Heterotopic ossification (HO), deposition of para-articular ectopic bo
ne, is associated with musculoskeletal trauma and certain congenital a
nd metabolic disorders. Additionally, HO may follow paralysis from div
erse traumatic and nontraumatic neurologic insults. We describe three
cases of HO associated with catastrophic nontraumatic respiratory illn
ess requiring prolonged chemical paralysis and cardiorespiratory suppo
rt.