From healthcentral.com
Usually the first step in imaging for PsA, these scans can help determine the level of damage in your bones and joints
If you’re experiencing recurring and increasing joint pain, especially if you have the skin condition known as psoriasis, your doctor may have mentioned the possibility of psoriatic arthritis (PsA), a chronic, inflammatory disease that involves the joints and entheses—where tendons and ligaments connect to bone. Psoriatic arthritis can start at any age, including in childhood, according to the National Psoriasis Foundation. The condition affects about 30% of those with psoriasis but can develop even if you don’t have that issue.
Finding out whether you have PsA—or if the condition has advanced—will involve multiple strategies for diagnosis, including a physical exam and talking about family history, as well as imaging tests like ultrasounds, MRIs, and X-rays.
“Imaging such as X-rays can help us see any potential damage in the bones and joints from psoriatic arthritis,” says Anca Askanase, M.D., professor of medicine in the division of rheumatology at Columbia University College of Physicians and Surgeons in New York City. “In some cases, you may be able to see bone changes without imaging, such as in the hands and feet, but even then, you would use an X-ray to assess the level of damage.”
The Role of X-Rays In Psoriatic Arthritis
According to research in the journal Dermatology and Therapy, early detection of joint damage is important in PsA because it can lead to treatment that can slow the progression of the condition, and help you maintain function.
Those researchers suggest that screening tools like MRIs and ultrasounds can assist in determining the severity of damage, but that X-rays represent a readily available first step for evaluating bone and joint involvement.
“Conventional radiography [like an X-ray] is the most commonly used imaging technique for assessing structural damage in PsA,” researchers note. “Radiographs are especially useful in detecting bone erosion and/or new bone formation, which tend to be seen in later stages of the disease, and can help visualize soft tissue swelling suggestive of dactylitis.”
Dactylitis is a condition involving inflammation of the fingers or toes that results in swelling, pain, and redness, and PsA is one of the common causes for this, along with infections, gout, and other types of arthritis. An X-ray that identifies joint damage and leads to treatment may be able to reduce the intensity and progression of dactylitis, the researchers add.
Another advantage of X-rays for PsA is the way the imaging can determine whether joints of the spine are involved, particularly through new bone formation, according to Orrin Troum, M.D., rheumatologist at Providence Saint John’s Health Center in Santa Monica, CA.
“Extra bone tissue on the vertebrae, sometimes called ‘bone spurs’ are often seen with conditions that involve inflammation, such as PsA, ankylosing spondylitis, and osteoarthritis,” he says. “These bone spurs can lead to problems like limiting your range of motion, pain, stiffness, and nerve compression.”
The risk of bone spurs increases with disease progression and these can occur anywhere in the body for those with PsA, according to research in Arthritis Research & Therapy. That study looked at the prevalence of both bone spurs and bone loss in those with PsA and found that both are common, particularly at places where tendons attach to bone.
There is a limitation of X-rays for PsA, however. Dr. Troum says that this type of imaging is not as effective for seeing changes during early stages of the condition. That means if you’ve just been diagnosed with PsA and don’t have many symptoms, you may need additional imaging beyond X-rays to see whether there’s joint or bone damage that’s starting, he adds.
Monitoring Disease Progression With X-Rays
Another way that X-rays are used in PsA is to assess whether the condition is progressing or if treatment has slowed the rate of damage, says Dr. Askanase.
“Regular monitoring of psoriatic arthritis is crucial because it can help prevent some degree of long-term damage,” she says. “It can also give your health provider essential information on whether you’re responding to a specific medication or if your treatment may need to change.”
PsA progression is different for everyone, but in the later stages you may see joint deformity and reduced range of motion. Fortunately, treatment can keep most people from progressing to that point—as well as lowering risk of complications—but it requires some vigilance and regular check-ups, Dr. Askanase adds.
Other Imaging Techniques for Psoriatic Arthritis
Although X-rays are helpful, and will likely be the first step for imaging, there are other imaging options that can provide more information about what’s happening with your bones and joints when you have PsA.
Bone Scans. Also known as bone scintigraphy, these scans can show bone damage and disease in multiple areas and the scans tend to be more sensitive than X-rays; because of this, they may be useful for detecting early changes when PsA is just starting.
Computed Tomography (CT) Scans. This type of scan shows bone damage and inflammation in PsA and they’re especially useful for evaluating the pelvis, spine, and shoulder girdle—areas that may not be as clear with an X-ray.
Magnetic Resonance Imaging (MRI). While X-rays are focused on bones and joints, an MRI can detect inflammation in your soft tissues, like tendons and ligaments. That makes it easier to assess whether you have early signs of PsA.
Ultrasound. Using high-frequency sound waves, ultrasounds are beneficial for detecting early indications of joint damage due to inflammation, and they may also be used to assess disease progression.
Imaging choice will usually depend on your health team’s recommendation and what X-ray results have shown as areas of concern, says Dr. Troum.
Are There Side Effects of X-Rays for PsA?
However, the researchers note that this is only a concern with very frequent X-rays, or with pregnant women and young children. If you have regular X-rays, you may want to discuss radiation exposure with your doctor, suggests Dr. Troum. In some cases, you might be able to switch to different imaging without that minor exposure, such as ultrasounds.
Preparing for an X-Ray
Instructions for X-ray preparation can differ between providers, based on where you’ll be scanned on the body, but in general, Cleveland Clinic suggests you may be asked to:
Avoid using creams, lotions, or perfume since these can cause shadows on your X-ray.
Remove metal objects like jewellery or hearing aids.
Stop eating or drinking several hours beforehand, if an X-ray involves the torso.
Wear comfortable clothing or change into a gown for the X-ray.
Cleveland Clinic also recommends telling your healthcare provider about any allergies or medications you’re taking, and whether you’re pregnant or breastfeeding.
Bottom Line
Whether you’ve just been diagnosed with PsA or you’ve had psoriasis for years and suspect it might be advancing toward PsA, X-rays can be an important part of taking care of your health and staying on top of the condition, says Dr. Troum.
“Like any aspect of psoriatic arthritis, it’s a good idea to see your doctor if you’re experiencing changes in symptoms like pain and stiffness, but it’s also helpful to have regular appointments based on your doctor’s recommendation about how often you should be checked,” he says. “The earlier you can identify a problem, the sooner you can treat it and the less likely it will be to progress into a more serious issue.”
Elizabeth Millard is a journalist specializing in health, wellness, fitness, and nutrition. Her articles have appeared in SELF, Men’s Health, CNN, MyFitnessPal, and WebMD, and she has worked on patient education materials for Mayo Clinic and UnitedHealth Group.
https://www.healthcentral.com/condition/psoriatic-arthritis/psoriatic-arthritis-radiology
