An 82-year-old woman presents to the emergency department status post fall. Imaging reveals diffuse trauma to the left humerus from midshaft to the olecranon process with shearing of the periosteum to the shame region. The orthopedic doctor suggests a follow-up in 2 weeks. In that time, the patient develops worsening pain and presents to the office. She is found to have diffuse bone necrosis in the area involved with no symptoms to the distal arm structures. What structure must have been damaged to cause this diffuse bone necrosis?
A 36-year-old man undergoes ileocecal resection for a gunshot injury. Resected ileocecal segment is sent for histological evaluation. One of the slides derived from the specimen is shown in the picture below. Which of the following statements regarding the structure marked with the red circle is correct?