What is synovitis? Causes, symptoms, treatments

Maybe you recently ramped up your weekly running mileage or increased the intensity of your cycling routine, and now you're managing a knee that feels stiff, swollen, and achy. In many cases, that reaction has a name: synovitis.

“Synovitis refers to irritation of the synovial membrane — the tissue that lines your joints and helps produce lubricating fluid that helps them move smoothly and comfortably,” explains Tyler Boyd, PT, DPT, a physical therapist with Hinge Health. Any joint in your body that has a synovial membrane can develop synovitis, but it most commonly affects knees, hips, shoulders, elbows, and ankles. 

While the word may sound intimidating, synovitis is often your body’s way of responding to increased demand. It commonly shows up when you’ve done more than your joints and surrounding soft tissues (ligaments, tendons, and muscles) are ready for. But synovitis is very treatable, often improving with simple, at-home treatments, such as targeted exercises, movement modifications, and lifestyle changes.

Learn more about synovitis, including how to treat and prevent it, especially with targeted exercises recommended by Hinge Health physical therapists.

Symptoms of synovitis

What does synovitis feel like? “You may notice swelling and discomfort when moving the joint,” says Dr. Boyd. When fluid builds up inside a joint, it can increase pressure, leading to joint stiffness and pain. That swelling can also temporarily reduce your range of motion. 

Common symptoms include:

• Swelling around the joint

• Tenderness

• Warmth

• Mild redness

• Stiffness after waking up

Causes of synovitis

Synovitis can happen when a joint experiences more load than it’s currently prepared to handle. If you’re active, it can be due to overuse, and it usually resolves once you scale back a bit and let your body recover. Sometimes it’s due to a more chronic condition, like arthritis. But even then, synovitis often gets better with some simple self-care strategies, Dr. Boyd explains. 

Some common triggers include:

• Increasing activity intensity or frequency too quickly. If you quickly ramp up hours on the pickleball court, cycling intensity, or any exercise with repetitive movements, your joint may react with temporary inflammation. “We often see synovitis in active people who’ve increased activity without building up gradually,” says Dr. Boyd.

• Arthritis. Synovitis can be part of osteoarthritis (which often occurs naturally with age),  rheumatoid arthritis (an autoimmune condition and inflammatory arthritis), and gout (an inflammatory arthritis). With osteoarthritis, changes in joint cartilage can increase sensitivity and fluid production. With inflammatory arthritis, such as rheumatoid arthritis or gout, the immune system drives joint inflammation. All of these can lead to a synovitis flare.

• Injury or trauma to the area. You can develop synovitis after an injury, whether it’s a sprain or strain, or direct impact — like falling on your knee. “These can all cause swelling that leads to inflammation and irritation of a joint,” explains Dr. Boyd. 

• Infections. While not as common, certain infections — including the bacteria that leads to Lyme disease — can cause joint inflammation. Transient synovitis, usually seen in children, may occur after a viral illness.

What’s the difference between synovitis in different joints?

Synovitis can occur in any major joint — including your knees, ankles, hips, shoulders, or wrists. How it feels and what tends to trigger it often depends on the joint involved. 

Here’s how it commonly shows up in different areas:

• Knee synovitis. “This is where we tend to see synovitis most often,” says Dr. Boyd. It commonly appears in active people who’ve recently increased high-impact activities, including activities such as running or tennis, or even low-impact activities like hiking. Knee synovitis can also accompany osteoarthritis flare-ups.

• Hip synovitis. Like the knee, hip synovitis can develop after a bump in activity levels. But it’s more common in kids than adults, Dr. Boyd notes. It can cause limping along with hip pain.

• Ankle synovitis. This may occur after an ankle sprain — particularly if the joint hasn’t fully regained strength or mobility. “If you’ve had a prior injury, that area may be more sensitive to changes in load,” says Dr. Boyd. 

• Shoulder synovitis. This is often linked to repetitive overhead movements — such as racquet sports, throwing, swimming, or heavy lifting. 

• Wrist synovitis. This can develop with repetitive tasks like typing or texting. It’s also sometimes seen in people with inflammatory types of arthritis (specifically, rheumatoid arthritis).

How movement can help synovitis

If your joint feels swollen or sore, you may feel reluctant about moving around. But movement is medicine: gentle exercise is one of the most effective ways to help ease synovitis discomfort.

“Movement improves joint lubrication, supports circulation, and strengthens the muscles that help support the joint,” says Dr. Boyd. It can also help reduce stiffness by encouraging fluid to move through the area.

Start with gentle, tolerable movement. As your symptoms improve, gradually rebuild toward your usual activity level. The goal isn’t to avoid movement — it’s to find your movement sweet spot: the level of activity that challenges your joint without significantly increasing discomfort.

Below, find PT-recommended exercises for easing synovitis in commonly affected areas of the body.

Together, these movements improve joint mobility, strengthen supporting muscles, and encourage healthy circulation to the affected joint. As your joint becomes stronger, swelling and stiffness typically improve. Start gently, stay consistent, and build gradually toward your usual activity level.

The information contained in these videos is intended to be used for educational purposes only and does not constitute medical advice or treatment for any specific condition. Hinge Health is not your healthcare provider and is not responsible for any injury sustained or exacerbated by your use of or participation in these exercises. Please consult with your healthcare provider with any questions you may have about your medical condition or treatment.

Treatments for synovitis

“Regular movement is the ‘secret sauce’ for treating synovitis,” says Dr. Boyd. Simple treatments like targeted exercises, movement modifications, and cold and heat therapy can all help you feel better. 

Consider trying these strategies:  

• Try physical therapy and targeted exercises. Targeted exercises, like the ones above, can help increase mobility and range of motion in the joints affected by synovitis. You can do exercise therapy at home or work with a physical therapist who can guide you through movements tailored to your needs. You can see a physical therapist in person or use a program like Hinge Health, where you may access a PT via telehealth/video visit.

• Stay active. Targeted exercises are designed to help with recovery, but any type of movement — like walking, stretching, or even household chores — can improve synovitis. Stick to low-impact and mobility-based movements to start, Dr. Boyd says. 

• Pace your activities. Modify activities that trigger pain. If standing or walking for long periods aggravates symptoms, break up activity into shorter sessions. “If your pain is really intense, listen to your body — pushing through pain isn’t the answer, but some discomfort is okay,” says Dr. Boyd.

• Apply heat or ice. Ice can help reduce inflammation and decrease swelling. Taking a warm bath or applying a heating pad directly to the affected joint can boost blood flow to and ease tension from surrounding muscles, ligaments, and tendons. Try both methods, or stick to the one that works best for you. 

• Take over-the-counter (OTC) medication. Pain relievers such as ibuprofen (Advil, Motrin), naproxen (Aleve), and acetaminophen (Tylenol) can help ease pain so you can do your targeted exercises and stay active when you have joint pain from synovitis. Other options are topical NSAIDs or pain relief creams. If you have a medical condition or take other medications, check in with your provider to make sure these OTC options are ‌safe to take.

• Consider lifestyle modifications. Factors like sleep, stress, nutrition, and certain activities can all play a role in how you feel. In fact, many people are surprised to learn that pain isn’t just about what’s happening physically — your daily habits and overall well-being can have a real impact, too. Staying curious about how your routines affect your muscles and joints can help you identify where small changes might help reduce pain. For example, you might notice your pain is less noticeable on low-stress days.

• Address underlying conditions. If your synovitis is connected to another health condition — such as osteoarthritis, inflammatory arthritis, or Lyme disease — working with your healthcare provider to manage that condition can help reduce joint flares. Treating the root cause can make it easier to calm inflammation and support long-term joint health.

• Consider complementary treatments. Talk to your provider if you’re interested in trying alternative treatments for synovitis relief, such as massage, acupuncture, dry needling, or chiropractic care.

• Ask about TENS therapy. TENS, or transcutaneous electrical nerve stimulation, uses gentle pulses to quiet your pain response and help reduce pain from synovitis. One option is the wearable device Enso, available through Hinge Health. It’s small, wireless, and portable.

How to prevent synovitis

While you can’t always prevent a synovitis flare, there are things you can do to reduce the likelihood of experiencing one. These approaches include:

• Build up slowly. “If you’re starting a new activity, or ramping up one, do it gradually so you don’t push your body past your movement sweet spot,” advises Dr. Boyd. While it’s safe to exercise with synovitis, you may need to temporarily dial back on intensity to prevent even more discomfort and promote healing. 

• Eat a healthy diet. Eating a plant-based diet rich in fruits, vegetables, and healthy fats found in foods like avocado, olive oil, fatty fish, and nuts will tamp down inflammation in your body that can contribute to synovitis.

• Stay hydrated. Water helps to create synovial fluid around your joints, which can help prevent stiffness and subsequent discomfort, says Dr. Boyd. 

• Strengthen supporting muscles. Strong muscles help your joints better tolerate stress and changes in activity. When the muscles around a joint are conditioned and working well together, they help distribute load more evenly and reduce irritation to the synovial lining. Incorporating regular strengthening exercises into your routine can improve joint resilience over time. You can work with a physical therapist to help establish a consistent strength training plan.

When to see a doctor

Synovitis often improves with exercise therapy and other at-home treatments. But if your symptoms are severe, getting worse, or causing difficulty with daily activities, see a healthcare provider, says Dr. Boyd. It's also a good idea to get care if you have:

• Pain and swelling that continue to worsen after a few days

• Increasing warmth or redness around the joint

• Fever

• Difficulty bearing weight on the affected joint

• Sudden symptoms affecting multiple joints

How long does synovitis take to heal?

Recovery time depends on what’s driving your synovitis. If it’s related to overuse, injury, or a temporary spike in activity, many people notice significant improvement within four to eight weeks of activity modification and targeted exercise, says Dr. Boyd.

If synovitis is linked to a chronic condition like osteoarthritis or inflammatory arthritis, symptoms may take longer to settle and can flare from time to time. With the right combination of gentle aerobic movement, strengthening exercises, and medical management when needed, most people are able to keep symptoms manageable and stay active.

PT tip: Take your workout to the pool

“If land-based exercise feels uncomfortable, try moving in water,” says Dr. Boyd. “The buoyancy of water reduces stress on your joints while still allowing you to build strength and mobility.” It’s a great way to stay active as your joint calms down.

How Hinge Health can help you

If you have joint or muscle pain that makes it hard to move, you can get the relief you’ve been looking for with Hinge Health’s online exercise therapy program.

The best part: You don’t have to leave your home because our program is digital. That means you can easily get the care you need through our app when and where it works for you.

Through our program, you’ll have access to therapeutic exercises and stretches for your condition. Additionally, you’ll have a personal care team to guide, support, and tailor our program to you.

See if you qualify for Hinge Health and confirm free coverage through your employer or benefit plan here.

This article and its contents are provided for educational and informational purposes only and do not constitute medical advice or professional services specific to you or your medical condition.

References

1. Arvikar, S. L., & Steere, A. C. (2022). Lyme Arthritis. Infectious Disease Clinics of North America, 36(3), 563–577. doi:10.1016/j.idc.2022.03.006

2. Cao, Q., & Li, Y. (2025). Signal Transduction Pathways Involved in Acupuncture-Mediated Inhibition of Synovitis in Knee Osteoarthritis: A Comprehensive Review. International Journal of General Medicine, Volume 18, 4105–4117. doi:10.2147/ijgm.s528486

3. Shmerling, R. H., & Miloslavsky, E. M. (2025, November 18). Evaluation of polyarticular joint pain (polyarthralgia) in adults. Uptodate.com. https://www.uptodate.com/contents/evaluation-of-polyarticular-joint-pain-polyarthralgia-in-adults

4. Whitelaw, C. C., & Varacallo, M. A. (2024, March). Transient Synovitis. Nih.gov; StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK459181/#article-30477

5. Jiang, T., Weng, Q., Liu, K., He, H., Zhang, Y., Zhang, W., Doherty, M., Xie, J., Yang, T., Li, J., Yang, Z., Chen, Q., Long, H., Wang, Y., Wei, J., Lei, G., & Zeng, C. (2024). Bidirectional association identified between synovitis and knee and hand osteoarthritis: A general population-based study. The Lancet Regional Health - Western Pacific, 50, 101169. doi:10.1016/j.lanwpc.2024.101169