What are you feeding?
Did you notice the legs/feet like that when they arrived?
The toes especially look gnarled to me - I don't think I've ever seen that.
@Eggcessive may know.
If you have had this before with the same source, then I would wonder if it's a genetic defect or parent stock deficiency. Have you contacted the hatchery to see if they have seen this before?
I would get them on some poultry vitamins that contain B2. Personally I would give them Poultry Cell this has a good spectrum of vitamins, that I think may be beneficial to your chicks.