What's the matter with the dog's front foot suddenly sticking out?

O-leg caused by calcium deficiency. Treatment: 1. Usually stop feeding homemade food to dogs and switch to high-quality special dog food. And feed a cooked pig's hind leg bone every day. 2. Add 2~3 vitamin AD pills, 5 vitamin B complex tablets and 3~5 calcium tablets to the soaked dog food. Generally, dogs with calcium deficiency will recover in about 15 days after diet and drug treatment.