Yes my mare had one in her fetlock. It was removed under GA through keyhole surgery. Could hardly tell where the Surgeon had gone in to do the op. Full recovery made.
She was lame and the bone chip was found when she had an xray. The lameness in the end had nothing to do with the chip, it was due to the tear in her DDFT within her hoof and was found via MRI scan. Cost - not sure but it wasnt horrendous, all came under the Insurance claim. Think it was all under £1500 or so.
I Had a Deer - Hound Lurcher Pup with OCD about 20 years ago the Vet operated and the Dog was then sound all its life and they still have the flake they removed in Sugical spirit to show trainee vets thankfully I had bought the Dog from the Vets Wife so only got charged about £100