I know its really nerve racking but honestly you will feel so much better once you've done it. TLC, it would be much better to give them the whole drumstick because the meat sort of lubricates the bone and makes it much easier and safer for them to eat. Think about it like this, if they are just eating the bone then they have to swallow all that dry bone by itself which is hard and rough on their throats but if its with the meat then once they have crunched the bone they can pull pieces off and it and consume the meat and bone together. Its also much easier for them to digest the meat and the bone together.
Heres some good websites-
www.rawdogranch.com www.njboxers.com/faqs.htm www.naturalpetcare.co.uk/nutrition/dogdiet.htm