“…Very few studies have been published regarding the application of the ultrasound guidance for the psoas compartment block in adults [19]. Sonoanatomical studies have shown that it is possible to visualize the transverse processes, vertebral body, psoas major muscle, erector spinae, quadratus lumborum, lower pole of the kidney, peritoneum, aorta, and vena cava [20,21], whereas direct imaging of the nerve roots is not easy to reproduce because of their depth and the 'acoustic shadow' of the transverse processes [22 & ].…”