Our knowledge of orthopaedics. Your best health.

Infections typically occur after fractures because bacteria enter the body during the traumatic event. Although uncommon, bacteria can also enter the body during surgery to set the broken bones or later, after the injury has healed.  

Open Fractures

When a bone breaks in such a way that bone fragments stick out through the skin or a wound penetrates down to the bone, it is called an "open" or compound fracture. The skin normally acts as a barrier to outside contaminants, including bacteria. When the skin is broken, bacteria can easily travel down to the broken bone and this can lead to infection.

Illustration and x-ray show an open fracture. The broken end of the tibia (shinbone) has torn through the soft tissues and is sticking out through the skin.

(Right) Reproduced from Egol KA, Gardner MJ, eds: Let's Discuss Management of Common Fractures. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2016, pp. 135-152.

An infection after fracture will usually cause increased pain, warmth, redness, and swelling around the affected area — more than what is considered normal. In addition, a pus pocket may form and, if it bursts, pus will drain from the injury. You may also have a fever, chills, and night sweats.

(Left) This infected wound on the outside of the ankle is red and swollen. (Right) A close-up image clearly shows a moist area that appears to be draining pus.

If the infection is near a joint, such as your knee or shoulder, the joint may be painful and difficult to move.

Even if an infection appears obvious, your doctor may order an X-ray if you have not had one recently. Blood tests may also be used to help diagnose the infection. These may include:

• WBC (white blood cell count)
• ESR (sedimentation rate)
• CRP (C-reactive protein)

If these tests do not confirm the infection, your doctor may order additional tests, such as a computerized tomography (CT) scan, tagged white blood cell scan, or magnetic resonance imaging (MRI) scan, although this is rare.

If the suspected infection is near a joint, your doctor will probably use a needle to draw fluid from the joint. This fluid will then be analyzed to determine if bacteria are present.

Because a healing fracture may show the same positive test results as an infection, it is often hard for doctors to firmly diagnose an infection after a fracture. It is often up to the knowledge and experience of the doctor to determine whether there is an infection.

An open fracture is a surgical emergency.

• You will be started on antibiotics as soon as possible in the emergency room.
• Your doctor will then clean the wound and remove as much contamination as possible from the skin, soft tissues, and bone. This procedure, called debridement and irrigation, is typically performed in an operating room. It is suggested that people with open fractures undergo debridement and irrigation as soon as is reasonable, ideally within 24 hours of sustaining the injury. Depending on the severity of your injury, you may require several debridement and irrigation procedures. 

If you have an infection after surgery, your doctor may initially treat it with antibiotics alone, but you will likely need additional surgery to clean out the infection. During surgery, your doctor will either swab or take samples of the infected tissue to find out what type of bacteria is causing the infection. This stage of treatment may require more than one surgery. Special drains may be placed in the wound to help rid it of pus. Antibiotic delivery systems, like "antibiotic beads," may also be used to provide higher concentrations of antibiotics.

Antibiotic beads, like the ones shown here, can be used to help prevent or treat an infection after a fracture.

Reproduced from Zalavras CG, Marcus RE, Levin LS, Patzakis MJ: Management of open fractures and subsequent complications. Instr Course Lect 57. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2008: pp. 51-63.

Once the type of bacteria is identified, your doctor can choose the most effective antibiotics to treat the infection. An infectious disease specialist may work with your doctor to determine the appropriate antibiotics. Most patients will have to take antibiotics for 6 to 12 weeks.

A bone infection can be hard to eliminate. It may require long-term antibiotic treatment, as well as several surgeries. Occasionally, a patient may need to take antibiotics for the rest of their life.

In very rare cases, amputation of the infected limb may be considered. Amputation is usually performed only as a life-saving operation for a severe infection that is out of control.

An infection after a fracture may require multiple trips to the operating room, long-term antibiotic treatment, and a long period of healing. If an infection is successfully treated, however, almost all patients will recover without serious, ongoing problems.

To help doctors prevent and treat infections — including surgical site infections — the American Academy of Orthopaedic Surgeons has conducted research to provide some useful guidelines. These are recommendations only and may not apply to every case. For more information: Surgical Site Infections - Clinical Practice Guideline (CPG) | American Academy of Orthopaedic Surgeons (aaos.org)