Low-magnitude high-frequency vibration enhances gene expression related to callus formation, mineralization and remodeling during osteoporotic fracture healing in rats.

Low magnitude high frequency vibration (LMHFV) has been shown to improve anabolic and osteogenic responses in osteoporotic intact bones and during osteoporotic fracture healing; however, the molecular response of LMHFV during osteoporotic fracture healing has not been investigated. It was hypothesized that LMHFV could enhance osteoporotic fracture healing by regulating the expression of genes related to chondrogenesis (Col-2), osteogenesis (Col-1) and remodeling (receptor activator for nuclear factor- κ B ligand (RANKL) and osteoproteger (OPG)). In this study, the effects of LMHFV on both osteoporotic and normal bone fracture healing were assessed by endpoint gene expressions, weekly radiographs, and histomorphometry at weeks 2, 4 and 8 post-treatment.

Fracture healing enhancement with low intensity pulsed ultrasound at a critical application angle.

Low-intensity pulsed ultrasound (LIPUS) was shown to have dose-dependent enhancement effect on the osteogenic activity of human periosteal cells that played an important role in fracture healing. It was hypothesized that the stimulatory effects of LIPUS on the periosteal cells could be optimized by adjusting the ultrasound delivered at its critical angle to the surface of bone. This increased the transmission of ultrasound waves on periosteum.