What is osteomyelitis?

Osteomyelitis is an inflammation or swelling of bone tissue. It’s most often caused by an infection. A bone infection may occur for many reasons. It can affect children or adults.

What causes osteomyelitis?

Osteomyelitis can be caused by a bacterial infection of the blood. This is sometimes called bacteremia or sepsis. This infection can spread to the bone. It’s most common in babies and children. It often affects their long bones, such as the thighbone or upper arm bone. In adults, it often affects the bones in the spine. The source of the blood infection is usually Staphylococcus aureus. But it may be caused by other germs.

Other causes include:

• An injury or surgery

• Frequent medicine injections

• Diabetes

• A weak immune system (such as from having HIV or getting cancer treatment)

• A prosthetic device

Osteomyelitis can have a sudden start, a slow and mild start, or may be a long-term (chronic) problem. This depends on the source and cause of the infection.

Who is at risk for osteomyelitis?

Osteomyelitis can affect anyone. But it's more common in babies, children, and older adults. People at greater risk include those with a weak immune system, recent injury or surgery, or diabetes.

What are the symptoms of osteomyelitis?

Symptoms of osteomyelitis vary, depending on what is causing it and whether it starts quickly or slowly. These are the most common:

• A new limp

• A stiff back, if the spine is affected

• Feeling ill

• Fever (high fever with blood infection)

• Irritability

• Lethargy or severe tiredness (fatigue)

• Weight loss

• Pain and tenderness in the affected area

• Redness in the affected area

• Swelling of the affected area

• Trouble bearing weight or walking

• Trouble moving joints near the affected area

• Warmth in the affected area

The symptoms of osteomyelitis may look like other medical conditions or problems. Always talk with your healthcare provider for a diagnosis.

How is osteomyelitis diagnosed?

Your healthcare provider will review your medical history and give you a physical exam. You may have tests. These may include:

• Blood tests, such as:

  • Complete blood count (CBC).  This test measures the size, number, and maturity of blood cells. It’s done to check for increased white blood cells that may signal an infection.

  • Erythrocyte sedimentation rate (ESR).  This test measures how quickly red blood cells fall to the bottom of a test tube. When swelling and inflammation are present, the blood’s proteins clump together and become heavier than normal. They fall and settle faster at the bottom of the test tube. The faster the blood cells fall, the more severe the inflammation.

  • C-reactive protein (CRP).  This blood test helps find inflammation or an infection.

  • Blood culture. This blood test looks for bacteria or other germs in the blood.

• Needle aspiration or bone biopsy.  A small needle is inserted into the affected area to take a tissue biopsy.

• X-ray. This test uses invisible electromagnetic energy beams to make images of tissues, bones, and organs onto film.

• Radionuclide bone scans.  Pictures or X-rays are taken of the bone after a dye is injected and absorbed by the bone tissue. These are used to find tumors, infections, and bone abnormalities.

• CT scan. This test uses X-rays and a computer to make images (often called slices) of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.

• MRI. This test uses large magnets, radiofrequencies, and a computer to make detailed images of organs and structures in the body.

• Ultrasound. This test uses high frequency sound waves and a computer to make images of blood vessels, tissues, and organs. Ultrasounds are used to view organs as they work and to check blood flow through blood vessels.

How is osteomyelitis treated?

Treatment will depend on your symptoms, age, and general health. It will also depend on how bad the condition is.

The goal for treatment of osteomyelitis is to cure the infection and reduce any long-term problems. Treatment may include:

• Medicines. You may be given IV (intravenous) antibiotics. This often means a hospital stay. Or you may be given antibiotics as an outpatient. In either case, treatment may last for many weeks.

• X-rays and blood tests. Your healthcare provider will keep track of your test results.

• Pain management. You will get medicine to manage your pain.

• Bed rest.  You may need to limit movement of the affected area.

• Surgery. In some cases, surgery may be needed to drain fluid. Or to remove damaged tissue and bone.

What are possible complications of osteomyelitis?

Osteomyelitis needs long-term care to prevent complications, such as:

• Breaks (fractures) of the affected bone

• Stunted growth in children if the infection has involved the growth plate

• Tissue death (gangrene) in the affected area

Key points about osteomyelitis

• Osteomyelitis is an inflammation or swelling of bone tissue. It’s most often the result of an infection.

• It can affect all people, but it is more common in infants, children, and older adults.

• Causes of osteomyelitis include having a bacterial infection in the blood, an injury or surgery, frequent medicine injections, diabetes or a weak immune system, and a prosthetic device.

• The goal for treatment is to cure the infection and reduce any long-term complications.

• Long-term care is needed to prevent complications.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.

• Before your visit, write down questions you want answered.

• Bring someone with you to help you ask questions and remember what your healthcare provider tells you.

• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your healthcare provider gives you.

• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.

• Ask if your condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if you do not take the medicine or have the test or procedure.

• If you have a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your healthcare provider if you have questions, especially after office hours or on weekends.