Final answer:
An early sign of hemarthrosis in a child with hemophilia is slight joint swelling or warmth, often with minimal pain initially. This condition is due to bleeding into joint spaces resulting from insufficient clotting factors and requires prompt treatment.
Step-by-step explanation:
When collecting data on a 5-year-old child with hemophilia, an early sign of hemarthrosis is a slight swelling or warmth of the joints, often without significant pain initially. Hemarthrosis is a bleeding into joint spaces, a common complication of hemophilia, where uncontrolled bleeding occurs due to the lack of clotting factors. In cases of hemophilia, even minor trauma can lead to bleeding into joints, typically starting with a tingling sensation, progressing to mild swelling, and eventually leading to joint damage if not treated effectively. It is critical for the management of hemophilia that any early signs of joint bleeding are identified and addressed quickly with appropriate treatments like the infusion of clotting factors to prevent further complications.