iliocostalis thoracis (iliocostalis dorsi)

Introduction

Deep back muscle.

Origin

medial side of angles of lower 6 ribs

Insertion

angles of upper 6 ribs

Action

extends, abducts & rotates thoracic vertebrae

Innervation

• dorsal rami of thoracic spinal nerves

More general terms

• erector spinae (musculus sacrospinalis)