How does cartilage survive without any blood vessels running through it?

Cartilage does not completely lack blood vessels. It has a limited number of blood vessels in its outer layers, which are called the perichondrium. This is how the outermost layers of cartilage receive oxygen and nutrients. The inner layers of cartilage, however, are avascular, meaning they do not contain any blood vessels. Despite this lack of blood vessels, cartilage is still able to survive and function thanks to the diffusion of oxygen and nutrients from the surrounding tissues and synovial fluid.