I know they mention it in the article itself, but it's not really the first surgery to reduce the size of a snake. The title is misleading. Instead it is perhaps the first surgery requested for the purpose of reducing the size of the snake.
As they did in this instance, a common treatment for Peyronie's disease (which is where you have scar tissue build up in the snake, and it causes it to bend to unnatural degrees, and can cause pain and prevent intercourse) is a surgery that is known to likely cause reduction in length.