Malacia is abnormal softening of a
biological tissue
In biology, tissue is a biological organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are ...
, most often
cartilage
Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck an ...
. The word is derived from Greek μαλακός, ''malakos'' = soft. Usually the
combining form
Neoclassical compounds are compound words composed from combining forms (which act as affixes or stems) derived from classical Latin or ancient Greek roots. New Latin comprises many such words and is a substantial component of the technical an ...
-malacia suffixed to another combining form that denotes the affected tissue assigns a more specific name to each such disorder, as follows:
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Osteomalacia
Osteomalacia is a disease characterized by the softening of the bones caused by impaired bone metabolism primarily due to inadequate levels of available phosphate, calcium, and vitamin D, or because of resorption of calcium. The impairment of bone ...
(rickets), a bone disorder from vitamin D deficiency
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Chondromalacia
Chondromalacia patellae (also known as CMP) is an inflammation of the underside of the patella and softening of the cartilage.
The cartilage under the kneecap is a natural shock absorber, and overuse, injury, and many other factors can cause in ...
, softening of cartilage (often refers to chondromalacia patellae when mentioned without further specification)
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Chondromalacia patellae
Chondromalacia patellae (also known as CMP) is an inflammation of the underside of the patella and softening of the cartilage.
The cartilage under the kneecap is a natural shock absorber, and overuse, injury, and many other factors can cause inc ...
, a disorder of cartilage under the kneecap
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Bronchomalacia
Bronchomalacia is a term for weak cartilage in the walls of the bronchial tubes, often occurring in children under a day. Bronchomalacia means 'floppiness' of some part of the bronchi. Patients present with noisy breathing and/or wheezing. There is ...
, a disorder of the bronchial tubes' cartilage
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Laryngomalacia
Laryngomalacia (literally, "soft larynx") is the most common cause of chronic stridor in infancy, in which the soft, immature cartilage of the upper larynx collapses inward during inhalation, causing airway obstruction. It can also be seen in olde ...
, a disorder of the larynx's cartilage
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Tracheomalacia
Tracheomalacia is a condition or incident where the cartilage that keeps the airway (trachea) open is soft such that the trachea partly collapses especially during increased airflow. This condition is most commonly seen in infants and young child ...
, a disorder of the trachea's cartilage
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Keratomalacia, an eye disorder from vitamin A deficiency
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Myelomalacia
Myelomalacia is a pathological term referring to the softening of the spinal cord. Possible causes of myelomalacia include cervical myelopathy, hemorrhagic infarction, or acute injury, such as that caused by intervertebral disc extrusion.
In adva ...
, a disorder of the spinal cord
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Cerebral softening
Cerebral softening, also known as encephalomalacia, is a localized softening of the substance of the brain, due to bleeding or inflammation. Three varieties, distinguished by their color and representing different stages of the disease progress, a ...
(encephalomalacia), localized softening of brain tissue
External links
Definition at MedineNet.com
Medical terminology
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