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

Excess glucocorticoids inhibit murine bone turnover via modulating the immunometabolism of the skeletal microenvironment

Elevated bone resorption and diminished bone formation have been recognized as the primary features of glucocorticoid-associated skeletal disorders. However, the direct effects of excess glucocorticoids on bone turnover remain unclear. Here, we explored the outcomes of exogenous glucocorticoid treatment on bone loss and delayed fracture healing in mice and found that reduced bone turnover was a dominant feature, resulting in a net loss of bone mass. The primary effect of glucocorticoids on osteogenic differentiation was not inhibitory; instead, they cooperated with macrophages to facilitate osteogenesis. Impaired local nutrient status - notably, obstructed fatty acid transportation - was a key factor contributing to glucocorticoid-induced impairment of bone turnover in vivo. Furthermore, fatty acid oxidation in macrophages fueled the ability of glucocorticoid-liganded receptors to enter the nucleus and then promoted the expression of BMP2, a key cytokine that facilitates osteogenesis. Metabolic reprogramming by localized fatty acid delivery partly rescued glucocorticoid-induced pathology by restoring a healthier immune-metabolic milieu. These data provide insights into the multifactorial metabolic mechanisms by which glucocorticoids generate skeletal disorders, thus suggesting possible therapeutic avenues.

Harnessing Biomaterials for Safeguarding Chimeric Antigen Receptor T Cell Therapy: An Artful Expedition in Mitigating Adverse Effects

Chimeric antigen receptor T cell (CAR-T) therapy has emerged as a groundbreaking approach in cancer treatment, showcasing remarkable efficacy. However, the formidable challenge lies in taming the formidable side effects associated with this innovative therapy, among which cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS) and on-target off-tumor toxicities (OTOT) are typical representatives. Championing the next frontier in cellular immunotherapy, this comprehensive review embarks on an artistic exploration of leveraging biomaterials to meticulously navigate the intricate landscape of CAR-T cell therapy. Unraveling the tapestry of potential toxicities, our discourse unveils a symphony of innovative strategies designed to elevate the safety profile of this revolutionary therapeutic approach. Through the lens of advanced medical science, we illuminate the promise of biomaterial interventions in sculpting a safer and more efficacious path for CAR-T cell therapy, transcending the boundaries of conventional treatment paradigms.

Knee Osteonecrosis After SARS-CoV-2 Virus Infection

ABSTRACT

Osteonecrosis after COVID-19 infection is a complex pathology with multifactorial origin. Factors such as infection itself with associated coagulopathy, as well as genetic mechanisms, and medications used for its treatment such as corticosteroids, may also be involved. The variability in the presentation makes diagnosis difficult, which, if done soon, can help delay progression and reduce morbidity and the need for surgery.This report presents a case of knee osteonecrosis in a female patient who did not have previous knee pathology on imaging tests. She was diagnosed by magnetic resonance imaging months after hospital admission for SARS-CoV-2 pneumonia, which required high-dose corticosteroid treatment.

Who is the convict; COVID-19 or corticosteroid? Late onset avascular necrosis of hips after COVID-19. A case report with literature review

AIM

Avascular necrosis (AVN) or osteonecrosis is characterized by death of bone tissue due to endothelial damage and vascular abnormality. Coronavirus can induce endothelial damage and abnormal blood clotting, so that COVID-19 is known as a vascular disease. We aim to evaluate the relationship between AVN and COVID-19.

CASE

Here we present a 39-year old man with severe COVID-19 and corticosteroid consumption who developed late onset AVN of both hips 20 month after COVID-19.

CONCLUSION

An awareness of the possible osteonecrosis for all physicians dealing with patients with musculoskeletal problems following COVID-19 is necessary.

Femoral head avascular necrosis in COVID-19 survivors: a systematic review

The current systematic review aimed to document published cases of femoral head avascular necrosis (FHAVN) post-COVID-19, to report the COVID-19 disease characteristics and management patients received, and to evaluate how the FHAVN were diagnosed and treated among various reports. A systematic literature review was performed per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines through a comprehensive English literature search on January 2023 through four databases (Embase, PubMed, Cochrane Library, and Scopus), including studies reporting on FHAVN post-COVID-19. Fourteen articles were included, ten (71.4%) were case reports, and four (28.6%) case series reported on 104 patients having a mean age of 42.2 ± 11.7 (14:74) years, in which 182 hip joints were affected. In 13 reports, corticosteroids were used during the COVID-19 management plan for a mean of 24.8 ± 11 (7:42) days, with a mean prednisolone equivalent dose of 1238.5 ± 492.8 (100:3520) mg. A mean of 142.1 ± 107.6 (7:459) days passed between COVID-19 diagnosis and FHAVN detection, and most of the hips were stage II (70.1%), and concomitant septic arthritis was present in eight (4.4%) hips. Most hips (147, 80.8%) were treated non-surgically, of which 143 (78.6%) hips received medical treatment, while 35 (19.2%) hips were surgically managed, 16 (8.8%) core decompression, 13 (7.1%) primary THA, five (2.7%) staged THA and three (1.6%) had first stage THA (debridement and application of antibiotic-loaded cement spacer). The outcomes were acceptable as regards hip function and pain relief. Femoral head avascular necrosis post-COVID-19 infection is a real concern, primarily attributed to corticosteroid usage, besides other factors. Early suspicion and detection are mandatory, as conservative management lines are effective during early stages with acceptable outcomes. However, surgical intervention was required for progressive collapse or patients presented in the late stage.

Phase-contrast imaging with synchrotron hard X-ray reveals the effect of icariin on bone tissue morphology and microstructure in rabbits with early glucocorticoid-induced osteonecrosis of the femoral head

Background: Phase-contrast imaging (PCI) with synchrotron hard X-ray was used to observe the changes in bone tissue morphology and microstructure in rabbit models of early glucocorticoid-induced osteonecrosis of the femoral head (ONFH), and to evaluate the intervention effect of Icariin. Methods: Fifty mature New Zealand rabbits (weighing 2.5-3.0 kg) were randomly divided into a control group (n = 10), a glucocorticoid group (n = 20), and an Icariin group (n = 20). The glucocorticoid group and the Icariin group were sequentially injected with lipopolysaccharide (LPS) and methylprednisolone (MPS) to establish a glucocorticoid-induced ONFH animal model. The Icariin group was given Icariin solution when methylprednisolone was injected for the first time, and the control group and glucocorticoid group were given the same amount of normal saline. Animals were sacrificed after 6 weeks, and bilateral femoral head specimens were taken for research. The right femoral head was observed by PCI with synchrotron hard X-ray technology, and the left femoral head was verified by Micro-CT scanning and HE staining. Results: Forty-three animals (nine in the control group, sixteen in the glucocorticoid group, and eighteen in the Icariin group) were included in the study. PCI with synchrotron hard X-ray revealed that the trabecular bone in the glucocorticoid group was thinned, broken, and structurally damaged, whereas the trabecular bone in the Icariin group had normal volume, thickness, and a relatively intact structure. Micro-CT scan reconstruction and HE staining were used to verify the reliability of this technique in identifying osteonecrosis. Conclusion: The effects of Icariin were observed in an early glucocorticoid-induced ONFH rabbit model using PCI with synchrotron hard X-ray. Icariin weakens the destructive effect of glucocorticoids on bone tissue structure, improves bone tissue morphology, and stabilizes bone microstructure. This technique may provide a definitive, non-invasive alternative to histological examination for the diagnosis of early ONFH.

PDGF-BB prevents destructive repair and promotes reparative osteogenesis of steroid-associated osteonecrosis of the femoral head in rabbits

Destructive repair characterized by inadequate angiogenesis and osteogenesis is the main pathological progression in steroid-associated osteonecrosis of the femoral head (SONFH). Platelet-derived growth factor-BB (PDGF-BB) is an "angiogenesis and osteogenesis coupling" factor that has been used for the treatment of bone defects in clinic. This study was designed to analyze the ability of PDGF-BB for preventing destructive repair and promoting reparative osteogenesis in SONFH. Steroid-associated osteonecrosis (SAON) was induced and triggered destructive repair of the femoral head by repeated lipopolysaccharide (LPS) and methylprednisolone (MPS) injections in rabbits. At 2, 4, and 6 weeks after induction, recombinant human PDGF-BB, neutralizing PDGF-BB antibody, or saline was intramedullary injected into the proximal femora. At week 6 after SAON induction, the proximal femora were dissected for bone architecture and histological analysis. C3H10T1/2 cells and HUVECs were used for further mechanistic investigation. After PDGF-BB treatment, type H vessels and leptin receptor-positive (LepR+) mesenchymal stem cells (MSCs) increased in the affected femoral head, and more osteoblastic osteogenesis along the bone surfaces but scattered adipocytes in bone marrow tissue than that in the SAON group. PDGF-BB treatment prevented destructive repair progression and led to 50-70 % of osteonecrotic femoral heads undergoing reparative osteogenesis. In particular, we found that PDGF-BB could mediate MSC self-renewal and maintain their osteogenic potency by activating PDGFR/Akt/GSK3β/CERB signaling in the presence of steroids. Moreover, PDGF-BB also stabled the newly formed vascular tubes by recruiting MSCs for improving intraosseous vascular integration. PDGF-BB may be a candidate for the promotion of reparative osteogenesis in SONFH.

Avascular necrosis of the epiphyses of bones in patients who have had SARS-CoV-2 infection: Clinical observations and a narrative review of literature data

The SARS-CoV-2 coronavirus pandemic is a leading medical problem that is in the focus of attention of representatives of all medical specialties. In addition to fighting the COVID-19 infection itself, the task of preventing and treating a wide range of complications arising after the disease is becoming increasingly urgent. One of these complications is avascular necrosis (AN) of bone tissue – a severe pathology that leads to serious suffering, a decrease in the quality of life and disability of patients. For the period from 2020 to 2022 there are 9 reviews in the world literature devoted to the pathogenesis, clinical features and treatment possibilities of this complication. During the same period, 5 articles were published describing clinical observations of AN after suffering COVID-19.The purpose of this work is to demonstrate our own clinical observations, as well as to review the available literature data on the problem of AN after COVID-19 infection. Based on the analysis, it can be concluded that AN after SARS-CoV-2 infection most often develops in the femoral head (>50% of cases), occurs regardless of the severity of the disease and the cumulative dose of glucocorticoids used in the acute period of the disease. It seems advisable to perform an MRI of the hip joints at least once every 3 months for all patients who have had COVID-19 in severe and moderate form during the first year after convalescence.

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.

Long-term implications of COVID-19 on bone health: pathophysiology and therapeutics

BACKGROUND

SARS-CoV-2 is a highly infectious respiratory virus associated with coronavirus disease (COVID-19). Discoveries in the field revealed that inflammatory conditions exert a negative impact on bone metabolism; however, only limited studies reported the consequences of SARS-CoV-2 infection on skeletal homeostasis. Inflammatory immune cells (T helper-Th17 cells and macrophages) and their signature cytokines such as interleukin (IL)-6, IL-17, and tumor necrosis factor-alpha (TNF-α) are the major contributors to the cytokine storm observed in COVID-19 disease. Our group along with others has proven that an enhanced population of both inflammatory innate (Dendritic cells-DCs, macrophages, etc.) and adaptive (Th1, Th17, etc.) immune cells, along with their signature cytokines (IL-17, TNF-α, IFN-γ, IL-6, etc.), are associated with various inflammatory bone loss conditions. Moreover, several pieces of evidence suggest that SARS-CoV-2 infects various organs of the body via angiotensin-converting enzyme 2 (ACE2) receptors including bone cells (osteoblasts-OBs and osteoclasts-OCs). This evidence thus clearly highlights both the direct and indirect impact of SARS-CoV-2 on the physiological bone remodeling process. Moreover, data from the previous SARS-CoV outbreak in 2002-2004 revealed the long-term negative impact (decreased bone mineral density-BMDs) of these infections on bone health.

METHODOLOGY

We used the keywords "immunopathogenesis of SARS-CoV-2," "SARS-CoV-2 and bone cells," "factors influencing bone health and COVID-19," "GUT microbiota," and "COVID-19 and Bone health" to integrate the topics for making this review article by searching the following electronic databases: PubMed, Google Scholar, and Scopus.

CONCLUSION

Current evidence and reports indicate the direct relation between SARS-CoV-2 infection and bone health and thus warrant future research in this field. It would be imperative to assess the post-COVID-19 fracture risk of SARS-CoV-2-infected individuals by simultaneously monitoring them for bone metabolism/biochemical markers. Importantly, several emerging research suggest that dysbiosis of the gut microbiota-GM (established role in inflammatory bone loss conditions) is further involved in the severity of COVID-19 disease. In the present review, we thus also highlight the importance of dietary interventions including probiotics (modulating dysbiotic GM) as an adjunct therapeutic alternative in the treatment and management of long-term consequences of COVID-19 on bone health.

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.