Pathophysiology Of Osteonecrosis Research Articles

CD4+ T Cell Profile and Activation Response in Sickle Cell Disease Patients with Osteonecrosis.

Recent evidence suggests that abnormalities involving CD4+T lymphocytes are associated with the pathophysiology of osteonecrosis (ON); however, few studies have addressed the CD4+T cells in ON related to sickle cell disease (SCD/ON). In addition, T cells producing multiple cytokines simultaneously are often present in the inflammatory milieu and may be implicated in the immune response observed in SCD/ON. In the present study, we aimed to characterize the functional status of CD4+T cells in SCD by simultaneously determining the frequency of IFN-γ+, IL-4+, and IL-17+ CD4+T in cell cultures under exogenous stimuli. Peripheral blood mononuclear cells (PB-MNCs) from 9 steady-state SCD patients, 15 SCD/ON patients, and 19 healthy controls had functional status of CD4+T cells analyzed. Bone marrow mononuclear cells (BM-MNCs) from 24 SCD/ON patients (SCD BM) and 18 patients with ON not related to SCD (non-SCD BM) were also analyzed. We found that PB-MNC of SCD patients with or without ON presented significantly reduced TCD4+, TCD8+, and TCD4+ naïve cell frequencies and increased frequency of circulating CD4+T cells able to simultaneously produce IFN-γ+/IL4+ and IL-17+/IL4+ compared to healthy controls. Conversely, the polyclonal stimulation of BM-MNC induced an increased frequency of CD4+IFN-γ+ and CD4+IL-17+ in SCD BM compared to non-SCD BM. The increased proportion of CD4+ T cells able to produce a broad spectrum of proinflammatory cytokines after a strong stimulus indicates that the immune system in SCD/ON patients presents an expressive pool of partially differentiated cells ready to take on effector function. It is possible that this increased subpopulation may extend to inflammatory sites of target organs and may contribute to the maintenance of inflammation and the pathophysiology of osteonecrosis in sickle cell disease.

Review of Current Concepts Femoral of Head Osteonecrosis

Background: The avascular necrosis (AVN) or osteonecrosis of the femur head (ONFH), an illness with several etiological factors, impacts young populace and otherwise handled prompt, causes the collapse of femur head eventually requiring hip arthroplasty. Objective: the present article aims to provide an overview of epidemiology, pathophysiology of osteonecrosis along with diagnosis methods and non-surgical in early stages and surgical treatment methods. Methodology: Comprehensive search of the literature was conducted in the following databases; PubMed, and SciVerse Scopus for studies published before November 2017. The PubMed database was searched using an algorithm comprising relevant MeSH terms including “Osteoporosis”, “femoral head osteonecrosis” AND “management” “diagnosis”. Conclusion: Osteonecrosis is a destructive pathology that eventually results in bone death through loss of blood to the bone, it involves almost every bone including the femoral head while early start of osteoarthritis could ultimately demand hip arthroplasty when non-operative procedures and joint-sparing treatments fail. Nevertheless, recent technological advances in surgical treatment methods have improved outcomes and should help patients recover from this functionally debilitating joint disease.

Genetic risk factors for the development of osteonecrosis in children under age 10 treated for acute lymphoblastic leukemia

AbstractOsteonecrosis is a dose-limiting toxicity in the treatment of pediatric acute lymphoblastic leukemia (ALL). Prior studies on the genetics of osteonecrosis have focused on patients ≥10 years of age, leaving the genetic risk factors for the larger group of children <10 years incompletely understood. Here, we perform the first evaluation of genetic risk factors for osteonecrosis in children <10 years. The discovery cohort comprised 82 cases of osteonecrosis and 287 controls treated on Children's Oncology Group (COG) standard-risk ALL protocol AALL0331 (NCT00103285, https://clinicaltrials.gov/ct2/show/NCT00103285), with results tested for replication in 817 children <10 years treated on COG protocol AALL0232 (NCT00075725, https://clinicaltrials.gov/ct2/show/NCT00075725). The top replicated single nucleotide polymorphisms (SNPs) were near bone morphogenic protein 7 [BMP7: rs75161997, P = 5.34 × 10−8 (odds ratio [OR] 15.0) and P = .0498 (OR 8.44) in the discovery and replication cohorts, respectively] and PROX1-antisense RNA1 (PROX1-AS1: rs1891059, P = 2.28 × 10−7 [OR 6.48] and P = .0077 [OR 3.78] for the discovery and replication cohorts, respectively). The top replicated nonsynonymous SNP, rs34144324, was in a glutamate receptor gene (GRID2, P = 8.65 × 10−6 [OR 3.46] and P = .0136 [OR 10.8] in the discovery and replication cohorts, respectively). In a meta-analysis, the BMP7 and PROX1-AS1 variants (rs75161997 and rs1891059, respectively) met the significance threshold of <5 × 10−8. Top replicated SNPs were enriched in enhancers active in mesenchymal stem cells, and analysis of annotated genes demonstrated enrichment in glutamate receptor and adipogenesis pathways. These data may provide new insights into the pathophysiology of osteonecrosis.

Mechanisms of bone metastasis, pathophysiology of osteonecrosis of the jaw, and integrins, platelets and bone metastasis: meeting report from skeletal complications of malignancy V

Mechanisms of bone metastasis, pathophysiology of osteonecrosis of the jaw, and integrins, platelets and bone metastasis: meeting report from skeletal complications of malignancy V

Surgical and Molecular Advances in Osteonecrosis: Editorial Comment

Surgical and Molecular Advances in Osteonecrosis: Editorial Comment

Biologic Factors Influencing Osteonecrosis: Steroids, Statins, Ethanol, Human Immunodeficiency Virus and Antiretroviral Therapy, and Smoking

Although the exact pathophysiology of osteonecrosis remains unknown, it has been associated with a wide range of conditions. Early detection and intervention are keys to salvaging the joint. Therefore awareness of well-established risk factors and associated disorders can assist in early detection and possible prevention of hip joint destruction. This review paper describes the current knowledge of the condition and analyzes the associated risk factors including steroids, statins, ethanol, HIV and antiretroviral therapy and smoking as well as discusses the strategies to minimize the morbidity.

4428 Osteonecrosis and related conditions

Objectifs pedagogiques Define the fundamental pathophysiology of osteonecrosis. Recognize the radiographie manifestations and spatial geometry of osteonecrosis and bone infarction. Identify the optimum use of the various imaging modalities available. Recognize the common associated complications. Identify differentiating features to allow a successful radiological diagnosis.

The Pathogenesis of Osteonecrosis and the Relationships to Corticosteroids

One of the challenging issues faced by allergists is a risk-benefit analysis on the use of corticosteroids. An uncommon, but serious complication of corticosteroids is the development of avascular necrosis (osteonecrosis). In this review we present the differential diagnosis and pathophysiology of osteonecrosis, with particular emphasis on steroids. Osteonecrosis of the femoral head is a common disorder that may be either naturally occurring or iatrogenic. With the exception of those cases labeled as idiopathic, the majority are the result of some insult to the vascular integrity of the affected hip. The reason for this disruption is manifold and can range from direct trauma to the more subtle or indirect compromise associated with fatty emboli or often an intravascular event such as that seen in sickle cell anemia. Although they are not totally understood, corticosteroids present a special problem because of susceptibility factors that may make some patients more likely to get osteonecrosis than others. The problem may be more complex, in that the association between corticosteroid use and osteonecrosis may be disease-dependent. In any case, any patient receiving long-term corticosteroids should be warned of this potentially debilitating complication.