Scalenus pleuraris muscle

The scalenus pleuraris muscle (also known as scalenus minimus) is an anatomical variant; a small inconstantly identified ill-defined muscle usually extending from the C7 anterior tubercle to insert into the suprapleural membrane (of Sibson) and the first rib posterior to the groove for the subclavian artery . The presence of a scalenus minimus muscle has been well documented but with poor agreement on exact definition with prevalence ranging from 7.8 to 71.7% of cadaveric studies .

Summary

  • origin: anterior tubercle of the transverse process of C7
  • insertion: suprapleural membrane; inner border of first rib

Related pathology