not sure if this will help your pup but I think it may be worth a shot to try it.
Myth - A hearty diet helps avert dog hip dysplasia.
Fact To the contrary, dogs that are genetically predisposed to hip dysplasia seem to benefit from a lean diet during their first two years. In one study beginning at eight weeks of age, pups that were restricted to a 24-percent smaller ration had a 46-percent lower occurrence of hip dysplasia than pups that could eat freely. Slowing the growth rate during the early months of life, some veterinary nutritionists now believe, can lessen the severity of hip dysplasia and even prevent it.
http://www.yourdoghealth.com/canine_hip_dysplasia_myths.htm
http://www.yourdoghealth.com/canine_hip_dysplasia.htm