Contrast-enhanced ultrasound (CEUS) quantifies the perfusion within tibial non-unions and predicts the outcome of revision surgery

Introduction: Vascularity is one of the determining factors of successful bone regeneration. This prospective study focused on quantifying the microperfusion of tibial non-unions with contrast-enhanced ultrasound (CEUS) and comparing it to the outcome. Materials and Methods: 36 patients with tibial fracture non-unions received a CEUS examination 12 weeks after revision surgery and the osseous microperfusion was quantified. The osseous consolidation at a maximum of 24 months was assessed with standard x-rays and computed tomography. Results: 28 out of 36 non-unions (77.8%) showed consolidation, while 8 patients required further revision surgery. CEUS demonstrated significantly higher perfusion in consolidated vs. persistent non-unions for all quantification parameters (e.g.: Wash-in Perfusion Index (WiPI) p = 0.036). The Receiver Operating Characteristics (ROC) analysis revealed a sensitivity/specificity of 82.1%/75.0% with a WiPI cut-off at 19.9 a.u. for diagnosing persisting non-unions. Discussion: More than one year ahead of the final radiologic diagnostic examination, CEUS could predict eventual consolidation based on the osseous perfusion as soon as 12 weeks postoperatively. This information can be crucial for the decision making process of re-revision at an early stage.