Dysfunction in the sacroiliac joint, or SI joint, is thought to cause low back and/or leg pain. The leg pain can be particularly difficult, and may feel similar to sciatica or pain caused by a lumbar disc herniation.

What causes sacroiliac pain?

While it is not clear how the pain is caused, it is thought that an alteration in the normal joint motion may be the culprit that causes sacroiliac pain. This source of pain can be caused by either:

  • Too much movement (hypermobility or instability): The pain is typically felt in the lower back and/or hip and may radiate into groin area.
  • Too little movement (hypomobility or fixation): The pain is typically felt on one side of the low back or buttocks, and can radiate down the leg. The pain usually remains above the knee, but at times pain can extend to the ankle or foot. The pain is similar to sciatica, or pain that radiates down the sciatic nerve and is caused by a radiculopathy.

How long will it last?

Unfortunately, the duration and severity of a single episode cannot be predicted based on the onset, location of pain, or even the initial severity. Excruciating initial pain may resolve within several days, while moderate or mild symptoms may persist for weeks. However, up to 30% of individuals will experience recurrent pain or develop persistent pain in the future.

What treatments should I have

All evidence points to remaining as active as possible and guided by pain in the initial stages. Bed rest is no longer accepted treatment and may be harmful. Over the counter medication such as regular paracetamol and anti-inflammatory medications such as ibuprofen are very effective.  If muscular spasm pain are prominent your general practitioner may advise a short course of diazepam.

Rehabilitation

Thorough rehabilitation requires complete and accurate diagnosis that goes beyond the recognition of clinical symptoms and tissue injury. The SIJ is the main link between the spine, hip, and lower extremities, and treatment needs to address functional biomechanic. Working directly with a physio who is skilled in this area is recommended. One must determine if any motion restricts the pelvis and which planes of movement are restricted; whether the SIJ is compensating for a lower-extremity deficit in range of motion, strength, or coordination; or whether the inflammation is caused by disturbance in gait.

Improper or repetitive sport-specific motions can increase stress on the SIJ or adjacent structures; therefore, a detailed history of sports activities is essential.

Strengthening and stabilization. The ligaments of the SIJ and the lumbar spine mesh with the thoracolumbar fascia. These ligaments and fascia are the primary attachments for the main movers and stabilizers of the spine and lower extremities. Thus, coordinated muscle contraction causes compression of the surfaces of the SIJ. The major muscles and fascia involved include the gluteus maximus and medius, latissimus dorsi, hamstrings, abdominals, back extensors, and the thoracolumbar fascia.

Weakness or inhibition of the hip muscles, especially the hip abductors, should be addressed. Functional exercise programs can create a self-bracing mechanism to stabilize the SIJ against large shear stresses applied to the joints under various loading conditions.