The Role of Contrast-enhanced Ultrasound in the Femoral Head Perfusion Evaluation: A Pilot Study

We explored the value of contrast-enhanced ultrasound (CEUS) in evaluating femoral head (FH) perfusion, guiding interventions and follow-up for infants with developmental dysplasia of the hip (DDH) and septic arthritis of the hip (SAH). The aim was to provide robust evidence for clinical assessment. Ten infants, including 7 with DDH and 3 with SAH, were prospectively enrolled, with their bilateral hips alternately scanned during the CEUS exams. Twenty hips were classified into the case group (n = 11) and the control group (n = 9). Pre- and post-interventional studies were performed in DDH infants requiring interventions. FH perfusion was assessed by the perfusion area ratio (PAR) and quadrant location of microbubble-defect regions. In the case group, 25 CEUS studies were conducted, including 11 baseline, 7 follow-up and 7 post-intervention studies. The PAR significantly decreased in the case group (49.79% vs. 100.00%, p < 0.05). The microbubble-defect regions averagely affected 2 quadrants, primarily quadrat No. 3 (30%) and No. 4 (32%). Seven hip abduction angle adjustments were made based on pre-interventional studies, resulting in a significant increase in PAR in post-interventional studies (37.63% vs. 60.24%, p < 0.05). PAR increased in follow-up studies compared to baseline values (45.61% vs. 76.07%, p < 0.05). The inter- and intra-observer reproducibility of PAR measurements were excellent (intraclass correlation coefficient, both 0.97). CEUS proves to be a promising technique for quantitatively detecting FH perfusion in DDH and SAH infants with high reproducibility. It is valuable for baseline, intra-intervention and follow-up studies, aiming in clinical conditions and therapeutic effect evaluation.