Ask a patient with sacroiliac joint pain to point at it and they will usually place one finger just below the belt line, off to one side. Ask them what they have been treated for and they will usually say sciatica. At Remix Medical in Houston, our pain management physicians use image-guided diagnostic injection to establish whether the SI joint is the actual source before committing to a treatment plan.
What is SI Joint Dysfunction?
The sacroiliac joints connect the sacrum, at the base of the spine, to the iliac bones of the pelvis. They move very little — a few millimeters — but they transfer the entire load of the upper body into the legs.
When a sacroiliac joint becomes inflamed, or when it moves too much or too little, it generates pain in the low back, buttock, groin, and sometimes down the back of the thigh. Because that pattern overlaps heavily with lumbar disc pain, the joint is frequently overlooked.
SI joint dysfunction accounts for a meaningful share of chronic low back pain, and a larger share among patients who have already had lumbar fusion.
Common Causes of SI Joint Dysfunction
1. Prior Lumbar Fusion
Fusing segments of the lumbar spine transfers load to the joints immediately below. The SI joint absorbs it.
2. Pregnancy and Childbirth
Hormonal ligament laxity, weight gain, and altered gait all stress the joint. Symptoms can persist well after delivery.
3. Trauma
A fall onto the buttock, a motor vehicle collision, or a hard landing can injure the joint and its supporting ligaments.
4. Leg Length Discrepancy and Gait Asymmetry
Asymmetric loading over years wears one joint disproportionately.
5. Inflammatory Arthritis
Ankylosing spondylitis and related conditions inflame the SI joints directly, often in younger patients with morning stiffness.
Symptoms of SI Joint Dysfunction
- Pain below the belt line, usually on one side
- Pain in the buttock, and sometimes the groin
- Referred pain down the back of the thigh, typically stopping above the knee
- Worse with standing from a seated position, stair climbing, or rolling over in bed
- Difficulty sitting for long periods, or sitting evenly on both sides
- A sense of instability or catching in the pelvis
How Remix Medical Can Help
Physical examination maneuvers help, but no single test is definitive. The reference standard is a diagnostic injection: local anesthetic placed into the joint under fluoroscopic guidance. If your familiar pain substantially resolves, the joint is confirmed as the pain generator.
Our treatment options include:
- Fluoroscopically guided sacroiliac joint injection, both diagnostic and therapeutic
- Radiofrequency ablation of the lateral branch nerves supplying the joint, for durable relief
- Physical therapy referral targeting hip and core stabilization
- Chiropractic care through our in-house team when a mechanical component is present
- Medication management for inflammation and pain
| Approach | What it involves |
|---|---|
| Physical therapy + bracing | Targeted stabilization and a supportive SI belt |
| Medications | Anti-inflammatories for symptom control |
| Diagnostic + therapeutic injections | Confirm the SI joint as the source and calm it |
| Radiofrequency ablation | Longer-lasting relief when injections help but fade |
Relief from SI Joint Pain at Remix Medical
If months of sciatica treatment have not touched your pain, the joint may never have been examined.