Overview
Sacroiliac (SI) joint injections are fluoroscopically guided procedures that deliver local anesthetic and corticosteroid directly into or around the SI joint. They serve a dual diagnostic and therapeutic role: confirming the SI joint as the pain source (diagnostic) while simultaneously providing anti-inflammatory relief (therapeutic). The SI joint is responsible for an estimated 15–30% of chronic low back pain cases — yet is frequently overlooked, sometimes even after spinal surgery. Dr. Migdale's combined chiropractic and interventional background gives her a heightened awareness of the SI joint as a pain generator.
Why the SI Joint Is Missed
The SI joint does not appear prominently on routine lumbar MRI, which focuses on the disc-nerve interface. Without specific awareness of SI joint anatomy and pain patterns, clinicians may direct treatment at the lumbar spine while the true pain source remains untreated. Dr. Migdale evaluates all patients with low back and buttock pain for potential SI joint involvement using a combination of provocation tests and image-guided injection.
The Injection Procedure
SI joint injections are performed under fluoroscopic guidance with the patient lying on their abdomen. The skin is cleaned and numbed with local anesthetic. A needle is advanced under continuous X-ray visualization into the lower pole of the SI joint, and contrast dye confirms correct intra-articular position before medication is injected. The procedure takes approximately 20–30 minutes.
When SI Joint Injections Lead to Further Treatment
Injections with corticosteroid can provide weeks to months of relief. For patients whose pain returns consistently, lateral branch radiofrequency ablation of the nerves supplying the SI joint provides longer-lasting relief — often 12 months or more. For patients with refractory SI joint pain who do not achieve adequate relief from injections and RFA, minimally invasive SI joint fusion (Liberty-SI system) is available.