This was written and originally recorded by a blues singer named Willie Mae "Big Mama" Thornton, who recorded the original version of "Hound Dog." The ball and chain is an image associated with prisoners, as a weighted ball attached to a chain would be shackled to an inmate's leg to keep him from escaping. In this song, Thornton relates the image to her man, who is keeping her down.
Joplin's interpretation of this song solidified her reputation as an incredibly soulful performer who can handle the gnarliest of the Blues. A staple of her live performances, she sang it at the Monterey Pop Festival in 1967 and also at Woodstock. She recorded the song in 1968 with her band Big Brother and the Holding Company, and after her death in 1971, the song appeared on many of her compilation albums. (thanks, Bertrand - Paris, France)