The sacro-iliac joints are large joints that join the spine to the pelvis. They carry the weight of the body from the spine, through the pelvis to the hips. They can be affected by arthritis and strained by unaccustomed or heavy exercise. They are sometimes a cause of back pain and of pain around the hip and buttock that goes down into the leg.
Injection of the sacro-iliac joints, can help to find out if these joints are contributing to your back pain, and treat the pain. Without other treatment, the pain will sometimes return. It is often necessary to treat more than one joint. Sometimes the injections may need to be repeated. We often arrange for other treatment after the injection to help the joints work in a more normal way.
When the injection is performed, you will need to lie on your stomach for about 20 minutes
A small needle is put into a vein on your hand or forearm so that we can give medicines rapidly should they be needed. An X-ray machine is used to take pictures of the injection. If there is any possibility of pregnancy, then we cannot perform the injection. The site of the injection is cleaned with cold antiseptic. A small injection of local anaesthetic (lidocaine), which stings for a few seconds, is used to numb the skin over the facet joints in the back.
One or two fine needles are placed into the joint, which can be uncomfortable if the joint is tender. The needles are checked by injecting a small amount of iodine-containing dye (iopamidol) that shows up in the X-rays. The treatment is then injected.
Local anaesthetic.(bupivacaine) in the injection will reduce the pain within a few minutes, and will work for several hours. There may be some warmth, a little discomfort, weakness, a feeling of heaviness and sometimes a feeling of numbness that includes the leg and lasts for a few hours at most.
There is a small possibility that sacro-iliac joint injections may cause faintness or a fall in blood pressure. The injection cannot be given to patients who are sensitive or allergic to the drugs used. We put a dressing over the injection, and you should tell us if you are allergic to plasters, tapes or dressings. It is too dangerous to perform the injection on patients with clotting problems, or are taking anticoagulants. It is also too dangerous to perform the injection when there is an infection of the skin of the back, or septicaemia.