Orthotic: A support, brace, or splint used to support, align, prevent, or correct the function of movable parts of the body. Shoe inserts are orthotics that are intended to correct an abnormal, or irregular walking pattern, by altering slightly the angles at which the foot strikes a walking or running surface.
Osteoarthritis: A type of arthritis caused by inflammation, breakdown, and eventual loss of cartilage in the joints. Also known as degenerative arthritis.
Osteochondroma: An abnormal, solitary, benign growth of bone and cartilage, typically at the end of a long bone. Osteochondromas are usually discovered in persons 15 to 25 years of age. They are typically detected when the area is injured, or when they become large. It can be a hereditary condition, in which case it may be called hereditary multiple exostoses (HMS).
Osteomyelitis: Inflammation of the bone due to infection, for example by the bacteria salmonella or staphylococcus. Osteomyelitis is sometimes a complication of surgery or injury, although infection can also reach bone tissue through the bloodstream. Both the bone and the bone marrow may be infected. Symptoms include deep pain and muscle spasms in the area of inflammation, and fever. Treatment is by bed rest, antibiotics (usually injected locally), and sometimes surgery to remove dead bone tissue.
Osteopenia: Mild thinning of the bone mass, but not as severe as osteoporosis. Osteopenia results when the formation of bone (osteoid synthesis) is not enough to offset normal bone loss (bone lysis). Osteopenia is generally considered the first step along the road to osteoporosis, a serious condition in which bone density is extremely low and bones are porous and prone to shatter. Diminished bone calcification, as seen on plain X-ray film, is referred to as osteopenia, whether or not osteoporosis is present. The diagnosis of osteopenia may also be made by a special X-ray machine for bone density testing.
Osteoporosis: Thinning of the bones with reduction in bone mass due to depletion of calcium and bone protein. Osteoporosis predisposes a person to fractures, which are often slow to heal and heal poorly. It is more common in older adults, particularly post-menopausal women; in patients on steroids; and in those who take steroidal drugs.
Osteotomy: Cutting into or through bone.