title: Fracture following lower limb lengthening in children: a series of 58 patients.
abstract: BACKGROUND
  Fracture is one of the main complications following external fixator removal used in cases of progressive lower limb lengthening; rates as high as 50% are found in the literature. The aim of this study was to determine the factors influencing this complication.
  
  
  METHODS
  One hundred and eleven cases of lower limb lengthening were performed in 58 patients (40 femurs and 71 tibias). The mean age at surgery was 10.1years old. Lengthening was performed in all cases with an external fixator alone, associated in 39.6% of cases with intramedullary nailing. The patients were divided into three groups according to disease etiology (congenital, achondroplasia and other). The fractures were classified according to the Simpson classification.
  
  
  RESULTS
  Twenty fractures were recorded (18%). Sixteen fractures were found in patients with congenital disease, four with achondroplasia and none in the group of other etiologies. The fracture was more often in the femur (27.5%) than in the tibia (12.7%).
  
  
  CONCLUSIONS
  The rate of fracture is influenced by different factors depending on the etiology of disease. In congenital diseases, the fracture rate is higher when there is lengthening of more than 15% of the initial length and a delay between surgery and the beginning of lengthening of less than 7days. In patients with achondroplasia, the influence of a relative percentage of lengthening is less important than in those with congenital disease. However, to avoid fractures, lengthening should not be started in children under the age of nine. Moreover, lengthening should begin at least 7days after the fixator has been placed.
  
  
  METHODS
  Retrospective.
  
  
  METHODS
  Level IV.
authors.affiliation: Timone Children Hospital, Department of Pediatric and Orthopaedic Surgery, 264, rue Saint-Pierre, 13385 Marseille cedex 5, France. franck.launay@ap-hm.fr
authors.forename: F
authors.initials: F
authors.lastname: Launay
authors.forename: R
authors.initials: R
authors.lastname: Younsi
authors.forename: M
authors.initials: M
authors.lastname: Pithioux
authors.forename: P
authors.initials: P
authors.lastname: Chabrand
authors.forename: G
authors.initials: G
authors.lastname: Bollini
authors.forename: J-L
authors.initials: JL
authors.lastname: Jouve
mesh_terms: D000130:Achondroplasia; D000293:Adolescent; D001852:Bone Lengthening / Q000009:adverse effects*; D001861:Bone Regeneration; D002648:Child; D002675:Child, Preschool; D016267:External Fixators; D005260:Female; D005269:Femur / Q000601:surgery*; D005594:Fracture Fixation, Intramedullary; D050723:Fractures, Bone / Q000209:etiology*; D006801:Humans; D007870:Leg Length Inequality / Q000209:etiology / Q000601:surgery; D008297:Male; D012189:Retrospective Studies; D013977:Tibia / Q000601:surgery*; D055815:Young Adult