A piriformis injection is an injection of local anesthetic and steroid medication into the piriformis muscle. The injection can be done to alleviate pain and identify the cause of buttock and sciatic pain.
The steroid medication helps to decrease the inflammation and/or swelling of the piriformis muscle and sciatic nerve.
The numbing medication works to temporarily stop the spasms of the piriformis muscle for approximately six hours after the injection. Patients may experience pain for a short period of time before the steroid medication takes effect, however, this does not mean the block did not work.
The piriformis muscle begins inside the pelvis and connects to the sacrum, a triangular-shaped bone that sits between the pelvic bones at the base of the spine.
The piriformis muscle aids in helping turn the foot and leg outward and may have the sciatic nerve run under (and sometimes through) it. Spasms in the piriformis muscle can squeeze and irritate the sciatic nerve, leading to buttock and sciatica pain.
Once patients arrive at the clinic, they will be instructed to change into a hospital gown and complete the necessary medical forms. A nurse will take the patient’s vital signs and start an IV, which will be used to administer relaxing medication to minimize discomfort during the procedure.
It’s important for patients to remain awake during the procedure so that they can tell their physician if they experience any unusual symptoms or discomfort.
Once the procedure is ready to begin, the patient will be transported by cart to a special room and positioned on their stomach on a special X-ray table.
The physician will use an antiseptic to cleanse the treatment area and drape sterile towels over the patient’s back. Under X-ray guidance, the physician will identify the exact location for the piriformis injection and inject the local anesthetic and medication. The skin will then be cleansed and a bandage will be applied to the injection site.
Patients will then be transferred to a recovery room where they will be monitored for 30 to 45 minutes. They will be given specific written discharge instructions and allowed to leave by wheelchair with their ride.
The steroid or anti-inflammatory medication will begin to work 24 to 72 hours after the procedure, though sometimes it can take up to one week for the steroid to take effect.
Patients may experience soreness at the injection site for a day or two after the procedure as a direct result of the needle being inserted into the piriformis muscle.
The effects of the injection can last anywhere from days to months.