Won't walk, listless pullet

[Giaallen]

i have a 5 year old black sexlink that suddenly went lame on her left side. oddest thing ever. i thought it was mareks to be honest but she has not gotten worse, nor better. she's hanging with her friends with a small splint on her foot but predominantly hops on one leg and gets around the coop just fine. she even puts herself to bed in the nesting boxes since she knows she can't get up on the roost. i am hopeful she won't get worse, but also, i'm not sure what quality of life this is. she seems "fine" and her leg is warm to the touch as usual. she eats, drinks, poops all the same but has absolutely stopped laying (which is fine). I just started vitamin B yesterday to see if maybe that will help. any other suggestions? she's the sweetest girl