Microvilli (singular: microvillus) are microscopic cellular membrane protrusions that increase the surface area of cells and minimize any increase in volume, and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction. 1 Locations.
Activities such as bending the knee, kicking or running can worsen the pain. The calf muscle, or gastrocnemius, aids in propelling you forward while walking or running. A strain at the upper end of the gastrocnemius causes pain in the back of the knee that worsens with knee bending or rising to your tiptoes. The popliteus muscle helps stabilize the knee joint during movement. Injury to this muscle can be challenging to diagnose.
What is a popliteal cyst. In the hollow at the back of the knee is a bursa or small sack of fluid used to help lubricate the joint. A fairly uncommon condition is when the back of the knee joint gets swollen and causes the bursa to swell as well. Bakers cyst is a rounded swelling at the back of the knee. It is often about the size of a golf ball but can vary over time. A sensation of pressure in the back of the joint will be felt which may go down into the calf muscle.