This is an unusual problem on a herd basis. I think you are dealing with a nutritional deficiency and/or genetic component. Hip dysplasia is a well-recognized genetic disorder in other species (especially dogs), but I'm not familiar with that being the case with cattle. If their bones are weak or develop improperly due to lack of calcium in the diet (or a calcium-phosphorus imbalance), that might cause the problems you are seeing. I hope you have someone who can help you formulate a balanced diet, especially for your young animals. They sound like they need calcium supplementation, but other mineral deficiencies could be involved instead or in addition. The animals might be breaking their bones and displacing their hips if their bones are improperly calcified—weak bones might not be able to withstand even minor trauma such as cattle riding each other.