Hip Dysplasia and Elbow Dysplasia are distinct joint diseases that affect a small but significant percentage of all breeds to a greater or lesser extent.
The larger breeds have historically been more afflicted with hip dysplasia than smaller breeds. The exact causes of these problems have not been fully elucidated but there appears to be a significant genetic/hereditary component.
At the current time there is no easy test or DNA test to tell us which individuals are likely to pass this on to their offspring, despite efforts in this country, Spain and USA to find marker genes.
The best we have is to check the state of the parents and avoid breeding from those individuals that are affected.