this is a prob ive had with my two recently, both are in there second season, plenty of road work. Its been one leg not both though after a course. one of my dogs was so bad i thought shed broke it. she was prescribed loxicom, 17ml once a day. she ways 17kg. sound as pound one hour later. I gave it 10 days and let her free run. All seems ok now. i did write a post asking if anyone bandages before coursing as i think ive seen this before.
Both legs does sound as if it may down to bony changes, at 15 months you may still find the growth plates are not set yet in that area and could be suffe