Piriformis Injection

A straightforward Guide for Patients

What is a Piriformis Injection?

The piriformis muscle is a small but important muscle located deep in the buttocks. It helps rotate the hip and stabilize the pelvis. When this muscle becomes tight, inflamed, or irritated, it can compress the nearby sciatic nerve, leading to buttock pain that may radiate into the leg. This is known as piriformis syndrome.

A piriformis injection is used to reduce inflammation, relax the muscle, and confirm whether the piriformis muscle is the true source of your pain.

Goal of the Procedure

The purpose of a piriformis injection is to:

  • Reduce inflammation within or around the piriformis muscle
  • Relax the muscle to relieve pressure on the sciatic nerve
  • Provide pain relief to help you move more comfortably
  • Improve your ability to participate in physical therapy
  • Serve as a diagnostic tool to confirm the piriformis muscle as the pain generator

Procedure Overview

  • You will be brought into a sterile procedure room and positioned lying on your stomach.
  • The skin over the buttock area is cleansed with an antiseptic solution.
  • Using ultrasound or X-ray guidance, the provider identifies the piriformis muscle and safely directs a small needle into the target area.
  • A mixture of local anesthetic and steroid is slowly injected.
  • The local anesthetic offers immediate but temporary relief, while the steroid works gradually over the next several days to decrease inflammation.
  • The entire procedure typically takes 10–15 minutes, and you may go home shortly afterward.

After the Procedure

Please follow the instructions provided by your care team:

  • You may feel temporary numbness or weakness in the buttock or leg due to the anesthetic — this is normal and expected.
  • Gradually return to normal activities as tolerated.
  • Avoid heavy exercise the day of the injection; walking is encouraged.
  • Some soreness at the injection site can last 1–3 days.
  • Apply ice packs to reduce discomfort if needed.
  • You will receive a follow-up phone call to check your progress.

Expected Results

  • Pain relief may occur immediately due to the local anesthetic.
  • The steroid component typically begins working within 3–7 days.
  • Many patients experience easier movement, better tolerance of therapy, and improved daily function.
  • Pain relief may last weeks to months, depending on the underlying cause.

If Sedation Is Used

(Some patients do not require sedation.)

  • No solid foods for 8 hours before the procedure.
  • Clear liquids (water, clear juice without pulp, tea, coffee without cream) are allowed up to 2 hours before.
  • No carbonated drinks, candy, gum, mints, or throat lozenges within 2 hours of the procedure.
  • Certain medications may be taken with a small sip of water, as directed by your nurse.
  • Failure to follow these instructions may result in rescheduling.

Potential Risks

Piriformis injections are considered safe, but possible risks include:

  • Injection-site pain or bruising
  • Temporary leg numbness or weakness
  • Infection (rare)
  • Bleeding
  • Allergic reaction
  • Sciatic nerve irritation (very rare)
  • Incomplete or short-term pain relief

Insurance Requirements

Insurance companies may require:

  • Documentation of conservative treatments such as stretching, physical therapy, medications, or chiropractic care
  • Imaging if symptoms are atypical or if other conditions need to be ruled out
  • Prior treatments such as NSAIDs or muscle relaxants