Review Question - QID 210736

A 10-year-old boy is referred to a pediatric neurologist by his pediatrician for lower extremity weakness. The boy is healthy with no past medical history, but his parents began to notice that he was having difficulty at football practice the previous day. Over the course of the past 24 hours, the boy has become increasingly clumsy and has been “tripping over himself.” On further questioning, the boy had a viral illness the previous week and was out of school for 2 days. Today, the patient’s temperature is 99.3°F (37.4°C), blood pressure is 108/72 mmHg, pulse is 88/min, respirations are 12/min. On motor exam, the patient has 5/5 strength in hip flexion, 5/5 strength in knee extension and flexion, 3/5 strength in foot dorsiflexion, and 5/5 strength in foot plantarflexion. The findings are the same bilaterally. On gait exam, the patient exhibits foot drop in both feet. Which of the following areas would the patient most likely have diminished sensation?