Every time you take a step, your piriformis muscles help to keep your stride in good form.
The piriformis is a flat, pyramid-shaped muscle in the gluteal region (you have one on each side of the body). Located behind the gluteus maximus, the piriformis attaches to the base of the spine (the sacrum) on one end and to the top of the femur, the trochanter, on the other end (Kenhub 2019; Chang, Jeno & Varacallo 2019).
As one of six short external hip rotators, the piriformis muscle helps stabilize the hip joint and move the thigh (Kenhub 2019; Chang, Jeno & Varacallo 2019).
Read on to walk away with more facts about this multifunctional hip mover:
- The piriformis muscle rotates the femur during hip extension and abducts the femur during hip flexion—the latter being a critical movement in walking, since abduction of the femur shifts body weight to the opposite side and prevents falling (Chang, Jeno & Varacallo 2019).
- Piriformis syndrome is an irritation of the sciatic nerve—due to pressure from the piriformis muscle—causing pain in the buttock and leg (Central Physical Therapy 2015; Ro & Edmonds 2018).
- In roughly 20% of the population, the sciatic nerve runs through the piriformis muscle, rather than below it; the nerve is squeezed anytime the muscle contracts (Chang, Jeno & Varacallo 2019; Central Physical Therapy 2015).
- Other causes of piriformis syndrome include repetitive overuse, postural factors, a difference in leg length, and disproportionate placement of weight on one leg or hip over the other (Central Physical Therapy 2015).
- The piriformis is not always clearly defined, as it can merge with the gluteus medius or gluteus minimus (Chang, Jeno & Varacallo 2019).
- To stretch the piriformis muscle, try “reclining pigeon,” a modified yoga pose. (Teach it to your clients, too.) Lie on your back with both feet flat on the floor, knees bent. Rest your right ankle on your left knee and pull your left thigh toward your chest. Hold the stretch for 5 seconds, gradually working up to 30 seconds with each subsequent stretch; repeat on the other side (Revord 2012).
Central Physical Therapy. 2015. Piriformis syndrome: What to do? Accessed Apr. 22, 2019: centralphysicaltherapy.com/Injuries-Conditions/Lower-Back/Research-Articles/Piriformis-Syndrome-What-To-Do/a~1673/article.html.
Chang, C., Jeno, S.H., & Varacallo, M. 2019. Anatomy, bony pelvis and limb, piriformis muscle. StatPearls. Accessed Apr. 22, 2019: ncbi.nlm.nih.gov/books/NBK519497/#article-27239.s1.
Kenhub. 2019. Piriformis muscle. Accessed Apr. 22, 2019: kenhub.com/en/library/anatomy/piriformis-muscle.
Revord, J.P. 2012. Piriformis muscle stretch and physical therapy. Spine-health. Accessed Apr. 22, 2019: spine-health.com/conditions/sciatica/piriformis-muscle-stretch-and-physical-therapy.
Ro, T.H. & Edmonds, L. 2018. Diagnosis and management of piriformis syndrome: A rare anatomic variant analyzed by magnetic resonance imaging. Journal of Clinical Imaging Science, 8 (6).