Well my 6yr old GSP started having some issues at end of duck season. Came inside one day from running in the back yard without any sign of injury but after laying down for a while she seemed to come up lame in her back end. Couldnt get up on her own, got me worried but it seemed to have passed by next morning. After that every time she would exert herself either in play or training she would show no limp, gait change or symptom of pain untill she stoped moving for while. Then it was as if her hind legs didnt work, each time symptoms passed within 12hrs or so. So I rested her for bout 3wks, no hunting, no training, no exertion. Started her some Deramaxx got my dad to do some x-rays (he is a vet/im a nurse) no indication of hip or spine injury no indication of dysplasia. Since then there had been no change, every time she exerts herself same thing happens.
Way the symptoms presented had us a bit confused so he had me take her to a very good ortho doc in BR. Final diagnosis was both good and bad. It was no neurological injury due to the spine or hips but she has Bilateral partial CCL tears. So now we are going to try a 6-8 week treatment of NSAIDS (deramaxx) and once a week IM injection of a Glucosamine type medicaton (cant remember the name) with strict rest. After the treatment a challenge to see if the sypmtoms persist or if there was some healing to the CCL. If not then we move on to TPLO. Was sad to here she might be out on Injured reserve for almost a year but glad it is something that is very likely to be corrected and have her back to normal in the end. She is the smartest best hunting dog I've ever had and would hate to retire her from the hunt at such a young age.

Wow that sucks man. I hope ya can get her back hunting.