Before diagnosing osteomyelitis, a specialist doctor performs a physical examination and may then request various tests to confirm the diagnosis. These tests may include:

* Complete Blood Count (CBC): Performed to assess signs of inflammation or infection in the body, particularly an increase in white blood cell count.
* Imaging Tests: Magnetic Resonance (MR), Computed Tomography (CT), and ultrasound provide detailed images of bones, muscles, and surrounding tissues, showing the extent and effects of the infection.
* Bone Scintigraphy (Bone Scan): Used to identify areas of increased metabolic activity in bones, such as those indicating infection, inflammation, or fractures.
* Biopsy: The specialist doctor may take samples from the affected area (fluid, tissue, or bone) via needle biopsy to determine the type and cause of the infection.