Synovectomy is surgery to remove part or all of the synovium, a layer of connective tissue that lines the inside of your joints. The synovium releases fluid and nutrients to keep your joints healthy and moving smoothly.
When you have rheumatoid arthritis (RA) or another type of inflammatory arthritis, your synovium can get swollen and painful. This inflammation is called synovitis. An inflamed synovium makes too much fluid, which wears away the cartilage that cushions your joint. Without cartilage, the bones around the joint rub painfully against each other.
Taking out the inflamed tissue doesn’t cure RA. But it can slow cartilage damage and improve joint pain, at least for a while.
Who Gets This Surgery?
Synovectomy treats inflammatory arthritis such as RA, psoriatic arthritis, and juvenile idiopathic arthritis. (It’s also used to treat joint damage resulting from the blood clotting disorder hemophilia.)
You may need this surgery if other treatments don’t help your pain and other arthritis symptoms. Treatment for inflammatory arthritis usually starts with a disease-modifying antirheumatic drug (DMARD) and possibly steroid injections. If you take a DMARD for at least 6 months, but your joint pain and other symptoms don’t improve, your rheumatologist might refer you to an orthopedic surgeon to discuss synovectomy.
Your surgeon will make sure you're a good candidate before recommending synovectomy. They may use imaging technologies like X-rays, MRI, or CT scan to evaluate your bones and joints.
Synovectomy only helps if you have some cartilage left in your joint. If RA has worn away most or all of the cartilage, your doctor might suggest a different treatment.
Most people have synovectomy on a knee, but doctors also do this surgery on the:
What Happens During a Synovectomy?
Surgeons do synovectomy in one of two ways: arthroscopy or open surgery. For both types, you need medicine to numb the area (local anesthesia), numb the lower part of your body (regional anesthesia), or put you in a sleep state so you don’t feel pain (general anesthesia).
Arthroscopy is a type of surgery with just a few small incisions. For knee surgery, doctors will put a tourniquet on the area to limit blood flow. They’ll also stretch the area using a pressure irrigation system.
Through the small incisions, your surgeon will insert tiny instruments and a miniature camera called an arthroscope into the joint. The camera projects pictures onto a screen so the surgeon can see inside your joint while removing the synovium.
Most synovectomies are now done using this method. It’s less expensive, requires less healing time, and complications are less likely than with open surgery. However, it takes longer and is difficult to do on certain joints.
Open surgery is when a surgeon makes a larger incision over your joint. Through this opening, they cut out and remove part or all of the synovium.
Radiation synovectomy is a less invasive procedure. The doctor injects a radioactive substance into the joint, which causes the synovium to break down. It’s considered experimental, and isn’t available everywhere.
Chemical synovectomy uses strong drugs, injected into the joint, to break down the synovium. It’s also not widely available.
What Can You Expect After Surgery?
You might feel some discomfort after a synovectomy. Ask your doctor about pain relief options. Resting, icing the joint, and raising it can reduce pain and swelling.
You’ll want to get the joint moving as soon as possible to regain strength and flexibility. If your joint hurts too much to put weight on it after surgery, you might use a continuous passive motion (CPM) machine to move the joint for you.
If you had a synovectomy on your knee, you’ll need to wear a cast after your operation. You may need to use crutches to keep weight off the knee while it heals.
A day or two after surgery, you'll start to work with a physical therapist. The therapist will teach you exercises to help you regain the range of motion in your joint. Do only as much exercise as your doctor or therapist recommends. Putting too much weight or pressure on the joint could affect healing.
Healing should take a few weeks. Recovery from arthroscopy is faster than from open surgery. Arthroscopy also causes less pain and blood loss, but it’s a more complex procedure that requires a very skilled surgeon.
What Is the Success Rate for Synovectomy?
The success rate for this surgery varies depending on your condition and which type of procedure you have. Synovectomy improves joint pain for a time, but it doesn't help as much with movement. Some people actually lose the ability to move their joint because scar tissue forms.
Even if you have a good result, it might not last. The synovium often grows back a few years after surgery. Synovitis is more likely to come back after an arthroscopic procedure than open surgery. If it returns, your doctor will let you know whether you need a repeat procedure.
One study looked at the effectiveness of synovectomy in people with RA of the knee. Around a third of people who had the surgery still had moderate or serious pain afterward. Those without serious knee damage before surgery showed the best results. Researchers noted that surgery didn’t completely stop the disease.
If you have RA or PsA, you’ll still need to take a DMARD after surgery. Staying on the medicine will help prevent your synovium from inflaming again and protect your other joints from damage.
What Are the Possible Complications?
In addition to the possibility of scar tissue that can limit your movement, synovectomy can cause the same kinds of problems as other types of surgeries. They include:
- Blood clots
- Tissue damage
- Nerve damage
Arthroscopic synovectomy tends to cause less pain, blood loss, and other problems than open surgery.
Call your doctor if you have any of these symptoms:
- Intense pain that medication doesn’t relieve
- Redness or swelling
- Drainage from the surgical area
- Numbness or tingling
Before you have a synovectomy, ask your surgeon what to expect. Learn about the pros, cons, and healing time. And find out if there are any other options to this procedure that you might consider.