Do chicken bones need to be fully cooked to be allowed to further heat the chicken or the dish that they are in?
If one, or the majority of one’s city, is accustomed to eating the chicken bones, then the chicken bones must be cooked to the point that they are chewable. If neither oneself nor the majority of one’s city eats them, they do not need to be cooked. If one is in doubt as to whether they have been cooked to the point that they are chewable, then if he himself does not chew them, even if majority of the city does, he is not required to be stringent.
 Rav SZ”A in Minchas Shlomo 6; Shabbos Kehalacha Vol. 1 p. 200; See SSH”K 1:18; Piskeiy Teshuvos 253:18; See Minchas Yitzchak 8:25
Other Opinions: Some Poskim rule there is no cooking prohibition involved in bones. [Igros Moshe 4:76]