SI Joint Fusion
What is the Sacroiliac (SI) Joint?
The SI joint, short for sacroiliac joint, is the big synovial joint located in the pelvis near the base of the spine. Synovial joints are the most common type of joint in the body and have a fluid-filled space where the bones of the joint meet to enable fluid (pardon the pun) movement.
There are actually two SI joints, one on each side of the sacrum, the lowest part of your spine above the tailbone. The SI joints connect the sacrum and the pelvic bones (known as ilium, singular or ilea, plural). The SI joints provide stability and balance between the upper body and legs. Normally, they have very strong ligaments and are able to absorb significant bodily shock.
How does SI Joint pain occur?
SI Joint pain can be due to a traumatic event such as a car accident, wear and tear degeneration, or inflammation called sacroiliitis. One may have too much motion (hypermobility) or too little (hypomobility).
The resulting pain may be dull or sharp, and possibly become referred to the low back, groin, buttocks or thighs. Movements may exacerbate pain, and one may experience muscle spasm as a protective mechanism. Those with pain in their SI Joint may have trouble walking or even standing for extended periods of time.
What are the best treatments?
Studies show that up to 25% of chronic lower back pain is caused by the sacroiliac joint, but SI Joint problems can often be overlooked in diagnosis.1 Once a physician identifies the SI joint as the source of the pain, most of the time it can be treated with nonsurgical methods. This may include NSAIDS, physical therapy or intra-articular (within the joint) steroid injections.
Should these treatments fail to significantly reduce the pain, the SI Joint Fusion procedure may become necessary. Inspired Spine’s minimally invasive technique places compression screws across the joint, or titanium rods.2 The implant placement prevents the SI joint from moving, so it won’t cause pain.
Along with the implant placement, bone graft may be included to help the fusion process. The procedure takes about an hour, and is performed through a tiny keyhole incision.
What are the outcomes of an SI fusion?
To date there have been over 20,000 SI fusions performed in the US, and research has been able to follow outcomes for over 5 years. One large study showed that 82% of patients said they were satisfied and would recommend the procedure for SI joint pain relief.