Medial patellar retinaculum

Looks like

A fibrous sheet on the inner side of the kneecap, joining it to the inner thigh bone and shinbone.

What it does

Stops the kneecap slipping outward.

Keeping it well

Torn when the kneecap dislocates; repeated dislocations may need surgery.

Related conditions

• ACL & meniscus injury
• Baker's (popliteal) cyst
• Chronic venous insufficiency
• Growing pains
• Juvenile idiopathic arthritis
• Lymphatic filariasis (elephantiasis)
• Lymphoedema
• Pseudogout (calcium pyrophosphate disease)
• Reactive arthritis
• Restless legs syndrome
• Septic arthritis
• Varicose veins