In collaboration with @Charlie Wooster , I have written an article on treating splay leg in quail chicks.
https://www.backyardchickens.com/articles/treating-splay-leg-in-quail.78692/
https://www.backyardchickens.com/articles/treating-splay-leg-in-quail.78692/

Treating Splay Leg in Quail
The best treatment, is, of course to prevent it in the first place. Some things that will help with this are providing good footing in the incubator and brooder. Grippy shelf liner works well for this. Paper towels with a lot of texture may work as well. Avoid newspaper, smooth paper towels...