AnatoMemory

Muscle

Erector spinae

Iliocostalis, longissimus, spinalis

TrunkMuscular system

High-yield

Three columns lateral→medial: "I Love Spaghetti" (Iliocostalis, Longissimus, Spinalis). Supplied by dorsal rami.

Overview

The large intrinsic back muscle group (iliocostalis, longissimus, spinalis) that extends and laterally bends the vertebral column and controls forward flexion.

Reference facts

Origin
Broad tendon from the sacrum, iliac crest, and lumbar/sacral spinous processes
Insertion
Ribs, and transverse and spinous processes of vertebrae up to the skull
Action
Bilaterally extends the vertebral column and head; unilaterally laterally flexes the trunk
Innervation
Dorsal rami of spinal nerves (segmental)
Blood supply
Posterior intercostal, subcostal, and lumbar arteries

Frequently asked questions

What does the erector spinae do?

The erector spinae bilaterally extends the vertebral column and head; unilaterally laterally flexes the trunk.

What nerve innervates the erector spinae?

The erector spinae is innervated by the dorsal rami of spinal nerves (segmental).

Where does the erector spinae attach?

The erector spinae originates from the broad tendon from the sacrum, iliac crest, and lumbar/sacral spinous processes and inserts on the ribs, and transverse and spinous processes of vertebrae up to the skull.

What is the blood supply of the erector spinae?

The erector spinae is supplied by the posterior intercostal, subcostal, and lumbar arteries.