I'm sorry about your chick.
It looks like she's been injured. I would flush the wound really well with saline, betadine or chlorhexidine (Hibiclens). Apply triple antibiotic ointment or vetericyn spray to wound.
Silkies have a vaulted skull, so she might be suffering from severe head trauma - this can cause the inability to stand/falling. If you have Poultry Nutri-Drench, give her 2-3 drops twice a day. I would also give her extra vitamin E in addition to the Nutri-Drench. Once you get her hydrated, see if she will take a little wet mushy chick starter or a little egg.
I would keep her separated from the other chicks. If your brooder is large enough, make a wire barrier so she can still see them. Keep her warm. A stuffed animal, if you have one can be placed in the brooder for her to snuggle with.
You are doing what you can for her. I hope she starts to improve