Which body parts are included when calculating the 9% total body surface area?

When calculating the total body surface area affected by burns, the "rule of nines" is a commonly used method which divides the body into sections that represent approximately 9% or multiples of 9% of the total body surface area. According to this rule, the head accounts for 9%, each arm accounts for 9%, the anterior and posterior torso together account for 36% (18% for the front and 18% for the back), and each leg accounts for 18% (9% for the front and 9% for the back).

The option stating "Head, chest, abdomen, and both arms" incorporates the head (9%), which is indeed counted in the total. It also includes both arms (each contributing 9%, totaling 18%), in addition to the chest and abdomen, which combined make up a significant part of the torso (18% for the chest and 18% for the abdomen viewed front and back).

Thus, by including these specific body parts, the calculation totals up correctly to 9% for the head, 18% for the arms, and a substantial portion for the chest and abdomen, validating that this combination is a significant evaluation in assessing burn surface area. This reinforces how the