A 23-year-old man presents to an urgent care with pain at the distal end of his left clavicle that began the previous day after he fell onto his left shoulder while mountain biking. His pain is constant and sharp and worse when moving his left arm and shoulder. He does not have fever, vomiting, chest pain, shortness of breath, or abdominal pain, and he has no head injury, no head or neck pain, and no history of previous illnesses.
View the image taken (Figure 1) and consider what your diagnosis would be. Resolution of the case is described on the next page.