Standing at the side of the horse and looking at the angle of the coronary band of the hind foot can give you an indication as to what angle the pedal bone is within the hoof capsule. Running a straight line forward from the coronary band it should contact the back of the front leg at about knee height. If this line contacts the front leg above the knee and sometimes as high as the elbow this is indicating that the pedal bone is tipped back at a negative angle.
You can see with Basil this imaginary line from the coronary band would nearly contact the elbow.