Erector Spinae

The erector spinae (sometimes known as sacrospinalis) is often described as a group of different muscles called iliocostalis, longissimus and spinalis. Erector spinae consists of lots of small fibres which are situated very close to the spine.

Origin

• Posterior crest of the ilium
  
  
• Lower posterior surface of the sacrum
  
  
• Lower 7 ribs
  
  
• Spinous processes of T9-L5
  
  
• Transverse processes of T1-12

Insertion

• Angles of the ribs
  
  
• Transverse processes of all vertebrae
  
  
• Base of the skull

Actions

• Extension of the spine
  
  
• Lateral flexion (side-bending) of the spine
  
  
• Maintains correct curvature of the spine

Innervation

• Dorsal rami of cervical, thoracic and lumbar spinal nerves

Daily uses

• Maintaining good posture

Example strengthening exercises

• Dorsal raises
  
  
• Side-bends

Example stretches

• Lower back stretch
  
  
• Back arch stretch
  
  
• Back slump stretch

Related injuries

• Lower back pain

Related muscles

• Multifidus