title: TOMOGRAFIC AND TENSIOMETRIC ASSESSMENT ON FEMURS FROM OOPHORECTOMIZED RATS SUBJECTED TO HORMONE REPLACEMENT THERAPY.
abstract: OBJECTIVE
  To analyze the biomechanical and tomographic effects of hormone replacement therapy (HRT) on femurs from rats subjected to induced menopause.
  
  
  METHODS
  Forty-five adult Wistar rats were divided equally into three groups. The first and second groups consisted of rats subjected to oophorectomy, and the third was the control group, consisting of nonoophorectomized rates. After verifying that hormone failure had occurred (exfoliative cytological test), only the first group received HRT, over a two-month period. After this period, the femurs were disarticulated and subjected to biomechanical tests in a universal testing machine to evaluate their strength, and were subjected to tomographic evaluation to determine the bone mineral density.
  
  
  RESULTS
  The exfoliative cytological test showed that hormone failure was induced in all the oophorectomized animals. A significant difference (p = 0.030) in maximum strength measurements was observed between the groups (higher in the group with HRT). Greater bone fragility was observed in the oophorectomized animals without HRT than in those with HRT (p = 0.010), in relation to the control group (p = 0.0107). There was greater bone strength in the oophorectomized rats with HRT than in those without HRT, and these values were similar to those of the control group (p = 0.179). In the tomographic evaluation, no significant differences were found between the groups (p = 0.625).
  
  
  CONCLUSIONS
  A significant increase in bone strength was observed with the use of HRT. However, treatment with HRT did not show any significant change in bone mineral density.
authors.affiliation: MSc student in the Postgraduate Clinical and Surgical Medicine Program, PUCPR.
authors.forename: Fábio Alexandre
authors.initials: FA
authors.lastname: Martynetz
authors.affiliation: PhD in Experimental Surgery from Unifesp. Titular Professor of Research Methodology at PUCPR and Adjunct Professor IV in the Department of Surgery, Federal University of Paraná
authors.forename: Maria de Lourdes
authors.initials: Mde L
authors.lastname: Pessole Biondo-Simões
authors.affiliation: Resident in Orthopedics and Traumatology, Cajuru University Hospital, PUCPR.
authors.forename: Juliano Rodrigo
authors.initials: JR
authors.lastname: Martynetz
authors.affiliation: Ophthalmologist from Pontificia Universidade Católica, Paraná
authors.forename: Tatiana Daher
authors.initials: TD
authors.lastname: Martynetz
authors.affiliation: Otorhinolaryngologist from Pontificia Universidade Católica, Paraná
authors.forename: Elise
authors.initials: E
authors.lastname: Zimerman
authors.affiliation: Neuroradiologist at X-leme. Radiologist in the Imaging Services of Cajuru University Hospital and Santa Casa de Misericórdia, Curitiba (PUCPR).
authors.forename: Heraldo Mello
authors.initials: HM
authors.lastname: Neto
keywords: Bone and bones; Femur; Hormone replacement therapy; Menopause; Osteoporosis; Rats; Tomography