Fig 5. Transverse sonogram of the inner aspect of the proximal thigh 2 cm proximal to the inguinal crease showing the pectineus and obturator externus muscles and the obturator artery. (B) Annotated structures identified in (A). Abbreviations: P m., pectineus muscle; OE m., obturator externus muscle. Red circle: obturator artery within the intermuscular aponeurotic septum.