Can you link the picture that looked similar to your bird? How old is she? What type? Is she a broiler? Any possibility she jumped down from a high roost?
On the curled toes, I'd go ahead and give her B vitamins in case it's B-vitamin "Curled toe". Go to the store,
Walmart or similar, and buy a bottle of B-complex vitamins, of E vitamins (oil capsules, 400 IU), and a bottle of PolyViSol baby vitamins, not the iron fortified kind. All of these items are in the vitamin section of
Walmart for example, or other pharmacies, etc. Buy a container of plain yogurt - big is better and cheaper as you can feed it to your other birds - more on that in a bit.
I'd keep the hen up in a smaller area so she doesn't have to use her leg. Feel the leg for heat. Compare it to the other. Make sure she has free choice crumbles and water all day.
You'll want to make a small amount of a "damp mash" for her to eat first thing each day. Mix 1 teaspoon of yogurt, part of a boiled egg yolk (no whites - feed those to your other birds), 1 crushed B-complex capsule, and the contents of the E vitamin. Stir well. Mix that with 2 tablespoons of cooked oatmeal. Feed that to her. If she doesn't like the wet texture, do the same but with 1 tablespoon of water and her crumbles instead of the cooked oatmeal. Let sit 10 minutes to absorb. And if THAT doesn't work, try mixing boiled egg yolk mashed with the B-complex vitamin, and simply squirt the contents of the E vitamin into the side of her beak. Removing her feed 20 minutes before giving the damp mash really helps encourage them to eat it. (2 drops if she's young, the whole thing if she's older). She'll get 2-3 drops of polyvisol in the side of the beak. (2 if she's younger, 3 if she's older.)
The B vitamins will correct a deficiency in choline or riboflavin which can cause something like this. The egg yolk is a source of Managanese which, if deficient, can cause "perosis" or slipped tendon disorder in poultry. The E vitamins help with any neurological impairment (as her toes are curling). The yogurt provides yet more riboflavin as well as living bacteria which support healing. The polyvisol contains B vitamins and other vitamins, including D in case there was a D deficiency causing rickets. The oatmeal - well they just really like it. All of these vitamins can help if this is nutritional. They can also help healing if this was an injury. The answers to the questions about type and diet (below) will help me rule out broiler leg issues or heavy weight issues.
Can you also tell us what type of birds she is? (Broiler type, laying type, etc), how old she is, what feed exactly she's getting, including protein level, and if she gets it free-choice or fed twice a day? Are her legs at all 'bowed', her beak at all limber, her toenails at all soft?
There are some things that cause slipped tibia but we need a little more information.
OK Shopping list:
B-complex tablets
E vitamin oil capsule (400 IU)
polyvisol baby vitamins (Enfamil brand, NON-iron fortified - vitamin section)
plain yogurt
Oatmeal if you don't have it
eggs if you don't have them.