Plica Syndrome

What Causes Plica Syndrome?

Plica syndrome occurs when the medial plica in your knee becomes inflamed and irritated. This irritation can be caused by repetitive overuse or trauma to the knee. It can also occur due to incorrect alignment or movement of the patella, which can cause the plica to rub against the bone.

What is Plica Syndrome?

Plica syndrome occurs when the plica in your knee becomes inflamed. The plica is a fold of synovial membrane located in the anteromedial aspect of the knee. It is present in about 50% of the population and is a remnant of embryonic connective tissue that did not fully resorb during fetal development. While your knee may have four plicae, the medial plica is most likely to be symptomatic.

What are the Symptoms of Plica Syndrome?

If you have plica syndrome, the inflamed plica in your knee may catch during repetitive knee straightening and bending, blunt trauma or knee twisting, fat pad irritation, altered knee motion, or internal knee derangements such as meniscal tears. This can result in persistent knee pain and weakness in the quadriceps muscles. Plica syndrome often occurs concurrently with other knee conditions, such as meniscal injuries, patellar tendinopathy, and Osgood-Schlatter’s Disease.

Common symptoms of plica syndrome include pain and discomfort in your knee, which may worsen with activities such as running or climbing stairs. You may also experience a clicking or popping sensation in your knee. To diagnose plica syndrome, your doctor may check for anteromedial knee joint line pain, visible and palpably tender plica, or an audible clicking or snap during knee motion, which is painful between 30 to 60 degrees (Dupont, 1997). Additionally, a positive duvet test, where the pain is eased by using a duvet between your knees to ease the pain in bed, may also indicate plica syndrome. Activities such as ascending and descending stairs, squatting, rising from a chair, or sitting for extended periods can also cause pain (Shetty et al., 2007). Quadriceps atrophy is common in chronic cases.

How is Plica Syndrome Diagnosed?

Your physiotherapist or sports doctor can diagnose plica syndrome through a clinical examination. However, it is essential to have your knee thoroughly assessed to rule out other knee pathologies, particularly meniscal injuries.

While an X-ray may be helpful in ruling out associated pathologies, it will not identify a plica. MRIs can detect plica inflammation but are more helpful in diagnosing other pathologies related to plica irritation. Thus, a comprehensive examination by your physiotherapist or sports physician is preferable for accurate diagnosis.

Plica Syndrome Treatment

The treatment for plica syndrome involves reducing inflammation and pain through rest, ice, compression, and elevation. Physiotherapy can help correct any alignment or movement issues contributing to the condition. In severe cases, surgery may be required to remove the affected plica.

Research indicates that around 60% of patients with plica syndrome will recover successfully with conservative physiotherapy treatment within 6 to 8 weeks. The physiotherapy treatment aims to reduce pain and inflammation, improve patellofemoral alignment, normalise muscle lengths, strengthen the knee and lower limb muscles, address foot biomechanics issues, improve proprioception, agility and balance, and enhance lower limb function and quality of movement.

After a thorough examination, it is essential to discuss your knee injury with a knee clinician such as a physiotherapist, sports physician or knee surgeon. This approach can minimise the chances of re-aggravating your plica syndrome.

Plica Surgery

Consider undergoing arthroscopic knee surgery to treat plica syndrome that persists beyond 3 to 6 months. The surgery involves performing a lateral retinaculum release to allow the patella to track more medially, which can alleviate plica irritation as it rolls over the medial femoral condyle. The surgery has a success rate exceeding 85%. (Gerbino et al. 2007).

How to Prevent Plica Syndrome?

It is essential to take proactive measures to manage knee injuries. This includes maintaining normal knee joint alignment, adequate strength and flexibility in the muscles around the knee joint and the rest of the lower limb, wearing appropriate footwear that supports foot biomechanics, and considering weight management as a long-term preventative measure to reduce pressure on lower limb joints.

Patients with plica irritation may try using a knee brace to alleviate pain. An effective patellofemoral brace can be a helpful alternative to kneecap taping.