Back pain is one of the most common ailments in the United States today. In fact, according to the National Institute of Neurological Disorders and Stroke, roughly 80 percent of adults experience low back pain at some point in their lifetimes. Many of these cases are caused by injury or damage. However, some may be the result of another condition.
One such condition is ankylosing spondylitis (AS). This is a type of axial spondyloarthritis, which affects up to 1 percent of Americans, or about 2.7 million adults. Men are affected more often than women, though it may be less recognized in women. For the millions of Americans with chronic back pain, understanding this disease may hold the key to managing their pain.
AS is a progressive inflammatory disease. A form of arthritis, the disease causes swelling in your spine and nearby joints. Over time, the chronic inflammation can cause the vertebrae in your spine to fuse together, making your spine less flexible. Many people with the disease hunch forward because their extensor muscles, which allow extension, weaken. In advanced cases, a person with AS can’t lift their head in order to see in front of them.
AS primarily affects the spine and the vertebrae, specifically where tendons and ligaments connect to bone. Most people with the disease experience chronic back pain and loss of flexibility in their spine. However, AS can also affect joints outside the spine, including the shoulders, feet, knees, and hips. In rare cases, it can also affect organs and tissue.
AS does have one unique characteristic when compared to other forms of arthritis: sacroiliitis. This is inflammation of the sacroiliac joint, or the joint where your spine and pelvis connect. It’s a hallmark of people with AS, and isn’t common in people with other forms of arthritis.
Doctors don’t have a single test with which to diagnose this disease. In order to diagnose this disease, your doctor must exclude other possible explanations for your symptoms. To do this, your doctor first looks at your medical history, and then performs a physical exam and other tests.
To help understand your symptoms, your doctor will want to get your full health history. Your doctor will want to know:
Your doctor may want to conduct a physical exam. The exam allows them to find telltale signs and symptoms of AS. Your doctor may also have you do a few exercises or passively move your joints, so they can observe the range of motion in your joints.
Imaging tests give your doctor an idea of what’s happening inside your body. The imaging tests you need may include:
Lab tests your doctor may order include:
Make a list of all the questions you have for your doctor before you see them. Bring with you a timeline of your symptoms, any test results you may have, any medicine you may be taking, and known family history of medical conditions. Being prepared will help you make the best use of your time when you see your doctor.