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Iliocostalis thoracis
Description
The iliocostalis thoracis is a defined muscle part of the iliocostalis lumborum muscle.
Muscle parts
Lumbar part or lateral division of lumbar erector spinae; Thoracic part
Latin name
Musculus iliocostalis lumborum
Latin muscle parts
Pars lumbalis or divisio lateralis musculus erectores spinae lumborum; Pars thoracica
Group
Epaxial muscle – Erector spinae – Iliocostalis
Etymology
The English name for this muscle is the muscle between the groin, or flank, and the ribs in the loin region. The word iliocostalis comes from the Latin words ilium meaning “groin, or flank,” and costa meaning “rib.”Lumborum comes from the Latin lumbus for “loin.”
Origin
Base of the rib near the transverse process for ribs 7 to 12.
Insertion
Posterior tubercle of transverse process of cervical vertebra 7 and posterior surface of the angle of ribs 1 to 6.
Action
Extension of the vertebral column; assist with lateral flexion of vertebral column;; postural stabilization of vertebral column.
Nerve supply
Dorsal rami of thoracic and lumbar spinal nerves (T7 to L3)
Blood supply
Dorsal branches of the lumbar arteries from the aorta. Dorsal branches of the lateral sacral artery from the internal iliac artery.