A young college student injures his left knee while playing football and is unable to bear weight. The provisional x-ray report indicates that there are no fractures seen. He is discharged home but presents the next morning to the emergency department with a severely swollen, painful left knee and severe pain in the foot. On examination, the foot is pale, cold, and pulseless. What is the most likely diagnosis?
Traumatic deep vein thrombosis Gastrocnemius muscle tear Traumatic arteriovenous fistula Posterior knee dislocation with thrombosed popliteal artery