Monarch Disease Ontology entry MONDO_0009012 (multiple pterygium-malignant hyperthermia syndrome) is malignant hyperthermia-arthrogryposis-torticollisis an extremely rare arthrogryposis syndrome, described in only two pairs of siblings from two unrelated families to date, and characterized by the association of arthrogryposis, congenital torticollis, dysmorphic facial features (i.e. asymmetry of the face, myopathic facial movements, ptosis, posteriorly rotated ears, cleft palate), progressive scoliosis and episodes of malignant hyperthermia. There have been no further descriptions in the literature since 1988. Also known as: froster-Iskenius-Waterson-Hall syndrome, malignant hyperthermia-arthrogryposis-torticollis syndrome.