Semin Musculoskelet Radiol 2010; 14(5): 473-486
DOI: 10.1055/s-0030-1268068
© Thieme Medical Publishers

Entrapment Neuropathies I: Upper Limb (Carpal Tunnel Excluded)

Jon A. Jacobson1 , David P. Fessell1 , Lucas Da Gama Lobo1 , Lynda J.-S. Yang2
  • 1Department of Radiology, University of Michigan, Ann Arbor, Michigan
  • 2Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
Further Information

Publication History

Publication Date:
11 November 2010 (online)


Several entrapment neuropathies of the upper extremity can cause hypoechoic swelling and nerve compression as seen at ultrasound. The ulnar nerve can be compressed at the cubital tunnel of the elbow and Guyon's canal at the wrist. The deep branch of the radial nerve can be compressed at the supinator muscle at the elbow, and the superficial radial nerve may be compressed at the dorsal wrist (Wartenberg's syndrome). In addition to compression at the carpal tunnel, the median nerve may be compressed at the elbow, related to a supracondylar process or by the pronator teres. Knowledge of these key anatomical sites of potential nerve compression is essential for accurate diagnosis of entrapment neuropathies.


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Jon A JacobsonM.D. 

Division of Musculoskeletal Radiology, Department of Radiology, University of Michigan

1500 East Medical Center Dr., TC-2910 L, Ann Arbor, MI 48109-0326