What is wrong with my chicken, “Pepper”?

[Rcpopart]

After looking at the videos, she is definitely trying to walk on the leg. Mareks could be a possibility, or an injury to her leg which could affect her sciatic nerve or hip. I would separate her in a dog crate with food and water close by where she can reach them. That will force her to rest the leg. You could also try a chicken sling chair if she will tolerate it. Food and water can be placed right in front of her. Here in post 5, 11, and 12 are good pics and a video of slings and the design:
https://www.backyardchickens.com/threads/versions-of-chick-chairs-please.1166308/

Update: She may have broken her leg. Thoughts? Treatment?

 

[Eggcessive]

Is that her joint? It looks like a recent injury. Can you clean up her feet so that we could tell if she has bumblefoot on her pads? Soaking in a dish pan of warm soapy water can do the trick. I would paint the leg wound with disinfect.

 

[Rcpopart]

At this point, we are thinking she broke her hip and the recent red mark is just wear and tear from resting on her hock. The entire leg seems non functioning and is dragging. She is still eating healthy and laying eggs even!

She's a tough girl.

Wish we knew how to help a broken chicken hip.
maybe chicken sling?