title: The primary stability of pelvic reconstruction after partial supraacetabular pelvic resection due to malignant tumours of the human pelvis: a biomechanical in vitro study.
abstract: BACKGROUND
  Up until now, reconstructions after partial supraacetabular pelvic resection have been done with the use of megaprostheses or allo-/autografs, including screws. The literature states complications in up to 100%. Therefore, the university hospital of Muenster has successfully established a reconstruction using poly-axial screws and titanium rods in combination with a Palacos(®) shroud. The aim of this study was to gather data on primary stability of five different types of reconstruction.
  
  
  METHODS
  Using a biomechanical model Load (N), displacement (mm) and stiffness (N/mm) were recorded in load cycles from 100N up to 1050N.
  
  
  RESULTS
  The data shows that reconstructions with poly-axial screws, titanium rods and Palacos(®) can bear a load of up to 1050N without structural damages. The same is valid with an additional bone graft and for a full metal prosthesis. Referring to reconstructions with just bone graft or without graft and Palacos(®) the load-bearing capacity is significantly worse. Additionally, structural damages were recorded in those reconstructions from 700N onwards.
  
  
  CONCLUSIONS
  Due to the biomechanical results and the save and easy handling, reconstructions with poly-axial screws, titanium rods and Palacos(®) (and, if necessary, bone graft) can be recommended achieving high primary stability for pelvic ring reconstruction after partial supraacetabular pelvic resection.
authors.affiliation: Department of Orthopaedic Surgery, University Hospital Muenster, Albert-Schweitzer-Str. 33, D-48149 Muenster, Germany; Department of Spinal Cord Injuries, University Hospital Bergmannsheil Bochum, Bürkle-de-la-Camp-Platz 1, D-44789 Bochum, Germany.
authors.forename: Mirko
authors.initials: M
authors.lastname: Aach
authors.forename: Carsten
authors.initials: C
authors.lastname: Gebert
authors.forename: Helmut
authors.initials: H
authors.lastname: Ahrens
authors.forename: Ralf
authors.initials: R
authors.lastname: Dieckmann
authors.forename: Georg
authors.initials: G
authors.lastname: Gosheger
authors.forename: Jendrik
authors.initials: J
authors.lastname: Hardes
authors.forename: Martin
authors.initials: M
authors.lastname: Wessling
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D001696:Biomechanical Phenomena; D001859:Bone Neoplasms / Q000601:surgery*; D001863:Bone Screws; D016025:Bone Transplantation; D006801:Humans; D055595:Mechanical Phenomena; D010388:Pelvis / Q000601:surgery*; D019736:Prostheses and Implants; D019651:Plastic Surgery Procedures / Q000379:methods*; D014025:Titanium
chemical_list: D014025:Titanium
keywords: Biomechanical study; Pelvic ring reconstruction; Pelvic tumour; Primary stability