Kartilagi

Kartilagi, commonly referred to as cartilage, is a flexible, avascular connective tissue that covers the ends of bones in synovial joints and also forms other structures such as the ear and parts of the respiratory tract. The tissue is produced by chondrocytes embedded in an extracellular matrix rich in collagen (predominantly type II in many cartilages) and proteoglycans. This matrix gives cartilage its strength and ability to resist compression while remaining smooth and resilient.

There are three main types of kartilagi: hyaline cartilage, elastic cartilage, and fibrocartilage. Hyaline cartilage is the most widespread and forms the articular surfaces of joints and the growth plates in children. Elastic cartilage contains elastic fibers, providing more flexibility and is found in structures like the ear and the epiglottis. Fibrocartilage is tougher and helps absorb shocks in areas such as the intervertebral discs and the knee menisci.

Cartilage has limited capacity to repair itself, in part because it is avascular and relies on diffusion from surrounding tissues for nutrients. Chondrocytes respond slowly to injury, and damage can lead to pain and impaired joint function. Growth and maintenance of cartilage differ from bone, with chondrocytes deriving from chondroprogenitor cells and cartilage growth occurring by appositional and interstitial mechanisms. In clinical contexts, cartilage injury and degeneration are central to conditions such as osteoarthritis, and treatment options include microfracture, osteochondral grafts, autologous chondrocyte implantation, and other tissue-engineering approaches.