What Is the Difference Between Ankylosing Spondylitis and Sciatica?

What Is the Difference Between Ankylosing Spondylitis and Sciatica?

Uveitis (eye inflammation)
Sciatica symptoms include:
Sharp, burning pain that radiates from your lower spine down through your buttocks and the back of your leg, usually only on one side.
Pain that is more felt in your lower leg compared to your lower back
Pain that worsens when you cough or sneeze
Pain that gets worse as the day goes on
Numbness, tingling, or muscle weakness in the affected leg
Difficulty controlling your bowels or bladder (if this is the case, you should seek immediate medical care)
One important distinction that can help you determine what you’re dealing with is the onset of the pain: Did it come on quickly, or has it slowly gotten worse over time?
Dr. Gupta notes that with sciatica, there tends to be a clear incident that triggered the pain. “[A person with sciatica may have] twisted their back, or bent in the wrong way,” he says. “Sciatica is very acute, like they were fine yesterday and today they’re feeling horrible. But ankylosing spondylitis comes on insidiously, they kind of have this little backache; now it’s getting worse.”
Does Ankylosing Spondylitis Cause Sciatica?
Although both conditions can cause back pain, one ailment doesn’t really cause the other one to occur, except in very unusual cases.
“Ankylosing spondylitis causing sciatica is not impossible, but it’s a very rare occurrence,” explains Dr. Gupta. “The vice versa is not true — sciatica doesn’t cause ankylosing spondylitis.”
He notes that sacroiliitis — inflammation of the sacroiliac joint, which is where the spine connects with the pelvis and is a common feature of ankylosing spondylitis — causing symptoms of sciatica have been reported in a handful of cases.
There isn’t necessarily any specific cause of ankylosing spondylitis, though genes are thought to play a role . There is one known genetic marker in particular, called the HLA-B27 gene , that is associated with an increased risk of ankylosing spondylitis. (However, you can also have AS without having this gene.)
Research suggests that AS can be triggered by something in your environment, such as an infection. As with other inflammatory conditions, AS is likely caused by a combination of genetic and environmental factors.
Understanding Sciatica
How Common is Sciatica?
Sciatica is a fairly common condition. According to the Cleveland Clinic, about 40 percent of U.S. adults experience sciatica sometime in their life. Some people, however, are more at risk of experiencing sciatic pain because of their lifestyle and other health conditions.
Outlook for Sciatica
Although sciatica can cause intense pain, it isn’t necessarily something that requires serious medical intervention. Dr. Gupta says the majority of sciatica cases resolve within 90 days. That said, Dr. Gupta also notes the importance of seeing a doctor if you suspect you could have sciatica, as it can cause permanent nerve damage if left untreated.
“If the back pain is the more prominent feature and if it is not improving with more conservative measures, go see a doctor,” he says. “And then consider a rheumatology referral to make sure there is nothing happening beyond run-of-the-mill sciatica.”
Risk Factors for Sciatica
There are certain medical conditions and lifestyle habits that increase your risk for developing sciatica.
Previous Injury: Having a slipped disk in your back can cause pressure on the sciatic nerve. Similarly, other back injuries can cause you to develop sciatica.
Weight: People who are overweight can also be at risk for sciatica because of the stress put on the spine.
Job: There’s reason to believe that a labor-intensive job that requires you to twist your back or carry heavy loads might increase your risk for sciatica. That said, the Mayo Clinic also notes that there isn’t conclusive evidence of this link.
Diabetes: Having diabetes increases your risk of nerve damage, which can make it more likely for you to have sciatica.
Osteoarthritis: According to the Cleveland Clinic , as osteoarthritis breaks down the cartilage that cushions your bones, your body can grow bone spurs to try and repair the loss. It’s possible for these bone spurs to form in your spine and press on your sciatic nerve.
Weak core: Having well-developed back and core muscles helps support the spine, which in turn decreases your risk for sciatica.
Age: Age-related changes in the spine can be a common cause for sciatica, according to the Mayo Clinic.
Smoking: Nicotine can damage spinal tissue and weaken bones, meaning people who smoke may be more likely to develop sciatica.
How Sciatica Is Diagnosed
If you suspect you may have sciatica, the best thing to do is to see a health care provider. They may do a physical assessment, which could include:
Walking: You may be asked to walk on your toes or heels to see if the pain worsens, which can indicate sciatica.
Straight Leg Test : According to the University of Maryland School of Medicine, the straight leg raise test can be used to help determine if someone has sciatica. If your doctor asks you to do this, you’ll lie with one leg down, while the other leg is kept straight up and raised by the examiner. If raising the leg between 30 and 70 degrees causes pain to occur and radiate down the leg, that can indicate that you may have sciatica. Your health care provider may also perform this test with you sitting down and stretching the sciatic nerve by extending the knee. If you feel pain that radiates to below the knee, this could be a sign of sciatica.
In some cases, such as instances where sciatica doesn’t resolve within a normal timeframe, your doctor may order additional tests . These could include:
Spinal X-rays: If your sciatica pain doesn’t lessen after a certain amount of time, your doctor may order X-rays to see if there are bone spurs that are pressing on a nerve.
MRI: Similarly, your doctor may have you do an MRI to get a detailed image of your bone and soft tissues, which can allow them to see things like herniated disks.
Electromyography (EMG): Your health care provider may want you to get this test, which measures electrical impulses produced by the nerves and responses of your muscles. With regards to sciatica, it can confirm nerve compression caused by things like herniated disks.
Myelogram: This test involves a dye being injected into your spinal canal through your lower back. It allows for the doctor to get a clear look at whether there is anything pressing against your nerves or spinal cord.
How Sciatica Is Treated
If your health care provider diagnoses you with sciatica, there are a number of treatment options they may recommend.
Ice/Heat therapy: The Mayo Clinic recommends applying an ice pack to the painful areas for about 20 minutes multiple times throughout the day. After a few days of this, you can try using a heating pad on the lowest setting. You can try alternating warm and cold packs to see if this provides any relief.
Physical therapy: Your health practitioner may recommend physical therapy to treat your sciatic pain. A physical therapist can perform and teach gentle stretches or exercises that will help build your core strength, which can help relieve your sciatic pain. They may also recommend light exercise, like walking or swimming.
Medications: Some of the medications used to treat sciatica can include muscle relaxants, anti-inflammatory drugs, or painkillers, according to Dr. Kaplan.
Spinal injections: It’s possible that your doctor might recommend getting epidural injections of a corticosteroid medication in the area around the nerve root that is causing you trouble. This can help suppress inflammation around the irritated nerve and reduce pain.
Surgery: In severe cases, your doctor may consider surgery to treat sciatica. A severe case would be if you experience loss of bladder or bowel control or significant weakness, or if no other therapy/treatment has improved your condition. A surgeon may be able to remove the bone spur or portion of the disk that’s causing pain, but as Dr. Kaplan notes, surgery is a last resort.
Understanding Ankylosing Spondylitis
How Common Is Ankylosing Spondylitis?
Estimates vary depending on which studies you look at, but AS is not as rare as you might think. According to the Spondylitis Association of America , spondyloarthritis (which includes ankylosing spondylitis as well as other forms of arthritis) affects 3.2 million Americans, or about one in 100. And these numbers may be an underestimate, since AS tends to be misdiagnosed or people experience significant delays in getting a proper diagnosis.
Risk Factors for Ankylosing Spondylitis
There isn’t one specific cause of ankylosing spondylitis, but there are some groups who are more at risk for developing the disease than others.
Sex: Ankylosing spondylitis has historically been considered a disease that predominantly affects men. However, more recent data suggests that while AS is more commonly diagnosed in males than in females, it does affect females and is more evenly distributed among the sexes than previously thought.
Age: Symptoms of ankylosing spondylitis usually begin between before age 45 and commonly start in the teens, twenties, and thirties.
Family history: People who have the HLA-B27 gene in their family are at greater risk of developing ankylosing spondylitis. That said, it is possible for people who don’t have this gene to develop the disease. And on the flip side, people who do carry the gene don’t always develop ankylosing spondylitis.
How Ankylosing Spondylitis Is Diagnosed
If you are concerned that your back pain might be caused by ankylosing spondylitis, you should see a doctor. You may need to start with a general practitioner for initial testing, who would likely refer you to a rheumatologist, which is a doctor who treats musculoskeletal disease and systemic autoimmune conditions. There are several things that your health care provider might do in order to diagnose you with ankylosing spondylitis .
A physical exam. The doctor will look for signs of spine fusion, inflammation, and limited range of motion in your spine and your other joints.
Image testing. Your rheumatologist may order imaging tests, such as X-rays and MRIs, to get a better look at what’s happening with your spine as well as your other joints.
Assess personal and family medical history. Your health care provider will likely ask you some questions about your own medical history as well as your family history. They will ask about the nature of your back pain and other symptoms: when they started, what makes them feel worse or better, etc.
Blood work. A doctor may order blood tests to get more information about whether you are at risk of developing ankylosing spondylitis. These may include testing for the HLA-B27 genetic marker and looking for elevated levels of inflammation in the blood — erythrocyte sedimentation rate (ESR, or sed rate) or C-reactive protein (CRP).
Read more here about how ankylosing spondylitis is diagnosed .
Outlook for Ankylosing Spondylitis
Ankylosing spondylitis can cause pain that can be debilitating and have a big impact on patients’ sleep, mood, ability to work, and overall quality of life. It is not a life-threatening condition.
“The outlook for AS is very good if addressed early in the disease course,” Brett Smith, DO, rheumatologist with Blount Memorial Physicians Group in Alcoa, Tennessee, previously told CreakyJoints . “With appropriate comprehensive treatment, including physical therapy and exercise, NSAIDs, and biologics, many people have preserved function and minimal pain.”
That being said, some of the comorbidities associated with AS can be concerning. People with AS may be more likely to develop certain heart problems and osteoporosis. They may also be at risk for other inflammation-related conditions, such as inflammatory bowel disease (IBD), psoriasis, and uveitis (eye inflammation), as well as mental health conditions like depression.
How Ankylosing Spondylitis Is Treated
There’s no cure for ankylosing spondylitis, but there are different types of medication that can help relieve symptoms, reduce inflammation, and possibly slow the progression of the disease. Treatment for AS may include:
NSAIDS. Short for nonsteroidal anti-inflammatory drugs, these are considered first-line treatments for AS. Medications in this category include over-the-counter drugs such as ibuprofen or naproxen, as well as prescription versions of NSAIDs. If they don’t work well enough to reduce AS symptoms, then doctors typically recommend advanced therapies, such as biologic drugs.
Biologics. Biologics are medications (given by injection or IV infusion) that target specific parts of your immune system to reduce inflammation.
Steroids. Corticosteroids are not recommended for long-term use because they can cause many different side effects, but they are sometimes recommended to help manage painful flares, or periods of increased disease activity.
Exercise regularly and attend physical therapy. In addition to following a treatment plan from your doctor, regular exercise and physical therapy can help you manage pain from ankylosing spondylitis. If you experience stiffness and pain in the morning, doing flexibility and range-of-motion exercises when you wake up may help. You can also try deep-breathing exercises, balance exercises, and aquatic exercises.
Get enough sleep. Getting a good night’s rest can help you manage your AS symptoms. However, pain from AS can make it very challenging to get high-quality sleep; many people with AS report “painsomnia” that interrupts their sleep. Make sure to tell your doctor if you are having difficulty sleeping. You may need adjustments to your medication regimen or try complementary practices, like meditation, to help improve your sleep.
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