Iliocostalis Thoracis: Pain Pattern and Treatment
The iliocostalis thoracis is the outer column of the erector spinae across the mid back, running from the lower ribs to the upper ribs beside the spine. Its documented pattern reaches in two directions: up toward the shoulder blade, and forward around the chest wall or the abdomen on the same side. That forward reach is why this muscle turns up in emergency departments as chest pain or belly pain with normal tests. This is a sub-page of the erector spinae group page.
Attachments and action
Origin: The upper borders of the angles of the lower six ribs.
Insertion: The angles of the upper six ribs and the transverse process of the seventh cervical vertebra.
Action: Extension of the thoracic spine; with one side working, side-bending; it moves with every deep breath through its rib attachments.
Where the pain is felt: Beside the spine in the mid back, spreading up toward the inner edge of the shoulder blade. Around the chest wall on the same side, which can feel like a heart or lung problem. From the lower points, forward into the abdomen on that side.
Common causes: Lifting and twisting; long hours bent forward; a coughing illness; rowing and paddling; a fall or a car accident that jarred the mid back; scoliosis that keeps one side working harder.
Patients say: "Chest pain, and the cardiologist found nothing." "It wraps around from my back to my front." A deep ache beside the shoulder blade that pressing the blade does not reach.
When to get evaluated: Chest pain with pressure, sweating, shortness of breath, or pain on exertion needs cardiac evaluation before anything else. Chest wall pain with a rash along one side needs medical evaluation for shingles. Abdominal pain with fever, vomiting, or tenderness to a light touch needs medical evaluation first.
How this muscle is examined and treated
Examination tests extension and side-bending, presses the outer column of the mid back at the sixth and eleventh rib levels for the point that reproduces the wrap-around pain, and confirms the chest and abdomen findings are the referred kind. Needling here addresses the muscle over the ribs beside the spine, at a shallow angle. Assessment and treatment happen in the same visit.
Related conditions
Chronic Pain PatternsShoulder DysfunctionLow Back Pain
This page is educational. It describes muscle referral patterns commonly associated with pain; it does not diagnose your condition. Individual patterns vary. For evaluation of your specific pain, see a licensed clinician. Seek immediate medical care for emergencies. Eugene Baek, L.Ac. · New Jersey License 25MZ00080600