I ripped cartlidge in my wrist.the dr. didn't want me working for four weeks at least when I called my boss to let them know he told me flat out that he will tell workman comp adjuster he has something I can do without using my left arm.insurance adjuster faxed to my dr. that my boss said I just have to stand there and tell people what to do so he released me.while at work my boss didn't like my ability and wrote notes about not working hard enough.he also told me if I wanted a medical leave he will give me one but I will not collect workmans comp. or unemployment.now my wrist is worse and dr. gave me off again.can my boss get away with this?he will probably soon have me back at work again

You can appeal whatever he says I do believe. Since you have the dr backing you up I would say your boss may be trying to intimidate you.
I think since it is the same injury and all that you should pursue it and see where it goes.

The company and the doctor can talk to the workers comp company rep. (Adjuster as you called them)

But yes if a company has "light duty work" they can require you work doing that. You can appeal doing it, but you will have to prove that the new job effects your injury.

My old company used to make people just come in and court paper clips