A member of our community bought a treat for his dog, a "Greenie". His vet later felt the need to perform emergency surgery because of the dog's condition.
I'm not a veterinarian.  I can't say for sure what is going on here.

By now some of you may have seen the pictures below after it got passed around as email attachments and as MMS on mobile phone units. We have put them up here not to make fun out of the whole situation but rather to raise awareness on the possible threats of this "treat" not only to pets but also for toddles who may accidentally ingest them.

These pictures were taken during that emergency procedure.
Thank dog that the pooch is now doing just fine.

FAIR WARNING

If you scroll down further, you will see actual photographs taken during surgery. This is NOT a joke.

These photos are very graphic in nature; They are large, and bloody.

These photos may be disturbing to some people.

If you scroll any more, you will see them. They are large and bloody.
DO NOT SHOW THESE TO YOUR CHILDREN.

FAIR WARNING

I don't know if this was necessary -- the vet thought so.  I don't know if the risks, if any, of using Greeines to treat your dog outweigh any benefits, if any.
I think it is a good thing that the surgeons kept the heart in a sinus rhythm
Perhaps the prudent thing to do if you have a dog that tends to gulp his/her food (or to eat quickly) and you want to give Greenies, is to use the little Greenie bits that they sell, instead of the big bone/toothbrush shape.

Good luck in your decisions.