title: The natural history of heterotopic ossification in patients who have fibrodysplasia ossificans progressiva. A study of forty-four patients.
abstract: Forty-four patients who had fibrodysplasia ossificans progressiva responded by mail to a questionnaire regarding the age at the onset of heterotopic ossification at fifteen commonly involved anatomical sites. The average age of the patients when they responded to the questionnaire was twenty-seven years (range, three to sixty-nine years). The average age at the onset of ossification was five years (range, birth to twenty-five years). The most common sites of early heterotopic ossification were the neck, spine, and shoulder girdle. Thirty-five (80 per cent) of the patients had had some restrictive heterotopic ossification by the age of seven years. By the age of fifteen years, forty-two (more than 95 per cent) of the patients had severely restricted mobility of the upper limbs. In these patients, heterotopic ossification proceeded in a direction that was axial to appendicular, cranial to caudad, and proximal to distal; this pattern appeared typical for fibrodysplasia ossificans progressiva.
authors.affiliation: Department of Orthopaedic Surgery, Hospital of the University of Pennsylvania, Philadelphia 19104.
authors.forename: R B
authors.initials: RB
authors.lastname: Cohen
authors.forename: G V
authors.initials: GV
authors.lastname: Hahn
authors.forename: J A
authors.initials: JA
authors.lastname: Tabas
authors.forename: J
authors.initials: J
authors.lastname: Peeper
authors.forename: C L
authors.initials: CL
authors.lastname: Levitz
authors.forename: A
authors.initials: A
authors.lastname: Sando
authors.forename: N
authors.initials: N
authors.lastname: Sando
authors.forename: M
authors.initials: M
authors.lastname: Zasloff
authors.forename: F S
authors.initials: FS
authors.lastname: Kaplan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009221:Myositis Ossificans / Q000473:pathology*; D009999:Ossification, Heterotopic / Q000473:pathology*