A 9-year-old boy presents to the clinic with his parents, who report he has been increasingly clumsy for the past two years. They note that he falls frequently while running or playing with his friends. His parents describe him as having difficulty lifting his feet, causing him to drag his toes and walk with a “steppage” gait. The patient complains of mild foot pain and fatigue after walking short distances. There is no history of trauma or recent illness. His early motor milestones were normal. His family history is significant; his father has high arches and wears custom shoes, and his paternal grandmother experienced significant difficulty walking in her later years. He has a thin build, but appears well-nourished and is in no acute distress. He has a steppage gait. He is afebrile. His blood pressure is 105/65 mmHg with a heart rate of 82 bpm and a respiratory rate of 18 breaths per minute.