Pitfalls preventing bone union with EXOGEN Low-Intensity Pulsed Ultrasound

Objectives: To evaluate the efficacy of EXOGEN in achieving union and common pitfalls in its use within the Manchester Foundation Trust (MFT) and Salford Royal Foundation Trust (SRFT). Method: Patients receiving EXOGEN therapy between 01/01/2017 and 31/12/2019 at hospitals within MFT and SRFT were identified using EXOGEN logbooks and hospital IT systems. An equal number of patients were included from both sites. Data were retrospectively collected from clinical documents detailing clinical presentation comorbidities, and radiographic images, determining the radiological union post EXOGEN therapy. In addition, local practices were observed and compared to EXOGEN’s standardized guidance for clinicians. Results: Fifty-eight patients were included in the primary review, with 9 subsequently excluded based on insufficient clinical data. 47% of patients achieved radiological union following completion of EXOGEN therapy. Outcomes of the 23 patients with persistent non-union were as follows – 18 were referred for revision surgery, 5 were prescribed further EXOGEN therapy, 2 refused or were unfit for further intervention, and 1 did not have a plan documented. No significant baseline differences were present in both outcome groups. However, at MFT and SRFT, rates of union with EXOGEN are below that previously published in the literature. Conclusion: EXOGEN has proven successful in facilitating union in established cases of non-union without the risk and cost associated with revision surgery. Centre outcome differences may be explained by failure to educate clinicians and patients on the correct use of the EXOGEN device, failure to standardize follow-up or monitor compliance, and must be addressed to improve current services.