Exposure to electromagnetic energy has potent signalling effects upon articular cells including chondrocytes, synoviocytes and osteoblasts. Attention has focused on two actions – the altered synthesis of cytokines and enzymes, and the enhanced synthesis of bone and cartilage extracellular matrix (ECM) molecules. In vitro studies with human and bovine articular cartilage have shown increased aggregcan synthesis, glycosaminoglycan content, and biomechanical aggregate modulus with EMF exposure. Osteoarthritic (OA) cartilage responds similarly depending upon the severity of the OA with early OA cartilage responding more robustly. On these bases, two in vivo studies have been done with the Dunkin-Hartley guinea pig model of spontaneous OA. Both studies demonstrated preservation of ECM with increased aggrecan synthesis, matrix glycosaminoglycan and type 2 collagen content, and reduced histological-histochemical (Mankin) scores. Suppression of matrix metalloproteases and IL-1, together with increased TGFb were also observed. Responses to various EMF configurations, in terms of amplitude, frequency, and exposure duration have been described, indicating dose responsiveness. These studies suggest the conclusion that exposure to specific EMFs reduce the progression of early OA. A randomized clinical trial is underway. EMFs may be a disease-modifying therapy for OA, resulting in maintenance of ECM and improvement in the cytokine environment of OA joints

The purine nucleoside, adenosine regulates functions in every tissue and organ in the body acting via four G-protein-coupled receptors, A. 1. , A. 2A. , A. 2B. , and A. 3. adenosine receptors (ARs). Electromagnetic field (EMF) stimulation is an innovative therapeutic technique able to increase cellular anabolic activity and limit the catabolic effects of inflammatory cytokines. The mechanisms of cell reception of EMFs are not well known and much research activity has focused on the interactions between EMFs and membrane receptors. Interestingly, links have been found between ARs and their modulation by such physical agents as pulsed EMFs. EMF exposure mediates a significant upregulation of A. 2A. and A. 3. ARs in chondrocytes, synoviocytes and osteoblasts, leading to the reduction of synthesis and release of pro-inflammatory cytokines. In cultured full-thickness cartilage explants, pulsed EMFs preserve the integrity of the extracellular matrix and antagonize the effect of catabolic cytokines, such as IL-1. Pulsed EMFs, through the increase of ARs, enhance the working efficiency of adenosine without the side effects, desensitization, and receptor down-regulation often related to the use of agonist drugs. Modulation of adenosine receptors by pulsed EMFs could be a mechanism of cell reception of EMFs and an innovative physiologic alternative to the use of adenosine agonists

The October 2014 Wrist & Hand Roundup360 looks at: pulsed electromagnetic field of no use in acute scaphoid fractures; proximal interphalangeal joint replacement: one at a time or both at once; trapeziometacarpal arthrodesis in the young patient; Tamoxifen and Dupytren’s disease; and endoscopic or open for de Quervain’s syndrome?

Objectives. Electromagnetic fields (EMF) are widely used in musculoskeletal disorders. There are indications that EMF might also be effective in the treatment of osteoporosis. To justify clinical follow-up experiments, we examined the effects of EMF on bone micro-architectural changes in osteoporotic and healthy rats. Moreover, we tested the effects of EMF on fracture healing. Methods. EMF (20 Gauss) was examined in rats (aged 20 weeks), which underwent an ovariectomy (OVX; n = 8) or sham-ovariectomy (sham-OVX; n = 8). As a putative positive control, all rats received bilateral fibular osteotomies to examine the effects on fracture healing. Treatment was applied to one proximal lower leg (three hours a day, five days a week); the lower leg was not treated and served as a control. Bone architectural changes of the proximal tibia and bone formation around the osteotomy were evaluated using in vivo microCT scans at start of treatment and after three and six weeks. Results. In both OVX and sham-OVX groups, EMF did not result in cancellous or cortical bone changes during follow-up. Moreover, EMF did not affect the amount of mineralised callus volume around the fibular osteotomy. Conclusions. In this study we were unable to reproduce the strong beneficial findings reported by others. This might indicate that EMF treatment is very sensitive to the specific set-up, which would be a serious hindrance for clinical use. No evidence was found that EMF treatment can influence bone mass for the benefit of osteoporotic patients. Cite this article: Bone Joint Res 2014;3:230–5