title: Avascular bone necrosis of the hip joint after solid organ transplantation in childhood: a clinical and MRI analysis.
abstract: BACKGROUND
  Aseptic osteonecrosis is a well-known complication after solid organ transplantation in adults. The occurrence of osteonecrosis in growing age has been studied after kidney transplantation, but no systematic evaluation of the joints has been reported after heart or liver transplantation in childhood.
  
  
  METHODS
  A total of 196 children--93% of patients surviving kidney, liver and heart transplantation in Finland--participated in a cross-sectional survey. All children underwent a detailed clinical examination and filled out a questionnaire on musculoskeletal symptoms. Radiographs were taken in case of joint pain or abnormal clinical findings. In addition, magnetic resonance imaging (MRI) from the hips was taken on a random basis from 34 adult patients transplanted as a child. The mean follow-up time of all patients after transplantation was 9.2 years (range, 2.4 to 20.5 years).
  
  
  RESULTS
  Twenty-eight (14%) patients reported prolonged joint or limb pain without previous trauma. Specific etiology for the limb pain was not found in 10 (5.1%) patients. Osteonecrosis seen in radiographs or MRI was noted in seven (3.6%) patients, of which three had received kidney, three liver, and one heart graft. Femoral head was affected in five patients, as well as talus bilaterally in one patient and lateral femoral condyle in one patient. All patients were older than 12 years at the time of diagnosis of the osteonecrosis. MRI of the hips of 34 randomly selected patients showed only one asymptomatic necrosis of the femoral head.
  
  
  CONCLUSIONS
  Symptomatic osteonecrosis of the hip is uncommon after solid organ transplantation in childhood using the current immunosuppressive medications.
authors.affiliation: Hospital for Children and Adolescents, Helsinki University Central Hospital, Helsinki, Finland. ilkka.helenius@helsinki.fi
authors.forename: Ilkka
authors.initials: I
authors.lastname: Helenius
authors.forename: Hannu
authors.initials: H
authors.lastname: Jalanko
authors.forename: Ville
authors.initials: V
authors.lastname: Remes
authors.forename: Pekka
authors.initials: P
authors.lastname: Tervahartiala
authors.forename: Sari
authors.initials: S
authors.lastname: Salminen
authors.forename: Heikki
authors.initials: H
authors.lastname: Sairanen
authors.forename: Christer
authors.initials: C
authors.lastname: Holmberg
authors.forename: Miia
authors.initials: M
authors.lastname: Helenius
authors.forename: Yrjänä
authors.initials: Y
authors.lastname: Nietosvaara
authors.forename: Jari
authors.initials: J
authors.lastname: Peltonen
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D016027:Heart Transplantation; D006621:Hip Joint / Q000473:pathology*; D006801:Humans; D016030:Kidney Transplantation; D016031:Liver Transplantation; D008279:Magnetic Resonance Imaging; D008297:Male; D010020:Osteonecrosis / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography