Lennie, what "grade" of luxation did the vet say your dog had? From what I've read, the condition can be very mild (level 1, only rare difficulties with the leg) or can be severe (level 5, complete inability to use the leg at all). Most vets suggest that a grade 1 or 2 doesn't need surgery, but a 3 or higher should have the surgery. I also know that with age and time it's supposed to get worse as the bones and connective tissue wear down.

Maybe your pup's condition was so mild that it went away as the joints grew? I dunno, just guessing. You might try asking this on a newsgroup like alt.med.veterinary, where vets and folks like that might have ideas.

Glad she's better, though!