An 8-year-old boy has a painful limp and medial knee pain. What is the appropriate initial management step?

In this scenario, where an 8-year-old boy presents with a painful limp and medial knee pain, the initial management step involves obtaining diagnostic imaging and laboratory tests to help evaluate the underlying cause of his symptoms.

Ordering a hip x-ray, a complete blood count (CBC), and an erythrocyte sedimentation rate (ESR) is appropriate because it allows for the assessment of both structural issues in the hip joint, which can sometimes manifest as knee pain, and potential signs of inflammatory or infectious processes that could be present in this age group. The hip x-ray will help rule out conditions such as Perthes disease or other hip pathologies that can lead to referred pain in the knee.

The CBC can help identify anemia or signs of infection, while the ESR is a marker of inflammation that might indicate an underlying systemic condition or infection. This combination of imaging and lab tests provides a comprehensive initial assessment that can guide further management.

This step is essential before considering referrals or more invasive procedures, ensuring that the clinical picture is fully understood based on empirical data.