Experience w/hip dysplasia....
I don't have any specific advice for elbow dysplasia, but we did manage my lab's hip dysplasia for 10 years w/o surgery so maybe the management may similar enough....
-We kept Sonny's (lab) weight on the lower end and fed him diet dog food
-glucosamine chondroitin tablets (from Foster & Smith) twice a day in his food according to directions (he was 4 tablets a day)
-exercise while keeping an eye on his stiffness and comfort level. LOTS less exercise as he got older and stiffer
-Always worse in the winters (he would sleep with his butt on the heating vents

)
-Occasional Buffered Aspirin for pain management
-Sonny needed assistance getting onto beds, into cars, and up/down stairs when he got older (last 1-2 years). He'd pop his front end on the bed/car seat and wait for us to pick up his rear for him. He also completely stopped going up and down stairs.
-Hardwood floors were an issue as he got older- we had a bunch of rugs and mats in strategic locations in the kitchen and dining room since he would lay down and then have trouble getting up on the wood/tiled surfaces (only the last couple of years) and he would occasionally loose his footing/hind legs the last year.
Sonny was very happy and playful and really did not have too many issues until he got older. Oh, and he loved getting the ouchy (swollen) parts of his hips gently massaged on colder/rainy days when they bothered him more.
I hope some of this may help! Kisses for your boy