What is the involucrum?

What is the involucrum?

Definition of involucrum : a surrounding envelope or sheath.

What is involucrum sequestrum?

A sequestrum is a segment of necrotic bone that becomes separated or “sequestered” from the healthy intact bone. The reactive bone that forms around the necrotic sequestrum is referred to as the involucrum and the draining tract extending from the skin to the sequestrum is termed the cloaca.

Why involucrum is formed?

Involucrum formation typically indicates chronic osteomyelitis that the body is walling off and isolating from the immune system. This means that surgical debridement, particularly of a sequestrum if present, is typically required for cure, though the thickened outer layer of involucrum may not itself need debrided 1.

What is cloaca in bone?

cloacae or cloacas) is a gap in the cortex of a bone affected by chronic osteomyelitis that allows the drainage of pus or other material from the bone into the adjacent tissues.

What animals have involucrum?

To use the lingo, the presence of the involucrum is a synapomorphy of the whales; a unique feature that whales inherited from their ancestor. Indohyus, like all the whales and in contrast to all other artiodactyls, has an involucrum.

Do whales have an involucrum?

The inner edges of these bulbs are so thick and dense that they get their own name – the involucrum. It’s not just modern whales that display this structure. An involucrum is a very, very ancient cetacean trait.

What is sequestration of bone?

A bony sequestrum (pl. sequestra) is a piece of devascularised bone that becomes separated from the remainder of the bone in chronic osteomyelitis and acts as a nidus for ongoing infection 1.

Why whales are like Kutchicetus?

Like other early whales, Kutchicetus lived in tropical seas. Its fossils are found in sediment that formed in shallow seas sheltered by barrier islands. How did Kutchicetus swim? Its hind legs are smaller than those of earlier whales and probably had little to do with propulsion.

Why Codman triangle is formed?

Codman triangle (previously referred to as Codman’s triangle) is the triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone. A Codman triangle is not actually a full triangle.

When is sequestrectomy done?

A sequestrectomy is a surgical procedure involving the removal of a sequestrum—a fragment of dead bone or other tissue that has separated from healthy tissue as a result of injury or disease. Such fragments (the plural form is sequestra) often end up in a wound or abscess (a collection of pus).

Can a human be born with a cloaca?

Persistent cloaca is rare, occurring in one in every 20,000 to 50,000 live births. The congenital defect only occurs in infants with female reproductive systems. Once the defect is identified, the next step is to determine which systems are involved and the severity of the malformation.

What is a cloacal kiss?

Life 11 June 2008. SOME male birds possess a wiggling tongue-like knob on their genitals, probably to titillate their mates. In typical bird copulation, males and females momentarily press together their cloacas – genital openings – in what biologists call a cloacal kiss.

What is a Kutchicetus?

Kutchicetus is an extinct genus of early whale of the family Remingtonocetidae that lived during Early-Middle Eocene (Lutetian and Ypresian) in what is now the coastal border of Pakistan and India (23.7°N 68.7°E, paleocoordinates6.0°N 61.8°E).

What did the Kutchicetus look like?

Kutchicetus minimus was a small otter-like species that lived in the early to middle Eocene between 43 and 46 million years ago. They belong to the Remingtonicetidae family, characterized by long snouts and long, powerful tails. Fossils have been excavated from the coastal border of Pakistan and India.

What is the difference between involucrum and cloaca?

The reactive bone that forms around the necrotic sequestrum is referred to as the involucrum and the draining tract extending from the skin to the sequestrum is termed the cloaca. Sequestrum formation should be suspected in nonhealing wounds or wounds that reopen and drain following closure.

What is the function of cloaca in birds?

July 4, 2017. A cloaca is an orifice through which urine and feces are eliminated in birds, reptiles, amphibians, and a few branches of the mammal family tree. It also serves a reproductive function like the vagina in females of these species, and also performs the function of sperm ejaculation in males of some species.

What is an involucrum?

An involucrum (plural involucra) is a layer of new bone growth outside existing bone. In pyogenic osteomyelitis where it is a layer of living bone that has formed about dead bone. It can be identified by radiographically (i.e., with x-rays ). In cetaceans such as whales, it is a thick covering of bone over the middle-ear space.

What is the cloaca in the human body?

A cloaca is a common chamber into which some or all of the digestive, urinary, and reproductive tracts discharge their contents. A cloaca exists in all human embryos up to 4–6 weeks, at which time it becomes partitioned into the urogenital sinus and the rectum.