Morquio’s disease /môrkē″ōz/ [Luis Morquio, Uruguayan physician, 1867–1935] , a familial form of mucopolysaccharidosis that results in abnormal musculoskeletal development in childhood. Dwarfism, hunchback, enlarged sternum, and knock-knees may occur. The disease may first be evident as the child, learning to walk, displays an abnormal, waddling gait. Also called MPS IV. See also mucopolysaccharidosis.