Piriformis

The piriformis is one of the muscles referred to as the deep six. Essentially it is under the glute max and connects the sacrum (back of pelvis) to the big bony mass on the outside of the upper femur (thigh bone). When the piriformis is tight it can aggravate the sciatic nerve creating nerve pain in the leg.

The image is a posterior view of the pelvis and leg.

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