Under normal circumstances bone is protected against infection from the outside by skin and soft tissues. However, certain risk factors may lead to an infection taking hold.
Factors which lead to the development of osteomyelitis include diseases with reduce immune status such as diabetes and malnutrition, and 'local factors' including open fractures, surgical trauma, pressure sores and poor circulation.
There are two main types of osteomyelitis:
Acute osteomyelitis is where the bone infection develops within two weeks of an initial infection, injury or underlying disease and may respond to antibiotic treatment. Acute osteomyelitis can usually be treated using antibiotics.
These medicines are usually given as a six-week course, and for part of the treatment course they may need to be taken intravenously (directly into a vein). During this time, you may need to stay in hospital, but if you are well enough you may be able to receive the injections as an outpatient. Generally you are able to switch to tablets for the rest of the treatment course.
Chronic osteomyelitis is where the bone infection has produced changes of the bone that cannot be treated by antibiotics alone. This usually requires a combination of antibiotic medication and surgery to remove the damaged bone.
A surgeon may need to make an incision (cut) near the site of the infection to drain away any pus. If there is extensive bone damage, it will be necessary to surgically remove any diseased bone and tissue. This procedure is known as debridement. Debridement can often leave an empty/'dead' space in the bone, which can act as a focus point for more infection and so needs to be filled.
This can be done using a synthetic bone graft substitute such as CERAMENT®|G or CERAMENT® V, in what is called a 'single-stage' procedure. This is because they deliver a high local dose of antibiotic and remodel into bone at the same time, with the newly formed bone providing the best protection against the infection coming back/recurring.
Traditionally, filling dead space in the bone has been done as two-stage surgeries; with a bone cement spacer or beads loaded with antibiotics being placed in the void, and 8-12 weeks later when the infection has gone, a second surgery is carried out to remove the spacer or beads, as they cannot remodel into bone, and can become a focus point for future infection.
In some cases, in addition to filling the void, it may also be necessary to transfer muscle and/or skin (called a skin graft or skin flap) from another part of the body to repair the skin and tissue surrounding the affected bone.
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Cierny G & Mader JT. The surgical treatment of adult osteomyelitis. In: Evarts CM, et al., eds. Surgery of the musculoskeletal system. Vol. 4. New York: Churchill Livingstone, 1983:10:15-35.