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.
The MCL is located on the inner side of the knee and the LCL is located on the outer side and these two ligaments work to control the side to side stability of the knee joint. When the MCL or LCL is injured, it can result in a sprain, partial tear or full tear, depending on the severity. What causes a MCL/LCL Sprain/Tear? MCL and LCL sprains and tears occur most often from direct impact to the side of the knee, often as a result of contact sports. MCL injuries occur from an impact to the outer side of the knee, while LCL injuries are more likely from a trauma to the inner side of the knee.