Sacroiliac (SI) Joint Dysfunction

Common Symptoms

• Pain centered over one side of the lower back or buttock, near the dimple above the hip
• Pain that can radiate into the groin, hip, or upper thigh
• Pain that worsens with prolonged sitting, standing on one leg, or transitional movements like standing up from sitting
• Pain during pregnancy or postpartum, when SI joint dysfunction is especially common

Why It Happens

The SI joints normally allow only small amounts of movement, and dysfunction can develop from a fall, pregnancy-related ligament laxity, repetitive asymmetric loading, or, in some cases, an underlying inflammatory condition affecting the joint.

Why It Can Become Persistent

Because the SI joints bear load with nearly every position change — sitting, standing, walking — ongoing daily activity can keep reproducing irritation unless the underlying mechanical or postural factors are addressed.

Who Commonly Gets It

SI joint dysfunction is especially common during and after pregnancy, after a fall onto the buttock, and in people with asymmetric leg length or gait patterns.

How It Is Usually Diagnosed

Diagnosis relies on a cluster of specific provocative physical exam tests, since imaging often looks normal; a diagnostic injection into the joint is sometimes used to confirm the SI joint as the specific pain generator.

Traditional Treatment Options

• Physical therapy: Addressing pelvic and core stability is a well-established first-line treatment.
• SI joint belt or brace: Can provide symptomatic support, particularly during pregnancy.
• NSAIDs: Sometimes used for symptom control.
• Corticosteroid injection into the joint: Can provide both diagnostic confirmation and symptom relief.
• Radiofrequency ablation or surgical fusion: Reserved for more persistent cases that don't respond to conservative treatment.

Why Someone Might Start Looking for Another Option

When physical therapy and bracing don't fully resolve symptoms, and before considering more invasive procedures, people look for additional non-invasive options, including shockwave therapy.

Where Shockwave Therapy May Fit

A sham-controlled randomized trial found shockwave therapy produced significantly lower pain scores at 4 weeks compared with sham treatment, while the sham group showed no significant improvement. A separate randomized trial in postpartum patients with SI joint dysfunction found shockwave therapy produced better short-term disability scores than manual therapy at 1 week, with both approaches similarly effective by 2 weeks, and the combination of the two producing the highest overall improvement rate. This is genuine trial-level evidence, though from small, short-term studies.

How Shockwave Treatment Works for This Area

Acoustic pressure waves are applied over the SI joint region, generally alongside — not instead of — physical therapy addressing pelvic and core stability.

What the Treatment Feels Like

Most patients describe a firm tapping or pressure sensation over the lower back/buttock area; your provider will discuss what to expect.

What Happens During Your First Visit

Your visit begins with a provider evaluation focused on your history and a physical exam relevant to your complaint. If shockwave therapy is determined to be clinically appropriate, your first treatment can typically be provided the same visit. See our What to Expect page for the full walkthrough.

Who May Not Be Appropriate

• Anyone who has not yet had a medical evaluation to confirm the SI joint as the pain source
• Pregnancy, in the treatment area, unless specifically cleared by your provider (despite SI dysfunction being common in pregnancy, treatment timing needs individualized guidance)
• Active infection, open wounds, or certain bone/spine conditions at the treatment site
• Certain circulatory, neurological, or bleeding-related conditions, per your provider's screening

This list is not exhaustive. Your provider will screen for contraindications during your evaluation.