Anatomy - joint is not a muscle

I never say the joint its a muscle?

You cannot do a thing on the joint, I think you can put a needle injection in the joints, for the pain relief !! I wonder if there is a service like that before the knee replacement !!!!

You know one of those police job's, why they getting more fat on their belly or the school, or the elementary, or anything like that....

The kids growing up has some kinds of the anger management over their principle's abdomen, or those overweight a bit police man carried the belly those belts stuffs carried-on.

You know what I mean?