Puppies often slip when walking, with their hind legs outstretched and their bodies constantly shaking. What happened?

First of all, it should be due to calcium deficiency, and secondly, it may be due to muscle strain and other reasons. For example, when our dog was playing with other dogs, three legs ran away 1-2 months-_-! Later, my father thought of a trick and gave him calcium tablets and Yunnan Baiyao powder every day. After about a month, he recovered, and now he has been able to walk on four legs. This is not a serious illness. Don't be too nervous. Just like people, you need to cultivate yourself.