Therapeutic Research

Abstract

Background：Randomized trials and large‒scale studies have shown that low‒intensity pulsed ultrasound（LIPUS）effectively accelerates fracture healing, but many of those studies have focused on simple fractures or fractures that can be treated conservatively. Few studies have investigated LIPUS technology in open and comminuted fractures, which are particularly at risk of delayed healing. 　Object：This study investigated whether LIPUS accelerates radiographic healing in such patients. Method：This multicenter retrospective cohort study considered data from 343 patients at 37 clinics and hospitals across Japan. Eligible patients underwent surgery for open or comminuted tibial fracture between April 2007 and September 2010. The primary endpoint was time to radiographic healing after definitive fixation. 　Results：When time to start of LIPUS treatment was not considered, time to fracture healing was shorter in the non‒LIPUS group（n＝191） than the LIPUS group（n＝152）. Subanalysis by treatment timing showed that patients who started LIPUS early（within 21 days after surgery, n＝103）healed more quickly than other patients, although the between‒group difference was not statistically significant（p＝0.07）. Subanalysis by surgery type showed significantly shorter time to fracture healing for plate fixation in　patients who started LIPUS early（p＜0.001）. No significant difference was noted in patients treated with an intramedullary rod（p＝0.89）. 　Conclusion：If time to initial LIPUS treatment was not considered, fractures healed faster in the non‒LIPUS group than the LIPUS group. However, exploratory analysis suggests that LIPUS treatment may accelerate fracture healing if started soon after surgery, particularly in cases of plate fixation. Further research is needed.