Overview

Sacroiliitis is a medical condition characterized by inflammation of one or both of the sacroiliac (SI) joints, which are located at the junction where the lower spine connects to the pelvis. These joints play a crucial role in transferring weight between the upper body and the legs, providing stability and flexibility to the pelvis. Inflammation of these joints can lead to pain in the lower back, buttocks, or even down the legs, often making everyday activities like standing, walking, or climbing stairs uncomfortable. Sacroiliitis is not a disease itself but rather a symptom of various underlying conditions, including different types of arthritis, infections, and injuries. The condition can be acute or chronic and may significantly affect quality of life if left untreated.

Causes

There are several possible causes of sacroiliitis, often related to inflammation, mechanical stress, or infection. Common causes include:

• Ankylosing Spondylitis: A type of inflammatory arthritis that commonly affects the spine and sacroiliac joints, leading to chronic inflammation.
• Psoriatic Arthritis: An inflammatory arthritis associated with psoriasis that can affect the SI joints.
• Reactive Arthritis: Joint inflammation that develops after an infection elsewhere in the body, sometimes involving the sacroiliac joints.
• Rheumatoid Arthritis: Although more commonly affecting peripheral joints, it can also cause sacroiliitis in some cases.
• Pregnancy: Hormonal changes and added stress on the pelvis during pregnancy can loosen the ligaments around the SI joints, causing inflammation.
• Trauma or Injury: A fall, car accident, or sudden impact can directly injure the sacroiliac joints, leading to inflammation.
• Infections: Though rare, bacterial infections such as tuberculosis or brucellosis can cause sacroiliitis.
• Degenerative Joint Disease: Age-related wear and tear or osteoarthritis can also affect the sacroiliac joints.

Symptoms

The primary symptom of sacroiliitis is pain, which may vary in intensity and location depending on the cause and severity. Common symptoms include:

• Lower Back Pain: A deep, aching pain often located near the lower back or buttocks.
• Buttock or Thigh Pain: Pain may radiate to the buttocks, groin, or back of the thighs, sometimes mimicking sciatica.
• Worsening Pain with Activity: Activities like standing, climbing stairs, running, or long periods of sitting may worsen the pain.
• Morning Stiffness: Stiffness and pain may be worse after waking up and improve with movement throughout the day.
• Limited Range of Motion: Difficulty in bending, twisting, or moving the lower back due to pain and stiffness.
• Localized Tenderness: Tenderness when pressing over the sacroiliac joints.
• Swelling or Warmth: In cases caused by infection or acute inflammation, there may be visible swelling or warmth over the joints.

Diagnosis

Diagnosing sacroiliitis involves a combination of clinical examination, patient history, and imaging studies. The diagnostic process typically includes:

• Medical History: A doctor will inquire about the onset, duration, and pattern of pain, as well as any associated conditions like psoriasis, inflammatory bowel disease, or recent infections.
• Physical Examination: Specific physical tests such as the FABER (Flexion, Abduction, and External Rotation) test or Gaenslen’s test can help provoke SI joint pain and assist in diagnosis.
• Imaging Studies:
• X-rays: May reveal joint space narrowing, sclerosis, or erosions in the SI joints.
• MRI (Magnetic Resonance Imaging): Highly sensitive for detecting early inflammation and soft tissue involvement around the sacroiliac joints.
• CT (Computed Tomography) Scans: Can provide detailed bone imaging, useful in chronic or advanced cases.
• Blood Tests: Tests for inflammatory markers like ESR and CRP, HLA-B27 genetic testing (for ankylosing spondylitis), or screening for infections may be performed.
• Joint Injections: Diagnostic injections of anesthetic into the SI joint can help confirm the source of pain if symptoms improve temporarily.

Treatment

The treatment of sacroiliitis focuses on reducing inflammation, relieving pain, and improving joint function. Treatment strategies are usually tailored based on the underlying cause and severity of the condition.

Non-Surgical Treatments

• Medications:
• Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): First-line treatment to reduce inflammation and relieve pain.
• Corticosteroids: Oral or injectable steroids may be used for severe inflammation.
• Biologic Agents: For autoimmune conditions like ankylosing spondylitis, biologics such as TNF-alpha inhibitors may be prescribed.
• Antibiotics: If sacroiliitis is caused by infection, appropriate antibiotic therapy is initiated.
• Physical Therapy: Tailored exercise programs focusing on strengthening the core, improving posture, and increasing flexibility.
• Heat and Ice Therapy: Applying heat or cold packs to the affected area to reduce pain and inflammation.
• Assistive Devices: Temporary use of canes or braces to reduce joint strain during flare-ups.

Interventional Treatments

• Sacroiliac Joint Injections: Corticosteroid injections directly into the SI joint can provide significant pain relief in selected cases.
• Radiofrequency Ablation (RFA): A procedure that uses heat to disrupt nerve signals, reducing chronic pain.

Surgical Treatment

• Surgery, such as sacroiliac joint fusion, is considered only in severe, refractory cases where conservative management fails to relieve symptoms.

Prognosis

The prognosis of sacroiliitis depends on the underlying cause and response to treatment. Many patients with mild to moderate sacroiliitis experience significant improvement with a combination of medications, physical therapy, and lifestyle adjustments. Conditions like ankylosing spondylitis may require ongoing management but can often be well-controlled with modern treatments such as biologic therapy.

Chronic or untreated sacroiliitis can lead to persistent pain, reduced mobility, and impaired quality of life. Early diagnosis, appropriate treatment, and regular follow-up are key to preventing long-term complications. With proper care, many individuals with sacroiliitis can maintain an active, functional lifestyle and minimize flare-ups.