Spry Juncture, LLC
How to Evolve Gracefully
Iliopsoas
Region
Low Back/Hip
Origin & Insertion
['Origin (Psoas): Transverse processes and bodies of T12–L5', 'Origin (Iliacus): Iliac fossa', 'Insertion: Lesser trochanter of femur']
Synergistic Muscles
['Rectus femoris', 'Sartorius']
Joints
['Hip joint', 'Lumbar spine']
Primary Actions
['Hip flexion', 'Trunk flexion when femur fixed']
Nerve & Spinal Segment
Femoral nerve
Direct branches from L1–L3 ventral rami
Lumbar plexus; L2–L4
Lumbar plexus; L1–L3
Interesting
Only muscle that connects spine to femur. [Clinically Oriented Anatomy]
Reversal of Action
Pull trunk toward thigh in sit-up
Common Dysfunctions
Anterior pelvic tilt, tight hip flexors, impaired gait
Lumbar compression, tight hip flexor syndrome, back instability
How to Stretch
Lunge stretch with posterior pelvic tilt.
Trigger Points
How to Strengthen
Marching, resisted hip flexion.
Concentric Action
Hip flexion (marching)
Applications:
Rehabilitation for hip flexor weakness, anterior pelvic tilt correction
Eccentric Action
Lower leg slowly from flexed position
Isotonic Action
Marches or resisted knee lifts
Related Conditions
['Hip impingement', 'Lumbopelvic dysfunction']
Isometric Action
Hold leg in hip-flexed position (90°)
Exercise Ideas
['Lunge with reach', 'Hanging leg raises', 'Dead bug with hip flexion']