Serratus Posterior
Original Editor -
Top Contributors - Khloud Shreif, Kim Jackson and Ahmed M Diab
Description[edit | edit source]
Serratus posterior muscle consists of serratus posterior superior and serratus posterior inferior they are intermediate layer of back muscles
Origin[edit | edit source]
Serratus posterior superior: C7-T3 vertebrae spinous process and nuchal ligament
Serratus posterior inferior: T11-L2 vertebrae spinous process
Insertion[edit | edit source]
It inserts into ribs
Serratus posterior superior: at upper border of 2nd-5th ribs
Serratus posterior inferior: at lower border of 9th-12th ribs
Nerve[edit | edit source]
Serratus posterior superior innervated by ventral rami of T1-T5.
Serratus posterior inferior innervated by ventral rami of T9-T12.
Function[edit | edit source]
Both serratus posterior superior and inferior are accessory muscles for respiration
Serratus posterior superior: elevate the ribs during inspiration(accessory muscle of inspiration) and has a stabilization role for thorax.
Serratus posterior inferior: depress the ribs during expiration(accessory muscle of expiration)
Bilateral action of posterior superior/posterior inferior reduce extension of thoracic vertebrae.
Unilateral action: rotate spine to opposite side.
