title: Periprosthetic fractures: concepts of biomechanical in vitro investigations.
abstract: OBJECTIVE
  Experimental in vitro studies investigating periprosthetic fractures after joint replacement are used increasingly. The purpose of this review was to deliver a condensed survey of studies in order to provide researchers with an overview of relevant scientific results and their clinical relevance.
  
  
  METHODS
  A literature search was conducted to obtain all available papers dealing with periprosthetic fractures, with particular attention being paid to articles with an experimental research design. Study goals, scientific methods and results, their interpretation and clinical relevance were assessed and compared. The main focus was on comparability with clinical fracture patterns and physiological joint loads.
  
  
  RESULTS
  Excluding duplicates, 24 studies with regard to artificial hip, knee and shoulder joints were found dating back to August 2000. Almost all studies were performed quasi-statically and without consideration of muscle forces and thus reflect selected loading conditions and no dynamic situation during activities of daily living (ADL). Various experimental protocols were used, differing in the choice of experimental material, implant and fixation system and load application.
  
  
  CONCLUSIONS
  In vitro studies regarding periprosthetic fracture research allow controlling for disturbances, such as clinically occurring risk factors like reduced bone mineral density (BMD) or greater patient age. Notwithstanding, due to methodological differences, comparisons between studies were possible to a limited degree only. For this reason, and because of quasi-static loading typically applied, results can only be partially applied to clinical practice.
authors: Laboratory for Biomechanics and Biomaterials (LBB), Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, 30628, Hannover, Germany. Jakubowitz.Eike@mh-hannover.de.
authors: Eike
authors: E
authors: Jakubowitz
authors: Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstrasse 33, 35392, Giessen, Germany.
authors: Jörn Bengt
authors: JB
authors: Seeger
mesh_terms: D019643:Arthroplasty, Replacement / Q000009:adverse effects*; D001696:Biomechanical Phenomena; D006801:Humans; D057068:Periprosthetic Fractures / Q000209:etiology / Q000503:physiopathology*; D012307:Risk Factors
keywords: Arthroplasty; Biomechanics; Fracture load; In vitro experiments; Periprosthetic fracture