Her lower legs are kindof fat (below the knee) -- you know how when some chicks get fat and then their ankles disappear? She's got that problem... look how in every pic they hid that part of her leg, or came up with a creative angle, or did editing...
in this pic
http://www.maximonline.com/girls/jeri_ryan/gm_l4.jpg
they even used those wierd black elastic things to give the impression that she has ankles...