Serratus Posterior Inferior

Description

General

• Serratus Posterior Inferior
• Posterior serratus muscle
• Spinocostal muscle

General

• Muscle of the lower back which originates on the vertebrae and inserts on the ribs
• Helps depress the ribs during expiration

Origin

• Spinous process of vertebrae T11-L2

Insertion

• Ribs 8-12 (inferior borders, near rib angles)

Action

• Depresses ribs (accessory muscle of expiration)

Vascular Supply

• Intercostal Arteries

Innervation

• Spinal nerves T9-T12 (anterior rami)

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Clinical Significance

• Unknown

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See Also

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

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