External adjuncts to enhance fracture healing: what is the role of ultrasound?

Current methods of fracture care use various adjuncts aimed at decreasing time to fracture union and improving fracture union rates. Among the most commonly used modalities, low-intensity pulsed ultrasound is emerging as a safe, cost-effective and reliable treatment for both fresh fractures and fracture nonunions. Both in vivo and in vitro basic science studies have helped to elucidate potential mechanisms of ultrasound action and a number of prospective, randomised, double-blind, placebo-controlled trials exist demonstrating the clinical efficacy of low-intensity pulsed ultrasound. This article will review the evidence for the use of low-intensity pulsed ultrasound in fracture care.