The Sacroiliac joints (SIJ) are located at the very bottom of the back, one either side of the spine at the level of the sacrum and connects to part of the hip bone known as the ilium. It makes up the rear part of the pelvic girdle. SIJ dysfunction is a term which is commonly used when talking about sacroiliac injuries. This dysfunction refers to either hypo (low or locked) or hypermobility (high or too mobile).
This can then lead to problems with surrounding structures such as ligaments and muscles, which means SIJ problems can cause a wide range of symptoms throughout the lower back and buttocks, or even the thigh or groin. The function of the SI joints is to allow twisting movements when we move our legs.
Symptoms of Sacroiliac joint pain
- Symptoms of sacroiliac joint pain consist of pain at the bottom of the spine, usually located on one side.
- Sometimes it is described as a band of pain across the lower back.
- The pain can range from a dull ache, to a sharp pain that restricts movement.
- Sacroiliac joint pain may radiate out into your buttocks and low back, groin and occasionally testicles.
- Difficulty turning over in bed, putting on shoes and socks and pain climbing in and out of the car.
- Stiffness in the lower back when getting up after sitting for long periods or getting up from bed in the morning.
- There may be tenderness by pressing on the ligaments which surround the joint.
What causes Sacroiliac joint pain?
Causes of Sacroiliac joint pain can be split into four categories; traumatic, biomechanical, hormonal, and inflammatory joint disease.
- Traumatic injuries to the SIJ are caused when there is a sudden impact which ‘jolts’ the joint. A common example is falling backward and landing on the buttocks. This kind of injury usually causes damage to the ligaments which support the joint.
- Biomechanical – Pain due to biomechanical injuries will usually come on over a period of time and often with increased activity or a change in occupation or The most common biomechanical problems include leg length discrepancy, splaying out of the leg and hip, twisted pelvis and muscle imbalances
- Hormonal changes, most notably during pregnancy can cause sacroiliac pain. The hormones of pregnancy cause the ligaments of the pelvis to become loose or lax. Combining this with an increase in weight puts extra strain on the spine that may lead to mechanical changes causing pain.
- Inflammatory Joint Disease – Spondyloarthropathies are inflammatory conditions which affect the spine. These include Ankylosing Spondylitis which is the most common inflammatory condition to cause SI joint pain.