Which Rule of Nines component is correctly matched?

• A. Head 9%
• B. Arms 9%
• C. Genitals 1%
• D. Posterior torso 18%

Answer: (C)

Rule of Nines is a quick way to estimate burn surface area by assigning fixed percentages to body regions in adults. The genital region is a small, distinct area that represents about 1% of total body surface area, so stating Genitals 1% matches the rule exactly. In the same framework, the head is 9%, each arm is 9%, the trunk is split into anterior 18% and posterior 18%, and each leg is 18%. These estimates are used for rapid assessment and fluid resuscitation planning. For children, proportions differ, and the Lund and Browder chart is often used for greater accuracy.