The Sacroiliac joint is located at the bottom and just to the side of the back. The joint can become inflamed and painful, causing either a sharp pain or an ache in the lower back which can spread to the buttocks. The pain can be caused by a trauatic impact, poor biomechanics, inflammatory disease or from hormonal changes, such as pregnancy. Read more on the causes, symptoms, and treatment of this joint pain.
Symptoms of SI joint injury
Sacroiliac joint pain is usually located either to the left or right of the lower back although patients sometimes described it as a band of pain across the lower back. Pain can range from an ache to a sharp pain which can restrict movement. Sacroiliac joint pain may radiate out into your buttocks and low back and will often radiate to the front into the groin and occasionally testicles. Stiffness in the lower back when getting up after sitting for long periods and when getting up from bed in the morning is also common.
Read more on sacroiliac symptoms and diagnosis.
Causes & anatomy
The Sacroiliac joints are located at the very bottom of the back, one either side of the spine and help make up the rear part of the pelvic girdle. They sit between the sacrum bone and the Ilia or hip bones. SIJ dysfunction is a term which is commonly used when talking about sacroiliac injuries. This dysfunction refers to either hypo or hypermobility (low or high respectively). In other words, the joint can become 'locked' or be too mobile. This can then lead to problems with surrounding structures such as ligaments (e.g. Iliolumbar ligament) 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 torsional or twisting movements when we move our legs. The legs act like long levers and without the sacroiliac joints and the pubic symphesis (at the front of the pelvis) which allow these small movements, the pelvis would be at higher risk of a fracture.
The concept of the SIJ causing lower back pain is now pretty well understood. However, due to the complex anatomy and movement patterns at the joints and area in general, evaluation and treatment of sacroiliac dysfunctions is still controversial.
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 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/sport etc. The most common biomechanical problems include leg length discrepancy, over pronation, twisted pelvis and muscle imbalances
Hormonal changes, most notably during pregnancy can cause sacroiliac pain. In preparation for giving birth, the ligaments of the pelvis especially increase in laxity. Combining this with an increase in weight putting extra strain on the spine, may lead to mechanical changes which can result in 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.
Treatment of sacroiliac joint pain
Rest from any activities which cause pain, particularly running. Wearing a sacroiliac support belt which may help take the strain off the joint and provide relief from symptoms. It works by applying compression around the hip and across the joint, protecting it from further injury.
If muscle spasm around the area is suspected use a heat pack to help them relax. Don't heat if acute inflammation of the joint is suspected though as this will make the condition worse. In this case, cold therapy may be more effective. A doctor may prescribe anti-inflammatory medications such as ibuprofen which can help reduce inflammation and relax muscles.
A therapist who specializes in back conditions can do a full assessment and diagnostic tests to discover the cause of the problem ruling out medical diseases such as Ankylosing Spondylitis. Electrotherapy such as ultrasound or interferential may be used to treat soft tissues and if indicated and safe to do, level the pelvis via sacroiliac joint manipulation and mobilization. Sports massage may help relieve any soft tissue tension in the area.
A rehabilitation program to correct any muscle imbalances is important. This is likely to include pilates exercises which may help strengthen the core muscles of the trunk. If the above treatment fails, a Corticosteroid injection into the SIJ may be used. Stretching exercises for the muscles of the hip, particularly the hip abductors (on the outside) and gluteal muscles can help if done gently, however, too much stretching with a hypermobile joint can inflame the joint and increase pain.