National Physical Therapy Examination (NPTE) Practice Exam

What percentage of total body surface area is affected if a patient has suffered burns to the anterior portions of bilateral lower extremities?

1. 40%

2. 36%

3. 9%

4. 18%

The correct answer is: 18%

When assessing burn injuries using the Rule of Nines, each major body area is assigned a percentage of total body surface area (TBSA). For adults, the anterior aspect of each lower extremity accounts for 18% of the TBSA. Since the question specifies burns to the anterior portions of bilateral lower extremities, you need to consider both legs. Calculating the total for both anterior lower extremities involves adding the 18% from one leg to the 18% from the other leg, resulting in a total of 36%. However, since the question specifically asks for the anterior portions only, the individual contribution of each leg is considered separately as 9% (4.5% for each anterior lower extremity). Thus, if you were to only consider the anterior parts, the percentage would be 18%, accounting for both legs collectively. Therefore, the correct answer is that the anterior portions of both lower extremities together account for 36% of TBSA, which is reflected in the provided answer option. This emphasizes the importance of comprehensively understanding the proportions used to assess burn areas in both clinical practice and theoretical questions, which aligns with guidelines for volume resuscitation and potential complications based on TBSA.