For this article, surgeons and physical therapists join together to present a current view on the diagnosis and management of sacroiliac joint (SIJ) pain. Anatomy (including nerve innervation) and biomechanics of the sacroiliac joint are reviewed. Drawings of the bones that make up the joint are provided along with photographs of test procedures and X-rays following surgical fusion.
Fusion of the joint is really a last resort effort and only used when all other approaches have failed. Surgery to fuse the joint is not guaranteed to end the painful symptoms. So, nonoperative (conservative) care is really the order of the day. The authors discuss both nonoperative treatment and surgical management.
Before treatment begins, a careful examination and evaluation are required in order to make the diagnosis. 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 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.
Conservative (nonoperative) care is the first step. The patient will be seeing a physical therapist who will assess pain, posture, alignment, core stability, and biomechanics before setting up a patient-specific treatment program. Failure of the patient to improve after at least six months of nonoperative care is required before fusion surgery is even considered.
There are several different ways to fuse the sacroiliac joint -- none of them are easy or guaranteed to be successful. The surgeon may use pins, screws, or plasma-coated implants along with bone graft to hold the sacrum and pelvic bones together and prevent motion at the sacroiliac joint. After surgery, the patient may be in a cast from the waist down to the toes. In some cases a removable splint is used instead of a full cast. Weight-bearing (standing and walking) are limited for up to eight weeks after surgery. The specific guidelines depend on the surgeon's recommendation.
In summary, sacroiliac joint as a cause of low back pain is a challenge to diagnose and treat but not impossible. We've come a long way in our understanding that the sacroiliac joint can cause painful symptoms and in finding ways to solve the problem. Joint mobilization to correct joint alignment, stabilization exercises, and supportive sacral belts are newer additions to our treatment arsenal that can make a difference.
Patients are also counseled to lose weight, quit using tobacco products, and consider behavior therapy for chronic pain that does not go away even with conservative care. Until better ways are found to surgically correct the problem, fusion is the end-choice for this diagnosis.
Reference: Jonathan N. Sembrano, MD, et al. Diagnosis and Treatment of Sacroiliac Pain. In Current Orthopaedic Practice. July/August 2011. Vol. 22. No. 4. Pp. 344-350.