Eight Types of Spondylitis

Spondylitis is the inflammation of the vertebrae. How the medical community talks about this autoimmune and musculoskeletal disease has changed since new guidelines for diagnosis were established in the late 2000s. There are many types of the condition and still some disagreement about how to classify them. Spondylitis is normally diagnosed and treated by a rheumatologist.

Ankylosing Spondylitis

Ankylosing spondylitis is a chronic disease that causes inflammation of the spine, chest, and pelvis. Common features of this type include back pain and stiffness, and fusion of the small vertebrae in the spine can result. About half of people with ankylosing spondylitis have inflammatory bowel disease, and between 25 and 35 percent have acute anterior uveitis — swelling of the inside of the eye. Ankylosing spondylitis also increases the risk of spinal cord injury and vertebral fractures.

Psoriatic Spondylitis

Psoriatic spondylitis results from psoriatic arthritis, an autoimmune disease. The latter condition is not fully understood, though it seems to be caused by genetic and environmental factors. Most people with psoriatic arthritis experience symptoms in their fingers, and the wrists, ankles, and knees are often affected. About 20 percent of affected people have spinal involvement resulting in spondylitis.

Enteropathic Arthritis

Another form of spondylitis is enteropathic arthritis. It occurs in people with inflammatory bowel disease (IBD) and is the most frequent extra-gastrointestinal issue, affecting between 17 and 39 percent of people with IBD. Enteropathic arthritis is not well understood. Researchers believe that inflammation occurs due to a combination of predisposing genetic conditions and bacterial gut infections.

Reactive Arthritis

Reactive arthritis can affect multiple joints and cause spondylitis in the spine. This type is caused by a bacterial or viral infection in another part of the body, most commonly the intestines, urinary tract, or genitals. Reactive arthritis and resulting spondylitis is not common and usually resolves within 12 months. The pain tends to be in the lower back and is worse at night or first thing in the morning.

Undifferentiated Spondyloarthritis

When someone has a variety of symptoms that cannot be explained by a specific rheumatoid disorder, they are said to have undifferentiated spindyloarthritis. Some doctors do not see this as a separate type of spondylitis but relate it to psoriatic arthritis or reactive arthritis. Pain is often the only sign and may cause depression or anxiety and lead to a misdiagnosis of fibromyalgia.

Juvenile Spondyloarthritis

Juvenile spondyloarthritis is spondylitis of any type that affects someone younger than 16 years old. Though this is rare, one out of every six or seven cases starts in the teen years. Some studies suggest that those with juvenile spondyloarthritis may not be able to manage their disease as effectively as those with later onset, but others have much brighter outcomes. This type tends to be more severe, but treatments are advancing dramatically and will continue to do so.

Peripheral Spondyloarthritis

Peripheral spondyloarthritis is evidence of the evolving nature of spondylitis. Though peripheral spondylitis commonly causes inflammation in joints outside of the spine, almost all people who experience it get a diagnosis of spondylitis at some point in their lives, which indicates an overlap. Excluding people from treatment and research due to a lack of spinal involvement limits options for those with peripheral spondyloarthritis, which is why the classification is now changing.

Axial Spondyloarthritis

Axial Spindyloarthritis is a common term for spondylitis. This broad category overlaps with other types and effects the axial spine: the spine, chest, and pelvis. This wide-reaching category is an umbrella term that encompasses other types of the disease, including ankylosing spondylitis, enteropathic arthritis, and psoriatic arthritis.

Diagnosis and Treatment

Diagnosis of spondylitis is usually based on the results of a physical exam. The physician also obtains a full health history and may order blood tests or imaging scans to confirm or determine the extent of the disease and rule out other possible causes. Treatment consists of medication and physical therapy in addition to interventions aimed at the type of spondylitis. For example, in psoriatic arthritis, the treatment also focuses on any psoriatic skin patches, and reactive spondylitis treatment involves treating the underlying infection.

First Established Guidelines

The first guidelines for the treatment of spondylisis were established by the American College of Rheumatology in 2015. These guidelines specifically address when NSAIDs should and should not be used and indications and contraindications for systemic glucocorticoids. Physical therapy is almost universally recommended, and total hip replacements are supported when advanced hip arthritis is involved.