ANSWER
The radiograph shows a lucency within the lateral tibial plateau and tibial metaphysis, consistent with a fracture. It is mildly depressed and slightly comminuted.
Fluid collection is also evident on the lateral view, likely reflecting a lipohemarthrosis. The patient was placed in a knee immobilizer and made non–weight-bearing. She was instructed to follow up with an orthopedist when she returned home (as she was visiting from out of town).