title: Densitometric study of the clavicle: bone mineral density explains the laterality of the fractures.
abstract: BACKGROUND
  Epidemiological studies have shown laterality in clavicle fractures, such that the left side is more frequently fractured. The present study had the aim of evaluating whether the clavicle on the dominant side is denser and thus explaining the greater incidence of fractures on the non-dominant side.
  
  
  METHODS
  This was a descriptive study on 52 healthy patients, who were classified according to age, sex and whether the dominant or non-dominant side was affected.
  
  
  RESULTS
  The participants comprised 28 women (53.8%) and 24 men (46.2%). Regarding the dominant side, 30 were right-handed (57.7%) and 22 were left-handed (42.3%). The mean age was 25 years. In this study, it could be seen that the non-dominant side had greater bone mass than the dominant side. It was also observed that the bone density was greater in the middle and distal thirds on the non-dominant side, with a statistically significant difference. In the women, the density was also greater on the non-dominant side; this difference was not significant in relation to the dominant side, but there were significant differences between the middle thirds (p < 0.001) and the distal thirds (p < 0.006).
  
  
  CONCLUSIONS
  Variations in bone density, toward higher and lower bone mass, may have been responsible for the fractures. According to the findings from this study, fractures occur more in the middle third of the non-dominant clavicle, as a result of greater bone mineral mass, which gives rise to lower flexibility and fractures in the region.
authors.affiliation: Serviço de Ortopedia, Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Teodoro Ezequiel Guerra
authors.affiliation: Grupo do Ombro e Cotovelo, Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: Maria
authors.initials: M
authors.lastname: Isabel Pozzi
authors.affiliation: Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Busin
authors.affiliation: Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Crestana Zanetti
authors.affiliation: Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: José
authors.initials: J
authors.lastname: Antônio Lazzarotto Terra Lopes
authors.affiliation: Hospital Universitário, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil.
authors.forename: Vinícius
authors.initials: V
authors.lastname: Orso
keywords: Bone fracture; Clavicle; Densitometry; Physiopathology