What is a sacroiliac joint injection and radiofrequency treatment used for?
A sacroiliac joint injection and radiofrequency treatment is used to treat pain arising from the sacroiliac joint. This may present as pain in the lower back, buttocks, or groin. An injection involves injection a solution of local anaesthetic and steroid into the sacroiliac joint under ultrasound or X-ray guidance.
If the pain relief from a sacroiliac joint injection is inadequate, a trial of of injection of local anaesthetics to the nerves giving sensation to the sacroiliac joint may be attempted to see if this gives good pain relief. If there is relief, then a radiofrequency procedure targeting the nerves of the sacroiliac joint can be performed to allow for a longer duration of pain relief.
How is a sacroiliac joint injection or radiofrequency treatment performed?
This procedure is done as a day surgery procedure using only minimally invasive techniques involving thin needles. After placing you on your tummy and giving you some sedation, the skin at the lower back and buttock is cleaned with an antiseptic solution. After this, an injection of local anaesthetic is given to numb the skin before another needle is placed into the sacroiliac joint under ultrasound or X-ray guidance. A solution of local anaesthetic and steroid is given. If a radiofrequency procedure is performed, the pain specialist will test to ensure that the needle is near the pain fibres and not near the nerves that control important functions. The pain specialist will then ablate the nerve to provide lasting pain relief that can last months to years.
How long can the sacroiliac joint injection or radiofrequency treatment last?
The injection generally lasts an average of 6 months to a year. A radiofrequency ablation procedure usually lasts longer with better quality of pain relief.
What are the possible side effects?
Side effects from a sacroiliac joint injection can include a very small risk of infection, bleeding or nerve damage. There might be temporary weakness and numbness of the legs and difficulty passing urine which will recover after a few hours. Sometimes the pain may worsen for up to 2 weeks before improving. If radiofrequency treatment is performed, there might be a change in sensation over the skin at the buttock which might be unpleasant but will usually improve with time.