Supervisor hurts herself

Real Trimet supervisory reports:
I responded to bus to remove intoxicated sleeper from the bus as he appeared to be without a destination.  Operator had been unable to arouse  him.  Initially he failed to respond to me attempts to wake him up.  After several attempts I nudged his foot with my foot and he came up screaming at me.  He was in my face and very threatening.  I immediately called for police assistance and ordered him off the bus.  He spat at my feet in an attempt to intimidate me.  After several requests to deboard he did so.  As he was walking away from the bus, he crawled into my vehicle in an attempt to steal something from the car.  I commanded him to exit the car but was unclear if he had retrieved anything.  I followed him at a distance of 1 1/2 blocks opposite side of street to maintain his location for police.  Police responded but were unable to locate him.

As I was leaving the garage and heading home, I felt extreme pain and stiffness in my right knee.  I apparently twisted it as I deboarded bus.  Injury reported 9/7 to