Increasingly, "short term" disability is the stopgap for displaced blue collar workers. SSDI is rapidly becoming secret Welfare/the new deal:

http://apps.npr.org/unfit-for-work/

http://www.theatlantic.com/business/archive/2013/03/disabili...

States love it because it comes out of federal budgets, and feds love it because it's a social security net that doesn't have the pejorative inklings of "welfare."