Professional and Linguistic Assessments Board (PLAB) Practice Exam

What is the most appropriate investigation for suspected osteomyelitis?

1. X-ray

2. CT scan

3. MRI

4. Bone scan

The correct answer is: MRI

The most appropriate investigation for suspected osteomyelitis is MRI. This imaging technique provides detailed visualization of both bone and soft tissue structures, making it particularly effective for detecting inflammation, infection, and marrow changes associated with osteomyelitis. MRI can identify the presence of osteomyelitis earlier than other imaging modalities, as it shows not just the bone involvement but also related soft tissue changes, such as abscess formation or edema. In the context of investigating osteomyelitis, while X-rays can reveal bone changes over time, they may not show early disease manifestations and can miss subtle signs. CT scans are useful for evaluating complex areas of the body and may show bone details but are less sensitive compared to MRI for soft tissue abnormalities. A bone scan, while helpful in detecting metabolic activity in the bones and can indicate areas of infection, it lacks the specificity of MRI for confirming osteomyelitis, as it can also show increased uptake in various other conditions. Therefore, MRI is the most suitable choice for providing a comprehensive view needed for diagnosing osteomyelitis.