I've added a new request on JIRA today:
https://jira.secondlife.com/browse/VWR-1573
The purpose is to add an option on the Client menu to force the viewer to load your shape again, instead of using the default "Ruth" shape. Looking at the viewer's source code, what seems to be happening is that when the viewer cannot retrieve your shape from the servers, it'll "create" a new shape for you (temporarily) — a Ruth shape — and wears it instead. The idea is that you should never be "shapeless" in SL and could then try to load another shape, after you get a default one.
Alas, this fails with "Can't change appearance or shape until clothing and shape are loaded". So this means that you'll stay Ruthed for that session.
The usual workaround is to log out, clear the cache manually, and try again, on a less busy sim. In almost all cases this will work flawlessly. But it's a mess, specially if almost all code to do a "force shape reload" is already in the viewer's code. All we need is an extra option on the Client menu — it already has a "force load" for default male and female shapes, it would be nice to have one to "force load" your own shape as well.