Reply #10: Spoiler included!!!! Here's what happened....

[vi5]

They show a flashback clip of that Locke guy in Australia. He is sitting at a desk arguing with an outback travel guide about why they won't let him go on the trip to the outback. The tour guide finally says that because of Locke's condition they just cannot let him, since he misrepresented himself. The tour guide walks out of the room and you see Locke pull away from the desk to reveal that he is in a wheelchair.

Then they cut to the original crash scene and show him lying on the ground and realizing when he wakes up that he can walk.

It explains why when he got knocked over by the boar that he lay there staring at his feet with a worried look.