The Piriformis is the small band like muscle that runs deep into posterior hip area under buttock muscle known as Gluteus Maximus. Sciatic nerve originates from lower spine and runs to the buttock under or sometimes through Piriformis muscle and to the posterior knee and lower leg. When the Piriformis muscle is tight, it compresses the sciatic nerve and hence causes a pain in the buttock area. Piriformis tightness is a very common cause of sciatica. The most common symptom is pain in the buttock area which doesn’t radiate to your leg and gets worse with sitting for long time.
Piriformis stretches -
Lie down on your back and bend both knees. Position the affected leg on the opposite side like crossing your leg with knee pointing outwards and lift the unaffected hip towards you by using your hands around your mid-thigh. Hold for 20 to 30 seconds and repeat 3 times everyday.
Cass SP. Piriformis syndrome: a cause of nondiscogenic sciatica. Curr Sports Med Rep. 2015 Jan;14(1):41-4. doi: 10.1249/JSR.0000000000000110. PMID: 25574881.