When I described my symptoms to my sister, she immediately thought that I have a sacroiliac joint problem (based on her own experience with the same problem). How can I find out for sure what's causing this pain? It's located to the left of my spine right about where the dimple is above my buttocks. Is that the sacroiliac there?
A careful examination and evaluation are required in order to make the diagnosis. An orthopedic surgeon, osteopathic physician, physical therapist, or chiropractor can perform this type of examination for you. Usually, the patient's history is a key factor in the diagnosis. Studies show that more than half of all cases of sacroiliac joint pain are linked with some form of trauma (fall, motor vehicle accident, direct blow to the low back/sacroiliac joint area). Other factors that can increase the risk of sacroiliac joint problems include pregnancy (stretching of the pelvic ligaments leads to instability), scoliosis (curvature of the spine), polio, and hip arthritis. A previous spinal fusion and unequal leg lengths are two additional risk factors. There isn't one single test that is 100 per cent reliable in diagnosing the sacroiliac joint as the cause of the pain. But by combining the results of the history along with several other tests, the examiner is able to make what's called a presumptive diagnosis. Here are a few of the diagnostic features:
  • The patient can point to one spot as the area of intense pain. The focal area is below the level of the last lumbar vertebra (L5). The spot you are describing sounds very close to where pain is felt with the sacroiliac joint.
  • The pain can shoot down the leg past the knee mimicking a disc pressing on the spinal nerve root but this is less common with sacroiliac joint pain compared with disc pain. Still -- without additional neurologic testing, the examiner can't say it's a disc problem over a sacroiliac joint problem.
  • To follow that last point up, with a true sacroiliac joint problem, the neurologic exam is negative. Performing reflex and muscle strength tests help distinguish between sacroiliac joint dysfunction and a disc problem.
  • Results of test maneuvers (Patrick's test, thigh thrust, manual distraction/compression of the joint, Gaenslen test) must be considered together as no single test is sensitive or specific enough to make the diagnosis.
  • Blood tests may be done to look for any kind of inflammatory disease or infectious process affecting the sacroiliac joint (e.g., ankylosing spondylitis, psoriatic arthritis). And the most definitive test is pain relief with injection of the joint itself. The surgeon uses fluoroscopy (real-time X-rays) to inject a numbing agent into the joint. Anyone who gets relief of 50 per cent (or more) of the pain is likely to have a true sacroiliac joint problem. Once the presumptive or provisional diagnosis has been made, then treatment begins. It's only after treatment directed at the sacroiliac joint has been successful that the presumed diagnosis can be confirmed.