Risk factors

Your bones are normally resistant to infection, but this protection lessens as you get older. Other factors that can make your bones more vulnerable to osteomyelitis may include:

Recent injury or orthopedic surgery

A severe bone fracture or a deep puncture wound gives bacteria a route to enter your bone or nearby tissue. A deep puncture wound, such as an animal bite or a nail piercing through a shoe, can also provide a pathway for infection.

Surgery to repair broken bones or replace worn joints also can accidentally open a path for germs to enter a bone. Implanted orthopedic hardware is a risk factor for infection.

Circulation disorders

When blood vessels are damaged or blocked, your body has trouble distributing the infection-fighting cells needed to keep a small infection from growing larger. What begins as a small cut can progress to a deep ulcer that may expose deep tissue and bone to infection.

Diseases that impair blood circulation include:

• Poorly controlled diabetes
• Peripheral artery disease, often related to smoking
• Sickle cell disease

Problems requiring intravenous lines or catheters

There are a number of conditions that require the use of medical tubing to connect the outside world with your internal organs. However, this tubing can also serve as a way for germs to get into your body, increasing your risk of an infection in general, which can lead to osteomyelitis.

Examples of when this type of tubing might be used include:

• Dialysis machine tubing
• Urinary catheters
• Long-term intravenous tubing, sometimes called central lines

Conditions that impair the immune system

If your immune system is affected by a medical condition or medication, you have a greater risk of osteomyelitis. Factors that may suppress your immune system include:

• Cancer treatment
• Poorly controlled diabetes
• Needing to take corticosteroids or drugs called tumor necrosis factor inhibitors

Illicit drugs

People who inject illegal drugs are more likely to develop osteomyelitis because they may use nonsterile needles and are less likely to sterilize their skin before injections.