title: [New from old : relevant factors for fracture healing in aging bone].
abstract: BACKGROUND
  Fracture healing is a complex biological process with specific temporal expression patterns. During this process new bone tissue is formed, which is similar to the original bone in quality and structure. This occurs in four phases: inflammation, formation of a soft tissue callus, formation of a bony callus and remodelling of the bony callus. This needs the precise orchestration of each cell type involved.
  
  
  OBJECTIVE
  This article presents details of the fracture healing phases and the relevant factors. During the aging process there is an increase of reactive oxygen species and a change in expression pattern of growth factors that have a negative effect on the fracture healing process.
  
  
  METHODS
  A selective review of the literature was carried out in PubMed concerning the influence of aging on fracture healing.
  
  
  CONCLUSIONS
  The healing process is regulated by systemic and local factors. An understanding of these processes and the changes during aging is necessary in order to improve the knowledge of delayed or lack of fracture healing during aging to decide when an intervention is needed.
authors.affiliation: Institut für Anatomie und Zellbiologie, Universitätsklinikum der RWTH Aachen, Wendlingweg 2, 52074, Aachen, Deutschland, rbeckmann@ukaachen.de.
authors.forename: R
authors.initials: R
authors.lastname: Beckmann
authors.forename: M
authors.initials: M
authors.lastname: Tohidnezhad
authors.forename: P
authors.initials: P
authors.lastname: Lichte
authors.forename: C J
authors.initials: CJ
authors.lastname: Wruck
authors.forename: H
authors.initials: H
authors.lastname: Jahr
authors.forename: H C
authors.initials: HC
authors.lastname: Pape
authors.forename: T
authors.initials: T
authors.lastname: Pufe
mesh_terms: D000375:Aging / Q000378:metabolism*; D016723:Bone Remodeling / Q000502:physiology*; D005260:Female; D017102:Fracture Healing / Q000502:physiology*; D050723:Fractures, Bone / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008954:Models, Biological; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D017382:Reactive Oxygen Species