Muscle
Erector spinae
Long intrinsic back muscle columns supporting upright posture
High-yield
Across the back from lateral to medial, the main columns are iliocostalis, longissimus and spinalis. They help extend the spine and control forward bending, with regional differences in their attachments and size.
Overview
Erector spinae is a group of overlapping muscles beside the spine, rather than one uninterrupted muscle. Its columns link pelvic and vertebral attachments with ribs, higher vertebrae and, in the uppermost parts, the skull.
Reference facts
- Origin
- Shared lower aponeurosis attached to the posterior pelvis and sacrum, with additional vertebral and rib origins in regional parts
- Insertion
- Ribs and vertebral processes at higher levels; some upper portions reach the skull
- Action
- Extends and laterally bends the trunk and neck; helps maintain posture and control flexion
- Innervation
- Segmental branches of posterior, or dorsal, spinal nerve rami
- Blood supply
- Regional branches including deep cervical, posterior intercostal, subcostal and lumbar arteries
Clinical correlation
The fascial plane deep to this muscle group is used in the erector spinae plane block. Its relationship to the transverse processes provides an anatomical landmark, while the spread and effect of the block can vary.
Frequently asked questions
What does the erector spinae do?
Extends and laterally bends the trunk and neck; helps maintain posture and control flexion.
What nerve innervates the erector spinae?
The erector spinae is innervated by the segmental branches of posterior, or dorsal, spinal nerve rami.
Where does the erector spinae attach?
Origin: Shared lower aponeurosis attached to the posterior pelvis and sacrum, with additional vertebral and rib origins in regional parts. Insertion: Ribs and vertebral processes at higher levels; some upper portions reach the skull.
What is the blood supply of the erector spinae?
The erector spinae is supplied by the regional branches including deep cervical, posterior intercostal, subcostal and lumbar arteries.