For Chronic Low Back and Buttock Pain

A sacroiliac joint injection is an outpatient procedure for diagnosing and treating lower back and buttock pain.


What are sacroiliac joints?

Sacroiliac joints connect your spine to your hip bone. They connect the bottom of the spine, called the sacrum, to the outer part of the hip bone, called the ilium. You have two sacroiliac joints. One is found on each side of the sacrum. Sacroiliac joints help control your hip area when you move. They help transfer forces from you lower body to your upper body. Each sacroiliac joint has several ligaments to help strengthen it.

What is sacroiliac joint pain?

You may feel pain if a sacroiliac is injured. Sometimes it feels like muscle tension. Other times it can be severe pain. The cartilage inside the joint may be injured. Other times only connecting ligaments surrounding the joint are injured.
You usually feel sacroiliac joint pain in an area from your low back down to your buttocks. But sometimes, if a joint is very inflamed, pain may even extend down the back of the leg.

How do I know if I have sacroiliac joint pain?

If you have pain in one or more of these areas, and it lasts longer than two months, you may have sacroiliac joint pain. Common tests such as x-rays or MRIs may not always show if a facet or sacro-iliac joint is causing pain.

What is a sacroiliac joint injection?

In a sacroiliac joint injection, a local anesthetic (numbing medicine) is injected in one or both of the sacroiliac joints or the ligaments surrounding the joints. The local anesthetic, a numbing medicine, lessens your pain temporarily.

What happens during an injection?

A local anesthetic will be used to numb your skin. The doctor will then insert a thin needle directly into the sacroiliac joint. Fluoroscopy, a type of x-ray, may be used to ensure the safe and proper position of the needle. A dye may also be injected to make sure the needle is at the correct spot.

Once the doctor is sure the needle is correctly placed, the medicine will be injected.