1194
Refers to inflammation of the sacroiliac joints.
Characteristic finding of ankylosing spondylitis, and less commonly in Reiter’s disease, psoriatic spondylitis, and enteropathic arthritis.
May be asymmetric.
Diagnosed by radiological findings of loss of the normal subchondral plate, indistinctness of the subchondral plate, narrowing or apparent widening of the sacroiliac joint space, subchondral sclerosis on both the iliac and sacral side of the sacroiliac joint, subchondral erosions of the sacroiliac joint and fusion of the sacroiliac joint.
The sacroiliac joint is the joint between the sacrum and the ilium of the pelvis, joined together by ligaments.
The sacrum supports the spine and is supported in turn by an ilium on each side.
The SI joint is a strong, weight bearing synovial joint with irregular margins that produce interlocking of the two bones.
The two sacroiliac joints may be variable in anatomy.
The SI joint is held together by multiple ligaments, with many nerve pain fibers contained in these ligaments.
Can be caused by heavy lifting, straining the back or falling.
Can mimic lower back pain or sciatica.
Pain comes from inflammation of the pain structures within the joint itself.
Diagnosed by having a normal neurological exam with an abnormal musculoskeletal exam.
Palpation over the sacroiliac joint reproduces the pain.
The neurological exam is normal.
Almost 50% of cases of cases are bilateral.
Symptoms include pain and stiffness in the lower back.
Typically worse on getting out of bed in the morning.
Walking exacerbates the pain, and the pain can radiate into the hip, lower back or down the back of the leg.
Treatment includes anti-inflammatory agents, physical therapy and injection of the joint with local anesthetic and corticosteroids.
Platelet rich plasma injected directly into the sacroiliac joint may be helpful.