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Transaxillary First Rib Resection for Treatment of the Thoracic Outlet Syndrome
Published on: September 13, 2020
An accessory middle scalene muscle causing thoracic outlet syndrome
G Paraskevas1, O Ioannidis, B Papaziogas
1Department of Anatomy, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece. g_paraskevas@yahoo.gr
Folia Morphologica
|November 7, 2007
Summary
A rare accessory middle scalene muscle was found, causing thoracic outlet syndrome by compressing nerves and arteries. This finding highlights accessory muscles, not just the primary scalene, as a cause of this condition.
Area of Science:
- Anatomy
- Surgical Anatomy
- Thoracic Outlet Syndrome
Background:
- Thoracic outlet syndrome (TOS) is often attributed to the anterior scalene muscle.
- Understanding anatomical variations is crucial for diagnosing TOS.
Observation:
- A rare accessory muscular bundle was identified in a male cadaver.
- This bundle connected the middle scalene to the anterior scalene insertion point.
Findings:
- The accessory muscle compressed the brachial plexus and subclavian artery.
- This anomaly demonstrated anterior displacement of the middle scalene muscle.
Implications:
- Accessory muscular bands, not solely the anterior scalene, can cause TOS.
- Highlights the importance of recognizing anatomical variations in TOS diagnosis and treatment.
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