Objective. There is mounting evidence to suggest a vascular insult is responsible for Perthes' disease, and it is suggested that this may have long-term implications for the vascular health of affected individuals. This study sought to use ultrasound measures to investigate vascular structure and function in children affected by Perthes' disease. Material and Methods. This case control study encompassed 149 cases and 146 controls, frequency matched for age and sex. Endothelial function was measured using the technique of flow-mediated dilatation of the brachial artery, and alterations in arterial flow were recorded in response to an ischaemic stimulus. Results. There was a significant structural alteration in the vasculature amongst individuals with Perthes' disease (resting brachial artery diameter (cases 2.97mm vs. controls 3.11mm; p=0.01)), which remained even after adjusting for height. Additionally, there was a notable reduction in blood velocity (cases 33.84cm/sec vs controls 37.83cm/sec; p=0.01) and blood flow (cases 149.82ml/min vs. controls 184.67 ml/min; p=0.001), which was independent of baseline arterial size. There was no evidence to suggest that flow mediated dilatation of the brachial artery was impaired amongst affected individuals (p=0.71). Conclusion. Children with Perthes' disease exhibit small artery calibre and reduced function, which is independent of
