Hip dysplasia is not uncommon in many dog breeds, particularly the larger breeds. It is a deformity of the of the hip joint so the bone and socket do not fit snug. It causes rubbing and degeneration of the bone, inflamation and damage to surounding cartalidge. The condition usually leads to arthritus as the bone is grinded down new mishapen bone grows back causing pain. The good news about Canine Hip Dysplasia is that most cases can be treated to help eliminate or decrease pain, allowing fairly normal levels of activity. Very few dogs today have to be put to sleep to alleviate suffering. There are always choices to be made, but the vast majority of affected animals can live quite comfortable lives. Depending on how severe the damege is pain medication and anti-inflammatory drugs can be given. Another very good supplement to give is glueclosamine. Eventually though surgery might be necessary. . . I would suggest talking to the shelter about having him examined by a vet of your choice before officially adopting him. If you are willing to spend a little money to consult with a vetranarian you’ll be able to discuss this guy’s prognosis. This way you can know beforehand if his case is mild or severe and what treatment options are reccommended and at what cost. I hope I haven’t scared you away from adopting this dog because it may only be arthritis misdiagnosed or a mild case of hip dysplasia, only a vet can tell you for sure.