Casts & broken bones

I am writing a young adult historical novel and need to know how a
broken arm was set in the United State in 1851: Were casts used or just

Also, if an arm was pinned behind someone's back and jerked upward,
where would it be broken?

If you can answer these questions, or direct me to a URL where I can
search for the information myself, I will be extremely grateful.

Thanks for your help,
Georgia Mullen