Chrupavka

Chrupavka, the Czech term for cartilage, is a firm, flexible connective tissue that forms a key component of the skeletal system and other structures. Cartilage is characterized by a dense extracellular matrix produced by chondrocytes and by being avascular and aneural in many regions.

Cartilage exists in three main forms: hyaline cartilage (most common; covers joint surfaces and forms the embryonic skeleton), elastic cartilage (provides flexible support in the ear and epiglottis), and fibrocartilage (tough, found in intervertebral discs, menisci, and the pubic symphysis). The perichondrium, a fibrous layer containing blood vessels, surrounds most cartilage except for articular cartilage.

Chondrocytes reside in lacunae within the matrix. The extracellular matrix consists largely of type II collagen and aggrecan, with water making up a large fraction of total weight, giving cartilage its resistance to compression.

Growth and repair: cartilage grows by appositional growth (new chondrocytes added at the surface) and interstitial growth (within the tissue). Because it is avascular, cartilage has limited regenerative capacity; nutrients diffuse from the perichondrium or surrounding tissues, and injuries heal slowly. In joints, articular cartilage lacks perichondrium and is especially limited in healing.

Clinical relevance: cartilage damage is central to osteoarthritis and chondral injuries; treatments include microfracture, autologous chondrocyte implantation, and tissue-engineered grafts. Cartilage pathology is diagnosed by imaging and, when needed, histology.