Sacroiliac (SI) joint pain is a sharp, stabbing pain that radiates from the hips and pelvis, down to the thighs and up to the lower back.
SI joint pain is responsible for 15 to 30 percent of cases of chronic lower back pain.
The sacroiliac joint is located where the sacrum and ilium meet. The sacrum is the tailbone and the ilium is one of three bones that make up the hip bones. The SI joints support the weight of the body, act as a shock absorber and reduce pressure on the spine.
Causes of SI Joint Pain
SI joint pain may be caused by:
- Ankylosing spondylitis
- Abnormal walking patterns
Symptoms of SI Joint Pain
Individuals with SI joint pain may experience:
- Pain in the lower back, buttocks, hips, pelvis and groin
- Pain in only one of the SI joints
- Increased pain when getting up from a sitting position
- Stiffness or a burning sensation in the pelvis
- Pain radiating to the thighs and upper legs
- Feeling as if legs are unable to support the body and may buckle
Treating SI Joint Pain
SI joint pain may be diagnosed with a sacral lateral branch block and treated with radiofrequency ablation.
What to Expect During a Sacral Lateral Branch Block Procedure
A sacral lateral branch block involves injecting lidocaine near the sacroiliac joints to block the transmission of pain signals to the brain. If the patient experiences at least 50% pain relief, then the physician can verify that the patient is a candidate for radiofrequency ablation.
The patient lies flat on their stomach and the injection site is cleaned and numbed with an anesthetic. The patient is mildly sedated. Using x-ray guidance, the physician inserts the needle toward the sacral lateral nerve branch and injects the lidocaine. Patients are monitored for 15-30 minutes after the procedure and are able to resume normal activities within 24-48 hours.
What is Radiofrequency Ablation?
Radiofrequency ablation is a procedure that involves using an electric current to heat up a small area of nerve tissue in order to halt the transmission of pain signals. The procedure can offer long lasting pain relief for patients with lumbar facet syndrome.
Risks of Radiofrequency Ablation
The procedure is generally safe. Serious complications, such as infection or bleeding at the incision site, are rare. Temporary side effects may include swelling and bruising at the incision site, and weakness or numbness in the legs.
What to Expect During a Radiofrequency Ablation Procedure
Before the procedure begins, the patient will be given an intravenous medication to help them relax. Once the patient is lying on the x-ray table, the doctor will clean the incision site with an antiseptic. Next, he or she will use a local anesthetic to numb the incision site.
The doctor will use x-ray guidance to insert a thin needle into the area experiencing pain. A microelectrode will then be inserted through the needle and the doctor will ask if the patient feels a tingling sensation. A radiofrequency current will be sent through the electrode to heat the nerve tissue.
After the Procedure
The amount of pain relief experienced will vary depending on the cause of pain and location. Patients may experience pain relief that lasts six to 12 months. Some patients may experience pain relief that lasts years.