No, the whole point of that has always been for the anchor-points and leverage.
Presumably, the cybertorso can flex, though. Can you imagine if the guy's whole body was rigid from neck to hip? Ouch. Presumably, some kind of flexible or articulated material is used for the 'shell'.
Anyway, I agree that the spine, ribs, and muscles would *have* to be replaced for the cybertorso to be functional like a cyberlimb, movement-wise. And it's not a 'shell' at that point (aside: I wonder if you need blood transfusions when you no longer have any real bones…).