Review Question - QID 217954

A 21-year-old male collegiate football player sustains a hit to the right knee and is unable to bear weight after the injury. He is found to have a large effusion and his pain is difficult to localize. His physical exam findings are listed below:

-Grade 2A lachman
-Grade 2B reverse lachman
-Negative pivot shift
-Negative reverse pivot shift
-Positive varus stress at 0°/30°
-Negative valgus stress at 0°/30°
-Positive posterior sag sign
-Negative dial test at 30°/90°

Which of the following is the most likely diagnosis based on these physical examination findings?