title: Avascular Necrosis in the Contralateral Hip in Patients With Congenital Femoral Deficiency: A Report of 3 Cases.
abstract: BACKGROUND
  Congenital femoral deficiency is an uncommon clinical entity. We report 3 patients who developed avascular necrosis of the hip in the long (normal) leg during longitudinal observation and/or treatment of congenital femoral deficiency.
  
  
  METHODS
  Patients were identified in limb length discrepancy clinic and their charts were retrospectively reviewed for clinical and radiographic data collection.
  
  
  RESULTS
  We describe the occurrence of idiopathic avascular necrosis in the normal limb in patients being followed for limb length discrepancy.
  
  
  CONCLUSIONS
  Although no conclusion could be drawn about the etiology of the avascular necrosis, we describe a previously undocumented relationship between congenital femoral deficiency and avascular necrosis in the contralateral hip. This occurred in our congenital femoral deficiency population at a rate higher than expected compared with published incidences of avascular necrosis of the hip in children.
  
  
  METHODS
  Level IV-case series.
authors.affiliation: Texas Scottish Rite Hospital for Children, Dallas, TX.
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Brown
authors.forename: Robert L
authors.initials: RL
authors.lastname: Wimberly
authors.forename: John G
authors.initials: JG
authors.lastname: Birch
mesh_terms: D000359:Aftercare; D001852:Bone Lengthening / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D019468:Disease Management; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D005271:Femur Head Necrosis / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007870:Leg Length Inequality / Q000150:complications / Q000151:congenital / Q000175:diagnosis / Q000601:surgery; D008297:Male; D011859:Radiography / Q000379:methods; D012189:Retrospective Studies; D016896:Treatment Outcome