menisc-, menisco- +
(Greek meniskos > Latin meniscus: a crescent-shaped body, a crescent-shaped structure, sickle-shaped, lunar crescent, semilunar cartilage; diminutive of mene, "moon")
meniscal
Pertaining to, or having the form of, a meniscus; such as, damage to the meniscus of the knee.
Detailed information about
meniscal-knee damage.
meniscectomy
1. The surgical excision of a meniscus, as of the knee joint.
2. Surgical removal of the meniscus of the knee.
3. The surgical excision of a semilunar cartilage of the knee.
meniscitis
An inflammation of any interarticular cartilage; specifically, of the semilunar cartilages of the knee joint.
Meniscium
Terrestrial ferns of tropical Americas.
meniscocyte
A sickle-shaped erythrocyte (a non-nucleated and agranular mature cell of vertebrate blood whose oxygen-carrying pigment, hemoglobin, is responsible for the red color of fresh blood).
meniscocytosis
Sickle cell anemia.
meniscofemoral
Of or pertaining to a meniscus of the knee joint and the femur.
meniscoid
Concavo-convex, like a meniscus.
meniscopathy
An abnormality of a meniscus.
meniscopexy
The surgical repositioning of a displaced meniscus.
meniscus (s), menisci (pl)
1. A crescent-shaped body.
2. A concavo-convex lens.
3. The curved upper surface of a nonturbulent liquid in a container that is concave if the liquid wets the container walls and convex if it does not.
4. The free surface of a liquid that is near the walls of a vessel and which is curved because of surface tension.
5. A cartilage disk that acts as a cushion between the ends of bones that meet in a joint; part of the cartilage in the knees and other joints.
6. Often used alone to refer to one of the semilunar fibrocartilaginous disks in the knee joint.
The word "meniscus" comes from the Greek and refers to a crescent-shaped structure. Today a meniscus is something that is shaped like a crescent moon or a croissant pastry.
A meniscus can be an anatomic feature; for example, the medial meniscus of the knee is a crescent-shaped cartilage pad between the two joints formed by the femur (the thigh bone) and the tibia (the shin bone). The meniscus acts as a smooth surface for the joint to move on. The medial meniscus is toward the inner (medial) side of the knee joint.
Medical terminology
Medically speaking, the "cartilage" of the knee is known as a meniscus. The meniscus is a C-shaped piece of fibrocartilage which is located at the peripheral aspect of the joint. There are two meniscii in each knee, the medial meniscus, and the lateral meniscus.
The majority of the meniscus has no blood supply. For that reason, when damaged, the meniscus is usually unable to undergo the normal healing process that occurs in most of other areas of the body. In addition, with age, the meniscus begins to deteriorate, often developing degenerative tears.
Typically, when the meniscus is damaged, the torn piece begins to move in an abnormal fashion inside the joint. Because the space between the bones of the joint is very small, as the abnormally mobile piece of meniscal tissue moves, it may become caught between the bones of the joint (femur and tibia). When this happens, the knee becomes painful, swollen, and difficult to move.
meniscus lens
1. An element in a single lens in which the curvature centers of both of its surfaces lie on the same side of the lens so that both surfaces are concave or both are convex.
2. A lens with one convex surface and one concave surface.
meniscus sign
1. A radiographic sign associated with an ulcerating carcinoma, in which the outline of the stomach is crescentic with overhanging edges.
2. A snapping or clicking associated with a torn meniscus in the knee.
polymeniscous
Having numerous facets; said of the compound eyes of insects and crustaceans.
Meniscus as observed in nature
- To a tiny insect, a pond's still surface can present a challenging waterscape.
- To move from water to land, a water-walking creature may have to scale a steep, slippery slope—the curved edge where water meets leaf, rock, or floating object.
- The curvature of a liquid's surface at a boundary is a consequence of the liquid's surface tension.
- The sloped surface marking the border between wet and dry is called the meniscus.
- Very small insects typically can't climb these frictionless mountains using their normal rowing motions or running gaits.
- If they try to walk up, they slide back down.
- Instead, these insects have to rely on a novel form of propulsion that doesn't require moving their legs back and forth.
- As this water treader approaches a meniscus, its front and rear legs deform the water's surface to help it move up the slope.
- Two species of water strider, for example, have retractable claws on their front and hind legs that allow them to pull up on the water to create tiny peaks.
- At the same time, the central pair of legs presses down on the water to form dimples in the surface.
- Because the insects are small, these peaks and dimples create sufficient force to pull the insects up the slope.
- In effect, the insect creates tiny menisci with its front and rear legs.
- Because menisci are attracted to other menisci, the net effect is to pull the insect up the slope at the water's edge.
- These creatures can reach speeds as high as thirty body lengths per second.
- In technical terms, the insects take advantage of lateral capillary forces that exist between small floating objects.
- The force of attraction between body and meniscus "wall" depends on the body's buoyancy and on its distance from the wall.
- Because the insect's front legs are closer to the wall than its rear legs are, the net effect is to propel the insect forward and upward.
- The larva of the waterlily leaf beetle uses an alternative strategy to scale a slippery meniscus.
- A poor swimmer, this creature simply arches its back, creating a meniscus at each end. The insect then gets pulled up the slope to a leaf.
- In meniscus climbing, the researchers note, instead of moving its legs back and forth, an insect deforms the liquid's surface, converting muscular strain to the surface energy that powers its ascent.
- In the realm of fluid dynamics, few researchers have previously tackled situations that involve surface tension as an important component.
- The new results and related research may have important applications not only for understanding biolocomotion but also potentially in nanotechnology.
—From the article, "Climbing a Watery Slope" by Ivars Peterson,
in Science News Online, Week of November 5, 2005;
Vol. 168, No. 19.
A cross reference of word units that are related, directly or indirectly, to the: "moon":
Calendar, Moon Facts;
Chemical Element: selenium;
Gods and Goddesses;
luna, luni-;
Luna, the earth moon;
meno-;
Planets in Motion;
plano-;
seleno-.
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