By: Kaitlyn Parrotte, PT, DPT, OCS, CFMT
What is the sacroiliac joint?
You’ve probably heard of SI pain, but what is the SIJ and what can we do if something goes wrong?
The sacroiliac joint (SIJ) connects the sacrum, the wedge-shaped bone at the bottom of the spine, to the ilium, which is one of three bones that make up each half of the pelvis. (1) The sacroiliac joint is designated as a diarthrodial joint, which means it is a moveable joint that is surrounded by connective tissue. (2,3) Each joint is supported mainly by ligaments that lie in front and behind it, that are made up of strong, threadlike types of connective tissue. Stability is also enhanced through ligaments that connect between the spine and the sacrum (sacrospinous ligament), and the sit bone and the sacrum (sacrotuberous ligament). (2)
The SIJ helps us to walk and change positions by being stable enough to move weight from the spine to the legs, while allowing for a small amount of movement between the spine and the pelvis. This small amount of movement between the spine and the pelvis is also important as it allows for the pelvis to expand to make childbirth easier. (2,4) These functions can occur due to the unique design of the SIJ.
According to a well-known researcher named Andry Vleeming, the SIJ gains its stability in one of two ways: through form closure or force closure. Form closure refers to the stability provided by the bony surfaces of the sacrum and ilium, which fit together like a puzzle. You may use this type of stability, for instance, when you are lifting a heavy box, or pushing a very full cart of groceries; you want your SIJ to be as immobile as possible so your trunk can be stiff and rigid, allowing you to move a heavy load without overstressing any muscles in your back. Force closure describes stability occurring through the ligaments and muscles around the joint; this allows for more movement to occur. For this type of stability, think salsa dancing. In salsa dancing you need a great deal of hip and pelvic movement; however, you need those movements to be in control so you can move with precision along with the quick beat of the music. (5-7)
What is sacroiliac joint dysfunction?
Sacroiliac joint dysfunction (SIJD) is a common cause of low back pain, accounting for up to 40% of cases of nonspecific low back pain. (4,8) It can occur in any population: males and females; those with a sedentary lifestyle and those who are athletes. However, there seems to be a slightly greater occurrence in women, with the theory being that since the joint surface in women is smaller and less curved, the SIJ may become dislodged more easily. (2,4) SIJD can have a negative impact on quality of life, from being less active to having a financial impact. For instance, indirect health-care costs associated with low back pain range from $7-$28 billion per year, and individuals lose an estimated 5.2 hours of work time per week. (4)
The origin of SIJ pain is unknown; however, factors that may contribute include fractures, ligamentous injuries, or inflammation that occur with excessive stress to the SIJ. (8) Risk factors for developing SIJD include abnormal walking patterns, differences in leg length, scoliosis (abnormal curvature of the spine), heavy physical exertion, trauma, pregnancy, and back surgery. (8) Presentation of symptoms can vary quite a bit; however, individuals with SIJD often present with achy low back pain that can make it difficult to find a comfortable position. Pain may worsen with running, climbing stairs, or standing from a seated position. Also, if pain is truly coming from the SIJ, a person will not experience symptoms down into the leg, as is seen with sciatic nerve involvement. (4)
How is SIJD diagnosed?
SIJD can be very challenging to diagnose due to the complexity of the joint itself, as well as the variation in pain patterns that can be seen; thus, if you visit a healthcare provider, you may find he or she performs an array of components in an examination. Many individuals have tenderness with touch over the joint; this can help a healthcare provider rule in SIJD. (2,8). Also, various orthopedic tests can be performed that put stress on this joint, such as by putting a person’s trunk or leg in a certain position to see if it recreates symptoms. (2) Imaging can be performed in this area, but it rarely provides clear information that can help make a diagnosis; however, a doctor might recommend it if there is a concern for infection, inflammation, fracture, or other more serious conditions. (2) Injections into the SIJ itself can also be used to help diagnosis this condition, and are shown to be one of the single-most definitive diagnostic tools available. (2) Overall, effective diagnosis for dysfunction at the SIJ requires the use of multiple tools to help increase the accuracy of the condition being ruled in or out.
How can this impact function? Why does it matter?
It is hypothesized that SIJD can have such a significant impact on quality of life because it results in inadequate stability at the joint during movement. If the SIJ is unable to maintain an optimal level of stability, then excessive stresses will likely be placed on surrounding structures and tissues when each leg has body weight going through it. This can lead to other areas of pain, and potentially start the process of degeneration. (4) A recent research group looked at the impact of SIJD on a simple, but common functional task of rising from a chair. They found that in individuals with SIJD, there were significant differences in the amount of weight a person was putting through the leg on the painful side, as well as in the amount of bend at the hips when sitting. They also found that when individuals began to rise from a chair, muscles on the side of SIJ did not turn on right away, which means the muscles were not helping to keep the SIJ from moving too much. (4) Thus, this condition can make it challenging to use the body efficiently due to pain and weakness, which can negatively impact function throughout a given day.
What can physical therapy do?
Once a person is diagnosed with SIJD, what can be done? Research has shown that non-surgical treatment, such as physical therapy, can be very beneficial for someone with SIJD. If you see a physical therapist, you will likely receive some variation of joint mobilization and exercise, which is shown to help achieve significant improvements in pain, function, alignment, and muscle control. Exercise programs that emphasized pelvic stability through core, pelvic floor, and gluteus (hip and buttock) exercises, as well as increasing the strength of hip rotator muscles, decreased pain and decreased reported disability after a range of 8-12 weeks. (8,9) In other studies, an exercise program that focused mostly on gluteus maximus strengthening was utilized, since this muscle is considered one of the primary stabilizers of the SIJ. The exercises in these programs included bridging, single leg bridging, hip extension on hands and knees, fire hydrants, deadlifts, and single-leg squatting. In these studies, participants reported less pain after the course of treatment, demonstrated increased muscle strength, and returned to normal daily activities. (10,11) While there is no set exercise protocol established at this point, a strengthening program, with or without a home program, is a mainstay for treating this condition, and results in improved function.
Are there other treatments?
In some cases, physical therapy alone is unable to resolve the issue. In these situations, a patient may be given an injection of corticosteroids to decrease inflammation, in or around the SIJ. Prolotherapy is also sometimes used in this population to help reconstruct or regenerate damaged or weakened connective tissue. While it is helpful to know what other options are out there, it is important to note that the research in these areas is continuing to develop, and there is no consensus on dosage or who is the optimal candidate. (2)
The sacroiliac joint is a complex joint between the back and the pelvis, that allows for minimal mobility, and is required to maintain stability between the trunk and the legs. It can become painful due to direct or indirect trauma, which can have a significant impact on function and quality of life. While diagnosis can be tricky due to the wide variety of symptoms, research is finding that conservative care through physical therapy can make a significant difference by promoting optimal alignment and stability. If you or someone you know is struggling with sacroiliac joint dysfunction, make an appointment with a physical therapist today to help improve function. Feel free to contact our office at 212-354-2622, or visit our website (www.beyondbasicsphysicaltherapy.com) for more information!
1. Ullrich, Peter F. “Sacroiliac Joint Anatomy.” Spine-Health, www.spine-health.com/conditions/spine-anatomy/sacroiliac-joint-anatomy.
2. Peebles R, Jonas CE. Sacroiliac joint dysfunction in the athlete: diagnosis and management. Current Sports Medicine Reports, vol. 16, no. 5, 2017, pp. 336-342.
3. “Diarthrodial Joint.” Biology Online, www.biology-online.org/dictionary/Diarthrodial_ joint.
4. Capobianco RA, Feeney DF, Jeffers JR, et al. Sacroiliac joint dysfunction patients exhibit altered movement strategies when performing a sit-to-stand task. The Spine Journal, 2018, DOI: https://doiorg/10.1016/j.spinee.2018.03.008.
5. Vleeming A, Stoeckart R, Volkers AC, et al. Relation between form and function in the sacroiliac joint. Part I: Clinical anatomical aspects. Spine, vol 15, 1990, pp. 130-132.
6. Vleeming A, Volkers AC, Snijders CJ, et al. Relation between form and function in the sacroiliac jt. Part II: Biomechanical aspects. Spine, vol 15, 1990, pp. 133-136.
7. Vleeming A, Schuenke MD, Masi AT, et al. The sacroiliac joint: an overview of its anatomy, function, and potential clinical implications. J Anat, vol 221, 2012, pp. 537-567.
8. Al-Subahi M, Alayat M, Alshehri MA, et al. The effectiveness of physiotherapy interventions for the sacroiliac joint dysfunction: a systematic review. J Phys Ther Sci, vol 29, 2017, pp. 1689-1694.
9. Albright J, Allman R, Bonfiglio RP, et al. Philadelphia Panel Evidence-Based Clinical Practice Guidelines on Selected Rehabilitation Interventions for Low Back Pain, Physical Therapy, vol 81, n 10, 2001, pp. 1641–1674.
10. Added MAN, de Freitas DG, Kasawara KT, et al. Strengthening the gluteus maximus in subjects with sacroiliac dysfunction. International Journal of Sports Phys Ther, vol 13, n 1, 2018, pp. 114-120.
11. Yoo WG. Effect of the single-leg, lateral oblique, decline squat exercise on sacroiliac joint pain with knee pain. J Phys Ther Sci, vol 28, 2016, pp. 2688-2689.