Serratus muscles

Serratus Posterior Superior origin and insertion

O: Nuchal ligament; spinous processes of C7-T3

I: Superior ribs 2-4

serratus posterior superior action

elevate ribs during inhalation

serratus posterior superior innervation and blood supply

Innervation: Intercostal nerves T2-T5

Blood supply: posterior intercostal arteries

serratus posterior inferior origin and insertion

O: Spinous processes of T11-L2

I: 8th to 12th ribs

serratus posterior inferior action

depress ribs during exhalation

Serratus posterior inferior innervation and blood supply

Innervation: Ventral rami of spinal nerves T9-T12

Blood supply: posterior intercostal arteries, subcostal artery, upper lumbar artery

serratus anterior origin and insertion

origin: ribs 1-8

insertion: medial border of scapula

serratus anterior action

Scapular protraction and upward rotation

serratus anterior innervation and blood supply

Innervation: long thoracic nerve

Blood supply: lateral thoracic artery