Anatomical terminology and positionsDownloads

A 17-year-old boy comes to the physician because of a 3-month history of pain in his right shoulder. He reports that he has stopped playing for his high school football team because of persistent difficulty lifting his right arm. Physical examination shows impaired active abduction of the right arm from 0 to 15 degrees. After passive abduction of the right arm to 15 degrees, the patient is able to raise his arm above his head. The dysfunctional muscle in this patient is most likely to be innervated by which of the following nerves?

A neurology resident sees a stroke patient on the wards. This 57-year-old man presented to the emergency department after sudden paralysis of his right side. He was started on tissue plasminogen activator within 4 hours, as his wife noticed the symptoms and immediately called 911. When the resident asks the patient how he is doing, he replies by saying that his apartment is on Main St. He does not seem to appropriately answer the questions being asked, but rather speaks off topic. He is able to repeat the word "fan." His consciousness is intact, and his muscle tone and reflexes are normal. Upon striking the lateral part of his sole, his big toe extends upward and the other toes fan out. Which of the following is the area most likely affected in his condition?