Serratus posterior superior muscle explained

Serratus posterior superior muscle
Latin:	musculus serratus posterior superior
Origin:	Nuchal ligament (or ligamentum nuchae) and the spinous processes of the vertebrae C7 through T3
Insertion:	The upper borders of the 2nd through 5th ribs
Action:	Elevates ribs 2-5 ^[1]
Blood:	Intercostal arteries
Nerve:	2nd through 5th intercostal nerves

The serratus posterior superior muscle is a thin, quadrilateral muscle. It is situated at the upper back part of the thorax, deep to the rhomboid muscles.

Structure

The serratus posterior superior muscle arises by an aponeurosis from the lower part of the nuchal ligament, from the spinous processes of C7, T1, T2, and sometimes T3, and from the supraspinal ligament. It is inserted, by four fleshy digitations into the upper borders of the second, third, fourth, and fifth ribs past the angle of the rib.

Function

The serratus posterior superior muscle elevates the second to fifth ribs. This aids deep respiration.

See also

• Serratus anterior muscle
• Serratus posterior inferior muscle

References

• Clinically Oriented Anatomy, 4th ed. Keith L. Moore and Arthur F. Dalley.
• Board Review Series: Gross Anatomy, 4th ed. Kyung Won Chung.

External links

• - "Intermediate layer of the extrinsic muscles of the back, deep muscles."

Notes and References

1. According to Moore et al (Moore Clinically Oriented Anatomy 7th Edition Chapter 1: Thorax, page 86) and Vilensky et al (Clin Anat. 2001 Jul;14(4):237-41. Serratus posterior muscles: anatomy, clinical relevance, and function. Vilensky JA, Baltes M, Weikel L, Fortin JD, Fourie LJ : The serratus posterior superior and inferior muscles are generally considered clinically insignificant muscles that, based on attachments, probably function in respiration. However, there is no evidence supporting a respiratory role for these muscles. In fact, some electromyographic data refute a respiratory function for these muscles. We suggest that the serratus posterior muscles function primarily in proprioception. Further, these muscles, especially the superior, have been implicated in myofascial pain syndromes and therefore may have greater clinical relevance than commonly attributed to them.