What is piriformis syndrome?
Piriformis syndrome is an uncommon condition which involves the piriformis muscle (one of the deep muscles of the buttock) compressing or otherwise irritating the sciatic nerve as it passes under or through the piriformis muscle. This can occur by the muscle tightening or going into spasm. The piriformis muscle is one of the external rotator muscles, so-called because they allow you to rotate your thigh outwards (externally) at the hip.
Symptoms of piriformis syndrome
The symptoms of piriformis syndrome include pain deep in the buttock, and pain radiating down the back of the thigh.
Running, extensive walking and bushwalking, prolonged sitting and trauma all contribute to piriformis syndrome.
Women are affected more often than men.
It is more common in people whose sciatic nerve passes through the muscle.
Piriformis muscle spasm can occur as a result of pelvic dysfunctions (loss of control of the pelvic bones) and is also seen in patients who have very poor core stability (or poor deep muscle stabilisers of the trunk) - in these cases the piriformis muscle compensates for this lack of strength.
Treatment for piriformis syndrome
Stretching, rest from the offending activity if one has been identified, massage and anti-inflammatory medicines are the initial recommended treatment. Core strengthening exercises prescribed by a physiotherapist and manual therapy to the pelvis may be needed in some cases. With severe persistent pain, corticosteroid injections or surgery are sometimes considered. Recent experience suggests Botox injections may be useful in some cases.