Spine · Non-operative care

Sacroiliac (SI) Joint Dysfunction

Most spine pain never needs surgery. OSI evaluates you, orders imaging only when it will actually change the plan, and walks you through the non-operative care that handles the vast majority of spine problems — activity guidance, physical therapy, medications, and targeted injections.

Overview

what it is and why it matters
Labeled diagram of the vertebral column: cervical, thoracic, lumbar, sacral, and coccygeal segments with intervertebral discs.
Spine anatomy. The spinal column has 33 vertebrae grouped into the neck (cervical), upper back (thoracic), lower back (lumbar), sacrum, and tailbone. Soft intervertebral discs sit between each pair of vertebrae as cushions; the spinal cord and its nerve roots run through the hollow canal at the back.
OpenStax Anatomy & Physiology · Public Domain

The sacroiliac (SI) joint connects the sacrum to the ilium on each side of the pelvis. It is a synovial joint with a complex ligamentous envelope that allows very limited motion. SI joint dysfunction — pain arising from the SI joint itself — accounts for 15–25% of chronic low back pain. It can result from altered biomechanics, pregnancy, leg length discrepancy, adjacent segment disease after lumbar fusion, or inflammatory arthritis (ankylosing spondylitis).

Classic presentation is pain in the lower back, buttock, and sometimes the posterior thigh, typically unilateral, that is reproduced by direct palpation 2 cm medial to the PSIS and by provocative tests.

Diagnosis

exam first, imaging second

No single test is diagnostic. A cluster of provocation tests — FABER, FADIR, Gaenslen, posterior shear (thigh thrust), and compression — increases diagnostic specificity. Image-guided SI joint injection (with >75% pain relief) is the gold standard for confirmation. MRI may show bone marrow edema in inflammatory disease.

Treatment Path

how care progresses at OSI
1

Physical therapy

Stabilization exercises, pelvic girdle strengthening, and correction of biomechanical factors.

2

SI joint belt / orthotic

Compressive brace can stabilize hypermobile SI joints.

3

SI joint injection

Fluoroscopy or ultrasound-guided corticosteroid injection provides diagnostic and therapeutic relief.

  1. Prolotherapy / PRP injection

    Regenerative injection into SI joint ligaments for hypermobility-related pain.

If Surgery Is Truly Needed

rare for most patients

Surgery helps only a small minority of spine patients — usually those with a specific structural problem plus a nerve issue that isn’t getting better with a structured non-operative trial. When that step is genuinely warranted, OSI coordinates it the same way we coordinate every other part of your care: imaging, records, and the handoff are handled for you, so no part of the process falls on your shoulders.

Further Reading

authoritative sources

External patient-education references and related OSI pages for additional background:

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