Osteoporotic fractures tend to be more challenging than fractures in healthy bone and the efficacy of metal screw fixation decreases with decreasing bone mineral density making it more difficult for such screws to gain purchase. This leads to increased complication rates such as malunion, non-union and implant failure (1). Bioresorbable polymer devices have seen clinical success in fracture fixation and are a promising alternative for metallic devices but are rarely used in the osteoporotic population. To address this, we are developing a system that may allow osteoporotic patients to avail of bioresorbable devices (2) but it is important to establish if patients have any reservations about having a plastic resorbable device instead of a metal one. Therefore the aim of this study was to explore the acceptability of bioresorbable fracture fixation devices to people with osteoporosis. A cross sectional descriptive study was conducted in a UK wide population using convenience sampling. An online survey comprising nine survey questions and nine demographic questions was developed in Microsoft Teams and tested for face validity in a small pilot study (n=6). Following amendments and ethical approval, the survey was distributed by the Royal Osteoporosis Society on their website and social media platforms. People were invited to take part if they lived in the UK, were over 18 years old and had been diagnosed with osteoporosis. The survey was open for three weeks in May 2023. Responses were analysed using descriptive statistics.Abstract
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Intervertebral disc degeneration (IDD), the main cause of low back pain, is closely related to the inflammatory microenvironment in the nucleus pulposus (NP). Tumor necrosis factor-α (TNF-α) plays an important role in inflammation-related metabolic disturbance of NP cells. Melatonin has been proven to regulate the metabolism of NP cells, but whether it can protect NP cells from TNF-α-induced damage is still unclear. Therefore, this study aims to investigate the role and specific mechanism of melatonin on regulating the metabolism of NP cells in the inflammatory microenvironment. Human primary NP cells were treated with or without vehicle, TNF-α and melatonin. And the metabolic markers were also detected by western blotting and RT-qPCR. The activity of NF-κB signaling and Hippo/YAP signaling were assessed by western blotting and immunofluorescence. Membrane receptors inhibitors, pathway inhibitors, lentiviral infection, plasmids transfection and immunoprecipitation were used to explore the specific mechanism of melatonin. In vivo, the rat IDD model were constructed and melatonin was injected intraperitoneally to evaluate its therapeutical effect on IDD. We demonstrated that melatonin could alleviate the development of IDD in a rat model and reverse TNF-α–impaired metabolism of NP cells in vitro. Further investigation revealed that the protective effects of melatonin on NP cells mainly rely on MTNR1B, which subsequently activates Gαi2 protein. The activation of Gαi2 could upregulate the yes-associated protein (YAP) level, resulting in anabolic enhancement of NP cells. In addition, melatonin-mediated YAP upregulation increased the expression of IκBα and suppressed the TNF-α–induced activation of the NF-κB pathway, thereby inhibiting the catabolism of NP cells. Our results revealed that melatonin can reverse TNF-α–impaired metabolism of NP cells via the MTNR1B/Gαi2/YAP axis and suggested that melatonin can be used as a potential therapeutic drug in the treatment of IDD.
RNAi targeting TNF-alpha inhibits particle-induced inflammation and osteolysis. Over 1000,000 joint prostheses are implanted every year in the world. Aseptic joint loosening is a key factor that reduces the longevity of joint prosthesis. Prosthetic wear particles are thought to play a central role in the initiation and development of periprosthetic osteolysis, leading to aseptic loosening of prostheses. This study aims to investigate the effect of RNA interference (RNAi) targeting tumor necrosis factor-alpha (TNF-α) gene on particle-induced inflammation and osteolysis in macrophages in vitro and in vivo.Summary
Introduction
RNAi targeting p110β reduces TNF-alpha production and osteolysis in response to wear particles. Aseptic joint loosening is a key factor that reduces the life span of joint prosthesis. Prosthetic wear particles are thought to play a central role in the initiation and development of periprosthetic osteolysis, leading to aseptic loosening of prostheses. This study aims to explore the effect of p110β-targeted small interfering RNA (siRNA) and lentivirus on particle-induced inflammatory cytokine expression in murine macrophage.Summary
Introduction
