The Mystery Muscle
Piriformis syndrome is a disorder caused by compression or irritation to the sciatic nerve which creates sciatica type symptoms such as pain from the tingling and numbness in the buttock and down the back of the leg. It’s important to have a medical professional rule out true sciatica, which is compression or irritation of the sciatic nerve root typically caused by a herniated disc.
Understanding the Piriformis
You have six deep lateral rotators of the hip. All of the deep 6 lateral rotators aid in lateral rotation of the thigh bone in the hip socket. They all originate from the pelvis and insert into the head of the greater trochanter. The subtle variations in the origin and insertion of each rotator determines the functions of each individual muscle. But the most important function of the lateral rotators as a group is to stabilize the head of the femur in the hip socket and stabilize the sacrum.
One of these six muscles is the piriformis. The piriformis lies close to the hip joint beneath the gluteals. The piriformis gets a lot of attention because the sciatic nerve runs underneath it, or through it for approximately 17% of the population. When the piriformis is hypertonic, or abnormally tense, it can cause compression and pain.
The piriformis can turn-out the femur in the hip socket (laterally rotate). And it can bring the leg away from the midline of the body when the leg is in front of the body (abduction with hip flexion).
The piriformis is strengthened as a stabilizer with exercises like footwork or squats in turnout, parallel, or medial rotation. But strengthening of the piriformis must be done with good pelvic alignment and core engagement to be effective.
Joseph Pilates did many of his exercises in lateral rotation because he trained so many dancers at his New York City studio. But it’s not just ballet dancers that need a strong piriformis. We all do. Piriformis strength is important to everyone in many parts of life. A well functioning piriformis is important for gait, balance, and athletes participating in sports that require sudden change of direction.