Osteosclerosis

From ArticleWorld

Osteosclerosis is a condition of several etiologies that involves the development of deposits of excessively dense bone with surrounding areas of less dense or much weaker bone.

Etiology

The condition of osteosclerosis has several synonyms. It is also known as osteopetrosis, osteosclerosis fragilis and Albers-Schoenberg disease. An individual can have this disorder as a congenital defect. The bony X-rays show clusters of very white, dense bone where cancellous bone, which is much less dense, should be.

Osteosclerosis can also be found in humans or animals exposed to a great degree of fluoride. Excessive fluoride replaces the normal hydroxyl groups of calcium hydroxyapatite, the mineral component of bone into an inorganic fluoride substance called calcium fluorapatite. This kind of bony substance is more brittle and does not receive the same nutrients as normal organic bone.

Areas of osteosclerosis can occur in any part of the bone that has received a strong compression injury. Some compression fractures can lead to osteosclerosis. Osteoarthritis can cause areas of compact bone. Localized benign bone tumors, called osteomas, can become the source of a small area of osteosclerosis.

Consequences

Osteosclerosis can be identified only on X-ray and can be completely asymptomatic. If a part of osteoarthritis or a compression injury to bone, there can be bony pain. Osteosclerosis that is either generalized, as with fluoride toxicity, or in a weight bearing bone, can result in a brittle bone that is prone to fracture.

Even though osteosclerotic bone is denser than normal bone, it has none of the flexibility of normal bone so that a pathological or spontaneous fracture of bone at the site of the sclerotic bone. Bone that has been replaced by an inorganic substance receives no nutrition and is quite brittle, leading to the occurrence of a fracture at the site of the brittle area.