RESUMO
A distal femoral osteotomy in 46 rabbits was fixed either with biodegradable polydioxanone (PDS) thread and pins (group A, 31 animals) or with metallic Kirschner wire and pins (group B, 15 animals). Postoperatively, the distal part of each femur was removed and evaluated, and bone sections were evaluated by histology and histomorphometry. Macroscopic studies showed complete PDS absorption in all cases 24 weeks postoperatively. The histologic studies revealed new bone surrounding the area of the implant 3 weeks postoperatively, and at 24 weeks postoperatively, there was thinning or disappearance of the new bone around the implant. On the basis of the present study, PDS thread and pins show promise for the fixation of osteotomies or fractures of cancellous metaphyses of small long bones, such as metacarpals and phalanges.
Assuntos
Fêmur/cirurgia , Consolidação da Fratura , Polidioxanona/uso terapêutico , Animais , Pinos Ortopédicos , Fios Ortopédicos , Feminino , Fraturas do Fêmur/cirurgia , Fêmur/patologia , Técnicas Histológicas , Masculino , Osteogênese , Osteotomia , Coelhos , SuturasRESUMO
30 adult male New Zealand white rabbits underwent osteotomy and plate fixation of the left ulna for 6 or 12 weeks. The right ulna served as control. In half of the rabbits 6 IU calcitonin was given daily until death, and in the other half placebo injections in the same manner. A three-point bending test was performed on both ulnae. Sections of bone, covered or uncovered by the plates, were examined histologically. Long-term administration of calcitonin increased the mechanical properties of both fractured and intact bones and reduced porosity of the cortex under the plate.
