Good hips and elbows greatly reduces the risk of the dog developing hip or elbow problems, which can be an issue with larger-breed dogs.
All breeding stock have been hip- and elbow-scored if the breeder is reputable, and of course we organise the scores for our breeding stock. Also, many generations before them will have been scored too.
We use the AVA (Australian Veterinary Association) system, where lower scores are better and 0 is a perfect score.