Obviously, anyone with osteoporosis can tell you that bones can be too soft. But can bones be too hard? I thought that this may be possible because part of cushioning we get when we do everything from walking to jumping, comes from the flexing/compressing of bones (however small). The rest comes from the joints and the muscles. What happens in people with an abundance of osteoblasts but too few osteoclasts? Are their bones too hard, and do their joints suffer as a result?