Working out the cause. Nail varnish is one of the most common causes. After painting your nails, the varnish will give off tiny amounts of chemical vapour for a while, even when it feels dry. If you rub your eye, the eyelid skin may react. Artificial nails can cause a similar eyelid reaction.
The PCL (posterior cruciate ligament) is the strongest ligament, or band of tissue, in your knee. It stretches across the back of your knee. It connects your shinbone to your thigh bone and keeps your knee stable. A sharp, violent blow to the knee can stretch or tear your PCL. That can make it hard for you to get around.
This is more common with an injury to the ACL. After a PCL injury, people often think they only have a minor knee problem. They may try to go on with their usual activities. However, symptoms that can develop include: 1  Swelling (mild to severe). 2  Knee pain. 3  Wobbly sensation in the knee.