The best thing you can do is get a dog from a reputable breeder who will disclose any history of back problems in the line.
Keeping the dog fit and at a suitable weight is very valuable for maintaining back health. Also not letting the dog jump up and down from sofa's and beds, etc. This requires diligent training. They make ramps or stairs for these type dogs to get in and out of your bed or on the sofa.
Have you ever thought of doing Earthdog trials with your teenie weenie? They are lots of fun.
