Thrown off a horse

I suppose it depends on their landing. feet first or head first.

feet first: sprain on ankles or maybe a broken leg.

head first: scraps on face, hands.

i hope that helps. i know it not much.

okay. that's clear it up a whole bunch.

if they were sliding along the ground, they are bound to have scrapes on the hands, arms and legs. oh and grass strains.

if they hit their shoulder hard, they knock it up a bit, but not enough to dislocate from the socket.

No problem. you help me, so i help you.

If they're landing on their shoulder, I would say dislocated shoulder would be the most likely. Possibly a broken collar bone as well.

They could easily break some of the bones in their hands if they landed with their hands underneath themselves. Finger bones are the most likely, in medical terms, phalanges. Ankles and wrists and knees are also very easy to sprain. And it hurts like heck. Bruises, well, that's a given. Plus, don't forget to mention the very intense adrenaline rush. I've had a near-fall from a horse, and it was very scary. Dramatic as well... although I didn't actually come all the way out of the saddle. (long story...) But yeah, sprains, dislocations, plenty of bruises, possible concussion, bruised ribs, scratches, grassburn, splinters if they landed on a stick... Plenty of oppurtunities to make your character absolutely miserable. But then, isn't that what we writers do, eh? PS: I'd say you'd most likely land face-down or on your but.
--Voxina

If they hit the ground hard enough, couldn't they have inernal bleeding?

I wouldn't put it in, because I think it's virtually impossible to survive when your organs are bleeding.

If they know how to fall and are careful they can do it without any bruises or anything. If they really don't fall right and they land on anything they can get anything from a very small cut to being put into a coma or even killed. IT just depends. Pretty much anything can be believeable depending on how she/he was thrown.

Can you become lame from falling off a horse in the wrong way?

Probably if you landed on your spine weird.