Abstract: An adapter assembly for releasably attaching a backrest to a frame member, such as a back cane, of a personal mobility device, such as a wheelchair, includes a clamp that can be releasably clamped on the back cane, and a bracket that can be releasably engaged with the backrest, the bracket having a plurality of openings. A plurality of fasteners extend from the clamp through the openings in the bracket. The fasteners have a first condition securing the bracket from movement relative to the clamp and having a second condition enabling adjustment of both the front to back position and the angular position of the backrest relative to the back cane.