Background and purpose: Low intensity pulsed ultrasound (LIPUS) has the potential to increase healing rate in lower limb fractures in patients who have been surgically treated. The purpose of this study was to compare the difference in fracture healing in lower limb fractures in patients managed surgically and with LIPUS treatment compared to the patients managed surgically only.

Relevence: Use of low intensity pulsed ultrasound in fracture healing of lower limb non-union fractures in physiotherapy is not cost effective.

Participants Methods and analysis: Ninety-four patients with lower limb fractures were selected from two state hospitals and randomly assigned to a LIPUS intervention group and a control group. Patients were treated with LIPUS for 20 minutes every second day for 20 days during their hospital stay and after discharge. Pearson chi-square test was used to analyse  changes in callus formation, cortical bridging, presence of the fracture gap and overall healing using per-protocol and intention to treat analysis at six, 12 and 18 weeks.

Results: The most prevalent fracture was on the femur in both the intervention (57.9%) and control (61.4%) groups. Per protocol analysis indicated that there was no significant difference in the rate of callus formation, cortical bridging and the reduction of the fracture gap between the intervention and control group at six, 12 and 18 weeks with ITT analysis confirming these results. Approximately 10% to 20% of the intervention group had  a higher percentage of callus formation at six weeks and better cortical bridging, and absence of the fracture gap at 12 and 18 weeks.

Conclusions and implications: Low intensity pulsed ultrasound increased the rate of callus formation and cortical bridging in healing of surgically treated fractures, but did not influence the rate of complete healing by 18 weeks. The low rate of healing at 18 weeks was influenced by the high loss to follow up and suggests surgically treated fractures may be slower to achieve overall healing.

Keywords: lower limb fractures, LIPUS, callus formation

Funding: Enraf Mediotronics

Ethics: Clearance and approval from the Human Resource Ethics Committee at the University of the Witwatersrand (M150236) and University of Pretoria (349/2017) was granted.