ABSTRACT
Objective To compare 2 kinds of artificial dermis Lando(R) versus Pelnac(R) combined with induced membrane technique in the treatment of composite trauma in rabbit bilateral femurs.Methods Twenty-seven male rabbits,weighing from 1.92 kg to 2.21 kg (average,2.04 kg),were used in the experiments.After models of composite trauma were created in the bilateral femurs of all the rabbits,the bilateral femurs of 9 random rabbits were subjected to the treatment of artificial dermis Lando(R) plus induced membrane (Lando(R) group),the bilateral femurs of another 9 random rabbits to the treatment of artificial dermis Pelnac(R) plus induced membrane (Pelnac(R) group),the left femur of the remaining 9 rabbits to the treatment of induced membrane (control group) and the right femur of the remaining 9 rabbits to no treatment (sham operation group).Three rabbits from each group (the same for the control and sham operation groups) were randomly sacrificed at 2,4 and 6 weeks after operation.Samples from the operation sites were taken for gross observation of the induced membrane and observation of the microstructure of the membrane by conventional hematoxylin-eosin staining.In addition,the microvessel density (MVD) was counted under microscopy taking CD34 immunohistochemistry as the standard.The data were statistically analyzed.Results The collagen sponge layer was completely degraded 2 weeks after operation in the Lando(R) group but not in the Pelnac(R) group.The MVD [(0.90 ± 0.55)/HPF] in the Lando(R) group was significantly greater than that in the Pelnac(R) group [(0.28 ± 0.13)/HPF] (P ＜ 0.05).The collagen sponge layer was degraded 4 weeks after operation in the Lando(R) and Pelnac(R) groups and there was no significant difference between the 2 groups in MVD [(3.61 ± 1.31)/HPF versus (4.34 ± 0.77)/HPF] (P ＞ 0.05).At 6 weeks postoperatively,the MVD [(4.97 ±0.76)/HPF] in the Lando(R) group was significantly smaller than that in the Pelnac(R) group [(7.06 ± 1.03)/HPF] (P ＜ 0.05).At 2 weeks after operation,the MVD was (0.11 ±0.19)/HPF in the control group and the sham operation group,showing a significant difference compared with the Lando(R) group (P ＜ 0.05) but no significant difference compared with the Pelnac(R) group (P ＞ 0.05).The MVD at 4 and 6 weeks after operation in the control and the sham operation groups were all significantly different from those in the Lando(R) and the Pelnac(R) groups (P ＜ 0.05).Conclusions In the treatment of composite trauma in rabbits,the 2 kinds of artificial dermis combined with the induction membrane technique can lead to formation of induced membrane structure,providing a new alternative treatment for patients with bone and soft tissue defects caused by various causes in the clinic.The Lando(R) artificial dermis may accelerate the vascularization of induced membrane at 2 weeks while the Pelnac(R) may accelerate the vaseularization at 4 and 6 weeks.