Keywords:
Education and training, Education, Ultrasound-Colour Doppler, Neuroradiology peripheral nerve, Musculoskeletal system, Anatomy
Authors:
G. Rebella1, E. Massone1, M. De Cesari1, G. Buonomenna1, S. Perugin Bernardi2, D. Orlandi2, A. Muda2, E. Silvestri1; 1Genoa/IT, 2Genova/IT
DOI:
10.26044/essr2019/P-0043
Imaging findings OR Procedure Details
Place the patient supine,
with the leg extended and slightly externally rotated.
Identify the anterior superior iliac spine (ASIS) and the pubic symphysis,
and draw an imaginary line between these two landmarks that represents the inguinal ligament.
Place the probe in the inguinal crease in a transverse plane,
across the femoral region of the upper thigh,
parallel to the inguinal ligament,
to identify the femoral vein and artery (Fig.
2 a,
Fig.
3 b).
At this level the iliopsoas and pectineus muscles can be clearly recognized.
If you cannot identify the vascular landmarks,
slide the probe medial to lateral until the femoral vessels are seen.
Compression with the probe is useful to identify the femoral vein: in fact the vein (medial) collapses more easily than the artery (lateral).
Color Doppler module can be used to confirm the identification of the femoral vessels (Fig.
2 a,
Fig.
3 c).
The femoral nerve lies about 1–2 cm lateral to the artery,
below fascia iliaca and lata and above the iliopsoas muscle,
and appears as a triangular or oval honeycomb structure 3–10 mm in diameter covered anteriorly by the hyperechoic fascia iliaca.
If the femoral nerve appears hypoechoic due to anisotropy artifacts,
slightly tilt the probe cranially or caudally to correctly visualize the nerve.
Then,
turn the transducer by 90° to identify the nerve in a longitudinal plane.