In the adult Rule of Nines, what percentage is assigned to the groin?

• A. 9%
• B. 18%
• C. 1%
• D. 4.5%

Answer: (C)

The main concept is the Rule of Nines, used to quickly estimate burn size in adults by assigning whole-body percentages to major regions. The groin area is a small region and is counted separately as 1% of total body surface area (the perineum). So, in the adult distribution, the groin accounts for 1%, while the other large regions add up to the remaining 99% (head and neck 9%, each arm 9%, trunk anterior 18% and posterior 18%, each leg 18%).