, 2011 and December 31, 2016 were retrospectively reviewed. The ONFH and non-ONFH groups comprised 488 and 496 cases, respectively. Basic information and peripheral blood cell levels of the two groups were compared.

Results

The patients’ mean age was 59.89 ± 17.06 years (range: 38–82 years). There were 457 male and 527 female patients, with a male-to-female ratio of 1:1.15. We found that neutrophil granulocyte levels and percentage of neutrophil granulocytes were significantly different between the ONFH and non-ONFH groups. Multimodal regression analysis showed that the percentage of neutrophil granulocytes was an independent protective factor against ONFH.

Conclusions

The factors influencing ONFH are neutrophil granulocyte levels and percentage of neutrophil granulocytes. Percentage of neutrophil granulocytes has a significant correlation with aseptic femoral head necrosis, providing a new perspective and direction for further study of femoral head necrosis.

Efficacy of artificial femoral head replacement for femoral head avascular necrosis

BACKGROUND

Femoral head avascular necrosis (FHAN) is one of the most common progressive orthopedic disorders. Previous studies have reported that artificial femoral head replacement (AFHR) can effectively treat patients with FHAN. However, no systematic review has investigated the efficacy of AFHR for FHAN. This study will assess the efficacy of AFHR for patients with FHAN.

METHODS

We will search MEDLINE, EMBASE, Web of Science, Cochrane Library, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure up to March 1, 2019 without any restrictions. Any randomized controlled trials for assessing the efficacy of AFHR for patients with FHAN. The methodological quality for each eligible study will be assessed by using Cochrane risk of bias tool. Statistical analysis will be conducted by using RevMan 5.3.

RESULTS

This study will provide current evidence of AFHR for patients with FHAN from several aspects, including pain intensity, function, and limitation of femoral head, health-related quality of life, and safety.

CONCLUSION

This study will provide latest evidence on assessing the efficacy and safety of AFHR for FHAN.PROSPERO registration number: PROSPERO CRD42019126249.

Long-term direct oral anticoagulation in primary osteonecrosis with elevated plasminogen activation inhibitor

Osteonecrosis is a pathological condition that could lead to a debilitating physical disease and impede daily activities. It is generally categorised into aetiology - primary (idiopathic) or secondary. When direct damage to the bone vasculature or direct injury of the bone marrow is related to an identifiable cause such as traumatic injuries, steroid or bisphosphonate use, increased alcohol intake, sickle cell disease, autoimmune diseases, chemotherapy or malignancy, it is categorised as secondary osteonecrosis. On the other hand, osteonecrosis wherein the mechanisms of development are not fully understood is categorised as primary or idiopathic osteonecrosis. This category includes inherited thrombophilia and hypofibrinolysis as potential causes. There are no clear guidelines or general agreements about anticoagulation treatment and duration in primary osteonecrosis due to thrombophilia or hypofibrinolysis. We report a case of primary osteonecrosis associated with hypofibrinolysis and successful control with lifelong direct oral anticoagulation therapy.

Impact of IL1R1 and IL1R2 gene polymorphisms on risk of osteonecrosis of the femoral head from a case-control study

Aim

Osteonecrosis of the femoral head (ONFH) refers to bony changes caused by osteocyte death under the effects of complicated factors, which is caused by genetic factors and certain risk factors. Our study aimed to explore whether IL1R1/IL1R2 polymorphisms influenced ONFH risk in the Chinese Han population.

Methods

We selected 286 patients and 441 controls, with 11 single‐nucleotide polymorphisms in IL1R1 and IL1R2 gene were successfully genotyped, and evaluated the associations using the chi‐squared test, Fisher's exact test, T test, and genetic model analyses. Odds ratios and 95% confidence intervals (CIs) were calculated using unconditional logistic regression.

Results

In the allele model, rs11674595 in IL1R2 was associated with increasing the risk of ONFH, the rs10490571 and rs3917225 in IL1R1 gene were associated with an increased risk of ONFH, respectively. In the genetic model, the rs11674595 in IL1R2 gene was associated with an increased risk of ONFH in the codominant model, dominant model, and log‐additive model, respectively. The rs10490571 and rs3917225 in IL1R1 gene conferred an increased risk of ONFH in the codominant model, dominant model, and log‐additive model, respectively. We found none of the haplotypes in the IL1R2 gene was significantly associated with theONFH risk.

Conclusion

Our findings have demonstrated that the rs11674595 (IL1R2), rs10490571, and rs3917225 (IL1R1) were significantly associated with increasing the ONFH risk in the Chinese Han population.

The relationship between apolipoprotein genes polymorphisms and susceptibility to osteonecrosis of the femoral head: a meta-analysis

Background

The objective of this study was to evaluate whether apolipoprotein gene polymorphisms confer susceptibility to osteonecrosis of the femoral head (ONFH).

Methods

The relevant literature was screened from databases of Pubmed, Embase, Wanfang, Weipu and China National Knowledge Internet (CNKI) until May, 2017. In addition, odds ratio (OR) and its corresponding 95% confidence interval (CI) were used as a measure of effect size for calculating effect size.

Results

Totally, six case-control studies were included in this meta-analysis. It revealed that ApoB-C7623T polymorphism frequency was increased in ONFH group than in control group under three genetic models, including allele model (T vs. C, OR = 4.5149, 95% CI: 1.6968–12.0134); additive model (TC vs. CC, OR = 6.2515, 95% CI: 2.0939–18.6640); and dominant model (TT + TC vs. CC, OR = 5.4998, 95% CI: 1.9246–15.7163). In addition, the increased risk of ONFH were related to ApoA1-rs1799837 polymorphism under additive model (AA vs. GG, OR = 1.4175, 95% CI: 1.0522–1.9096) and recessive model (AA vs. GG + AG, OR = 1.7727, 95% CI: 1.3399–2.3452). However, four ApoB rs1042031, rs693, 3’-VNTR and G12619A polymorphisms under the all genetic models were not associated with susceptibility to ONFH.

Conclusion

The T allele and TC genotype of ApoB-C7623T and AA genotype of ApoA1-rs1799837 may contribute to increase the risk of ONFH.

MicroRNA-mediated interacting circuits predict hypoxia and inhibited osteogenesis of stem cells, and dysregulated angiogenesis are involved in osteonecrosis of the femoral head

PURPOSE

MicroRNAs (miRNAs) are associated with various pathologic conditions and can serve as diagnostic or therapeutic biomarkers. This study tried to identify the differentially expressed miRNAs to predict the possible pathomechanisms involved in osteonecrosis of the femoral head (ONFH).

METHODS

We compared the peripheral blood miRNAs in 46 patients with ONFH and 85 healthy controls by microarray and droplet digital polymerase chain reaction (ddPCR). Putative interacted networks between the differentially responded miRNAs were analyzed by web-based bioinformatics prediction tools.

RESULTS

Microarray identified 51 differentially expressed miRNAs with at least twofold change (upregulation in 34 and downregulation in 17), and the results were validated by ddPCR using six selected miRNAs. Bioinformatics genetic network analysis focusing on the six miRNAs found the upregulated miR-18a and miR-19a are associated with angiogenesis after induction of ischemia; the upregulated miR-138-1 can inhibit osteogenic differentiation of mesenchymal stem cells; the most targeted genes, p53 and SERBP1, are associated with hypoxia and hypofibrinolysis.

CONCLUSIONS

This study combined the miRNA analysis with the bioinformatics and predicts that hypoxia, inhibited osteogenesis of stem cells, and dysregulated angiogenesis might be orchestrated through the miRNA interacting circuits in the pathogenesis of ONFH.

Autologous stem cell implantation with core decompression for avascular necrosis of the femoral head

OBJECTIVE

Avascular necrosis (AVN) of the femoral head is a painful, progressive disease that can lead to limited mobility and early hip replacement. Autologous stem cell implantation into the necrotic lesion of the femoral head has been described, on the basis that patients with AVN have a reduced number of stem cells in the marrow. In this study, we aim to describe our technique for decompression of the hip with autologous implantation of stem cells for AVN of the femoral head, as well as retrospectively analyze our results.

METHODS

The records and imaging of patients with avascular necrosis of the femoral head treated by a single surgeon were retrospectively reviewed. All patients were treated with the combination of core decompression with autologous stem cell implantation from the iliac crest. Preoperatively, demographic information, stage of AVN per Association Research Circulation Osseous (ARCO) classification on magnetic resonance imaging and radiograph, and visual analogue pain scores (VAS) of the hip were recorded. Postoperatively, VAS were recorded and imaging was reviewed for progression of AVN or evidence of femoral head collapse. Statistical analysis was conducted comparing pre and postoperative VAS scores.

RESULTS

Overall, we treated 43 hips in 28 patients with autologous stem cell implantation, with an average follow up of 16 months. Patients ranged from ARCO Ia to ARCO IIc classification of AVN. The average pre-operative visual analogue scale (VAS) of pain was 7.8. Post operatively, the average VAS score decreased to 2.5 (p < 0.0001), with 78% of patients reporting at least a 50% decrease in pain. 40 of the 43 operatively treated hips showed no radiologic progression of the disease during the follow up period, while 3 of the 43 hips had evidence of femoral head collapse and needed subsequent total hip arthroplasty at an average of 17 months after the initial decompression.

CONCLUSION

Our findings indicate that hip compression with autologous stem cell implantation for AVN of the femoral head provides significant symptomatic relief and may be beneficial in arresting progression of disease.

Increased serum protein levels by Yuanshi Shengmai Chenggu Tablet in treatment of avascular osteonecrosis of the femoral head

The traditional Chinese medicine (TCM) Yuanshi Shengmai Chenggu Tablet is used for treating the common orthopedic disease, hormone‑induced avascular necrosis of the femoral head (ANFH) in China. However, its underlying mechanism and the changes induced in the treatment of ANFH remain to be fully elucidated. In the present study, through the use of isobaric Tag for Relative and Absolute Quantitation and multiple reaction monitoring quantifications, corticosteroid‑induced femoral head necrosis and the effects of treatment with Yuanshi Shengmai Chenggu Tablet were examined. The aim was to identify serum proteins, which may be potential serum markers for the early clinical diagnosis of ANFH, and maybe used to develop more rapid and convenient detection strategies. A total of five proteins were identified, comprising Ig mu chain C region, keratin, type I cytoskeletal 9, properdin, apolipoprotein A‑IV, and IQ and AAA domain‑containing protein 1. The expression levels of all five proteins were lower in ANFH and were higher following TCM treatment. These findings were confirmed using ELISA and western blot analysis.

Case report: primary osteonecrosis associated with thrombophilia-hypofibrinolysis and worsened by testosterone therapy

Background

Familial and acquired thrombophilia are often etiologic for idiopathic hip and jaw osteonecrosis (ON), and testosterone therapy (TT) can interact with thrombophilia, worsening ON.

Case presentation

Case 1: A 62-year-old Caucasian male (previous deep venous thrombosis), on warfarin 1 year for atrial fibrillation (AF), had non-specific right hip-abdominal pain for 2 years. CT scan revealed bilateral femoral head ON without collapse. Coagulation studies revealed Factor V Leiden (FVL) heterozygosity, 4G/4G plasminogen activator inhibitor (PAI) homozygosity, high anti-cardiolipin (ACLA) IgM antibodies, and endothelial nitric oxide (NO) synthase (eNOS) T786C homozygosity (reduced conversion of L-arginine to NO, required for bone health). Apixaban 5 mg twice daily was substituted for warfarin; and L-arginine 9 g/day was started to increase NO. On Apixaban for 8 months, he became asymptomatic. Case 2: A 32-year-old hypogonadal Caucasian male had 10 years of unexplained tooth loss, progressing to primary jaw ON with cavitation 8 months after starting TT gel 50 mg/day. Coagulation studies revealed FVL heterozygosity, PAI 4G/4G homozygosity, and the lupus anticoagulant. TT was discontinued. Jaw pain was sharply reduced within 2 months.

Conclusions

Idiopathic ON, often caused by thrombophilia-hypofibrinolysis, is worsened by TT, and its progression may be slowed or stopped by discontinuation of TT and, thereafter, anticoagulation. Recognition of thrombophilia-hypofibrinolysis before joint collapse facilitates anticoagulation which may stop ON, preserving joints.

Association between alcohol-induced osteonecrosis of femoral head and risk variants of MMPS in Han population based on a case-control study

The study aimed to evaluate the association between MMP gene superfamily and alcohol-induced osteonecrosis of femoral head (alcohol-induced ONFH) risk given its high prevalence, poor therapeutic effect, and serious clinical prognosis. 308 subjects (mean age, 49.47 years; males, 64.0%) who participated in our control group and 300 alcohol-induced ONFH patients (mean age, 43.29 years; males, 99.7%) formed the case group was enrolled to estimate by statistical analysis. We selected 23 single nucleotide polymorphisms (SNPs) from MMPs, and performed the chi-squared test, Fisher's exact test, t-test and genetic model analyses. From the result, rs243849 which located in MMP2 were 1.355 (1.014-1.811), 1.34 (1.01-1.78) in allele model and log-addictive model, respectively. And the p-value of rs243849 in Cochran-Armitage trend test is 0.044. Unfortunately, the similar results of these SNPs were not observed when adjusted by gender and age. Our study is not enough to supply a positive result to benefit for alcohol-induced ONFH clinical prevention, but guide out a new direction for further experiment.

Disease activity as a major risk factor for osteonecrosis in early systemic lupus erythematosus

This study Identifies the possible risk factors for osteonecrosis (ON) in a homogenous group of early system lupus erythematosus (SLE). Forty-six consecutive SLE patients (<5 years duration) followed at the Lupus Clinic, were enrolled between 2004 and 2005. An extensive clinical and laboratory evaluation using a standard electronic protocol established since 1999, including osteonecrosis symptoms and appropriate magnetic resonance imaging (MRI), were carried out at 1—6 months intervals. All other asymptomatic for osteonecrosis patients at study entry underwent MRI. ON confirmed by MRI was found in 10 of 46 patients (22%). Age, disease duration, clinical vascular features, frequency of thrombophilia and hypofibrinolysis factors and the lipoprotein profile were comparable in patients with and without osteonecrosis ( P > 0.05). Remarkably, the frequency of patients with system lupus erythematosus disease activity index (SLEDAI) ≥8 in the previous year of osteonecrosis clinical diagnosis was significantly higher when compared to patients without this manifestation (60.0% versus 19.4%, P = 0.011), supported by the higher glucocorticoid cumulative dose in the same period ( P = 0.045). In contrast, these two parameters evaluated in 13th—24th months preceding osteonecrosis diagnosis were similar in patients with and without osteonecrosis ( P > 0.05). In the logistic regression analysis only SLEDAI remained as an independent risk factor for ON (OR = 6.78, CI = 1.05—43.55, P = 0.04). Disease activity in the previous year of ON clinical diagnosis is the main predictor factor for the development of this complication in early SLE. Lupus (2007) 16, 239—244.

The development of thromboembolism may increase the risk of osteonecrosis in children with acute lymphoblastic leukemia

Previous studies indicate pathophysiological and epidemiological parallels between osteonecrosis (ON) and thromboembolism (TE), two common treatment-related morbidities in acute lymphoblastic leukemia (ALL). To elucidate risk factors for ON and explore the relationship between ON and TE, we undertook a retrospective study of children (n = 208) with ALL. Twenty-one (10.1%) children developed ON and 42 (20.2%) TE on therapy. Thromboembolism was a significant predictor of ON on univariate (OR 8.85) and multivariate analysis, along with older age and PEGylated asparaginase. This observation supports a role for hypercoagulability in the pathogenesis of ON. Larger prospective studies are needed to further test these findings.

Genetic variation in the coagulation factor V gene and risk of femoral head osteonecrosis

Osteonecrosis of the femoral head (ONFH) is characterized by the death of the cellular portion of the femoral head due a reduction or disruption in the blood supply. Certain studies have implicated coagulation disorders, including thrombophilia and hypofibrinolysis, in the pathogenesis of ONFH. The factor V (F5) Leiden mutation has been suggested to be a genetic risk factor for venous thromboembolism and osteonecrosis in Caucasian individuals, however, this association remains controversial in other populations. The present study aimed to identify polymorphisms of the F5 gene and performed a case‑control study in a Korean population. The F5 gene was sequenced in 24 unrelated Korean individuals, and 16 polymorphisms were detected. A total of six polymorphisms were genotyped in 423 patients with ONFH and 348 control individuals. Analysis of the association between genotyped single nucleotide polymorphisms and haplotypes and with ONFH was performed. Comparison of the ONFH samples and the control individuals using logistic regression models revealed no statistically significant difference in the frequencies of the F5 polymorphisms and haplotypes. These findings suggested that F5 polymorphisms were not significant in the susceptibility to ONFH in the Korean population.

Medical treatment of osteonecrosis of the knee associated with thrombophilia-hypofibrinolysis

In 6 patients with stage II knee osteonecrosis, all 6 with thrombophilia and 4 with concurrent hypofibrinolysis, the authors prospectively determined whether anticoagulation with enoxaparin could prevent collapse and progression to osteoarthritis, ameliorate pain, and restore function. The 6 patients were treated with enoxaparin (40 to 60 mg/d for 3 or more months) as mandated by a US Food and Drug Administration-approved protocol. In post-enoxaparin prospective follow-up, patients were reassessed clinically every 4 to 6 months, and radiographs were obtained every year. The 6 patients followed up at 15.1, 7.5, 3.9, 2.25, 2, and 1 year, respectively. None progressed to joint collapse or severe osteoarthritis. Four became and remained asymptomatic at 2-, 3.9-, 7.5-, and 15.1-year follow-up, respectively. A fifth patient did not progress to collapse or severe osteoarthritis but had residual pain at 2.25-year follow-up. The sixth patient had no symptomatic benefit on enoxaparin but improved on rivaroxaban at 1-year follow-up. Two patients had recurrences of knee pain 1 and 4 years after their initial treatment with enoxaparin. One resolved after a second course of enoxaparin, and the other, with a second recurrence 1 year after the second course, resolved after a third course. Pretreatment, all 6 patients required canes, crutches, or wheelchairs, but after enoxaparin, no patient required them, and walking was unrestricted. Thrombophilia-hypofibrinolysis contributes to the pathogenesis of knee osteonecrosis. Thrombophilic-hypofibrinolytic patients with stage II knee osteonecrosis treated with enoxaparin have had no collapse or progression to severe osteoarthritis, and most have had resolution of pain and restoration of full function. This represents a major improvement compared with the natural history of untreated spontaneous knee osteonecrosis.

Single nucleotide polymorphisms other than factor V Leiden are associated with coagulopathy and osteonecrosis of the femoral head in Chinese patients

Single nucleotide polymorphisms (SNPs) of factor V Leiden have been associated with osteonecrosis of the femoral head (ONFH) in Caucasians but remains controversial in Asians. We used an SNP microarray to screen 55 loci of factor V gene in patients with ONFH of Chinese. Significantly different candidate SNPs at 14 loci were analyzed in 146 patients and 116 healthy controls using MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry and gene sequencing. The factor V Leiden (rs6025) was not found in all participants. Six SNP loci (rs9332595, rs6020, rs9332647, rs3766110, rs10919186, and rs12040141) were confirmed with significant differences in patients but not in controls. The rs6020 G-to-A polymorphism was found in 88.9% of the patients. In addition, a high percentage (87.6%) of the patients had an abnormal coagulation profile that included hyperfibrinogen, elevated fibrinogen degradation products, elevated D-dimer, abnormal protein S, abnormal protein C, or a decrease in anti-thrombin III. Patients with the rs6020 G-to-A polymorphism (mutation) had a higher risk (odds ratio: 4.62; 95% confidence interval: 1.44-14.8) of having coagulation abnormalities than did those without the mutation (wild-type) (χ(2) p  =  0.006). Our findings suggested that the rs6020 polymorphism might be the genetic trait that accounts for the higher prevalence of ONFH in the Chinese population than in Westerners. Exposure to risk factors such as alcohol and steroids in patients with the rs6020 polymorphism causes coagulation abnormalities and, subsequently, thromboembolisms in the femoral head.

Prevalence of genetic risk factors related with thrombophilia and hypofibrinolysis in patients with osteonecrosis of the femoral head in Poland

Background

The etiology of osteonecrosis of femoral head (ONFH) has not been fully elucidated. Increased intravascular coagulation and/or hypofibrinolysis have been proposed as pathogenic mechanisms. Previous reports demonstrated significant association between incidence of ONFH and polymorphisms of genes related with thrombophilia especially in Caucasian subjects. The aim of our study was to evaluate the relationship between genetic mutations leading to coagulation disorders and ONFH in Polish patients.

Methods

We have investigated the frequencies of four markers among 68 unrelated individuals with clinically and radiographically documented ONFH and among 100 healthy unrelated blood donors in Eastern part of Poland. The three genes were involved in thrombophilia: factor V Leiden (G1691A), prothrombin (G20210A), Methylenetetrahydrofolate Reductase (MTHFR C677T) and one in hypofibrinolysis: Tissue Plasminogen Activator (PLAT TPA25 I/D). The samples were genotyped with polymerase chain reaction followed by restriction enzyme analysis for the restriction fragment length polymorphisms. The allele and genotype frequencies were analyzed in the relation to ONFH etiology (idiopathic and secondary), gender, age (patients younger or older than 50 years) and the number of affected joints (unilateral or bilateral ONFH).

Results

No significant difference in allele frequencies between patients and control groups were observed in genes involved in thrombophilia. We have found a statistically significant increased frequency of D allele of PLAT TPA 25 I/D polymorphism between the entire group of patients with ONFH and controls (p=0,026, OR=1,54, CI 0,99-2,4). D allele frequency was also significantly increased in patients with primary ONFH (p=0,009, OR=1,81 CI 1,1-3,01), in males (p= 0,013; OR 1,74; 95% CIs 1,08-2,78), patients older than 50 years (p= 0,018, OR= 2,04; 95% CIs 1,09-3,82) and in cases with bilateral ONFH (p= 0,01; OR= 1,92; 95% CIs 1,13-3,27) (Table 9). The differences in DD homozygous genotype frequency were statistically significant for patients with idiopathic ONFH compared with control group (p=0,023, OR=2,75, CI 0,99-7,9) and in cases of bilateral ONFH (p=0,034; OR 3,12; 95% CIs 1,06-9,18) (Table 10). The frequencies of ID heterozygous genotype were statistically significantly higher in entire group of patients with ONFH (p=0,004 OR 2,71; 95% CIs 1,32-5,57), idiopathic ONFH (p= 0,01; OR 2,91; 95% CIs 1,24-6,87), males (p=0,0007; OR 3,75; 95% CIs 1,67-8,42), patients older than 50 years (p=0,001; OR 6,89; 95% CIs 1,87-25,84) and in cases with bilateral ONFH (p=0,009; OR 3,19; 95% CIs 1,26-8,03).

Conclusion

The results suggest that inherited hypofibrinolysis is a risk factor of idiopathic ONFH in Polish population.

Endothelial nitric oxide synthase gene polymorphisms and the risk of osteonecrosis of the femoral head in systemic lupus erythematosus

PURPOSE

Nitric oxide (NO), a short-lived gaseous free radical, is a potent mediator of biological responses involved in the pathogenesis of autoimmune rheumatic diseases, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Nitric oxide also serves as an important signal in physiological processes, including angiogenesis, thrombosis, and bone turnover, which are known to be related to the pathogenesis of osteonecrosis. We investigated whether NOS3 gene polymorphisms are associated with risk of osteonecrosis of the femoral head (ONFH).

METHODS

Five polymorphisms in the NOS3 gene were genotyped using TaqMan assays in 306 controls, 150 SLE patients, and 50 SLE patients with ONFH (SLE_ONFH).

RESULTS

We found that Asp258Asp and Glu298Asp (G894T) polymorphisms in the NOS3 gene were significantly associated with risk of ONFH. Additionally, we calculated haplotype frequencies of a linkage disequilibrium (LD) block in NOS3 (rs1799983 - rs1800780) and tested for haplotype associations. The haplotypes G-A and T-A showed significant protective (P = 1.6 × 10(-3); OR 0.39, 95 % confidence intervals (CI) 0.22-0.7) and increased risk (P = 2.0 x 10(-5)-6.0 x 10(-4); OR 3.17-3.73) effects for ONFH, respectively.

CONCLUSIONS

These results suggest that exonic NOS3 polymorphisms may increase the risk of ONFH in Korean SLE patients.

Meta-analysis of Factor V Leiden G1691A polymorphism and osteonecrosis of femoral head susceptibility

Testing for genetic risk associations between Factor V Leiden (FVL) and the osteonecrosis of femoral head (ONFH) is common, however, inconsistent results have been previously obtained. To summarize results on the association of FVL mutation polymorphism with ONFH in various populations and to calculate the overall genetic risk factors, we performed a search of electronic databases including PubMed, Elsevier Science Direct, Chinese National Knowledge Infrastructure and the Chinese Biomedical Database to identify published studies correlating the FVL mutation with ONFH. Statistical analysis was performed using Review Manager (RevMan) version 5.0 and Stata statistical software (version 10). We identified 57 titles and included 7 studies comprising 481 cases and 867 controls in this meta-analysis. The groups were pooled, and a significant association between FVL mutation and increased ONFH was found (OR=4.55, 95% CI, 2.75-7.52, P<0.00001). This meta-analysis demonstrated that FVL plays an important role in non-Asian populations. Large sample studies including different ethnic groups and age- and gender-matched groups, as well as multiple gene polymorphism detection should be considered to clarify the association of FVL mutation polymorphism and ONFH susceptibility in the future.

Coagulation disorders in patients with femoral head osteonecrosis

OBJECTIVE:

To compare the occurrence of thrombophilic disorders in patients with idiopathic osteonecrosis of the femoral head and patients with secondary osteonecrosis of the femoral head.

METHODS:

Twenty-four consecutive patients were enrolled, with eight of them presenting idiopathic osteonecrosis and 16 presenting secondary osteonecrosis. The tests for detection of thrombophilic disorders were measurements of protein C, protein S and antithrombin levels and detection of prothrombin and factor V gene mutations. We compared the results using the odds ratio statistics for the thrombophilic disorders between the two groups.

RESULTS:

The odds ratio for the protein S deficiency and protein C deficiency between the idiopathic and secondary groups were 5 and 2.14, respectively. Thus, an individual with idiopathic osteonecrosis has 5 times more chance of presenting protein S deficiency and 2.14 times more chance of presenting protein C deficiency than an individual with secondary osteonecrosis.

CONCLUSION:

Patients with idiopathic osteonecrosis have more chances of presenting thrombophilias than those with secondary osteonecrosis, suggesting these coagulation disorders can play an important role in the pathogenesis of the osteonecrosis in cases where there was no initial risk factor recognized. Level of Evidence III, Case-Control Study.

Inherited thrombophilia may be a causative factor for osteonecrosis of femoral head in male patients with developmental dysplasia of the hip: a case series

PURPOSE

The aim of this case series was to assess the effect of two common causes of inherited thrombophilia, factor V Leiden (FVL) and prothrombin mutation (PTM) on the development of osteonecrosis of the femoral head (ONFH) following the treatment of developmental dysplasia of the hip (DDH).

METHODS

FVL and PTM analysis of 58 patients (45 females and 13 males; mean age 12.2 years) with ONFH due to DDH treatment was done.

RESULTS

Rate of inherited thrombophilia (FVL plus PTM) was 15.5 %. Inherited thrombophilia was nearly four times higher in male patients than in female patients and this difference was mainly due to FVL (P < 0.05). This finding was against the common belief that, coagulation abnormalities were equally distributed across the sexes in normal population. Rates of overall inherited thrombophilia, FVL and PTM were not correlated with the type of ONFH (P > 0.05).

CONCLUSION

Hereditary thrombophilia, especially FVL, may be one of the causative factors for the development of ONFH following DDH treatment in male patients. Further prospective, controlled studies are needed to undoubtedly enlighten this issue.

The role of the factor V Leiden mutation in osteonecrosis of the hip

We examined the hypothesis that the factor V Leiden (FVL) and G20101A prothrombin gene mutations are commonly associated with hip osteonecrosis. We prospectively evaluated 244 consecutively referred adults with osteonecrosis (ON), 161 idiopathic and 83 secondary. Cases (n = 244) did not differ from 104 normal controls by race. Of the 244 patients, 23 (9.4%) were FVL heterozygotes versus 2 of 104 controls (1.9%), P = .013, risk ratio (RR) = 4.90, 95% confidence interval (CI) 1.18 to 20.4. Of the 161 patients with idiopathic ON, 15 (9.3%) were FVL heterozygotes versus 2 of 104 normal controls (1.9%), P = .017, RR = 4.84, 95% CI 1.13 to 20.8. Of the 83 patients with secondary ON, 8 (9.6%) FVL heterozygotes versus 2 of 104 normal controls (1.9%), P = .024, RR = 5.01, 95% CI 1.09 to 23.0. Prothrombin gene heterozygosity in normal controls (2.9%) did not differ from ON cases (3.4%), P = 1.0. The thrombophilic FVL mutation is commonly associated with and may be pathoetiologic for hip osteonecrosis.

Clinical analysis of osteonecrosis of the femoral head induced by steroids

OBJECTIVE

To explore the clinical characteristics of osteonecrosis of the femoral head (ONFH) induced by steroids.

METHODS

From January 2000 to October 2009, 497 hips in 270 cases of ONFH induced by steroids were studied. A questionnaire was administered when the patients were admitted; the questions concerned the underlying disease, duration of steroid usage, total dosage of steroid, incubation period (time interval between commencement of steroid therapy and onset of pain), severity of pain, location of initial complaint, primary diagnosis, time lag from onset of pain to final diagnosis and physical signs when admitted. The correlations between pain and Association Research Circulation Osseous (ARCO) stage, bone marrow edema (BME) and lesion size were analyzed.

RESULTS

The median of time between commencing steroid medication and developing ONFH for the 269 cases was 18 months (range, 2-384 months). 78.82% cases presented with pain within three years of steroid initiation, only 10.41% patients first complained of pain six or more years after commencing steroid therapy. Fifty-six cases (20.82%) were misdiagnosed, lumbar disorders being the most frequent misdiagnoses. 79.29% of symptomatic hips presented with abnormal physical tests. Of 420 symptomatic hips, 166 hips were type C1, 223 hips type C2; 299 hips had collapsed; and there was BME in 209 hips.

CONCLUSION

Most patients with ONFH induced by steroids complained of pain within 3 years of commencing steroid therapy. Pain was associated with lesion size, collapse and BME. Atypical location of pain, failure to perform a physical examination and MRI findings were the main causes of misdiagnoses.

Thrombotic events after starting exogenous testosterone in men with previously undiagnosed familial thrombophilia

Our specific aim was to describe thrombosis (osteonecrosis of the hips, pulmonary embolism, and amaurosis fugax) after exogenous testosterone was given to men with no antecedent thrombosis and previously undiagnosed familial thrombophilia. After starting testosterone patch or gel, 50 mg/day or intramuscular testosterone 400 mg IM/month, 2 men developed bilateral hip osteonecrosis 5 and 6 months later, and 3 developed pulmonary embolism 3, 7, and 17 months later. One man developed amaurosis fugax 18 months after starting testosterone gel 50 mg/day. Of these 6 men, 5 were found to have previously undiagnosed factor V Leiden heterozygosity, 1 of whom had ancillary MTHFR C677T homozygosity, and 2 with ancillary MTHFR C677T-A1298C compound heterozygosity. One man had high factor VIII (195%), factor XI (179%), and homocysteine (29.3 umol/L). Thrombotic events after starting testosterone therapy are associated with familial thrombophilia. We speculate that when exogenous testosterone is aromatized to E2, and E2-induced thrombophilia is superimposed on familial thrombophilia, thrombosis occurs. Men sustaining thrombotic events on testosterone therapy should be screened for the factor V Leiden mutation and other familial and acquired thrombophilias.

Significant associations of PAI-1 genetic polymorphisms with osteonecrosis of the femoral head

BACKGROUND

The pathogenesis of osteonecrosis of the femoral head (ONFH) has been implicated in hypofibrinolysis and blood supply interruption. Previous studies have demonstrated that decreased fibrinolytic activity due to elevated plasminogen activator inhibitor-1 (PAI-1) levels correlates with ONFH pathogenesis. The -675 4G/5G single nucleotide polymorphism (SNP rs1799889) in the PAI-1 gene promoter is associated with PAI-1 plasma level. We investigated whether rs1799889 and two other SNPs of the PAI-1 gene (rs2227631, -844 G/A in the promoter; rs11178, +10700 C/T in the 3'UTR) are associated with increased ONFH risk.

METHODS

Three SNPs in PAI-1 were genotyped in 206 ONFH patients and 251 control subjects, using direct sequencing and a TaqMan® 5' allelic discrimination assay. We performed association analysis for genotyped SNPs and haplotypes with ONFH.

RESULTS

The 4G allele of rs1799889, A allele of rs2227631, and C allele of rs11178 were significantly associated with increased ONFH risk (p = 0.03, p = 0.003, and p = 0.002, respectively). When we divided the population according to gender, an association between the three SNPs and increased risk of ONFH was found only in men. In another subgroup analysis based on the etiology of ONFH, rs2227631 (A allele) and rs11178 (C allele) in the idiopathic subgroup (p = 0.007 and p = 0.021) and rs1799889 (4G allele) and rs11178 (C allele) in the alcohol-induced subgroup (p = 0.042 and p = 0.015) were associated with increased risk of ONFH. In addition, a certain haplotype (A-4G-C) of PAI-1 was also significantly associated with ONFH (p < 0.001).

CONCLUSION

Our findings demonstrated that three SNPs (rs1799889, rs2227631, and rs11178) of the PAI-1 gene were associated with ONFH risk. This study also suggests that PAI-1 SNPs may play an important role in ONFH.

Idiopathic and secondary osteonecrosis of the femoral head show different thrombophilic changes and normal or higher levels of platelet growth factors

BACKGROUND AND PURPOSE

Thrombophilia represents a risk factor both for idiopathic and secondary osteonecrosis (ON). We evaluated whether clotting changes in idiopathic ON were different from corticosteroid-associated ON. As platelet-rich plasma has been proposed as an adjuvant in surgery, we also assessed whether platelet and serum growth factors were similar to those in healthy subjects.

METHODS

18 patients with idiopathic ON and 18 with corticosteroid-associated ON were compared with 44 controls for acquired and inherited thrombophilia. Platelet factor 4 (PF4), transforming growth factor-β1, platelet-derived growth factor-BB (PDGF-BB), and vascular endothelial growth factor were assayed in the supernatants of thrombin-activated platelets, in platelet lysates, and in serum from 14 ON patients and 10 controls.

RESULTS

Idiopathic ON patients had higher plasminogen levels (median 118%) than controls (101%) (p = 0.02). Those with corticosteroid-associated ON had significantly higher D-dimer (333 ng/mL) and lower protein C levels (129%) than controls (164 ng/mL, p = 0.004; 160%, p = 0.02). The frequency of inherited thrombophilia was not different from the controls. No statistically significant differences were found between idiopathic and corticosteroid-associated ON. 20 of the 36 ON patients were smokers. (The controls were selected from smokers because nicotine favors hypercoagulability). ON patients had significantly higher serum PF4 levels (7,383 IU/mL) and PDGF-BB levels (3.1 ng/mL) than controls (4,697 IU/mL, p = 0.005; 2.2 ng/mL, p = 0.02).

INTERPRETATION

Acquired hypercoagulability was common in both ON types, but the specific changes varied. The release of GF from platelets was not affected, providing a biological basis for platelet-rich plasma being used as an adjuvant in surgical treatment.

Genetic association of angiogenesis- and hypoxia-related gene polymorphisms with osteonecrosis of the femoral head

Multiple factors have been implicated in the development of osteonecrosis of the femoral head (ONFH). In particular, non-traumatic ONFH is directly or indirectly related to injury of the vascular supply to the femoral head. Thus, hypoxia in the femoral head caused by impaired blood flow may be an important risk factor for ONFH. In this study, we investigated whether genetic variations of angiogenesis- and hypoxia-related genes contribute to an increased risk for the development of ONFH. Candidate genes were selected based on known hypoxia and angiogenesis pathways. An association study was performed using an Affymetrix Targeted Genotyping 3K Chip array with 460 ONFH patients and 300 control subjects. We showed that single nucleotide polymorphisms (SNPs) in the genes TF, VEGFC, IGFBP3, and ACE were associated with an increased risk of ONFH. On the other hand, SNPs in the KDR and NRP1 genes were associated with protection against ONFH. The most important finding was that one SNP (rs2453839) in the IGFBP3 gene was significantly associated with a higher risk of ONFH (P=0.0061, OR 7.74). In subgroup analysis, most candidate gene variations that were associated with ONFH occurred in the idiopathic subgroup. Among other SNPs, ACE SNPs were associated with steroid-induced ONFH (P=0.0018-0.0037, OR>3). Collectively, our findings suggest that genetic variations in angiogenesis- and hypoxia-related genes may help to identify susceptibility factors for the development of ONFH in the Korean population.

Lack of association of MTHFR gene polymorphisms with the risk of osteonecrosis of the femoral head in a Korean population

Some studies have suggested that coagulation disorders may be implicated in osteonecrosis of the femoral head (ONFH). The C677T polymorphism of the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene has been postulated to be a genetic risk factor for venous thromboembolism and osteonecrosis in Caucasians, but this relationship has not been established in other populations. In this study, we conducted case-control analysis of whether MTHFR polymorphisms are associated with ONFH in Korean patients. Fifteen single nucleotide polymorphisms (SNPs) were selected and genotyped in 443 ONFH patients and 273 control subjects using the TaqMan 5' allelic discrimination assay. Comparison of ONFH and control subjects using logistic regression models revealed no statistically significant differences in the frequencies of the MTHFR polymorphisms and haplotypes. Further analysis stratified by etiology also showed no association. These results suggest that MTHFR polymorphisms play no significant role in susceptibility to ONFH in the Korean population.

T-786C polymorphism of the endothelial nitric oxide synthase gene and neuralgia-inducing cavitational osteonecrosis of the jaws

OBJECTIVE

We hypothesized that, similar to idiopathic hip osteonecrosis, the T-786C mutation of the endothelial nitric oxide synthase (eNOS) gene affecting nitric oxide (NO) production was associated with neuralgia-inducing cavitational osteonecrosis of the jaws (NICO).

DESIGN

In 22 NICO patients, not having taken bisphosphonates, mutations affecting NO production (eNOS T-786C, stromelysin 5A6A) were measured by polymerase chain reaction. Two healthy normal control subjects were matched per case by race and gender.

RESULTS

Homozygosity for the mutant eNOS allele (TT) was present in 6 out of 22 patients (27%) with NICO compared with 0 out of 44 (0%) race and gender-matched control subjects; heterozygosity (TC) was present in 8 patients (36%) versus 15 control subjects (34%); and the wild-type normal genotype (CC) was present in 9 patients (36%) versus 29 controls (66%) (P = .0008). The mutant eNOS T-786C allele was more common in cases (20 out of 44 [45%]) than in control subjects (15 out of 88 [17%]) (P = .0005). The distribution of the stromelysin 5A6A genotype in cases did not differ from control subjects (P = .13).

CONCLUSIONS

The eNOS T-786C polymorphism affecting NO production is associated with NICO, may contribute to the pathogenesis of NICO, and may open therapeutic medical approaches to treatment of NICO through provision of L-arginine, the amino-acid precursor of NO.

Osteonecrosis of the metacarpal head in a patient with a prothrombin 20210A gene mutation

Osteonecrosis of the metacarpal head is rare and of unknown cause. We describe a 17-year-old girl with osteonecrosis of the fourth metacarpal head and a mutated prothrombin 20210A gene, which suggests a possible relation between a hypercoagulable state and osteonecrosis of the metacarpal head.