The sacro iliac joint is an ear shaped in which the 2 articular surfaces slide against each other one on the Ilium or pelvic bone and the other on the Sacrum which is a triangular bone at the base of the spine above the tail bone.
Movement of this joint is very limited, in fact too much movement can be a cause of pain. The sacro iliac joints must loosen and stretch during childbirth which is when they achieve their greatest range of movement. Consequently, sacroiliitis is most commonly seen in women. Men can also suffer sacroiliitis but due to other causes such as trauma, arthritis and ankylosing spondylitis and sports.
Pain from a sacroiliac disorder is felt in the lower back, buttocks and groin and can radiate down one or both legs. Sometimes a thickening of the dorsal ligaments can be felt where the dimples are in your lower back. The pain is aggravated by standing for long periods at a time, running jumping and going up stairs.
It is very important that a diagnosis is done by a professional as the pain from sacroiliitis can easily be confused with many other causes of low back pain some of which are more serious than others and will require X Rays or MRI scans to confirm the diagnosis.
The Doctor may prescribe pain relief and muscle relaxants to control the muscle spasms. Injections of corticosteroid may also be suggested.
Physiotherapists use Interferential Diathermy, Tens and Ultrasound to treat sacroiliitis. Accessory movements and manual mobilisations of the joints with massage to help relieve the muscle spasm. Hip and pelvic exercise regime will help prevent a recurrence.