Ruth,
The UK DO situation is sort of a mess. The long story is that AT Still went to England to start up ostetopathy in England too way back in the day. A Scottish doctor came over also and was one of the first graduated DO's.
In the US, osteopathy became far more comprehensive in nature. In the UK, it stayed true to/never escaped from (depending on who you talk to) its original goal of manipulation and only manipulation.
So the UK is full of "osteopaths" who practice manipulative medicine, but who do not and are not permitted to practice a full scope of medicine. Therefore, the UK and most of the Commonwealth has never allowed US DO's to practice anything beyond manipulation.
You probably know more about this than I do, but I think Canada's only recently allowed DO's full practice rights. They're still forbidden in New Zealand, Ireland, Scot/Wal/Eng, etc. It's a shame, since so many DO's are primary care, which is what the UK needs desperately. I know that if the restrictions were lifted, I'd be over there in a flash, and I'm sure many others feel the same way.