What Is Your Knee Plica?
A plica is a fold of synovial membrane most commonly in the anteromedial aspect of the knee. A knee plica is present in about 50% of the population and is the remnants of embryonic connective tissue that failed to resorb during your foetal development fully. Luckily, most plicae are asymptomatic.
While your knee potentially has four plicae, it is the medial plica that is most likely to be symptomatic (Dupont 1997). It runs parallel to your medial patella just below your medial retinaculum and inserts into your fat pad.
What is Plica Syndrome?
Plica syndrome is essentially an inflamed plica. Your plica can catch during:
- repetitive knee straightening and bending,
- blunt trauma or knee twisting,
- fat pad irritation,
- altered knee motion,
- internal knee derangements, e.g. meniscal tears. (Schindler 2004)
Consider plica syndrome if you experience persistent knee pain and weakness in the quadriceps muscles. Plica syndrome often does not always occur in isolation, but concurrently with other knee conditions such as meniscal injuries, patellar tendonitis and Osgood-Schlatter’s Disease.
What are the Symptoms of Plica Syndrome?
Plica syndrome can be suspected when you have:
- Anteromedial knee joint line pain; especially medial femoral condyle.
- Visible and palpably tender plica.
- Audible clicking or snap during knee motion – painful arc 30 to 60 degrees. (Dupont 1997).
- Positive Duvet test: pain eased by using a duvet between your knees to ease the pain in bed.
- Pain with activities: ascending and descending stairs, squatting, rising from a chair or sitting for extended periods. (Shetty et al. 2007).
- Quadriceps atrophy is common in chronic cases.
How is Plica Syndrome Diagnosed?
Your physiotherapist will be able to diagnose plica syndrome clinically. It is more vital that you have your knee thoroughly assessed by a physiotherapist or sports doctor to exclude other knee pathologies, in particular, meniscal injuries.
An x-ray may be useful to rule out other associated pathologies but will not identify a plica. MRIs can detect plica inflammation. However, MRI is more helpful in diagnosing other pathologies that may be related to the plica irritation. A comprehensive examination by your physiotherapist or sports physician is preferable.
Plica Syndrome Treatment
Studies show that about 60% of patients with plica syndrome will settle successfully with conservative physiotherapy treatment within 6 to 8 weeks. (Lu et al. 2010).
Your physiotherapy treatment will aim to:
- Reduce pain and inflammation.
- Improve patellofemoral (knee cap) alignment via taping, bracing and exercises.
- Normalise your muscle lengths.
- Strengthen your knee: esp quadriceps (esp VMO) starting with closed-chain exercises and eventually progressing to open-chain exercises
- Strengthen your hip and lower limb muscles.
- Address foot biomechanics issues.
- Improve your proprioception, agility and balance.
- Improve your lower limb function and quality of movement, e.g. walking, running, squatting, hopping and landing.
- Minimise your chance of re-aggravating your plica syndrome. (Gerbino et al. 2007).
We strongly suggest that you discuss your knee injury after a thorough examination by a knee clinician such as a sports physiotherapist, sports physician or knee surgeon.
Should your symptoms persist beyond 3 to 6 months, consider arthroscopic knee surgery for a plica syndrome. The most successful surgery involves lateral retinaculum release to allow the patella to track more medially and thereby alleviate plica irritation as it rolls over the medial femoral condyle. Success rates exceed 85%. (Gerbino et al. 2007).
How to Prevent Plica Syndrome?
Since plica syndrome usually occurs concomitantly with other knee conditions, it is essential to be proactive in managing your other knee injuries. This proactivity involves maintaining normal knee joint alignment, adequate strength and flexibility in the muscles around the knee joint plus the rest of the lower limb. It is ensuring that you wear appropriate footwear that supports your foot biomechanics. Also, weight-management can play a role in the pressure exerted on lower limb joints, and thus should be something considered as a long-term preventative measure.
Braces for Plica Irritation
Many patients will try a knee brace. A brace that improves patellofemoral joint alignment seems to be the most effective to ease the plica-related pain.
An effective patellofemoral brace can be useful as an alternative to kneecap taping.
Common Causes - Knee Pain
Knee pain can have many origins from local injury, referred pain, biomechanical issues and systemic issues. While knee pain can appear simple to the untrained eye, a thorough assessment is often required to ascertain the origin of your symptoms. The good news is that once a definitive diagnosis is determined, most knee pain quickly resolves with the correct treatment and rehabilitation.
Knee Ligament Injuries
- Knee Ligament Injuries
- ACL Injury
- PCL Injury
- MCL Sprain
- LCL Sprain
- Posterolateral Corner Injury
- Superior Tibiofibular Joint Sprain
Knee Meniscus Injuries
- Chondromalacia Patella
- Fat Pad Syndrome
- Patella Dislocation
- Patellofemoral Pain Syndrome
- Osgood Schlatter’s Disease
- Sinding Larsen Johansson Syndrome
Knee Tendon Injuries
- Corked Thigh
- Thigh Muscle Strain
- Hamstring Strain
- ITB Syndrome
- Popliteus Syndrome
- Muscle Strain (Muscle Pain)
- DOMS – Delayed Onset Muscle Soreness
Children’s Knee Conditions
Other Knee-Related Conditions
- Runner’s Knee
- Plica Syndrome
- Stress Fracture
- Overuse Injuries
- Restless Legs Syndrome
For specific information regarding your knee pain, please seek the assistance of a healthcare professional with a particular interest in knee condition, such as your physiotherapist.