﻿In this video, we’ll be taking a look at the sacroiliac joint as source of pain.
What is the sacroiliac joint? The sacroiliac (SI) joint is located in the
pelvis and connects the iliac hip bone (-iliac) to the sacrum (sacro-), which is found at the
base of the spine. It is supported by a strong network of ligaments that provides stability
and limits the movement of the pelvis. The complex dynamics between your body’s weight and your
body’s attempts to counteract that force is found in this core region. This is consistent with the
SI joint’s role in controlling and distributing the forces from the upper body into the legs;
acting as a shock absorber for the spine; and supporting the weight of the upper body.
An SI joint irritation may cause patients to experience low back or buttock pain. The
SI joint is subject to many different types of forces including shearing,...
torsion,... rotation,... and tension. The laxity or looseness of the joint decreases, especially
around age 40 or 50 when the joint can naturally fuse. Pregnant women are most vulnerable to pain
as the hormonal changes cause joint laxity. Both this decrease and increase in joint laxity
are known to increase SI joint irritation. Inflammation of this joint is called Sacroiliitis.
Pain is usually worse after maintaining the same position for any length of time.
Diseases that can cause sacroiliitis are psoriatic arthritis, spondylitis and reactive arthritis.
Most people with sacroiliitis present with low back pain, usually worse on one side than the
other, which often radiates into the buttock or upper leg on the affected side. Sacroiliitis is
often confused with pain from the joints (facets) in the spine. While a physical examination and
some diagnostic injections (lidocaine) around the joint can suggest the source of pain,
the definitive diagnosis remains a challenge. . Chronic SI joint pain, defined by persisting pain
that lasts longer than three months, may be due to the degeneration or irritation
of the free nerve endings associated with the SI joint. A change in gait, trauma, post-operative
fusions of the lower lumbar spine, laxity in the ligaments and muscles around the joint,
obesity, and other inflammatory diseases in the body can also affect the sacroiliac joint.
SI joint problems can be difficult to
diagnose because of the proximity of the SI joint to the spine. With the prevalence of back pain and
spinal injuries, it’s important to distinguish SI joint pain originating from the SI joint
as opposed to the lumbar vertebra. For example, degenerative disc disease in the lumbar vertebrae
may be interpreted at the SI joint when the source is actually higher in the lumbar spine.
The key patterns of referral of pain for patients with SI joint problems include thigh,
and the knee. Around 50% of these patients report pain in the back of their thigh. Although there
is a lack of clearly defined guidelines when it comes to diagnosing SI joint pain, physicians
look for pain patterns and reproduction of the buttock and leg pain by pressing on the joint.
An MRI is the preferred diagnostic test for evaluating this problem.
Conservative treatment for SI joint pain includes physical therapy, at-home exercises, and over the
counter medication. Corticosteroid injections and radiofrequency ablative therapies may be offered
to the patients, but the long term effectiveness of these treatments remains controversial.
In severe cases, a SI joint fusion surgery may been offered, but again, effectiveness of this
option is unpredictable. An important part of the recovery process is patient education,
including good posture, proper lifting technique, stretching, and regular exercise
to strengthen the muscles and ligaments around the joint. Fortunately, sacroiliitis often is a
self limiting, and self curing process. Now, you know more about the sacroiliac joint and
the resulting pain from this joint. Until next time, this is Dr. Shim.