Anatomy study note · Pelvis

Piriformis

A muscle of the posterior pelvic wall that leaves the pelvis through the greater sciatic foramen to reach the femur. It is the key landmark of the gluteal region.

Key points

• Front of the sacrum → greater trochanter.
• Through the greater sciatic foramen.
• Nerve to piriformis (sacral plexus).
• Lateral rotator of the hip; sacral plexus lies on it.
• Striated muscle: myotomes + local mesenchyme.
• Nerve supply indicates origin.
• Skeletal muscle: multinucleated, peripheral nuclei, striated.
• Epimysium → perimysium → endomysium.

The full note in the atlas also covers

Relations · Origin · Insertion · Action · Nerve supply · Histology · Development

Sign in free to see it on the 3D model, read the full note and practise questions on it.

Written from

• Snell’s Clinical Anatomy by Regions, 10th ed., ch. 8, PDF pp. 1020–1021, 1047
• Inderbir Singh’s Human Embryology, ch. 7, PDF pp. 92, 108–109
• BRS Cell Biology & Histology, 7th ed., ch. 8, PDF pp. 135–144

More from the pelvis

• Prostate
• Pubic symphysis
• Rectum
• Sacral plexus
• Sacrococcygeal joint
• Sacroiliac joint
• Sacrotuberous and sacrospinous ligaments
• Sacrum
• Seminal vesicle
• Sigmoid colon
• Urinary bladder
• Uterine artery

Privacy policy · Designed by DATXOC LLC.