Erector Spinae Muscle Group - Anatomy & Physiology

Anatomy

Origin:

• Iliocastalis
  • Lower posterior surface of the sacrum & posterior ribs
    
• Longissimus
  • Transverse processes of lumbar & thoracic vertebrae
    
• Spinalis
  • Transverse processes of thoracic & cervical vertebrae & ligamentum nuchae (posterior neck ligaments)

Insertion:

• Iliocastalis
  • Transverse processes of the cervical vertebrae & posterior ribs
    
• Longissimus
  • Transverse processes of the cervical & throacic vertebrae & the mastoid process of the skull
    
• Spinalis
  • Spinous processes of the thoracic & cervical vertebrae & the occipital bone of the skull

Major Arteries:

• Iliocastalis
  • Intercostal arteries
  • Lumbar arteries
    
• Longissimus
  • Lateral sacral artery
    
• Spinalis
  • Lateral sacral artery

Neural Innervation:

• Iliocastalis
  • Posterior branch of spinal nerve
    
• Longissimus
  • Posterior branch of spinal nerve
    
• Spinalis
  • Posterior branch of spinal nerve

Trigger Points:

Physiology

Concentric Functions:

• Iliocastalis
  •  
  • Lateral flexion of the (thoracic, lumbar & cervical) spine
  • Rotation of the  (thoracic, lumbar & cervical) spine
    
• Longissimus
  • Extension of the (thoracic, lumbar & cervical) spine
  • Lateral flexion of the (cervical) spine
  • Rotation of the (cervical) spine
    
• Spinalis
  • Extension of the (thoracic, lumbar & cervical) spine

Eccentric Functions:

• Decelerates flexion, rotation and lateral flexion of the spine

Isometric Function:

• Dynamically stabilizes the spine during functional movements

Related Muscles:

• Quadratus Lumborum

• Splenius

• Multifidus

Antagonist:

• Rectus Abdominis

Exercises:

• Lower Back Exercises

More Images of the Erector Spinae Muscle

More Information about the Erector Spinae Muscle

The erector spinae muscle group is a bundle of paired bundle of muscles & tendons that run more or less vertically, extending throughout the lumbar, thoracic & cervical regions of the spine.  For classification purposes, each of the erector spinae muscles are divided in sections which the lumborum, thoracis, cervicis & capitis.

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