Sacroiliac (SI) Joint Dysfunction

Understanding Sacroiliac (SI) Joint Dysfunction

Also known as: SI Joint Pain, SIJ Dysfunction, Sacroiliitis (inflammatory subtype) The sacroiliac joints — the two large joints where the sacrum (base of the spine) meets the pelvis — are among the most underappreciated sources of low back and pelvic pain. Each joint transmits enormous load between the trunk and legs, has limited motion (a few degrees at most), and is stabilized by some of the strongest ligaments in the body. When one side moves too much, too little, or becomes inflamed, it produces a localized pelvic pain pattern that is often mistaken for lumbar disc disease or hip pathology. Research estimates the SI joint accounts for up to 25% of chronic low back pain — a number that's surprisingly high given how infrequently it's diagnosed in primary care settings.

The classic location is a single spot just below and inside the dimple of the pelvis, over the posterior superior iliac spine (PSIS). Patients often point to it precisely — which is itself a useful diagnostic clue. Pain worsens with transitional movements: rolling in bed, getting out of a car, climbing stairs, standing on one leg. Referred pain into the buttock, groin, or upper thigh is common.

Long drives, pregnancy-related loading, and asymmetric activities like running on a cambered road reliably aggravate the joint. Pregnancy-related ligamentous laxity, leg length discrepancy, prior lumbar fusion (which transfers load to the SI joint above), falls onto the buttock, and repetitive single-leg loading are the leading causes. Hip and lumbar dysfunction above and below can load the SI joint asymmetrically. Core and gluteal weakness removes the dynamic support the joint depends on.

Specific SI adjustments — side-posture diversified, Gonstead, drop-table, or pelvic blocking — restore proper joint motion. We address soft-tissue contributors with glute medius, piriformis, and quadratus lumborum release using ART and myofascial work. Rehabilitation focuses on glute activation (clamshells, bridges, single-leg work), core stabilization, and hip mobility. A supportive SI belt can help during pregnancy or acute flares.

Class IV laser helps inflammation settle. Most SI cases improve significantly within four to eight visits. We screen for inflammatory sacroiliitis — a condition like ankylosing spondylitis that produces similar symptoms but requires rheumatologic management — and refer when the clinical picture suggests it. We may recommend: diversified adjustments, Gonstead, myofascial release, ART, corrective exercise, Class IV laser, posture program Seek immediate care if: You develop progressive neurological symptoms, fever with back pain, severe pain following significant trauma, or bowel/bladder changes — these require urgent medical evaluation.