Tests and diagnosis
Your doctor may order a combination of tests and procedures to diagnose osteomyelitis and to determine which germ is causing the infection.
Blood tests
Blood tests may reveal elevated levels of white blood cells and other factors that may indicate that your body is fighting an infection. If your osteomyelitis was caused by an infection in the blood, tests may reveal what germs are to blame. No blood test exists that tells your doctor whether you do or do not have osteomyelitis. However, blood tests do give clues that your doctor uses to decide what further tests and procedures you may need.
Imaging tests
X-rays. X-rays can reveal damage to your bone. However, damage may not be visible until osteomyelitis has been present for several weeks. More detailed imaging tests may be necessary if your osteomyelitis has developed more recently.
Computerized tomography (CT) scan. A CT scan combines X-ray images taken from many different angles, creating detailed cross-sectional views of a person's internal structures.
Magnetic resonance imaging (MRI). Using radio waves and a strong magnetic field, MRIs can produce exceptionally detailed images of bones and the soft tissues that surround them.
Bone biopsy
A bone biopsy is the gold standard for diagnosing osteomyelitis, because it can also reveal what particular type of germ has infected your bone. Knowing the type of germ allows your doctor to choose an antibiotic that works particularly well for that type of infection. An open biopsy requires anesthesia and surgery to access the bone. In some situations, a surgeon inserts a long needle through your skin and into your bone to take a biopsy. This procedure requires local anesthetics to numb the area where the needle is inserted. X-ray or other imaging scans may be used for guidance.