He slipped on muddy track while mounting dozer, fell to track & hit L knee on blade rail & stomach on the track. Reported fall the next day, saying he was just sore. We sent him to dr on 1/27/10 after he complained of stomach discomfort & swelling knee. They performed x ray of knee and ct scan of stomach. set up an appt. for him to see a surgeon on 2/2/10 about stomach hernia.