Chan was filming a scene in which he slides down a pole in a shopping mall. He ended up cracking his seventh and eighth vertebrae and dislocating his pelvis (which was previously thought impossible)!

During that same scene he also received burns on his hands from the Christmas tree lights. 

He was also found not breathing after a stunt where flips over the balcony and crashes through the glass and light display. He had to go to the hospital for that, too. 

The producers used stunt "sugar glass" which is twice as thick as ordinary stunt glass. Unfortunately this also led to a higher injury rate among stuntpeople. They used so much of it, the crew started referring to the film as "Glass Story". 

Cracked has a color-coded map) that details all of Jackie Chan's injuries. (Surprise! It's most of his body). 

Here's a scene from "Police Story". See if you can count how often people get thrown through glass.