Medical expert of the article
New publications
The iliopsoas muscle and back pain
Last reviewed: 04.07.2025
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Iliopsoas muscle - m. iliopsoas flexes the hip. Also slightly helps with external rotation of the hip, sometimes helps with hip abduction. Helps with flexion of the lumbar spine if the body is tilted forward.
- Origin: M. Psoas Major: bodies of the XII thoracic and I-IV lumbar vertebrae, Processus costarus of the I-V lumbar vertebrae. M. iliacus: Fossa iliaca, Spina lliaca anterior inferior
- Attachment: Trochanter minor
- Innervation: spinal nerves LI - L4 - rr. musculares of the lumbar plexus
[ Diagnostics
With the patient lying on his back, the musculotendinous junction and the fibers of the iliacus muscle can be examined by applying pressure to the lateral wall of the femoral triangle. Pain from the trigger point in this area is usually reflected to the lower back, the anteromedial surface of the thigh, and the groin. In order not to compress the femoral nerve running along the medial surface of this muscle during palpation, it is necessary to slightly abduct the thigh. To find the trigger point in a second possible location, the inner side of the iliac crest is examined.
The patient should relax the abdominal muscles. The examiner's fingers reach the inner surface of the iliac crest and move, starting from the anterior iliac spine along the crest across the muscle fibers. Pain from the trigger zone of this localization is reflected mainly in the lumbar region and in the sacroiliac region.
Indirect palpation of the lumbar muscle through the abdominal wall is quite effective when performed correctly. The fingertips are placed on the abdominal wall along the lateral edge of the rectus abdominis muscle at approximately the level of the navel. Pressure is applied dorsomedial. In the presence of active trigger zones, little effort is required to elicit a pain response. The pain is reflected mainly to the lower back. Usually, muscle tension can only be felt in patients with a thin anterior abdominal wall. If trigger zones are found in one of the iliopsoas muscles, the contralateral muscle should be examined, as they work together.
Referred pain
It projects as a vertical pattern ipsilaterally along the lumbar spine. It extends downwards to the sacroiliac region. Often, referred pain is localized in the upper part of the anteromedial surface of the thigh on the same side. When palpating the trigger zones of the abdominal part of the iliopsoas muscle, the pain is referred mainly to the back. When palpating the trigger zones at the site of attachment of the muscle to the lesser trochanter, the pain is referred to both the back and the hip.