psoas major


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Related to psoas major: Iliacus, psoas minor, Quadratus lumborum

psoas major

[sō′əs]
Etymology: Gk, psoa, loin
a long muscle originating from the transverse processes of the lumbar vertebrae and the fibrocartilages and sides of the vertebral bodies of the lower thoracic vertebrae and the lumbar vertebrae. It joins the iliacus to form the iliopsoas deep in the pelvis as it passes under the inguinal ligament and inserts in the lesser trochanter. It acts to flex and rotate the thigh and to flex and laterally bend the spine. Compare psoas minor.
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Psoas major and psoas minor

psoas major

medial thigh muscle
  • origin with iliacus (with which it fuses, forming iliopsoas muscle); passes into thigh posterior to inguinal ligament

  • insertion lesser trochanter

  • nerve supply ventral rami of L2 and L3

  • action iliopsoas is the chief flexor of hip joint; iliopsoas flexes trunk on thigh and medially rotates thigh of a fixed limb; iliopsoas spasm causes lateral rotation of femur and foot/leg abduction with fractured neck of femur

References in periodicals archive ?
Of the three muscles (iliacus, psoas major and psoas minor) that make up the iliopsoas, the iliacus provides the major force for anterior propulsion (1).
It also has an intimate connection with the medial and lateral arcuate ligaments which lie around the top of the psoas minor and psoas major respectively.
Psoas major in particular, has intimate anatomical attachments to the diaphragm and the pelvic floor.
The kidneys lay each side of psoas major and psoas minor.
The ilio-iguinal nerve emerges laterally from the psoas major muscle and then passes anterior to the posterior abdominal wall, running around the trunk and inferiorly through the inguinal canal.
05) for cooking loss and shear force of the Psoas major and Quadriceps femoris muscles, moisture, fat, and protein in the lean trim of the forequarter and moisture, fat, ash, and protein in the lean trim of the hindquarter.
Presented in Table 2 are the least squares means and standard errors for cooking loss and shear force of the Psoas major and Quadriceps femoris muscles by beef growth type in pasture and feedlot developed steers.
Least squares means and standard errors for cooking loss and shear force of the Psoas major and Quadriceps femoris muscles by beef growth types in pasture- and feedlot-developed steers Growth type (1) Trait Muscle type LL n = 79 Cooking loss (%) Psoas major 26.