What Is Sacroiliitis?

Sacroiliitis is an inflammation of the joints that is painful, from causing pain in the spine to the pelvic area (sacroiliac joints). This causes pain in the lower back, butt and legs.¹

Importance of Sacroiliitis in the musculoskeletal system

The sacroiliac joints are some of the biggest joints in the body and are used every time you move your hips. Sacroiliitis occurs when something irritates and or damages one or both of the joints, leading to inflammation and making you feel pain in your lower back and butt.^1,2

Anatomy of the Sacroiliac Joint

Overview of the sacroiliac joint

The sacroiliac joint is formed between the sacrum and the ilium.²

Function and role in the body's movement

The main function of the joint is to bear the weight of the axial skeleton and spread the weight to the hip bones. This weight can then be distributed between the two femurs in a standing position or the ischial bones in a seated position.²

Causes of Sacroiliitis

Anything that causes inflammation in your joints can cause sacroiliitis, including:^1,3,4

Inflammatory causes

• Ankylosing spondylitis - this is arthritis affecting the joints in the spine 
• Psoriatic arthritis - this is a combination of psoriasis and arthritis, causing you to have arthritis symptoms in the joints and psoriasis (flaky and scaly patches) in the skin 

Non-inflammatory causes

• Trauma -  traumatic injury, such as a fall or car crash that affects the lower back, butt, lugs or hips can cause an inflammation
• Infection - infection in the sacroiliac joints or urinary tract infection (infection) can also cause inflammation
• Pregnancy - hormone relaxin can lead to relaxation, stretching and widening of the joints. Increased weight during pregnancy can cause extra stress on the joints 

Symptoms and Clinical Presentation

• Lower back pain and discomfort
• Stiffness and reduced range of motion in the morning
• Radiating pain patterns from the lower back to the butt^1,4

Diagnosis of Sacroiliitis

Medical history and physical examination

When going to your appointment, your doctor may ask you about your medical history and conduct a physical examination. The doctor will ask you about your diet, sleeping patterns and your exercise routine. The doctor will also ask if you have a history of trauma, infections, or any inflammatory diseases.⁵

Imaging studies

To check the health of the bones, the doctor may ask you for imaging tests:^1,3,5

• X-rays
• MRI
• CT scans

Trigger Tests

To better understand your pain, the doctor may also ask to do provocation tests (trigger tests), including:⁵

• Distraction test
• Gait patterns
• Thigh thrust test
• Sacral thrust test
• Compression Test
• Gaenslen’s test
• Fortin Finger Test
• FABER (flexion, abduction and external rotation)
• Palpitation test

Treatment Options

Medications

• Nonsteroidal anti-inflammatory drugs (NSAIDs) - these are medications that can help to relieve some pain, for example, aspirin, ibuprofen and naproxen
• Corticosteroids - prescription medication to relieve inflammation and pain, that can also be directly injected into the affected joint 
• Muscle relaxers - prescription medications that are used to treat muscle pain, by stopping the nerves from sending pain signals to the brain^2,3,4,5

Other ways

• Physical therapy and exercise - can help to strengthen and stabilise the structure of the pelvic joints and bones. 
• Surgical interventions (in severe cases) - when none of the treatments work, then surgery is used as a last resort. Your doctor would permanently tighten the joint together using surgical screws

Lifestyle Management

To help you manage sacroiliitis, it is important to follow a healthy lifestyle, by following a diet and creating an exercise plan that is best for you. Some of these choices will include avoiding and or stopping smoking and making sure you exercise on a daily basis through low-impact exercising.¹

Prognosis

If you have inflammatory arthritis, then it is possible pain from the joints will be permanent and cause you chronic pain. Most people with sacroiliitis can be given medication to treat the cause and to manage their symptoms, physical therapy is recommended.^1,2

Complications

If it is not treated soon enough, the pain from sacroiliitis can affect your ability to move, causing you to have chronic back and hip pain. Also, it causes you to have muscle wasting.¹

Research and Advancements

Currently, only medication and physical therapy are mostly in use for people with sacroiliitis, but in recent years scientists have developed a treatment called LinQ, which is a device that is surgically inserted to fuse and stabilise the joints to reduce pain. It is less invasive than joint fusion, causing less trauma and a faster recovery time. Studies show patients to have massive relief and could carry out their daily tasks. But, there is a success rate of 78%.^6,7

Summary

Sacroiliitis is an inflammation that affects the joint where the spine and the pelvis meet, causing you to have lower back pain. Especially, making it difficult for you to move and use your body. However, it is possible to manage your symptoms, with, for example, physical therapy and in more severe cases with the use of minimally invasive surgery. New therapies are always being researched as they can help to better manage or even treat different conditions.