Joey becomes unnerved when he hears about them and reveals to Monica and Phoebe that he also used to date her and did a horrible thing: Ginger has an artificial leg and in the middle of the night, he accidentally threw it onto a fire. Phoebe and Monica are both mortified after hearing this, with Monica exclaiming "She must've freaked out!". Joey responds with "Yeah. She must've..." As it turns out, once he discovered what he had done, he made a run for it, never to speak with her again.
When Chandler learns of Ginger's artificial leg, it freaks him out. He tries to get over it and after a little convincing from Ginger is able to. However, after she learns about his "nubbin", she is too freaked out by it to continue their relationship.