American Board of Internal Medicine (ABIM) Certification Practice Exam

What is considered the best imaging technique for diagnosing osteomyelitis?

1. X-ray

2. MRI

3. CT scan

4. Bone scan

The correct answer is: MRI

MRI is considered the best imaging technique for diagnosing osteomyelitis due to its high sensitivity and specificity in detecting bone marrow edema, which is often associated with infection. MRI can visualize changes in bone and surrounding soft tissues, allowing for the identification of both acute and chronic osteomyelitis. It excels in differentiating between osteomyelitis and other conditions such as bone tumors or fractures, providing comprehensive information about the extent of the infection and any involvement of adjacent structures. In contrast, X-rays are often the first imaging modality used but have limitations, particularly in early stages of osteomyelitis, as they might not show changes until a few weeks after the onset of the infection. CT scans can be useful in certain situations, especially for visualizing complex anatomy or in cases of chronic osteomyelitis, but they are not as sensitive as MRI for detecting soft tissue changes and bone marrow involvement. Bone scans can indicate increased metabolic activity in bone but are less specific and cannot confirm the diagnosis of osteomyelitis without correlating clinical findings. Therefore, MRI’s detailed imaging capabilities make it the preferred method for accurately diagnosing osteomyelitis.