Peripheral Spondyloarthritis

Peripheral spondyloarthritis is a form of inflammatory arthritis that primarily affects the joints in the arms and legs, rather than the spine, causing pain, swelling, and stiffness that can significantly impact daily life.

Table of contents

• What is Peripheral Spondyloarthritis?
• Symptoms and Clinical Features
• Causes and Risk Factors
• Diagnosis
• Treatment Options
• Living with Peripheral Spondyloarthritis

What is Peripheral Spondyloarthritis?

Peripheral spondyloarthritis is a type of inflammatory arthritis (arthritis caused by an overactive immune system) that primarily affects joints outside the spine and pelvis. While spondyloarthritis as a family of diseases can affect different parts of the body, peripheral spondyloarthritis specifically targets the arms and legs rather than the back and spine^[1][2].

Healthcare providers classify spondyloarthritis into two main categories based on which parts of the body are most affected. Axial spondyloarthritis mainly affects the spine and the joints connecting the spine to the pelvis. In contrast, peripheral spondyloarthritis is characterized by inflammatory pain and arthritis in peripheral joints and tendons other than the spine^[2]. The condition gets its name from the predominant symptoms—whether they occur in the central axis of the body or in the peripheral limbs—which determines the specific diagnosis^[2].

Peripheral spondyloarthritis includes several specific conditions. Psoriatic arthritis is the most common form, where joint inflammation occurs alongside the skin condition psoriasis^[3]. Other types include reactive arthritis, which develops after certain infections, and enteropathic arthritis, which is associated with inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis^[4][5].

Some people may have both axial and peripheral symptoms simultaneously. When this happens, doctors determine the category based on which symptoms are most prominent^[2].

Symptoms and Clinical Features

The hallmark symptoms of peripheral spondyloarthritis include pain and swelling in the joints of the arms and legs. Unlike back pain that characterizes axial forms of the disease, people with peripheral spondyloarthritis experience their main symptoms in the large joints such as knees, or in smaller joints of the hands and feet^[4][6].

A distinctive feature of this condition is enthesitis, which means inflammation where tendons and ligaments attach to bones. Common sites for enthesitis include the heels and knees^[1][4]. This can cause significant pain, particularly in the Achilles tendon or under the heel.

Another characteristic symptom is dactylitis, which causes entire fingers or toes to swell, giving them a distinctive sausage-like appearance^[4][6]. This swelling can make it difficult to use your hands or walk comfortably.

Beyond joint symptoms, peripheral spondyloarthritis can affect other parts of the body. Eye inflammation, specifically a condition called uveitis, is common in people with spondyloarthritis^[4]. Some people also experience digestive problems, including diarrhea, especially if their condition is related to inflammatory bowel disease^[1]. Skin changes such as psoriasis may be present, particularly in those with psoriatic arthritis^[4].

Fatigue is another important symptom that many people with peripheral spondyloarthritis experience, which can significantly affect daily activities and quality of life^[8].

Causes and Risk Factors

The exact cause of peripheral spondyloarthritis is not fully understood, but it develops through the interaction of genetic and environmental factors^[4]. The condition is thought to be an autoimmune disease, meaning the body’s immune system mistakenly attacks healthy tissues, causing chronic inflammation in the joints^[1].

Genetics play an important role in peripheral spondyloarthritis. Many people with spondyloarthritis carry a gene called HLA-B27, which controls immune responses^[1][4]. However, having this gene does not mean you will definitely develop the disease. In fact, about 98% of people who carry the HLA-B27 gene never develop back pain or spondyloarthritis^[5]. Additionally, many other genetic variants have been identified that can increase disease risk^[4].

Family history is a significant risk factor. If you have a first-degree relative with spondyloarthritis or related conditions such as psoriasis, inflammatory bowel disease, or uveitis, you are at higher risk of developing the condition^[8].

Environmental triggers can also play a role. Reactive arthritis, one form of peripheral spondyloarthritis, develops after a urinary tract infection or an episode of infectious diarrhea caused by certain types of bacteria^[4][5]. Researchers have also hypothesized that bacteria may play a role in other variants of spondyloarthritis, typically without causing obvious infection^[4].

People with inflammatory bowel disease may develop spondyloarthritis, suggesting that certain disease mechanisms are shared between these conditions^[4].

Diagnosis

Diagnosing peripheral spondyloarthritis can be challenging, particularly when the characteristic extra-articular manifestations such as uveitis, psoriasis, or inflammatory bowel disease are absent^[10]. Formal classification criteria for peripheral spondyloarthritis were introduced in 2011, but diagnosis still relies on a rheumatologist’s judgment based on several factors considered together^[3].

Your doctor will typically begin with a thorough medical history and physical examination^[4][8]. They will ask about your symptoms, family history of spondyloarthritis or related conditions, and any recent infections.

Blood tests are commonly used to help with diagnosis. Your doctor may test for the HLA-B27 gene and measure markers of inflammation in your blood^[4][8]. However, spondyloarthritis should not be ruled out based only on negative laboratory results, as not everyone with the condition has positive test results^[12].

Imaging studies help look for evidence of inflammation and rule out other potential causes of your symptoms. The specific type of imaging study—whether X-ray, ultrasound, or MRI—will vary depending on your symptoms^[4][8]. If peripheral spondyloarthritis is diagnosed, your doctor may also recommend imaging of the sacroiliac joints to check for axial involvement^[12].

It’s important to note that spondyloarthritis cannot be ruled out based on a single symptom or test result. Healthcare providers need to consider the complete picture of your symptoms, family history, and test results together^[12].

Treatment Options

Treatment for peripheral spondyloarthritis depends on the severity of your illness and which specific form of the condition you have. The goal of treatment is to reduce pain and inflammation, prevent joint damage, and improve your ability to function in daily life^[4].

Nonsteroidal anti-inflammatory drugs (NSAIDs) are often the first-line treatment. These medications help reduce pain and swelling and should be used at the lowest effective dose with continued monitoring^[4][6][8]. If one NSAID is not effective after two to four weeks, your doctor may suggest trying another^[12].

Disease-modifying antirheumatic drugs (DMARDs) such as methotrexate or sulfasalazine may be used in patients with peripheral arthritis involving multiple joints or persistent inflammation in a single joint^[4][8][12]. These medications are not effective for treating spinal inflammation, but they can be helpful for peripheral joint symptoms^[4][8].

Biologics are second-line drugs that can be highly effective for peripheral spondyloarthritis. TNF inhibitors, IL-17A inhibitors, and other biologic medications are used when first-line treatments are not sufficient^[4][8]. However, it’s important to note that all biological treatments are currently off-label for patients with non-psoriatic peripheral spondyloarthritis, meaning they are not officially approved for this specific use^[3].

For specific joints that are severely affected, your doctor may recommend corticosteroid injections directly into the joint. Short-term oral corticosteroids may also be used in some cases^[12].

Physical therapy is an important part of managing peripheral spondyloarthritis. A physical therapist can work with you to develop an exercise program that maintains joint mobility and strengthens the muscles supporting your joints^[4][8].

Research has shown promising results for some patients. In one study of early peripheral spondyloarthritis, 82% of patients achieved sustained clinical remission following treatment with a biologic medication. After stopping treatment, 53% of responders remained in sustained and drug-free remission for periods ranging from 23 months to five years^[13]. However, patients with psoriasis or disease affecting multiple joints were more likely to experience relapse after stopping treatment^[13].

Living with Peripheral Spondyloarthritis

Managing peripheral spondyloarthritis involves more than just medications. Several lifestyle approaches can help you manage symptoms and improve your quality of life.

Regular, gentle exercise is essential for maintaining joint mobility and reducing stiffness. Low-impact activities such as walking, swimming, cycling, and yoga are excellent choices^[15]. Even a brief daily routine can make a significant difference. Focus on exercises that enhance flexibility and range of motion, and avoid high-impact activities that might stress inflamed joints^[15].

Diet may play a role in managing inflammation. While there is no single diet proven to cure peripheral spondyloarthritis, many people find that sticking with a healthy diet helps them feel better^[15][16]. Choose fresh vegetables, fruit, and whole grains. Limit red meat, sugar, soda, and other highly processed foods^[16]. Some people find turmeric helpful, as it contains curcumin, which has anti-inflammatory properties^[19].

Getting adequate sleep is crucial when living with peripheral spondyloarthritis. Pain can interfere with sleep, and lack of sleep can make you more sensitive to pain^[16]. Make sure you are taking your medications as directed, avoid caffeine late in the day, and limit screen time before bed^[16].

Managing stress is also important. Living with a chronic disease is stressful, and emotional stress can trigger symptom flares. Find healthy ways to manage stress that work for you, whether that’s meditation, yoga, spending time in nature, or being with pets^[16].

When symptoms flare up, heat therapy can provide relief. Getting into a hot shower or bath can help loosen up tight joints^[19]. When a shower or bath isn’t an option, try an electric heating pad draped over affected areas^[19]. Gentle stretches, even if you don’t have energy for more intense exercise, can also help ease pain and stiffness^[19].

Because peripheral spondyloarthritis can affect the feet, proper foot care is important. Always wear supportive, comfortable shoes. Consider seeing a foot specialist for custom insoles that can take pressure off certain parts of your feet^[18].

Around the house and at work, make adjustments to conserve your energy. Use long-handled tools when cleaning or gardening to avoid excessive bending and reaching. Sit down when possible during tasks, but avoid sitting for long stretches, as this can worsen fatigue. Don’t hesitate to ask for help when your energy is low^[18].