Piriformis Muscle Origin: Pelvic surface of sacrum and sacrotuberous ligament. Insertion: Superior border of greater trochanter of femur. Action: Laterally rotates and transversely abducts thigh at hip joint. Innervation: Nerve to piriformis (S1-S2). #piriformis #piriformissyndrome #piriformismuscle #sciaticapain #backpaintreatment #backpain #osteopathy #osteopatia #osteopathicmedicine #osteopathicmanipulation #physiotherapy #physiotherapist #chiropractic #manualtherapy #sportsmassagetherapist #