Sacroiliac Joint Pain Fact Sheet About Lower Back Pain
Up to 85% of all people have lower back pain at some point in life.1 Low back pain is second only to upper respiratory problems as a reason for visits to a physician,2 generating 15 million office visits annually.3 It is the fifth-ranking cause of admission to hospital and the third most common cause of surgical procedures.3,4,5 In 2005, annual direct and indirect costs for treatment of low back pain has reach $86 Billion.6
What is the sacroiliac joint?
The sacroiliac joint forms the lowest segment of the spine and distributes the force delivered from the upper body. Sacroiliac joints are located on either side of the sacrum, which is in the low back and the pelvic areas. The sacroiliac joint connects the sacrum, the triangular bone at the bottom of the spine, with the pelvis iliac crest.
What is the function of the sacroiliac joint? The function of the sacroiliac joint is to transfer weight and forces due to movement from your upper body through the pelvis to your legs and vice versa. The pelvis acts as a central base through which large forces are transferred and dissipated. The primary role of the sacroiliac joint is to provide stability for the pelvis, and to bear the load of the upper body.
Why does the sacroiliac joint start having problems?
Potential causes of sacroiliac joint problems include degenerative disease, history of trauma, pregnancy/ childbirth, and other unknown reasons. The sacroiliac joint may be disrupted due to lack of joint continuity (injury, traumatic event or repetitive trauma to the joint) or may suffer from sacroiliitis (swelling) resulting from a variety of causes.
How does the sacroiliac joint cause pain?
The sacroiliac joint is a synovial joint and has a nerve supply that originates from multiple lumbosacral root levels with partial innervation from L2 (anterior joint) to S3 (posterior joint). Strong ligaments encase each joint and allow for approximately two to four millimeters of movement during weight-bearing and forward flexion. When these ligaments become damaged either due to normal wear and tear or by injury, they may have excessive motion. This excessive motion may inflame and disrupt the joint and surrounding nerves. When this happens, people can feel pain in their back or buttocks, especially with lifting, running or even walking.
How common are sacroiliac joint problems?
It is commonly reported in clinical literature that up to 25% of all low back pain is caused by the sacroiliac joint.7 In addition, the incidence of sacroiliac joint degeneration in post-lumbar fusion patients is 75% at 5 years post-surgery.8
How is low back pain due to the sacroiliac joint manifested?
Many people have low back pain associated with the sacroiliac joint that begins spontaneously. However, in just as many reported cases, sacroiliac joint pathology can be related to a specific event, often an injury. It is difficult to directly relate any specific functioning difficulty (including walking, sitting, standing, sleeping on the affected side, job activity, bowel movements, cough, sneeze, etc.) to the sacroiliac joint as a source of pain. One key indication is the specific location of the pain in the lowest back and buttock region.
Who is at risk for sacroiliac joint problems?
Injury from accidents, including falling, is a predisposing factor for sacroiliac joint pain. Women may be at increased risk for sacroiliac joint problems because of their broader pelvises, the greater curve of their necks, and shorter limb lengths. Pregnancy often leads to stretching of the pelvis, specifically in the sacroiliac ligaments. In addition, clinical literature has also documented the incidence of sacroiliac joint degeneration in post-lumbar fusion surgery is 75% at 5 years post-surgery.8
Is the sacroiliac joint part of a low back pain differential diagnosis?
Most published differential diagnosis for low back pain fail to consider sacroiliac joint as a source of lower back pain.9, 10 Underscoring the need for proper diagnosis is the fact that pain caused by sacroiliac joint dysfunction can mimic discogenic or radicular low back pain potentially leading to the wrong diagnosis and treatment such as lumbar spine surgery.11
1. Frymoyer JW (1988) Back pain and sciatica. N Engl J Med 318:291–300
2. Anderson GBJ. Epidemiologic features of chronic low-back pain. Lancet 1999; 354:581-5.
3. Hart, et al. Physician office visits for low back pain. Frequency, clinical evaluation, and treatment patterns from a U.S. national survey. Spine. 1995;20(1):11-9.
4. Praemer A, Furnes S, Rice DP. Musculoskeletal conditions in the United States. Rosemont: AAUS, 1992: 1–99.
5. Taylor, et al. Low-back pain hospitalization: recent United States trends and regional variations. Spin 1994; 19: 1207–13.
6. Martin, et al. Trends in Health Care Expenditures, Utilization, and Health Status Among US Adults With Spine Problems, 1997-2006 Spine. 2009; 34(19):2077-2084
7. Cohen, Steven P. Sacroiliac Joint Pain: A Comprehensive Review of Anatomy, Diagnosis, and Treatment. Anesth Analg 2005; 101:1440-1453
8. Ha et all. Degeneration of Sacroiliac Joint After Instrumented Lumbar or Lumbosacral Fusion. Spine 2008: 33(a): 1192-1198