Muscle Library

Iliopsoas: Pain Pattern and Treatment

The iliopsoas runs from the lumbar spine through the pelvis to the inner thigh. It is the primary hip flexor, and it shortens with every hour of sitting. Its referral pattern lands in the low back, which is why a hip muscle appears in a low back library.

Anatomical illustration of the iliopsoas
The iliopsoas.

Attachments and action

Origin: The psoas major arises from the bodies and transverse processes of the lumbar vertebrae; the iliacus arises from the iliac fossa of the pelvis.

Insertion: The two muscles merge and attach together on the lesser trochanter of the femur.

Action: Flexion of the hip with assistance to external rotation. The psoas portion also stabilizes the lumbar spine in upright posture.

Referral pattern of the iliopsoas highlighted on a posterior figure
Referral zones rendered from the documented maps.
Standing figure, front view. Iliopsoas referral pattern in the groin and front of the thigh.
Front view. Referred pain in the groin and the front of the thigh.

Where the pain is felt: Vertically along the lumbar spine, and to the front of the hip and upper thigh. The signature presentation: low back pain that eases lying with the knees bent. The vertical, one-sided distribution along the spine distinguishes it from patterns that run across the back.

Common causes: Prolonged sitting at a desk or wheel, sit-up-heavy training, sleeping curled, sprinting after a period of inactivity.

Patients say: Trouble standing fully upright after sitting. “My back is tight until I get moving.” A pinch at the front of the hip on stairs.

When to get evaluated: Groin pain with clicking, locking, or giving way points to the joint or labrum, not muscle. Assessment first.

How this muscle is examined and treated

Examination assesses hip extension range and locates the tender fibers through the abdominal wall and at the hip. Needling approach and depth are selected for the anatomy in this region. Acupuncture addresses the nervous system’s hold on the shortened pattern. Assessment and treatment happen in the same visit.

Related conditions

Low Back PainHip & Glute Pain

Explore the full Pain Finder

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

Not relief.
Resolution.

Out-of-Network Insurance Accepted: Anthem BCBS · Oxford · United Health Care · Cigna · Aetna · Self-Pay Available