The sacroiliac joint is located where your spine and pelvic bones meet, at the base of the spine. It is the source of many nerve endings, which can become inflamed and result in pain.
Sacroiliac joint pain, also known as SI joint pain or sacroiliac joint dysfunction, occurs when the joint is strained or inflamed as a result of degeneration, injury, or trauma. You are at a greater risk of sacroiliac joint pain if you do work involving heavy lifting or frequent twisting and bending of your spine. It can also be caused by a stress fracture or osteoarthritis.
You usually feel the pain associated with sacroiliac joint problems in your lower back, but it can be located in your thigh and lower leg as well. Stiffness of the back and pain that radiates down one leg is also common.
Injecting the joint with a steroid to reduce inflammation that contributes to pain is one way to manage sacroiliac joint pain. Some patients also benefit from a procedure that heats the nerve tissue in order to prevent pain signal transmission, which is a process known as radiofrequency ablation.