For Patients

Understanding
SI Joint Pain

The sacroiliac joint is a common — and often overlooked — source of chronic lower back pain. Learn what it is, what causes it, and what a minimally invasive treatment looks like.

01 — Anatomy

What is the SI joint?

The sacroiliac (SI) joint connects your lower spine (sacrum) to your pelvis (ilium). You have two — one on each side — that help transfer weight between your upper body and legs.

01

Lower Back & Buttock Pain

SI joint pain most commonly presents as aching in the lower back, buttock, or hip — often on one side.

02

Activity-Related Symptoms

Pain often worsens when sitting for long periods, standing up, climbing stairs, or lying on the affected side at night.

03

Referred Discomfort

Some patients experience pain radiating into the groin or thigh, or notice stiffness and limited mobility in the hip and pelvis.

Sacroiliac joint · anatomy
02 — Causes

What causes SI joint pain?

SI joint dysfunction can develop gradually or result from a specific event. Injury, arthritis, pregnancy-related changes, or general wear and tear can all affect the joint's ability to absorb and transfer load properly.

Cause 01

Injury or Trauma

Falls, accidents, or sudden impacts can strain or damage the SI joint ligaments and surrounding structures.

Cause 02

Arthritis & Wear

Osteoarthritis and degenerative changes over time can reduce joint stability and increase pain with movement.

Cause 03

Pregnancy-Related Changes

Hormonal changes during pregnancy can loosen SI joint ligaments, sometimes resulting in lasting discomfort.

03 — Treatment

When is surgery considered?

Your doctor may consider SI joint fusion if conservative treatments — such as physical therapy, medications, or injections — have not provided enough relief. Only your doctor can determine the right treatment plan.

Step 01

Conservative Treatment First

Physical therapy, anti-inflammatory medications, and SI joint injections are typically the first line of treatment for months before surgery is considered.

Step 02

Diagnostic Confirmation

Your physician will use imaging and diagnostic injections to confirm the SI joint is the primary pain source before recommending fusion.

Step 03

Minimally Invasive Fusion

SI-Logix is designed as a minimally invasive procedure with a small incision, low-profile instrumentation, and an outpatient-capable setting in many cases.

Step 04

Recovery

Many patients are able to walk the same day as their procedure and return to light activities within approximately two weeks. Individual results may vary.

04 — Next Steps

Talk to a provider near you

Contact us to learn about physicians in your area who use the SI-Logix system, or get answers to common questions on our FAQ page.