A Synovial plica is a fold of the synovial membrane in the knee joint. It has similar symptoms to patellofemoral pain. As a result, it is often misdiagnosed or missed.
Medically reviewed by Dr Chaminda Goonetilleke, 21st Dec. 2021
Symptoms
Symptoms of a synovial plica include:
- Sharp pain at the front inside edge of the kneecap
- Pain may also be towards the back of the patella
- You may feel a sharp pain when squatting
It sometimes feels like a thickened band of tissue under the inside of the kneecap. However, your physio or doctor might only consider this as the main cause of your pain only when you fail to respond to Patellofemoral pain treatment.
What is a Synovial plica?
A Synovial plica is a fold in the synovial membrane on the inside border of the kneecap.

Synovial fluid lubricates the knee joint. The synovial membrane (synovial sheath) produces and contains the fluid within the joint. The synovial sheath may also be inflamed. This is called knee synovitis.
Treatment for a Synovial plica
Treatment involves reducing pain and inflammation. However, you may need surgery to identify and remove the fold in the synovial membrane.
Cold therapy
Apply ice or cold therapy for 15 minutes every three hours. initially to reduce pain, swelling, and inflammation. Reduce frequency as your symptoms improve.
Do not apply ice directly to the skin as it may burn. Wrap the ice in a wet tea towel or better still use a specialist cold compression wrap.
Rest
Rest is important for the injury to heal.
Medication
A doctor may prescribe NSAID or anti-inflammatory medication, for example, Ibuprofen for pain relief and to help decrease swelling.
Surgery
A surgeon may perform an arthroscopy to look into the joint, identify a plica and remove it.