What is the Piriformis?
Piriformis is a deep external rotator muscle of the hip (hip rotation that turns the toes outwards). It runs from the front of your sacrum and attaches onto the bone you can feel on the outside of your hip (greater trochanter of the femur). It is extremely common for people to develop tightness in the piriformis. This leads to multiple conditions including piriformis syndrome – which imposes pain and hip stiffness.
A more unknown fact is that the piriformis contributes to hip internal rotation as well. When the hip is flexed beyond 90 degrees, the position of the muscle changes – exhibiting an internal rotator force on the femur (leg bone). This detail is integral in the effectiveness of a commonly utilised piriformis stretch.
Impact of a Tight Piriformis
When your piriformis is tight, it can lead to deep spasm and hypomobility of the hip. This is the cause of a deep ache directly in the hip, or in the lower back. Furthermore, piriformis syndrome is when tightness in the muscle leads to a compression of the sciatic nerve (which runs down the back of your leg). This can cause sharp, shooting pain down the back of your legs. This highlights the importance of a piriformis stretch into an exercise routine in order to prevent tightness from developing.
To stretch muscle, we must move muscle into a position opposite to its action. For example, the hamstrings extend the hip and flex the knee, thus to stretch it we must flex the hip and extend the knee. This video explains the different positions that the piriformis lies at changing points of hip flexion. This is integral information because as we move into hip flexion >90 degrees, the piriformis CHANGES ACTION to an internal rotator, thus we must utilise hip external rotation to stretch the muscle effectively.