A bone fracture  (abbreviated FRX or Fx, Fx, or #) is a medical condition in which there is a partial or complete break in the continuity of a bone. In more severe cases, the bone may be broken into several fragments, known as a comminuted fracture. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta, where the fracture is then properly termed a pathologic fracture. Signs and symptoms
Although bone tissue contains no pain receptors, a bone fracture is painful for several reasons:
Breaking in the continuity of the periosteum, with or without similar discontinuity in endosteum, as both contain multiple pain receptors. Edema and hematoma of nearby soft tissues caused by ruptured bone marrow evokes pressure pain. Involuntary muscle spasms trying to hold bone fragments in place.Damage to adjacent structures such as nerves, muscles or blood vessels, spinal cord, and nerve roots (for spine fractures), or cranial contents (for skull fractures) may cause other specific signs and symptoms. Complications
Some fractures may lead to serious complications including a condition known as compartment syndrome. If not treated, eventually, compartment syndrome may require amputation of the affected limb. Other complications may include non-union, where the fractured bone fails to heal or mal-union, where the fractured bone heals in a deformed manner.
The trait is now extinct and was never fully characterized.Diplopodia-3
This is an autosomal trait that may be the least severe of the five. Diplopodia-4
This sex-linked mutation is similar to the previous mutations, but causes the embryo to grow thicker wing bones.Diplopodia-5
This is an autosomal mutation that gives embryos webbing between the inner two front toes on each foot, in addition to the usual characteristics of diplopodia. Almost all of the embryos survive to the end of incubation, but they are unable to clear the fluid from their lungs or absorb the blood from their extraembryonic vessels. These problems always prevent them from hatching. Almost all diplopodia-5 embryos have only one or two extra toes on each foot, so this mutation causes the least extreme foot malformation. See also
Limb development
Congenital abnormality
Dysmelia
Sonic hedgehog
Polydactyly


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