Final answer:
Ullman's Line is a radiological marker used to diagnose hip dysplasia, where a positive result indicates the femoral head lies medial to the line, suggesting hip dysplasia.
Step-by-step explanation:
Ullman's Line is a radiological landmark used primarily in the diagnosis of hip dysplasia in pediatric cases. In a radiological evaluation, Ullman's Line is drawn on an anteroposterior (front to back) pelvis radiograph. It is drawn tangentially to the upward slope of the superior margin of the triradiate cartilage, continuing across the pelvis. The significance of Ullman's Line as a landmark is that it helps in assessing the position of the femoral head in relation to the acetabulum.
A positive result regarding Ullman's Line in a radiological evaluation indicates that the femoral head lies medial to this line and is therefore considered to be in a position suggestive of hip dysplasia. If the femoral head lies lateral to Ullman's Line, it is deemed to be in a normal position relative to the acetabulum. In the context of diagnosing hip disorders, this line can be an important indicator of possible developmental issues that may require intervention.