title: COMPARISON OF VOLUMES OCCUPIED BY DIFFERENT INTERNAL FIXATION DEVICES FOR FEMORAL NECK FRACTURES.
abstract: OBJECTIVE
  The objective of this paper is to measure the volume occupied by the most widely used internal fixation devices for treating femoral neck fractures, using the first 30, 40 and 50 mm of insertion of each screw as an approximation. The study aimed to observe which of these implants caused least bone aggression.
  
  
  METHODS
  Five types of cannulated screws and four types of dynamic hip screws (DHS) available on the Brazilian market were evaluated in terms of volume differences through water displacement.
  
  
  RESULTS
  Fixation with two cannulated screws presented significantly less volume than shown by DHS, for insertions of 30, 40 and 50 mm (p=0.01, 0.012 and 0.013, respectively), fixation with three screws did not show any statistically significant difference (p= 0.123, 0.08 and 0.381, respectively) and fixation with four cannulated screws presented larger volumes than shown by DHS (p=0.072, 0.161 and 0.033).
  
  
  CONCLUSIONS
  Fixation of the femoral neck with two cannulated screws occupied less volume than DHS, with a statistically significant difference. The majority of screw combinations did not reach statistical significance, although fixation with four cannulated screws presented larger volumes on average than those occupied by DHS.
authors.affiliation: Resident Physician, Irmandade da Santa Casa de Porto Alegre - ISCPA - Porto Alegre, RS, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Lauxen
authors.affiliation: Full Professor of Orthopedics and Traumatology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA) and of the Orthopedics and Traumatology Clinic, Irmandade da Santa Casa de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Schwartsmann
authors.affiliation: Professor, Universidade Federal de Ciências da Saúde de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Marcelo Faria
authors.initials: MF
authors.lastname: Silva
authors.affiliation: Assistant Physician, Hip Surgery Clinic, Irmandade da Santa Casa de Misericórdia de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Leandro de Freitas
authors.initials: Lde F
authors.lastname: Spinelli
authors.affiliation: Coordinator, Physical Metallurgy Laboratory, Universidade Federal do Rio Grande do Sul - LAMEF/UFRGS - Porto Alegre, RS, Brazil.
authors.forename: Telmo Roberto
authors.initials: TR
authors.lastname: Strohaecker
authors.affiliation: Physical Metallurgy Laboratory, Universidade Federal do Rio Grande do Sul - LAMEF/UFRGS; Master's Degree from the Universidade Federal do Rio Grande do Sul - Porto Alegre, RS, Brazil.
authors.forename: Ralf Wellis de
authors.initials: RW
authors.lastname: Souza
authors.affiliation: Master's Degree Student in Material Sciences, Universidade Federal do Rio Grande do Sul - Porto Alegre, RS, Brazil.
authors.forename: Cinthia Gabriely
authors.initials: CG
authors.lastname: Zimmer
authors.affiliation: Assistant Physician, Hip Surgery Clinic, Irmandade da Santa Casa de Misericórdia de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Leonardo Carbonera
authors.initials: LC
authors.lastname: Boschin
authors.affiliation: Assistant Physician, Hip Surgery Clinic, Irmandade da Santa Casa de Misericórdia de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Ramiro Zilles
authors.initials: RZ
authors.lastname: Gonçalves
authors.affiliation: Assistant Physician, Hip Surgery Clinic, Irmandade da Santa Casa de Misericórdia de Porto Alegre - Porto Alegre, RS, Brazil.
authors.forename: Anthony Kerbes
authors.initials: AK
authors.lastname: Yépez
keywords: Femoral Neck Fractures; Fractures Fixation, Internal; Hip/surgery