title: Supracondylar humerus fractures in children: the effect of weather conditions on their risk.
abstract: BACKGROUND
  Supracondylar humerus fractures are the most common fractures of the elbow in children. Many environmental factors such as weather conditions may affect the risk of these fractures. The purpose of the study was to analyze the effect of weather conditions (temperature, rainfall, wind) on fracture risk in children <16 years of age during the extended summer time period with the absence of snow cover.
  
  
  METHODS
  All children <16 years of age with an outdoor supracondylar humerus fracture between May 1 and September 30 in a defined geographical area during the decade of 2000-2009 were included. Daily meteorological recordings for altogether 1526 study days were reviewed from the national weather service and the association of weather conditions and fractures were analyzed.
  
  
  RESULTS
  A majority (79.7%, N = 181) of the fractures occurred on dry days versus rainy days (20.3%) (P = 0.011), and risk of a fracture was 3.5-fold higher on dry days as compared with rainy days (crude OR 3.5, 3.41-3.59, P < 0.001). The weather was warm, instead of cool or hot, when the majority of the fractures (N = 147, 64.8%) occurred (P = 0.008): Warm temperatures (15-24.9 °C) increased the fracture risk 2.6-fold (crude OR 2.64, 2.59-2.70, P < 0.001), compared with cool (<15 °C) days. The fracture incidence did not change according to the wind speed (P = 0.171). The findings were similar through the school term and summer vacation.
  
  
  CONCLUSIONS
  Dry and warm weather conditions increase the risk of outdoor supracondylar humerus fractures in children during the time period with the absence of snow cover.
authors.affiliation: Department of Children and Adolescents, Pediatric Surgery and Orthopedics, Oulu University Hospital, POB 23, 90029, Oulu, Finland. juha-jaakko.sinikumpu@ppshp.fi.|PEDEGO Research Group, Oulu University Hospital, Oulu, Finland. juha-jaakko.sinikumpu@ppshp.fi.|Oulu University Medical Research Center, Oulu University, Oulu, Finland. juha-jaakko.sinikumpu@ppshp.fi.
authors.forename: Juha-Jaakko
authors.identifier: http://orcid.org/0000-0003-1870-4420
authors.initials: JJ
authors.lastname: Sinikumpu
authors.affiliation: Department of Children and Adolescents, Pediatric Surgery and Orthopedics, Oulu University Hospital, POB 23, 90029, Oulu, Finland.|PEDEGO Research Group, Oulu University Hospital, Oulu, Finland.|Oulu University Medical Research Center, Oulu University, Oulu, Finland.
authors.forename: Tytti
authors.initials: T
authors.lastname: Pokka
authors.affiliation: Department of Children and Adolescents, Pediatric Surgery and Orthopedics, Oulu University Hospital, POB 23, 90029, Oulu, Finland.|PEDEGO Research Group, Oulu University Hospital, Oulu, Finland.|Oulu University Medical Research Center, Oulu University, Oulu, Finland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Hyvönen
authors.affiliation: Finnish Meteorological Institute, Helsinki, Finland.
authors.forename: Reija
authors.initials: R
authors.lastname: Ruuhela
authors.affiliation: Department of Children and Adolescents, Pediatric Surgery and Orthopedics, Oulu University Hospital, POB 23, 90029, Oulu, Finland.|PEDEGO Research Group, Oulu University Hospital, Oulu, Finland.|Oulu University Medical Research Center, Oulu University, Oulu, Finland.
authors.forename: Willy
authors.initials: W
authors.lastname: Serlo
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005387:Finland / Q000453:epidemiology; D006801:Humans; D006810:Humeral Fractures / Q000209:etiology*; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D012307:Risk Factors; D012621:Seasons; D014887:Weather
keywords: Children and adolescents; Climate; Seasonal variation; Supracondylar humerus fracture; Weather