Table of Contents
It can be sub-classified based on the:
- organism that caused the infection
- the route of the infection
- duration
- anatomic location of the infection
In rare circumstances bone and joint infections can even be fatal, but luckily, an early diagnosis and proper treatment can help control or eliminate the infection.
Incidence
The incidence of osteomyelitis is 2 in 10,000 people. Neonatal prevalence is approximately 1 per 1,000. The annual incidence in sickle cell patients is approximately 0.36%. The prevalence of osteomyelitis after foot puncture may be as high as 16%. 30-40% of all patients are diabetics. Male-to-female ratio is approximately 2:1.
The route of infection
Several researches done in the past have proven that bacteria can infect the bones in a number of ways. The most common bacterium that causes osteomyelitis is Staphylococcus aureus.
- It can travel into the bone through the bloodstream from other infected areas in the body. This is called Hematogenous osteomyelitis. Studies are indicating that this the most common way people get bone infections.
- Direct infection is also common. It happens when bacteria enter the body's tissues through a wound and travel to the bone. This mostly happens following an injury or trauma. Open fractures are the injuries that most often cause osteomyelitis.
- When the blood supply to that area of the bone is disrupted, it can also result in bone infection. This can happen in older people with atherosclerosis and sometimes it is also associated with diabetes. Most infections of this kind occur in toes or feet.
Possible causes of osteomyelitis
Beside the Staphylococcus aureus, Escherichia coli and streptococci are other common pathogens. In some subpopulations, including intravenous drug users, Gram negative bacteria, including enteric bacilli, are also a significant pathogen. In osteomyelitis involving the vertebral bodies, 50 percent of the cases are due to Staphylococcus aureus, and the other 50 percent due to tuberculosis.
Tubercular osteomyelitis of the spine was very common before the initiation of effective anti-tubercular therapy.
The infection that causes osteomyelitis often has a root in another part of the body and spreads to the bone via blood. Affected bone may have been predisposed to infection because of some recent trauma.
When we talk about children’s osteomyelitis, usually the long bones are affected, while, in adults, it is the vertebrae and the pelvis. When the bone is infected, pus is produced within the bone, which may result in an abscess. The abscess then deprives the bone of its blood supply causing bone tissue to die and leading to chronic osteomyelitis which can persist intermittently for years.