Metabolic Bone Disease?

[Kurt]

The knee joints seems to be deformed/disfigured in that instead of forming a smooth angle between the femur and tibiofibula, they are kiltered up, resulting in the tibiofibula sitting directly above the femur...

Sound more like rheumatoid arthritis than metabolic bone disease, but I am not a vet so I can't say for sure. I really have no clue what the problem may be.

I also forgot to mention in my first post that I occasionally throw in an algae waffer...do these harbor a good source of calcium?

Probably not. Check the package though, it should list nutritional information.