Welcome to spine.
Firstly, It is possible... Secondly, its not easy.
The main problem here are you cant have masks in spine. And as you asked in the editor forum, ill try and give an editor answer (not that I can give a detailed answer of a programmy way to do it, sorry)
According to your image, really, the only thing you will see moving is the spokes (bars from centre to edge). I would separate them into different slots, then rotate them around the centre of the wheel.
To do this click the image, then use rotate tool, then click the + in the centre of the rotate icon and drag it to the wheel centre
once it hits 0' you can snap it to the otherside (although because of the image I doubt you need to do that as you can just loop the spokes moving to the next spokes position)
