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Updated: Aug 6, 2026
Transaxillary First Rib Resection for Treatment of the Thoracic Outlet Syndrome
Published on: September 13, 2020
Magnetic Resonance Neurography Detection of the Wedge-Sickle Sign Fibromuscular Bands in Neurogenic Thoracic Outlet
Delaram Shakoor1, Ajul Shah2, Ek T Tan1
1Department of Radiology and Imaging, Hospital for Special Surgery, New York, New York.
Case:
A 17-year-old girl presented with chronic right arm numbness, cramping, burning pain, and weakness. Initial nerve studies showed slowing in the median and ulnar nerves, but an outside magnetic resonance imaging was negative. Repeat magnetic resonance neurography (MRN) revealed right C8 nerve root and lower trunk enlargement, compressed by a fibrous band from a small cervical rib. The lower trunk appeared indented in a "sickle" shape-termed the wedge-sickle sign. Surgery confirmed the MRN findings.
Conclusion:
MRN can depict the wedge-sickle sign previously seen only on ultrasound, potentially improving sensitivity of MRN for detecting thin fibromuscular bands in neurogenic thoracic outlet syndrome.
