Introduction
Cartilage has many functions, including the ability to resist compressive forces, enhance bone resilience, and provide support on bony areas where there is a need for flexibility. The primary cell that makes cartilage is the chondrocyte, which resides within the lacunae. The matrix of cartilage consists of fibrous tissue and various combinations of proteoglycans and glycosaminoglycans. Cartilage, once synthesized, lacks lymphatic or blood supply and the movement of waste and nutrition is chiefly via diffusion to and from adjacent tissues. Cartilage, like bone, is surrounded by a perichondrium-like fibrous membrane. This layer is not efficient at regenerating cartilage. Hence, its recovery is slow after injury. The lack of active blood flow is the major reason any injury to cartilage takes a long time to heal. Cartilage has no nerve innervation, and hence there is no sensation when it is injured or damaged. When there is calcification of cartilage, the chondrocytes die. This is followed by the replacement of cartilage with bone-like tissue. Unlike bone, cartilage does not have calcium in the matrix. Instead, it contains high amounts of chondroitin, which is the material that provides elasticity and flexibility.