A continuous passive motion apparatus is disclosed which comprises a thigh support (40) connected by a hinge structure (38) to a base plate (36). The plate (36) is itself connected to a base (34). A bladder (54), which inflates to the form of a vertically elongate column, is cyclically inflated and deflated to lift the thigh support (40) in movements about a hinge (46) connecting it to an upper hinge plate (42) of the hinge structure (38). The hinge structure also includes a lower hinge plate (44). A foot support (72) is connected by a cord (68) to the thigh support (40).