Nerve Imaging Atlas
The objective of this atlas is to describe the characteristic features that identify peripheral nerves using ultrasound imaging.
The goals are to illustrate key anatomic features of peripheral nerves that can be identified with ultrasound imaging. This includes the best acoustic windows, optimal angles of insonation, characteristic dynamic motion and consistent associated structures. Although nerves can be imaged anywhere along their course, this atlas will provide a starting point for identifying normal nerve anatomy. We hope to promote nerve imaging with ultrasound for clinical practice, teaching and research.
The scope of the atlas includes all peripheral and cranial nerves with reported sonographic imaging (exceptions: recurrent laryngeal nerve, pudendal nerve, and optic nerve)
The Vagus Nerve in the Cervical Region (supine with head turned towards the opposite side)
The cervical vagus nerve is about 2 mm in diameter and honeycomb in sonographic appearance. The vagus nerve is often triangle shaped as it is wedged between the internal jugular vein and carotid artery in the lower neck:
(Roll cursor over image to see labels.)
The vagus nerve lies in the posterior angle formed between the internal jugular vein and the carotid artery (Giovagnorio and Martinoli, 2001). Location of the vagus nerve in the anterior angle is rare (0.7% of healthy subjects, Giovagnorio and Martinoli, 2001). In some subjects the vagus nerve will cross in front of the carotid artery.
References
Giovagnorio F, Martinoli C. Sonography of the cervical vagus nerve: normal appearance and abnormal findings. AJR Am J Roentgenol. 2001 Mar;176(3):745-9. PMID: 11222217
Knappertz VA, Tegeler CH, Hardin SJ, McKinney WM. Vagus nerve imaging with ultrasound: anatomic and in vivo validation. Otolaryngol Head Neck Surg. 1998 Jan;118(1):82-5. PMID: 9450833
Solbiati L, De Pra L, Ierace T, Bellotti E, Derchi LE. High-resolution sonography of the recurrent laryngeal nerve: anatomic and pathologic considerations. AJR Am J Roentgenol. 1985 Nov;145(5):989-93. PMID: 3901711
Silvestri E, Martinoli C, Derchi LE, Bertolotto M, Chiaramondia M, Rosenberg I. Echotexture of peripheral nerves: correlation between US and histologic findings and criteria to differentiate tendons. Radiology. 1995 Oct;197(1):291-6. PMID: 7568840
The spinal accessory nerve (cranial nerve XI) provides motor innervation of the sternocleidomastoid and trapezius muscles with essentially no sensory component. The nerve emerges under the sternocleidomastoid muscle to lie on the levator scapulae and middle scalene muscles ventral to the anterior border of the trapezius muscle. Variations in the course and surface landmarks of the nerve have led investigators to study its sonographic anatomy. Because of its superficial location near lymph nodes, the spinal accessory nerve can be injured during cervical lymph node biopsy.
The spinal accessory nerve is among the smallest nerves imaged with ultrasound, with a transverse diameter of about one mm and monofascicular in sonographic appearance:
(Roll cursor over image to see labels.)
References
Bodner G, Harpf C, Gardetto A, Kovacs P, Gruber H, Peer S, Mallhoui A. Ultrasonography of the accessory nerve: normal and pathologic findings in cadavers and patients with iatrogenic accessory
The nerves of the superficial cervical plexus provide sensory innervation to the ear, neck and clavicle. All the nerves of the superficial cervical plexus emerge along the lateral border of the sternocleidomastoid muscle. The cervical plexus can be identified using the interscalene groove as a guide. To do so, slide the ultrasound probe cephalad with the brachial plexus viewed in short axis.
The greater auricular nerve (GAN) from the superficial cervical plexus lies on the sternocleidomastoid muscle just posterior to the external jugular vein. The spinal accessory nerve has a similar course but lies deep to the sternocleidomastoid muscle.
(Roll cursor over image to see labels.)
References
Sheppard DG, Iyer RB, Fenstermacher MJ. Brachial plexus: demonstration at US. Radiology. 1998 Aug;208(2):402-6. PMID: 9680567
Yang WT, Chui PT, Metreweli C. Anatomy of the normal brachial plexus revealed by sonography and the role of sonographic guidance in anesthesia of the brachial plexus. AJR Am J Roentgenol. 1998 Dec;171(6):1631-6. PMID: 9843302
Martinoli C, Bianchi S, Santacroce E, Pugliese F, Graif M, Derchi LE. Brachial plexus sonography: a technique for assessing the root level. AJR Am J Roentgenol. 2002 Sep;179(3):699-702. PMID: 12185049
Demondion X, Herbinet P, Boutry N, Fontaine C, Francke JP, Cotten A. Sonographic mapping of the normal brachial plexus. AJNR Am J Neuroradiol. 2003 Aug;24(7):1303-9. PMID: 12917117
Eichenberger U, Greher M, Kapral S, Marhofer P, Wiest R, Remonda L, Bogduk N, Curatolo M. Sonographic visualization and ultrasound-guided block of the third occipital nerve: prospective for a new method to diagnose C2-C3 zygapophysial joint pain. Anesthesiology. 2006 Feb;104(2):303-8. PMID: 16436850
The Brachial Plexus in the Cervical Region (supine with neck turned to opposite side)
The brachial plexus emerges between the scalene muscles in the neck and joins the subclavian artery as it lies above the first rib. The tapering lateral edge of the sternocleidomastoid muscle lies over the brachial plexus. The brachial plexus and scalene muscles are covered by the prevertebral fascia. In contrast to more peripheral nerves, the cervical roots (ventral rami) often have a monofascicular appearance.
(Roll cursor over image to see labels.)
The Brachial Plexus above the First Rib
The brachial plexus can be identified just superficial and lateral to the subclavian artery in the neck. The brachial plexus can be traced between the scalene muscles and more cephalad to show higher cervical roots. The interconnections of the brachial plexus can sometimes be identified using short axis slides:
In some subjects the cephalad elements of the brachial plexus (such as the C5 and/or C6 ventral rami) pass through or over the anterior scalene muscle rather than between the anterior and middle scalene muscles:
(Roll cursor over image to see labels.)
References
Sheppard DG, Iyer RB, Fenstermacher MJ. Brachial plexus: demonstration at US. Radiology. 1998 Aug;208(2):402-6. PMID: 9680567
Yang WT, Chui PT, Metreweli C. Anatomy of the normal brachial plexus revealed by sonography and the role of sonographic guidance in anesthesia of the brachial plexus. AJR Am J Roentgenol. 1998 Dec;171(6):1631-6. PMID: 9843302
Martinoli C, Bianchi S, Santacroce E, Pugliese F, Graif M, Derchi LE. Brachial plexus sonography: a technique for assessing the root level. AJR Am J Roentgenol. 2002 Sep;179(3):699-702. PMID: 12185049
Demondion X, Herbinet P, Boutry N, Fontaine C, Francke JP, Cotten A. Sonographic mapping of the normal brachial plexus. AJNR Am J Neuroradiol. 2003 Aug;24(7):1303-9. PMID: 12917117
Harry WG, Bennett JD, Guha SC. Scalene muscles and the brachial plexus: anatomical variations and their clinical significance. Clin Anat. 1997;10(4):250-2. PMID: 9213042
The Musculocutaneous Nerve in the Arm (supine with arm abducted)
The musculocutanous nerve has a characteristic lateral course and flat shape as it passes through the coracobrachialis muscle in the arm. After exiting the coracobrachialis muscle the musculocutaneous nerve assumes a triangular shape:
(Roll cursor over image to see labels.)
The musculocutaneous nerve is a relatively flat, straight nerve that can be seen in long axis when it passes through the coracobrachialis muscle. The coracobrachialis muscle is most reliably identified by sliding the transducer from distal to proximal starting at the mid-humeral level with the brachial artery and humerus in the imaging field of view. The coracobrachialis has a doming appearance when viewed in short axis.
In some arms (8-30%) the musculocutaneous nerve will pass over the coracobrachialis muscle rather than passing through it. Interestingly, in these arms the musculocutaneous nerve undergoes a similar shape change, probably because the short head of the biceps plays a similar mechanical role as the coracobrachialis muscle in shaping the nerve.
References
Schafhalter-Zoppoth I, Gray AT. The musculocutaneous nerve: ultrasound appearance for peripheral nerve block. Reg Anesth Pain Med. 2005 Jul-Aug;30(4):385-90. PMID: 16032591
The Radial Nerve
The radial nerve arises from the posterior cord of the brachial plexus. The radial nerve innervates the extensor-supinator muscle group and provides sensory innervation to the posterior aspect of the elbow, forearm and hand.
The Radial Nerve in the Arm (supine with arm abducted)
The radial nerve leaves the axillary artery with the profunda brachii artery in the axilla to innervate the triceps muscle. The profunda brachii artery follows the radial nerve as it moves from the axillary artery towards the spiral groove of the humerus. Because the radial nerve travels in the spiral groove of the humerus it can be damaged with these fractures:
(Roll cursor over image to see labels.)
The radial nerve divides into its superficial and deep branches on the lateral side of the antecubital fossa. The radial nerve lies over the lateral epicondyle of the humerus:
The Superficial Radial Nerve in the Forearm (supine with arm supinated)
The superficial radial nerve joins the radial artery in the middle third of the forearm. The SRN joins and leaves the radial artery on its lateral side. The superficial radial nerve divides approximately 5 cm proximal to the styloid process of the radius:
(Roll cursor over image to see labels.)
References
Martinoli C, Bianchi S, Pugliese F, Bacigalupo L, Gauglio C, Valle M, Derchi LE. Sonography of entrapment neuropathies in the upper limb (wrist excluded). J Clin Ultrasound. 2004 Nov-Dec;32(9):438-50. Review. PMID: 15558622
Bianchi S, Montet X, Martinoli C, Bonvin F, Fasel J. High-resolution sonography of compressive neuropathies of the wrist. J Clin Ultrasound. 2004 Nov-Dec;32(9):451-61. PMID: 15558623
Chien AJ, Jamadar DA, Jacobson JA, Hayes CW, Louis DS. Sonography and MR imaging of posterior interosseous nerve syndrome with surgical correlation. AJR Am J Roentgenol. 2003 Jul;181(1):219-21. PMID: 12818863
Loewy J. Sonoanatomy of the median, ulnar and radial nerves. Can Assoc Radiol J. 2002 Feb;53(1):33-8. Review. PMID: 11882990
Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990
Bodner G, Harpf C, Meirer R, Gardetto A, Kovacs P, Gruber H. Ultrasonographic appearance of supinator syndrome. J Ultrasound Med. 2002 Nov;21(11):1289-93. PMID: 12418768
Bodner G, Huber B, Schwabegger A, Lutz M, Waldenberger P. Sonographic detection of radial nerve entrapment within a humerus fracture. J Ultrasound Med. 1999 Oct;18(10):703-6. PMID: 10511303
Bodner G, Buchberger W, Schocke M, Bale R, Huber B, Harpf C, Gassner E, Jaschke W. Radial nerve palsy associated with humeral shaft fracture: evaluation with US--initial experience. Radiology. 2001 Jun;219(3):811-6. PMID: 11376275
Ikiz ZA, Ucerler H. Anatomic characteristics and clinical importance of the superficial branch of the radial nerve. Surg Radiol Anat. 2004 Dec;26(6):453-8. PMID: 15365770
The Median Nerve
The ultrasound appearance of the median nerve has been extensively described in the carpal tunnel syndrome literature. The median nerve arises from the medial and lateral cords of the brachial plexus.
The Median Nerve in the Arm (supine with arm abducted)
The median nerve usually lies superficial to the axillary artery in the axilla. The median crosses the front of the artery from lateral to medial and can be displaced to either side of the axillary artery with transducer compression:
The Median Nerve in the Forearm (supine with arm supinated)
The median nerve lies of the medial side of the brachial artery near the antecubital fossa. The median nerve leaves the brachial artery or ulnar artery to enter the forearm.
In the forearm the median nerve lies in the fascia between the flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) muscles. Around 5 cm proximal to the flexor retinaculum, the median nerve courses around the lateral edge of the FDS (Jamadar et al., 2001) and over the pronator quadratus. This is where the median nerve is usually brightest (Jamadar et al., 2001):
(Roll cursor over image to see labels.)
While the median artery normally evolutes during development, persistent median artery can be detected with high-resolution ultrasound in about 25% of asymptomatic individuals. Persistent median artery is sometimes associated with high division or bifid median nerve:
References
Gassner EM, Schocke M, Peer S, Schwabegger A, Jaschke W, Bodner G. Persistent median artery in the carpal tunnel: color Doppler ultrasonographic findings. J Ultrasound Med. 2002 Apr;21(4):455-61. PMID: 11934102
Jamadar DA, Jacobson JA, Hayes CW. Sonographic evaluation of the median nerve at the wrist. J Ultrasound Med. 2001 Sep;20(9):1011-4. PMID: 11549149
Propeck T, Quinn TJ, Jacobson JA, Paulino AF, Habra G, Darian VB. Sonography and MR imaging of bifid median nerve with anatomic and histologic correlation. AJR Am J Roentgenol. 2000 Dec;175(6):1721-5. Review. PMID: 11090410
Retzl G, Kapral S, Greher M, Mauritz W. Ultrasonographic findings of the axillary part of the brachial plexus. Anesth Analg. 2001 May;92(5):1271-5. PMID: 11323361
Iannicelli E, Chianta GA, Salvini V, Almberger M, Monacelli G, Passariello R. Evaluation of bifid median nerve with sonography and MR imaging. J Ultrasound Med. 2000 Jul;19(7):481-5. PMID: 10898302
Walker FO, Cartwright MS, Wiesler ER, Caress J. Ultrasound of nerve and muscle. Clin Neurophysiol. 2004 Mar;115(3):495-507. Review. PMID: 15036045
Bianchi S, Montet X, Martinoli C, Bonvin F, Fasel J. High-resolution sonography of compressive neuropathies of the wrist. J Clin Ultrasound. 2004 Nov-Dec;32(9):451-61. PMID: 15558623
Martinoli C, Bianchi S, Pugliese F, Bacigalupo L, Gauglio C, Valle M, Derchi LE. Sonography of entrapment neuropathies in the upper limb (wrist excluded). J Clin Ultrasound. 2004 Nov-Dec;32(9):438-50. Review. PMID: 15558622
Chen P, Maklad N, Redwine M, Zelitt D. Dynamic high-resolution sonography of the carpal tunnel. AJR Am J Roentgenol. 1997 Feb;168(2):533-7. Review. PMID: 9016242
The Ulnar Nerve
The ulnar nerve arises from the medial cord of the brachial plexus. In the arm the ulnar nerve usually lies between the axillary artery and axillary vein in the axilla.
The Ulnar Nerve in the Forearm (supine with arm supinated)
The ulnar nerve is a bright (echogenic) triangular or oval nerve distal to the elbow. The ulnar nerve joins the ulnar side of the ulnar artery in the forearm where it is surrounded by the flexor digitorum superficialis (FDS), flexor digitorum profundus (FDP) and flexor carpi ulnaris (FCU) muscles. In the distal forearm the ulnar nerve will lie adjacent to the FCU tendon:
(Roll cursor over image to see labels.)
Palmar and dorsal cutaneous branches of the nerves to the hand are given off proximal to the wrist (especially the dorsal cutaneous branch of the ulnar nerve. A relatively common (3-10%) anatomic variant is superficial ulnar artery, where the ulnar artery instead lies superficial to the flexor muscles:
References
Gray AT, Schafhalter-Zoppoth I. Ultrasound guidance for ulnar nerve block in the forearm. Reg Anesth Pain Med. 2003 Jul-Aug;28(4):335-9. PMID: 12945028
Schafhalter-Zoppoth I, Gray AT. Ultrasound-guided ulnar nerve block in the presence of a superficial ulnar artery. Reg Anesth Pain Med. 2004 May-Jun;29(3):297-8. PMID: 15138917
Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990
Peeters EY, Nieboer KH, Osteaux MM. Sonography of the normal ulnar nerve at Guyon's canal and of the common peroneal nerve dorsal to the fibular head. J Clin Ultrasound. 2004 Oct;32(8):375-80. PMID: 15372443
Jacob D, Creteur V, Courthaliac C, Bargoin R, Sassus B, Bacq C, Rozies JL, Cercueil JP, Brasseur JL. Sonoanatomy of the ulnar nerve in the cubital tunnel: a multicentre study by the GEL. Eur Radiol. 2004 Oct;14(10):1770-3. PMID: 15258824
Peer S, Bodner G (editors). High-Resolution Sonography of the Peripheral Nervous System. Springer Verlag, 2003. ISBN: 3540432604.
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:
(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:
(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 Femoral Nerve
The femoral nerve is triangular or oval in transverse cross-section as it lies in the groove between the iliacus and psoas muscles near the inguinal crease. The fascia iliaca covers both the nerve and muscle. The femoral nerve fascicles disperse as the nerve divides into many branches over the anterior thigh:
(Roll cursor over image to see labels.)
References
Sener RN, Alper H, Ozturk L, Ozer H, Falakali S. Retroperitoneal part of the femoral nerve. Normal ultrasound features. Neuroradiology. 1991;33(2):159-61. PMID: 2046903
Gruber H, Peer S, Kovacs P, Marth R, Bodner G. The ultrasonographic appearance of the femoral nerve and cases of iatrogenic impairment. J Ultrasound Med. 2003 Feb;22(2):163-72. PMID: 12562121
Gray AT, Collins AB, Schafhalter-Zoppoth I. An introduction to femoral nerve and associated lumbar plexus nerve blocks under ultrasonic guidance. Techniques in Regional Anesthesia and Pain Management 2004; 8:155-63. (video component online at the journals website)
Soong J, Schafhalter-Zoppoth I, Gray AT. The importance of transducer angle to ultrasound visibility of the femoral nerve. Reg Anesth Pain Med. 2005 Sep-Oct;30(5):505. PMID: 16135356
The Sciatic Nerve
The Sciatic Nerve in the Thigh (prone)
The sciatic nerve lies lateral to the tendinous origin of the biceps femoris in the proximal thigh. The sciatic nerve and proximal tendon of the biceps femoris muscle can be similar in sonographic appearance.
(Roll cursor over image to see labels.)
The sciatic nerve divides into its common peroneal and tibial nerve components in the popliteal fossa:
(Roll cursor over image to see labels.)
As those latter two nerves form they emerge superficial to the underlying muscles. The tibial nerve is larger than the common peroneal nerve which has a more lateral course. Foot motion can change the position of the nerves in this region. This seesaw sign is very useful for determining whether the common peroneal nerve is indeed part of the common sciatic nerve in the popliteal fossa near the division of the nerve.
References
Hoddick WK, Callen PW, Filly RA, Mahony BS, Edwards MB. Ultrasound evaluation of benign sciatic nerve sheath tumors. J Ultrasound Med. 1984 Nov;3(11):505-7. PMID: 6439894
Fornage BD. Sonography of peripheral nerves of the extremities. Radiol Med (Torino). 1993 May;85(5 Suppl 1):162-7. Review. PMID: 8392740
Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990
Peer S, Kovacs P, Harpf C, Bodner G. High-resolution sonography of lower extremity peripheral nerves: anatomic correlation and spectrum of disease. J Ultrasound Med. 2002 Mar;21(3):315-22. PMID: 11883543
Graif M, Seton A, Nerubai J, Horoszowski H, Itzchak Y. Sciatic nerve: sonographic evaluation and anatomic-pathologic considerations. Radiology. 1991 Nov;181(2):405-8. PMID: 1924780
Grechenig W, Clement HG, Peicha G, Klein A, Weiglein A. [Ultrasound anatomy of the sciatic nerve of the thigh] Biomed Tech (Berl). 2000 Nov;45(11):298-303. German. PMID: 11155530
Silvestri E, Martinoli C, Derchi LE, Bertolotto M, Chiaramondia M, Rosenberg I. Echotexture of peripheral nerves: correlation between US and histologic findings and criteria to differentiate tendons. Radiology. 1995 Oct;197(1):291-6. PMID: 7568840
Gray AT, Collins AB, Schafhalter-Zoppoth I. Sciatic nerve block in a child: a sonographic approach. Anesth Analg. 2003 Nov;97(5):1300-2. PMID: 14570642
Gray AT, Huczko EL, Schafhalter-Zoppoth I. Lateral popliteal nerve block with ultrasound guidance. Reg Anesth Pain Med. 2004 Sep-Oct;29(5):507-9. PMID: 15372402
Schafhalter-Zoppoth I, Younger SJ, Collins AB, Gray AT. The "seesaw" sign: improved sonographic identification of the sciatic nerve. Anesthesiology. 2004 Sep;101(3):808-9. Erratum in: Anesthesiology. 2005 Jan;102(1):248. PMID: 15329621 (video component online at journals website Enhancements 2004)
Schwemmer U, Markus CK, Greim CA, Brederlau J, Trautner H, Roewer N. Sonographic imaging of the sciatic nerve and its division in the popliteal fossa in children. Paediatr Anaesth. 2004 Dec;14(12):1005-8. PMID: 15601350
Schwemmer U, Markus CK, Greim CA, Brederlau J, Kredel M, Roewer N. Sonographic imaging of the sciatic nerve division in the popliteal fossa. Ultraschall Med. 2005 Dec;26(6):496-500. PMID: 16453221
The Common Peroneal Nerve and its Branches
The Common Peroneal Nerve in the Leg (prone with ankle supported)
The common peroneal nerve is a branch of the sciatic nerve and lies on the medial side of the common (conjoint) tendon of the biceps femoris muscle at the popliteal crease. The peroneal nerves can be imaged in the prone position with the knee flexed using a pillow under the ankle. The common peroneal nerve winds laterally around the neck of the fibula and then pierces the peroneus longus muscle. The common peroneal nerve flattens in shape as it passes over the fibular neck . This proximity to bone makes it vulnerable to injury at that location:
(Roll cursor over image to see labels.)
Superficial Peroneal Nerve
The superficial branch of the common peroneal nerve innervates the peroneus longus and brevis muscles of the lateral compartment of the leg. The superficial peroneal nerve tracks along the fascia between the lateral and anterior compartments of the leg to emerge by piercing the fascia lata and enter the subcutaneous tissues (see video above).
Deep Peroneal Nerve
The deep peroneal nerve arises in the substance of the peroneus longus muscle and enters the anterior compartment after piercing the fascial septum. The deep peroneal nerve joins the anterior tibial artery in the anterior compartment of the leg.
References
Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990
Peeters EY, Nieboer KH, Osteaux MM. Sonography of the normal ulnar nerve at Guyon's canal and of the common peroneal nerve dorsal to the fibular head. J Clin Ultrasound. 2004 Oct;32(8):375-80. PMID: 15372443
Peer S, Kovacs P, Harpf C, Bodner G. High-resolution sonography of lower extremity peripheral nerves: anatomic correlation and spectrum of disease. J Ultrasound Med. 2002 Mar;21(3):315-22. PMID: 11883543
Gruber H, Peer S, Meirer R, Bodner G. Peroneal nerve palsy associated with knee luxation: evaluation by sonography--initial experiences. AJR Am J Roentgenol. 2005 Nov;185(5):1119-25. PMID: 16247119
The Tibial Nerve
The Tibial Nerve in the Leg (prone)
The tibial nerve is a continuation of the common sciatic nerve that provides almost all the sensory innervation of the plantar aspect of the foot. The tibial nerve is best imaged in the leg just distal to where the gastrocnemius muscles taper. The tibial nerve dives deep between the medial and lateral heads of the gastrocemius muscle to enter the leg:
The tibial nerve joins the posterior tibial artery in the leg. The nerve often meanders close to and away from the posterior tibial artery along its course. The tibial nerve lies on the posterior (heel) side of the posterior tibial artery in the leg. The normal neurovascular bundle consists of the tibial nerve, posterior tibial artery, and two posterior tibial veins in the leg. The medial calcaneal branch of the tibial nerve can often be seen with ultrasound imaging.
(Roll cursor over image to see labels.)
References
Fornage BD. Sonography of peripheral nerves of the extremities. Radiol Med (Torino). 1993 May;85(5 Suppl 1):162-7. Review. PMID: 8392740
Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990
Peer S, Kovacs P, Harpf C, Bodner G. High-resolution sonography of lower extremity peripheral nerves: anatomic correlation and spectrum of disease. J Ultrasound Med. 2002 Mar;21(3):315-22. PMID: 11883543
The Sural Nerve
The Sural Nerve in the Leg (prone)
Prior reports of ultrasound imaging of the sural nerve are limited. The sural nerve provides sensory innervation to the lateral aspect of the heel and foot and is sometimes used for nerve biopsy or harvest. The sural nerve usually forms from tibial (medial) and common peroneal (lateral) components, but anatomic variation is common.
A sural contribution from the tibial nerve can be imaged between the medial and lateral heads of the gastrocnemius muscles. The sural nerve emerges between these muscles to pierce the fascia lata and join the lesser saphenous vein within the subcutaneous tissue of the lateral aspect of the lower leg:
(Roll cursor over image to see labels.)
References
Simonetti S, Bianchi S, Martinoli C. Neurophysiological and ultrasound findings in sural nerve lesions following stripping of the small saphenous vein. Muscle Nerve. 1999 Dec;22(12):1724-6. PMID: 10567089
Solomon LB, Ferris L, Tedman R, Henneberg M. Surgical anatomy of the sural and superficial fibular nerves with an emphasis on the approach to the lateral malleolus. J Anat. 2001 Dec;199(Pt 6):717-23. PMID: 11787825
Coert JH, Dellon AL. Clinical implications of the surgical anatomy of the sural nerve. Plast Reconstr Surg. 1994 Nov;94(6):850-5. PMID: 7972432
* Gray AT. Ultrasound-guided Regional Anesthesia: Current State of the Art. Anesthesiology. 2006 Feb;104(2):368-73. This review summarizes the latest developments in the field of nerve imaging for ultrasound guided regional block.
Soong J, Schafhalter-Zoppoth I, Gray AT. The importance of transducer angle to ultrasound visibility of the femoral nerve. Reg Anesth Pain Med. 2005 Sep-Oct;30(5):505. This letter describes estimation of the anisotropy of the femoral nerve and its importance to femoral nerve block with ultrasound guidance.
Schafhalter-Zoppoth I, Gray AT. The musculocutaneous nerve: ultrasound appearance for peripheral nerve block. Reg Anesth Pain Med. 2005 Jul-Aug;30(4):385-90. This imaging article describes the characteristic lateral course and shape changes of the musculocutaneous nerve in the axilla. These observations have functional implications for peripheral block.
Gray AT. Role of ultrasound in startup regional anesthesia practice for outpatients. Int Anesthesiol Clin. 2005 Summer;43(3):69-78. This article critically reviews the role of ultrasound guidance in regional anesthesia procedures in an ambulatory care setting.
Gray AT, Huczko EL, Schafhalter-Zoppoth I. Lateral popliteal nerve block with ultrasound guidance. Reg Anesth Pain Med. 2004 Sep-Oct;29(5):507-9. In this letter the lateral in plane approach to popliteal block is described.
Schafhalter-Zoppoth I, McCulloch CE, Gray AT. Ultrasound visibility of needles used for regional nerve block: an in vitro study. Reg Anesth Pain Med. 2004 Sep-Oct;29(5):480-8. Needle tip visibility is of paramount importance for the success and safety of regional blocks with ultrasound guidance. This article reports visibility measurements under a variety of conditions relevant to regional block.
Schafhalter-Zoppoth I, Younger SJ, Collins AB, Gray AT. The 'seesaw' sign: improved sonographic identification of the sciatic nerve. Anesthesiology. 2004 Sep;101(3):808-9. Erratum in: Anesthesiology. 2005 Jan;102(1):248. This letter describes the use of nerve motion to enhance the identification of nerves of the lower extremity.
** Gray AT, Collins AB, Schafhalter-Zoppoth I. An introduction to femoral nerve and associated lumbar plexus nerve blocks under ultrasonic guidance. Techniques in Regional Anesthesia and Pain Management 2004; 8:155-63. (featured on the cover of the issue) (video component online at journal's website) This review describes approaches to lumbar plexus blockade using ultrasound imaging. The entire issue of this journal was dedicated to ultrasound guidance for regional blockade.
Schafhalter-Zoppoth I, Gray AT. Ultrasound-guided ulnar nerve block in the presence of a superficial ulnar artery. Reg Anesth Pain Med. 2004 May-Jun;29(3):297-8. Anatomic variation can be a source of difficulty for surface based approaches to regional block. This letter describes one common anatomic variant.
Gray AT, Collins AB, Schafhalter-Zoppoth I. Sciatic nerve block in a child: a sonographic approach. Anesth Analg. 2003 Nov;97(5):1300-2. This case report describes sonoanatomy of the sciatic nerve in the posterior thigh and relevant considerations for pediatric blocks. Although there were prior reports of the sonographic anatomy of the sciatic nerve, this described utilization of ultrasound for sciatic nerve block.
Gray AT, Schafhalter-Zoppoth I. Ultrasound guidance for ulnar nerve block in the forearm. Reg Anesth Pain Med. 2003 Jul-Aug;28(4):335-9. This imaging article describes sonographic and anatomic considerations for ulnar nerve block in the forearm. Many principles of neural imaging for regional block are discussed.
Gray AT, Collins AB. Ultrasound-guided saphenous nerve block. Reg Anesth Pain Med. 2003 Mar-Apr;28(2):148. This letter describes a new ultrasound guided approach to saphenous nerve block near the tibial tuberosity. This anesthetic procedure is highly important for surgical procedures about the ankle.
Director: Andrew T. Gray, M.D., Ph.D.
Producer: Adam B. Collins, M.D.
Editor: Ingeborg Schafhalter-Zoppoth, M.D.
Special Effects: Jens Kessler, M.D.
Production Specialist: David Mai, B.S.
Advisor: Brad Immanuel, B.A.
University of California, San Francisco
Department of Anesthesia, Room 3C-38
San Francisco General Hospital
1001 Potrero Avenue
San Francisco, California 94110
FAX: (415) 206-6014
Email: [email protected]