Mr. Chester, a heavy beer drinker with a large potbelly, complained of severe lower back pains. After X-ray films were taken, he was found to have displacement of his lumbar vertebrae. What would this...

Mr. Chester, a heavy beer drinker with a large potbelly, complained of severe lower back pains. After X-ray films were taken, he was found to have displacement of his lumbar vertebrae. What would this condition be called, and what would cause it?