The Ulnar Nerve - Nerve Imaging Atlas


	Head and Neck

	Vagus (X)

	Spinal Accessory Nerve (XI)

	Cervical Plexus (C2-4)

	Brachial Plexus (C5-T1)

	Upper Extremity

	Musculocutaneous

	Radial

	Median

	Ulnar

	Lower Extremity

	Ilioinguinal / Iliohypogastric

	Femoral

	Sciatic

	Common Peroneal

	Tibial

	Sural

	The Ilioinguinal Nerves The lower abdominal wall is primarily innervated by four peripheral nerves: the subcostal nerve, ilioinguinal nerve, iliohypogastric nerve, and genitofemoral nerve. The first three nerves emerge between the transversus abdominis, internal oblique, and external oblique muscle layers. The most extended course of the nerves through abdominal wall is in the layer between the transversus and the internal oblique muscles. The Ilioinguinal Nerves in the Lower Abdomen (supine) The ilioinguinal nerves are small nerves that are best imaged when between the internal oblique and transversus muscles in the lower abdomen (Video 300 KB).

	(Roll cursor over image to see labels.) To image these nerves, place the transducer between the anterior superior iliac spine (ASIS) and the umbilicus (so that the active face of the transducer lies on the line connecting the ASIS and the umbilicus). Rock the transducer so that the inner shelf of ilium bone is imaged. The ilioinguinal nerves are often accompanied by blood vessels.

	More proximal imaging superior to the anterior iliac spine often yields excellent definition of the muscle layers and identification of both the iliohypogastric and ilioinguinal nerves between the internal oblique and transversus (Video 300 KB).

	(Roll cursor over image to see labels.) References Willschke H, Marhofer P, Bosenberg A, Johnston S, Wanzel O, Cox SG, Sitzwohl C, Kapral S. Ultrasonography for ilioinguinal/iliohypogastric nerve blocks in children. Br J Anaesth. 2005 Aug;95(2):226-30. Epub 2005 May 27. PMID: 15923270 Peer S, Bodner G: High-Resolution Sonography of the Peripheral Nervous System. Berlin, Springer Verlag, 2003. Eichenberger U, Greher M, Kirchmair L, Curatolo M, Moriggl B. Ultrasound-guided blocks of the ilioinguinal and iliohypogastric nerve: accuracy of a selective new technique confirmed by anatomical dissection. Br J Anaesth. 2006 May 12. PMID: 16698865

The Ilioinguinal Nerves