Abstract
<title>Abstract</title> <p>Osteoporotic fractures (OPFs) exhibit impaired healing and progressive bone loss. Although moderate static magnetic fields (MMFs; 1 mT–1 T) have shown potential to regulate bone metabolism, their effects on OPF healing remain unclear. Here, we investigated the effects of MMF exposure on OPF healing and iron metabolism in OVX mice. An OVX-induced OPF model was established, and mice were exposed to 0.05–0.5 T MMF after tibial fracture. Fracture healing and bone loss were evaluated by micro-computed tomography, histological analysis, biomechanical testing, and serum biochemical assays on day 14 and 28 post-fracture. Iron contents in fracture callus, femur, and liver were determined using atomic absorption spectrometry. The results showed that MMF exposure significantly bone mineral density (BMD), improved mechanical properties, and expanded the mineralized area at the callus site in OVX mice. MMF exposure also increased osteoblast distribution and decreased osteoclast distribution at the callus site. Furthermore, MMF alleviated OVX-induced deterioration of the microarchitecture and mechanical properties of lumbar vertebrae and non-fractured tibiae, accompanied by increased serum levels of the N-terminal propeptide of type I procollagen (P1NP) and decreased levels of the β-isomer of C-terminal telopeptide of type I collagen (β-CTX). In addition, MMF regulated iron metabolism by reducing iron accumulation in fracture callus and femur and modulating serum ferritin levels during OPF healing. In conclusion, 0.05–0.5 T MMF exposure promotes OPF healing and alleviates systemic post-fracture bone loss in OVX mice and is associated with the regulation of iron metabolism, suggesting its potential as a non-invasive adjunctive therapy for OPF treatment.</p>