In a preferred form the invention there is a lateral support forming part of a seat of a wheelchair, comprising a bracket (1), a hinge body (2), a forward plate (3) having padding and a lever (17). The lever (17) is arranged so it can be turned by hand to move a bolt (18) into a pin (5) whereby the hinge body is prevented from swinging about the pin. The lever (17) is also arranged so it can be subsequently turned by hand to cause a cam face (21) of the lever to ride along a complimentary engaging surface (22) of the hinge body. This forces the bolt (18) from the pin (5) thereby freeing the hinge body (2) to swing about the pin (5) and, as a consequence, to swing the plate (3) to facilitate access to the seat.