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Iliopsoas

Contents

Anatomy

Iliacus

Position

  • Deep

Origin

  • Upper 2/3 of fossa iliaca
  • Spina iliaca anterior superior (SIAS)
  • Sacral ala

Insertion

  • Trochanter minor femoris

Main function

  • Hip
    • Flexion
    • Lateral rotation
  • Pelvis
    • Anterior tilt

Secondary function

  • Pelvis
    • Contralateral rotation

Nerve innervation

  • Segmental
    • L1-L4
  • Peripheral
    • Nervus femoralis

Arterial supply

  • Iliolumbar artery
  • Obturator artery

Psoas major

Position

  • Deep

Origin

  • Along the lateral side of the lumbar vertebrae bodies and intervertebrae discs of Th12-L5
  • Anteriorly on processus transversi L1-L5

Insertion

  • Trochanter minor femoris

Main function

  • Hip
    • Flexion
    • Lateral rotation
  • Trunk
    • Flexion
    • Lateral flexion
  • Pelvis
    • Anterior tilt

Secondary function

  • Trunk
    • Contralateral rotation
  • Pelvis
    • Contralateral rotation

Nerve innervation

  • Segmental
    • L1-L4
  • Peripheral
    • Plexus lumbalis

Arterial supply

  • Lumbar artery
  • Iliolumbar artery

Psoas minor

Position

  • Deep

Origin

  • Anterolateral along the medial side of the vertebrae bodies and the intevertebrae discs of Th12-L1

Insertion

  • Fascia iliaca
  • Iliopectinal eminens

Main function

  • Trunk
    • Flexion
  • Pelvis
    • Posterior tilt

Nerve innervation

  • Segmental
    • L1
  • Peripheral
    • L1 spinal nerve

Arterial supply

  • Lumbar artery

Referred pain pattern

Iliopsoas - pain pattern - anterior view

Muscle type

  • Psoas major and minor
    •  Postural
      • Shortens when overactivated
  • Iliacus
    • Unknown

Symptoms

  • Difficulty getting up from seated position
  • Loss of full range of motion in extension for the hip
  • 'Pseudo-appendicitis'
  • Scoliosis
  • Unable to perform a sit-up
  • Antalgic gait
  • Difficulty walking stairs

Muscular attachments

Origin of iliacus and insertion of iliacus and psoas major

Videos

Short version

Detailed version

Variation, short version

Variation, detailed version

MYOFASCIAL LINES

Deep Ventral Line

Synergists

Hip - Flexion

Hip - Lateral rotation

Trunk - Flexion

Trunk - Lateral flexion

Pelvis - Anterior tilt

Antagonists

Hip - Extension

Hip - Medial rotation

Trunk - Extension

  • Erector Spinae
    • Iliocostalis
    • Longissimus
    • Spinalis
  • Transversospinalis
    • Semispinalis
    • Multifidus
    • Rotatores
  • Quadratus Lumborum
  • Trapezius (middle and lower)
  • Interspinales
  • Levatores Costarum

Trunk - Lateral flexion (contralateral side)

Pelvis - Posterior tilt