Author: Dr Peter de Souza
Last modified: 7 November 2022

The psoas major muscle is one of three muscles which originate from the lumbar vertebral column. The other two muscles are the psoas minor and the iliacus.

The psoas major and iliacus join together to insert on the femur and are often considered as a functional unit known collectively as the 'iliopsoas'.

Origin

  • Transerve processes of L1-5
  • Vertebral bodies and discs of T12- L5

Insertion

  •  Lesser trochanter of femur

Action

  •  Main flexor of hip

Innervation

  • Direct fibres of L1-L3 of lumbar plexus

Blood Supply

  •  Lumbar branch of iliolumbar artery