The Piriformis muscle is a pesky deep glute muscle with the capacity to cause many issues, including: sciatica, duck feet, and tailbone pain. Piriformis is the most prominent of the deep external hip rotators (muscles that twist your leg to point your toe outward), and can cause a lot of pain when tight. Check out comedian Sinbad's bit on the Piriformis muscle here!
Piriformis Muscle : The Piriformis muscle in red from a rear view, as depicted in Travell & Simons Myofascial Pain and Disfunction
Piriformis Referred Pain Pattern:
The Piriformis muscle can refer pain in a large area of the hip and buttock regions. This may feel like pain in the low tailbone region, or deep in the glute.
Piriformis Referred Pain Pattern 
Piriformis Pain Symptoms:
The Piriformis can cause a host of problems in the tailbone, buttock, and hip regions. When the Piriformis is tight - Piriformis Syndrome can occur (check this link for a Piriformis Syndrome test). This is when the Piriformis muscle gets so tight that it compresses the sciatic nerve (the nerve that runs from the tailbone all the way down the leg), and can cause pain, numbness, or tingling in the leg and foot.
Other signs of Piriformis trigger points and tightness, described by Travell & Simons, include:
- "Patients may report sharp pain on occasion, but often they describe their symptoms as an ache"  p. 1369.
- "Patients may also report a loss in their hip range of motion or flexibility into internal rotation and adduction"  p. 1369.
- The symptoms are likely aggravated in the seated position  p. 1369.
Tenderness and irritation in the Sciatic Notch around the Piriformis  p. 1369.
Piriformis Muscle Pain Relief:
The best tool to massage the Piriformis for trigger point release is the QL Claw device. QL Claw is great for the Piriformis because it stays on the ground, it digs deep into the glutes/Piriformis like a massage therapist, and it allows various levels of pressure by the user. QL Claw was designed to release the 5 muscles that contribute to the majority of low back, hip, and glute pain - and Piriformis is certainly on that list. Buy your QL Claw to own your Piriformis and the 4 other pain-inducing muscles (Psoas, QL, Iliacus, Glute Medius) today!
Piriformis Release Using the QL Claw Device
 Donnelly, Joseph M. Travell, Simons & Simons Myofascial Pain and Dysfunction: the Trigger Point Manual. 3rd ed., Wolters Kluwer Health, 2019.