Trunk (thorax, abdomen, back)

Serratus Posterior Superior

Musculus serratus posterior superior

Origin

Spinous processes of C7-T3 and the ligamentum nuchae

Insertion

Upper borders of ribs 2 through 5

Function

Elevation of the upper ribs; assists inspiration

Innervation

Intercostal nerves T1-T4

Movement & chain

Helps deep inspiration by elevating the upper ribs, with limited functional contribution during quiet breathing.

Palpation

Lies deep to the rhomboids across ribs II–V; palpated medial to the superior scapula during deep inhalation.

Clinical

Elevates upper ribs during deep inspiration; frequent source of refractory interscapular pain and myofascial trigger points.

Segmental innervation

Intercostal nerves T1-T4.

In clinical practice

Ergonomic patient repositioning (log-roll technique in spinal trauma) and pressure offloading; maintain neutral spinal alignment in bedridden patients.

Region in the model

Trunk (thorax, abdomen, back)