When to intervene for a sick chick?

[katelk]

I am currently treating a 5 week old chick for a mystery illness that has been causing her hock joint to buckle forward, making it extremely difficult for her to get around. On top of this symptom, I have noticed her having difficulty keeping her feet under her at times when she loses control due to the hock issue, as if she is doing the splits. Her toes also seem to have more of a tendency to curl than the rest of the chicks, who are all developing great.
She had not yet been able to roost at all.
I have her on Poly-Vi-Sol in hopes that it is just a vitamin deficiency, but have seen no improvement. I have been treating her with this 3 times daily for 3 days now.
Today I decided to isolate her after seeing one of the other chicks peck her. I had taken their toys away because she kept stumbling over them, so I suppose the rest of them became bored!
I am wondering if isolating her is the right thing to do and if it will have any consequences? The others were just running all over her and I figured it was not helping her situation. I now have her in a small plastic washtub lined with paper towels with food and water and a heat lamp. It is small enough to keep with me so she is not alone.
Also, if these symptoms sound familiar to anyone, any info or advice would be greatly appreciated!!

 

[ChickensAreSweet]

http://www.thepoultrysite.com/publications/6/diseases-of-poultry/217/vitamin-b2-deficiency

http://www.merckmanuals.com/vet/pou..._poultry/vitamin_deficiencies_in_poultry.html

Could be curly toe paralysis (riboflavin def.).

http://ps.fass.org/content/52/1/237.abstract

Good for you for giving vitamins!
You might put one chick in with her for company if that chick will leave her alone and not peck...judgement call on your part.