The piriformis muscle is involved in rotation of the thighbone. In its course running from the sacrum to the outside of the hip, it can compress the sciatic nerve
What is the piriformis muscle and why does it matter?
The piriformis muscle is involved in rotation of the thighbone. In its course running from the sacrum to the outside of the hip, it can compress the sciatic nerve. This results in pain that runs down the back of the leg into the sole of the foot. This is called piriformis syndrome. In some cases, the relationship to the nerve is more complicated, and imaging may be required to better characterize whether the nerve runs under, through, or even around the piriformis muscle.
What is the treatment for piriformis syndrome?
Piriformis syndrome is initially treated conservatively with physical therapy, heat, and NSAIDs. Stretching exercises are critical to lengthening the piriformis muscle so that it does not continue to compress the sciatic nerve. If conservative measures are ineffective, or if pain is so severe that stretching is too painful, piriformis injections can be performed.
What is a piriformis injection?
During a piriformis injection, the doctor will place a needle into the lateral aspect of the piriformis muscle. After confirming appropriate spread of contrast dye, a small amount of numbing medicine and steroid is placed into the muscle. This can allow for relatively painless stretching and also relief of any inflammation around the nerve itself.