Does my dog's knee look weird?

11y6m MN lab, 75 pounds. His hip dysplasia and arthritis. We did the xray to look for food bloat, but it looks like he's missing a chunk out of his bone? The vet didn't mention anything. Is this concerning? His vet is out until Jan 3

Hmmm the knees look a odd on this x-ray don't they?  - Although it was taken to look at the abdomen, so has not been centred on the knee and the knees were not lined up for radiographic assessment.  Indeed, one tibia may be overlapping the other knee joint, so it's not an easy picture to interpret.  We are asked not to interpret radiographs on this site - the reason being that it is your vets picture ; they have much more context than we do and are better placed to give you a useful answer specific to your dog.  They can also hold it up to the lightbox and follow the contours of each bone.  Most vets are happy to answer questions like this from interested clients so we would reccommend putting it to them.