Plica Syndrome
Plica Syndrome is a condition where a small fold of tissue from the lining of the knee joint (synovial lining) called a plica, becomes irritated or inflamed. This tissue is normally soft and flexible, but when it gets irritated, it can cause pain, swelling, clicking, or a catching feeling in the knee. The pain usually happens in the front or inner side of the knee and may get worse with activity. Plica Syndrome is more common in young adults and athletes, especially those who do a lot of repetitive knee movements like running, biking, or squatting.
How and When Does Plica Syndrome Happen?
Everyone is born with plicae in the knee, but they usually shrink and do not problems as we grow. Sometimes, though, the plica remains thick or becomes inflamed due to overuse, injury, or repeated motion. This can happen slowly over time, especially with sports or activities that involve a lot of bending and straightening of the knee. Plica Syndrome can also occur after a knee injury, such as a direct hit to the kneecap or a twist. In these cases, the plica gets irritated and starts to rub against other parts of the knee, causing pain.
How Is Plica Syndrome Diagnosed?
A doctor will start by asking about your symptoms and checking how your knee moves during a physical exam. They might press on different parts of your knee to find the tender spot. Plica Syndrome can be tricky to diagnose because its symptoms are similar to other knee problems like patellofemoral pain or meniscus tears. X-rays usually look normal with Plica Syndrome, so doctors may use MRI scans to rule out other issues. Sometimes, the plica can’t be clearly seen on an MRI, and the diagnosis is made based on symptoms and how the knee responds to treatment.
Treatment of Plica Syndrome
Most of the time, Plica Syndrome can be treated without surgery. Doctors usually start with rest, ice, anti-inflammatory medications (like ibuprofen), and physical therapy. Stretching and strengthening the muscles around the knee can help relieve pressure on the plica. You may also be advised to avoid activities that cause pain, like squatting or running on hard surfaces. A knee brace or sleeve might be used to reduce irritation during activity. These treatments often help reduce inflammation and allow the plica to settle down.
When Is Surgery Needed for Plica Syndrome?
If non-surgical treatments does not help after several months, surgery may be considered. Surgery is usually only needed if the plica stays painful and causes problems with movement. The operation is called an arthroscopic plica excision. In this minimally invasive surgery, the doctor uses a small camera and tiny tools inserted through small cuts in the knee to remove or trim the inflamed plica tissue. This helps stop it from rubbing or catching inside the knee joint.
Long-Term Outlook for Plica Syndrome
The outlook for people with Plica Syndrome is usually very good. Most people recover well with simple treatments like rest and therapy. If surgery is needed, recovery is generally quick, and most people are able to return to their normal activities within a few weeks. Physical therapy after surgery helps restore strength and motion in the knee. It’s important to follow the rehab plan to prevent the problem from coming back.
Summary
Plica Syndrome is a condition where a fold of tissue in the knee becomes irritated, often from overuse or injury. It causes pain and a catching or clicking feeling in the front or inside of the knee. Doctors usually diagnose it with a physical exam and sometimes imaging like an MRI. Most cases get better with rest, therapy, and medication. If pain continues, surgery to remove the plica may be needed. With the right treatment, most people recover fully and return to their regular activities.
Edited by Amari Eubanks and Stephen Pinney MD, August 18th 2025.