
Hi Claire, I have had Irish Setters for thirty years and I've come across something similar to this before. My boy Cassidy, now deceased, had a problem with his knee joints at this exact same age. He was diagnosed by Malcolm Ness, a nationally known Orthopaedic specialist, with Patella Luxation due to tibial tortion. In simple terms it means slipping knee caps because of the rapid growth in a twisting fashion of his tibial bones. In Cassidys case the treatment involved lots and lots of free running and as much jumping as he wanted to do. This kind of exercise strengthened the ligaments of the joint so holding the knee cap in position.
Now I'm not saying Alfie has the same thing, it would be wrong of me to contradict your vet, but you could mention to him that you've heard somebody elses experience and what it turned out to be. That might just make the vet consider other possibilities.
Please let me know how you get on.
Best wishes, Dawn R.:)