20 y/o Quarab possibly affected w/DE

From the HGS forums:

 

"I have a very handsome 20 yr old Quarab gelding, who was my first horse, and is showing signs of his age. He has dropping fetlocks, which forced us to put him into a semi-retired life style. At first they wern't that bad, but now as he gets older they are dropped a lot, and basically touch the ground when he moves. His back legs are the worst..."

.