Bioengineering (Mar 2023)

Development of a Metaphyseal Non-Union Model in the Osteoporotic Rat Femur

  • Amelie Deluca,
  • Andrea Wagner,
  • Bettina Faustini,
  • Nadja Weissenbacher,
  • Christian Deininger,
  • Florian Wichlas,
  • Herbert Tempfer,
  • Ernst J. Mueller,
  • Andreas Traweger

DOI
https://doi.org/10.3390/bioengineering10030338
Journal volume & issue
Vol. 10, no. 3
p. 338

Abstract

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The aim of this current study was to establish a metaphyseal femoral non-union model in osteoporotic rats by comparing a power tool versus a manual tool for fracture creation. Twelve adult female Sprague Dawley rats were ovariectomized (OVX) and received a special diet for 6 weeks. Biweekly pQCT measurements confirmed a significant reduction in the cancellous and total bone mineral density in OVX rats compared to control (CTRL) animals. After 6 weeks, OVX rats underwent surgery creating a distal metaphyseal osteotomy, either using a piezoelectric- (n = 6) or a manual Gigli wire (n = 6) saw. Fractures were stabilized with a Y-shaped mini-locking plate. Within each group, three rats received Alginate directly into the fracture gap. OVX animals gained more weight over 8 weeks compared to CTRL animals. pQCT analysis showed a significant difference in the volumetric cancellous bone mineral density between OVX and CTRL rats. A histological examination of the osteoporotic phenotype was completed. Radiographic evaluation and Masson–Goldner trichrome staining with the piezoelectric saw failed to demonstrate bony bridging or a callus formation. New bone formation and complete healing were seen after 6 weeks in the Gigli group. For the creation of a metaphyseal atrophic non-union in the osteoporotic bone, a piezoelectric saw should be used.

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