Erector Spinae Muscles

Description

The erector spinae muscles

Deep spinal muscles including semispinalis, multifidus, spinalis, longissimus, iliocostalis

General

• Three groups of deep muscles located on each side of the vertebral column
• Comprise the intermediate layer of the deep (intrinsic) muscles of the back

Iliocostalis

• Origin: Sacrum, Iliac Crest, spinous processes of lower lumbar, thoracic Vertebrae
• Insertion: Ribs

Longissimus

• Origin: Transverse Process
• Insertion: Transverse Process

Spinalis

• Origin:
  • Thoracis: Spinous process of upper lumbar and lower thoracic Vertebrae
  • Cervicis: Nuchal Ligament, spinous process of C7 Vertebrae
• Insertion
  • Thoracis: Spinous process of upper thoracic Vertebrae
  • Cervicis: Spinous process of cervical Vertebrae except atlas

Actions

• Unilaterally: laterally flex the head, neck and vertebral column to the same side
• Bilaterally: Extend the vertebral column.

Vascular Supply

• Lateral sacral artery
• Intercostal and lumbar arteries

Innervation

• Posterior branch of spinal nerve

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Clinical Significance

• Lumbar Strain

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See Also

• Back Anatomy Main
• Back Pain Main
• Physical Exam Back

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