tokens: The most frequently reported disorders were Marfan syndrome , osteogenesis imperfecta , fibrous dysplasia , mucopolysaccharidosis , multiple cartilaginous exostoses , neurofibromatosis type 1 ( NF1 ) , osteopetrosis , achondroplasia , enchondromatosis ( Ollier ) , and osteopoikilosis , accounting for 76.5 % ( 12,312 cases ) of the total cases .