Cartilage is a connective tissue that plays a major role in the human body. It is a lubricant, provides support to body tissues and generally maintains the structure of the body notes News Medical.
Structure of Cartilage The human body forms cartilage from a threadlike network of collagen fibers. The thread-like network or matrix is generated by body cells known as chondroblasts. Once the chondroblast matrix forms, it will house cartilage cells known as chondrocytes. The chondrocytes help in regeneration of new cartilage to replace or repair damaged cartilage.
Cartilage can exist as one connective tissue or as a cluster of connective tissues in a space called lacuna. These connective tissues do not contain blood vessels or nerves. Therefore, they rely on a membrane known as the perichondrium, which has blood vessels, to supply nourishment to the connective fibers.
Types of Cartilage Cartilage exists in three main forms within the body: fibrocartilage, elastic cartilage and hyaline cartilage. The three cartilage forms differ in terms of structure, location in the body and core function.
Fibrocartilage Fibrocartilage is the toughest connective tissue of the three. It contains several chondrocytes dispersed within dense matrices of collagen fiber. The density of the fibrocartilage matrices make them easy to be seen by the naked eye. Fibrocartilage does not have a perichondrium for blood vessel support.
In the human body, fibrocartilage is located in areas where strong support of connective tissues is required. This includes the tendons that hold cartilage tissues to joints. Fibrocartilage also makes the major part of the vertebrae spine where support for the intervertebral discs is required.
Fibrocartilage plays a vital role where skeletal bones join or overlap. The tough connective tissues are present in menisci pads, which are the padding found on knee joints. Fibrocartilage exists in the pubic symphysis joint, which is the area where the front hipbones connect. These tough collagen tissues also exist in the callus, a tough tissue that forms over fractured or healing bones. Fibrocartilage provides support for the backbone and joints.
Hyaline Cartilage Hyaline makes up most of the three cartilage forms in the body. Hyaline cartilage exists as a network of collagen fibers held together by what is called a chondroitin matrix. This matrix contains traces of sulphates that give it its characteristic blue-white color. Moreover, hyaline contains significant amounts of chondrocytes, which explains its abundance.
Hyaline cartilage is present in costal cartilages, bronchial tubes, trachea and the larynx or voice box. Hyaline cartilage is also present on the anterior ends of the rib cage and over the surface of bone joints. In addition, this type of cartilage plays an important role in the formation of embryonic skeleton in a fetus.
Given its smooth and soft nature, this type of cartilage plays a role in lubricating joints and facilitating joint movement. Hyaline cartilage provides flexibility for muscle tissues in the human body.
Elastic Cartilage As the name suggests, elastic cartilage is a flexible tissue. These yellowish tissues exist in a matrix of collagen fibers and contain perichondrium for nourishment. Elastic cartilage is abundant in areas where flexibility is required including the epiglottis covering the larynx, the external ear or auricle and the Eustachian tubes that act as auditory channels.