Osteomyelitis

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Osteomyelitis, term applied to any inflammation of bone or bone marrow, usually caused by infection by such microorganisms as Staphylococcus aureus, various streptococci, Mycobacterium tuberculosis, and a host of others, as well as several fungi. The microorganisms generally reach the bone through the bloodstream from infection elsewhere. Occasionally osteomyelitis occurs by direct infection after surgery, after a compound fracture, or as a result of trauma.

Osteomyelitis, especially bacterial, may occur as an acute disease. Common symptoms include chills followed by fever, with acute pain and swelling above the site of inflammation. The inflammation begins in the marrow cavity and causes softening and erosion of the long bones, often with the formation of pus-containing abscesses, and soon spreads over the entire bone, with consequent death of the hard portions of the bone.

Chronic osteomyelitis, as is often seen in tuberculosis, fungus infections, or in patients with bacterial infections from other organisms, tends to run a slower and less dramatic course, with less severe pain and less fever, often resulting in bone destruction.

Acute osteomyelitis is treated by injections of antibiotics such as nafcillin, and by concurrent surgery to open the affected bone and drain the pus and dead tissue. Because of antibiotics, severe acute osteomyelitis is rare.

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