Investigative Magnetic Resonance Imaging

Korean Society of Magnetic Resonance in Medicine (대한자기공명의과학회)
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Accessory Belly of the Piriformis Muscle as a Cause of Piriformis Syndrome: a Case Report with Magnetic Resonance Imaging and Magnetic Resonance Neurography Imaging Findings

  • Kim, Hae-Jung (Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine) ;
  • Lee, So-Yeon (Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine) ;
  • Park, Hee-Jin (Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine) ;
  • Kim, Kun-Woo (Department of Physical & Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine) ;
  • Lee, Young-Tak (Department of Physical & Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine)
  • Received : 2019.02.18
  • Accepted : 2019.05.09
  • Published : 2019.06.30
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Abstract

Piriformis syndrome caused by an accessory belly of the piriformis muscle is very rare. Only a few cases have been reported. Here, we report a case of piriformis syndrome resulting from an extremely rare type of accessory belly of the piriformis muscle originated at the proximal third portion of the main piriformis muscle and attached separately to the greater trochanter inferior to the insertion of the main piriformis muscle. A definitive diagnosis of piriformis syndrome was made based on magnetic resonance imaging and magnetic resonance neurography findings that were consistent with results of nerve conduction study and needle electromyography.

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References

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