There are two sacroiliac (SI) joints located at the back of the pelvis. These strong, stable synovial joints are formed between the sacrum and the ilium of the pelvis. The SI joints are covered by two different kinds of cartilage: the sacral surface has thick hyaline cartilage, and the ilial surface has thinner fibrocartilage. The SI joint’s stability is maintained mainly through very strong ligaments both between the joints (interosseous ligament) as well as external support from ligaments such as the sacrospinous and sacrotuberous ligaments.
The sacroiliac joint can become injured as a result of a ligamentous sprain/hypermobility (excessive movement). This is often reported in pregnancy, whereby pelvic instability may occur as a consequence of the hormone relaxin, increasing the flexibility of the ligaments of the pelvis to help enable the mother to carry, and give birth to, her baby.
The sacroiliac joint can also become injured or “locked up” as a consequence of direct trauma stretching or compressing the joint. Furthermore, due to an alteration in pelvic biomechanics and muscular tension, the sacroiliac joint can contribute to pain arising from other complaints such as facet sprains, discal injuries, leg length discrepancies, iliotibial band friction syndrome, trochanteric bursitis, etc.
Common symptoms reported with sacroiliac joint dysfunction are localised pain over the sacroiliac joint with possible referral into the low back or buttock. This pain may be worse with weight bearing, particularly with walking and sitting. It can also be felt with bending.
(The list of conditions given above and subsequent explanations are intended as a general guide and should not be considered a replacement for a full medical examination. Furthermore, we do not purport to treat all the conditions listed. Should you wish to discuss any of these conditions with our chiropractors, please do not hesitate to phone the clinic on 020 7374 2272 or email firstname.lastname@example.org).