Does application time of alendronate sodium effect the spinal fusion in ovariectomized rats? [Alendronate sodyum uygulama zamani,ovariyektomi yapilmiş siçanlarda spinal füzyon üzerine etkili midir?]

Objectives: in this experimental study the effect of alendronate (aln) sodium on spinal fusion,that was given preoperatively or postoperatively,was compared both mechanically and histologically in ovariectomized rats. the research question was does application time of alendronate sodium effect the spinal fusion in ovariectomized rats?. materials and methods: fifty female wistar rats with a mean weight of 200 g and an average age of 12 weeks were ovariectomized according to the standard procedure. the rats were randomized into three groups nine weeks after ovariectomy. group 1: spinal arthrodesis and saline weekly for six weeks postoperatively; group 2: spinal arthrodesis and aln sodium 1 μgr/kg/week for six weeks postoperatively; group 3: aln sodium 1 μgr/kg/week for six weeks preoperatively,then one week later spinal arthrodesis was done. the rats were sacrificed six weeks after fusion surgery and their vertebrae were evaluated by manual palpation,mechanical testing machine and histomorphometric analysis. results: fusion rates obtained by manual palpation were 50%,17.6% and 55.5% in group 1,2 and 3,respectively (p>0.05). mean values of fusion tissues in mechanical evaluation were 498±20.7,481±23.7 and 480±26.2 (mpa) accordingly (p>0.05). compared with group 1,delayed endochondral ossification and more cartilage matrix among bone grafts were seen in group 2 and 3 in histological evaluation. conclusion: application time of the aln sodium didn't significantly affect the lumbar spinal fusion rates in ovariectomized rats. in histological evaluation,delayed endochondral ossification was seen in aln sodium-treated groups.