Osteosclerosis, an elevation in bone density, is normally detected on an X-ray

X-ray

X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...

 as an area of whiteness, and is where the bone density has significantly increased. Localized osteosclerosis can be caused by injuries that compress the bone, by osteoarthritis

Osteoarthritis

Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...

, and osteoma

Osteoma

An osteoma is a new piece of bone usually growing on another piece of bone, typically the skull. It is a benign tumor.When the bone tumor grows on other bone it is known as "homoplastic osteoma"; when it grows on other tissue it is called "heteroplastic osteoma".Osteoma represents the most common...

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It is associated with:

• Melorheostosis
  Melorheostosis
  Melorheostosis is a medical developmental disorder and mesenchymal dysplasia in which the bony cortex widens and becomes hyperdense in a sclerotomal distribution.-Diagnosis:...
  
  
• Osteopetrosis
  Osteopetrosis
  Osteopetrosis, literally "stone bone", also known as marble bone disease and Albers-Schonberg disease is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis, in which the bones become less dense and more brittle,...
  
  
• Osteopoikilosis
  Osteopoikilosis
  Osteopoikilosis is an benign, autosomal dominant sclerosing dysplasia of bone characterized by the presence of numerous bone islands in the skeleton....
  
  
• Chronic idiopathic myelofibrosis

It can also be associated with Hepatitis C

Hepatitis C

Hepatitis C is an infectious disease primarily affecting the liver, caused by the hepatitis C virus . The infection is often asymptomatic, but chronic infection can lead to scarring of the liver and ultimately to cirrhosis, which is generally apparent after many years...

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Osteosclerotic bones provide ballast

Ballast

-Objects:* Ballast tank, a device used on ships and submarines and other submersibles to control buoyancy and stability* Ballast weights, metallic plates used to bring auto racing vehicles up to the minimum mandated weight...

 to aquatic air-breathers

Cetacea

The order Cetacea includes the marine mammals commonly known as whales, dolphins, and porpoises. Cetus is Latin and is used in biological names to mean "whale"; its original meaning, "large sea animal", was more general. It comes from Ancient Greek , meaning "whale" or "any huge fish or sea...

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