What are the preferred sites for DXA scans in children?

• A. The femur and total body
• B. Lumbar spine and total body minus the head
• C. Wrist and lumbar spine
• D. Pelvis and total body

Answer: (B)

In children, the preferred sites for DXA scans are the lumbar spine and total body minus the head. This choice is correct because these areas are typically representative of bone density in pediatric populations and can provide valuable information about overall skeletal health.

The lumbar spine is commonly assessed due to its significant role in weight-bearing and its susceptibility to osteoporosis, which can differentiate children with low bone mass. The total body measurement minus the head is important as it includes a comprehensive look at bone density while avoiding variations in skull bone density that can occur due to differing head sizes and shapes in children.

These sites are chosen because they reflect skeletal maturity and are less affected by factors such as body habitus, which may complicate interpretations in varying ages of children. Additionally, the lumbar spine provides an area that allows for good reliability in measurements due to its soft tissue composition and established reference values.

In contrast, other anatomical sites listed are either not preferentially selected due to concerns about anatomical variations or do not provide as comprehensive a picture of bone health in pediatric patients. For instance, scanning the femur or pelvis may be less common in evaluating bone density in children compared to the selected sites.