Role of magnetic resonance imaging in entrapment and compressive neuropathy--what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: part 2. Upper extremity.
The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions, but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the upper extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the upper extremity are as follows: the brachial plexus of the thoracic outlet; axillary nerve of the quadrilateral space; radial nerve of the radial tunnel; ulnar nerve of the cubital tunnel and Guyon's canal; median nerve of the pronator syndrome, anterior interosseous nerve syndrome, and carpal tunnel syndrome. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging.
Department of Diagnostic Radiology, College of Medicine, Yonsei University, 134, Shinchondong, Seodaemun-ku, 120-752 Seoul, South Korea.
Sungjun
S
Kim
Jin-Young
JY
Choi
Yong-Min
YM
Huh
Ho-Taek
HT
Song
Sung-Ah
SA
Lee
Seung Min
SM
Kim
Jin-Suck
JS
Suh
D020516:Brachial Plexus Neuropathies / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D020422:Mononeuropathies / Q000473:pathology*; D009141:Musculoskeletal System / Q000294:innervation*; D009408:Nerve Compression Syndromes / Q000473:pathology*; D012540:Scapula / Q000294:innervation; D034941:Upper Extremity / Q000294:innervation* / Q000473:pathology*