HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text All Versions of this Article: 2232010857v1 223/2/397    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hayashi, N. Articles by Tajiri, Y. Search for Related Content PubMed PubMed Citation Articles by Hayashi, N. Articles by Tajiri, Y.

Accuracy of Abnormal Paraspinal Muscle Findings on Contrast-enhanced MR Images as Indirect Signs of Unilateral Cervical Root-Avulsion Injury¹

¹ From the Departments of Radiology (N.H., T.M., O.A., S.A., K.O.) and Orthopedics (Y.T.), Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. Received April 30, 2001; revision requested June 7; revision received September 24; accepted October 22. Address correspondence to N.H. (e-mail: naoto-tky@umin.ac.jp).

PURPOSE: To evaluate the accuracy of abnormal magnetic resonance (MR) findings in the paraspinal muscles as indirect signs of nerve-root avulsion injury.

MATERIALS AND METHODS: Forty-three consecutive patients suspected of having unilateral root-avulsion injury underwent MR imaging and were evaluated. Paraspinal muscles were evaluated for abnormal signal intensity on T1- and T2-weighted images, abnormal enhancement on images obtained after contrast material enhancement, and muscle volume loss. MR images were interpreted independently by two observers for interobserver variability. MR findings were compared with findings of root continuity, determined with a combination of surgery and clinical evaluation. Sensitivities, specificities, and values of the findings were calculated.

RESULTS: Sensitivities of MR findings in the paraspinal muscles indicating root-avulsion injury were 88% (36 of 41 patients) for abnormal enhancement, 83% (34 of 41 patients) for high signal intensity on T2-weighted images, 37% (15 of 41 patients) for high signal intensity on T1-weighted images, and 71% (29 of 41 patients) for muscle volume loss. Specificities for all findings were 100% (two of two patients). Of the paraspinal muscles, findings in the multifidus muscle were the most accurate and provided the highest interobserver agreement ( = 0.81).

CONCLUSION: Contrast material–enhanced abnormal MR findings in the paraspinal muscles are accurate in indicating root-avulsion injuries, and abnormal enhancement in the multifidus muscle is the most accurate among paraspinal muscle findings.

© RSNA, 2002

Index terms: Muscles, denervation, 30.492 • Muscles, MR, 30.121411, 30.121415, 30.12143 • Nerves, injuries, 30.492 • Nerves, roots, 30.492

This article has been cited by other articles:

				T. Yoshikawa, N. Hayashi, S. Yamamoto, Y. Tajiri, N. Yoshioka, T. Masumoto, H. Mori, O. Abe, S. Aoki, and K. Ohtomo Brachial Plexus Injury: Clinical Manifestations, Conventional Imaging Findings, and the Latest Imaging Techniques. RadioGraphics, October 1, 2006; 26(suppl_1): S133 - S143. [Abstract] [Full Text] [PDF]

				A J P Goddard and A Gholkar Diagnostic and therapeutic radiology of the spine: an overview Imaging, October 1, 2002; 14(5): 355 - 373. [Abstract] [Full Text] [PDF]