The deep rotators
It works with a small team under the glutes, the gemelli, obturators and quadratus femoris, that turn the thigh outward and hold the head of the thigh bone in its socket.
Muscle guide · Hips and glutes
Piriformis
Also called deep hip rotator, deep glute muscle
The piriformis is a flat, pear-shaped muscle deep in the buttock, under the gluteus maximus. It runs from the inside of the sacrum at the base of the spine, through a notch in the pelvis, to the top of the thigh bone.
It is famous for its neighbour: the sciatic nerve usually leaves the pelvis just below it, and in some people part of the nerve runs through or above it.
Where the piriformis is and what it does
- Starts at (origin)
- The inner front surface of the sacrum and the nearby pelvis.Anterior surface of the sacrum, ilium near the greater sciatic notch, sacroiliac joint capsule (sources differ on the exact sacral levels)
- Attaches to (insertion)
- The top of the bony knob on the outside of the hip.Superior border of the greater trochanter, blending with the obturator internus and gemelli tendons
- What it does
- Turns the thigh and foot outward when the hip is straight.Hip external (lateral) rotation
- With the hip bent it moves the thigh out to the side, though one source describes the opposite.Hip abduction in flexion (disputed)
- Nerve supply
- Branches of S1 and S2 (some people L5 to S2, or S2 alone); one StatPearls article gives L5, S1, S2.
How it works in everyday movement
Exercises for the piriformis
No study has measured which exercises load the piriformis most. These use its job of turning the thigh outward and steadying the hip, and they are the hip-strength moves the piriformis syndrome guide builds on.
Stretches for the piriformis
Stretching is part of the usual conservative treatment for piriformis syndrome. Stop if a stretch sends pain or tingling down the leg.
3D demoReclined figure four (eye of the needle, Sucirandhrasana)Beginner · No equipment
3D demoStanding figure four (chair pigeon, Eka Pada Utkatasana)Intermediate · A wall
3D demoPigeon preparation (Eka Pada Rajakapotasana prep)Intermediate · No equipment
3D demoAnkle On The KneeBeginner · Other / check instructionsProblems linked to the piriformis
Piriformis syndrome
Buttock pain that may burn or ache down the back of the leg, sometimes with tingling, thought to come from the piriformis irritating the sciatic nerve. Sitting, stairs and squatting tend to aggravate it. It is diagnosed by ruling other causes out and is estimated at 0.3% to 6% of cases of low back pain or sciatica.
A contested diagnosisMixed evidence
After more than 70 years there is still no accepted test for piriformis syndrome, and it has been called both over- and under-diagnosed. Many clinicians now use the broader term deep gluteal syndrome for sciatic nerve trouble in the buttock that does not come from the spine.
Myths worth dropping
Each grade rates the evidence for the correction.
Routines that train it
Questions people ask
What does the piriformis do?
It turns the thigh outward when the hip is straight, and with the other deep rotators it helps hold the hip joint steady.
Is piriformis syndrome real?
It is contested. There is no accepted test, it is diagnosed by excluding other causes, and most sciatica comes from the spine instead.
How do you stretch the piriformis?
Figure-four and pigeon-style stretches, which bend the hip and turn it, put tension on it. Back off if a stretch causes pain or tingling down the leg.
Where is the piriformis?
Deep in the buttock under the gluteus maximus, running from the inside of the sacrum to the top of the thigh bone, right beside the sciatic nerve.
Muscles it works with
Sources
Anatomy and movement education, not a diagnosis or treatment plan. If you have pain that follows an injury, is severe or getting worse, or comes with numbness, weakness or swelling, get it assessed. Health disclaimer.