if there's a technology/medical use for need, it will eventually be used to satisfy a desire. but then again, there is such a fine line between need and desire nowadays. leg lengthening, pioneered by Gavril Abramovich Ilizarov in 1951 to treat people with orthopaedic problems, is now not only used by dwarfs but anybody who feels that being taller (or shorter) is better. women in China are pressured to break their bones to please their boyfriends, get into law school, and increase their job opportunities.