the common demoninator we see with guys with joint problems are a few things
1. they simply don't have the genetics for bodybuilding. if you are 6 4 with long lanky limbs i'm sorry but you aren't going to be a bodybuilder. your joints are going to be under strain
2. not enough good fats in their diet
3. too much bad shit in their diets
4. pounding too much in the gym and overtraining
5. not doing maintenance to help joints like inversion table and hot yoga