Calcified Tissue International

, Volume 81, Issue 3, pp 232–239

Sequential Treatment with Intermittent Low-Dose Human Parathyroid Hormone (1-34) and Bisphosphonate Enhances Large-Size Skeletal Reconstruction by Vascularized Bone Transplantation

Authors

  • Takahiro Hashimoto
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
  • Mitsunori Shigetomi
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
  • Teruyasu Ohno
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
  • Tsunemitsu Matsunaga
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
  • Keiichi Muramatsu
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
  • Hiroshi Tanaka
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
    • Department of Veterinary Basic SciencesThe Royal Veterinary College, University of London
  • Toshihiko Taguchi
    • Department of Orthopedic SurgeryYamaguchi University School of Medicine
Article

DOI: 10.1007/s00223-007-9056-7

Cite this article as:
Hashimoto, T., Shigetomi, M., Ohno, T. et al. Calcif Tissue Int (2007) 81: 232. doi:10.1007/s00223-007-9056-7

Abstract

Vascularized bone transplantation enables reconstruction of large skeletal defects, but this process needs a long time. Since short-term intermittent parathyroid hormone (PTH) enhances rat fracture healing, we investigated the effects of 4-week intermittent low-dose (10 μg/kg/day) or high-dose (100 μg/kg/day) PTH followed by 4-week vehicle, low-dose or high-dose intermittent PTH, or zoledronic acid (ZOL, 2 μg/kg/week), a potent bisphosphonate, on large skeletal reconstruction by vascularized tibial grafting in rats. Compared to 8-week vehicle, 8-week low-dose PTH did not significantly increase the serum osteocalcin level as well as the urinary deoxypyridinoline level, while 4-week low-dose or high-dose PTH followed by 4-week ZOL decreased both of these levels. Eight-week PTH increased the bone mass of the graft and strength of the reconstructed skeleton in a dose-dependent manner; notably, the reconstructed skeleton showed an obviously higher response to PTH compared to the contralateral nonoperated femur. In contrast, 4-week PTH followed by 4-week vehicle reduced these effects and caused local bone loss at the host-graft junctions. Four-week PTH followed by 4-week ZOL did not induce such bone loss; however, 4-week high-dose PTH followed by 4-week ZOL caused a large callus in the distal cortical junction. Four-week PTH followed by 4-week ZOL increased the bone mass and strength similarly to 8-week PTH. These preliminary findings suggest, for the first time, that sequential treatment with short-term intermittent low-dose PTH and bisphosphonate as well as long-term intermittent low-dose PTH treatment enhance large skeletal reconstruction by vascularized bone transplantation, though early timing of sequential antiresorptive treatment could result in delay of bone repair.

Keywords

Skeletal reconstructionVascularized bone transplantationParathyroid hormoneBisphosphonateSequential treatment

Copyright information

© Springer Science+Business Media, LLC 2007