Abstract: A scoliosis measurement instrument includes the elongated scale bar and fixed and adjustable legs of a universal caliper, an inclinometer mounted on the adjustable leg, and a scoliosis midline rod located at the center mark of a bi-directional distance scale on the scale bar. The fixed leg is movable along the scale bar for positioning its skin contact tip over either the highest point of the rib hump or lumbar bulge or the opposite valley of a subject being examined, and the adjustable leg is movable along the scale bar for positioning at the same but opposite distance from the center mark of the bi-directional scale. The adjustable leg also is movable normal to the scale bar to distances of its skin contact tip from the scale bar greater or less than the distance of the fixed leg tip from the scale bar, to measure the distance between the highest prominence and opposite valley.