To the editor: It is well known that outgrovah of collateral sprouts is a natural process during regeneration of theperipheral nervous system. However, current knowledge about this phenomenon was that aberrant growth...To the editor: It is well known that outgrovah of collateral sprouts is a natural process during regeneration of theperipheral nervous system. However, current knowledge about this phenomenon was that aberrant growth of axonal sprouts may lead to the fbrmation of persistent neuromas,1.2 From our previous work3-5 verified effectively in clinical environment for nerve repairing and related experiments by small gap sleeve neurorrhaphy, we made a possible inference for peripheral nerve collateral regeneration and functional repairing; the hypothesis of using these collateral sprouts as an auto graft resource to recover the injured nerve.展开更多
Objective: To evaluate the effect of autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone cement on the repair of tibial plateau defect in rabbits. Methods: We used autograft bone...Objective: To evaluate the effect of autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone cement on the repair of tibial plateau defect in rabbits. Methods: We used autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone ce ment to repair tibial plateau defect in rabbits. Gross and histo logic observations, Xray examination, and biomechanical test were conducted at 1, 2, 4, 8 weeks after operation. Results: Xray examination found that the bone den sity was evidently reduced in calcium sulfate group at 8 weeks after operation; there were no marked changes in other groups. The maximal load measurements showed that autograft and allograft groups were greater than calcium sulfate and calcium phosphate groups at 1 and 2 weeks after operation. However at 4 and 8 weeks after operation, no significant difference was found among the four groups. In autograft and allograft groups, there was no significant difference in biomechanical intensity at 2, 4, and 8 weeks,but it was significantly higher than that at 1 week. In cal cium sulfate and calcium phosphate groups, the outcome was ranked in descending order as 1 week〈 2 week〈 4 week =8 week. Histologic examination found a great amount of new bones at 8 week in both autograft and allograft groups. In calcium sulfate group, calcium sulfate was almost absorbed and there were numerous bone trabeculations. There was a large amount of unabsorbed calcium phosphate in calcium phosphate group. Conclusion: At 12 weeks postoperatively, the biome chanical intensity is higher in autograft and allograft groups than calcium sulfate and calcium phosphate groups, but after 48 weeks, there is no significant difference among groups. At 12 weeks, the biomechanical intensity in all groups is increased, but at 48 weeks, there is no significant increase. The rates of absorption and bone formation are quicker in calcium sulfate group than calcium phosphate group.展开更多
文摘To the editor: It is well known that outgrovah of collateral sprouts is a natural process during regeneration of theperipheral nervous system. However, current knowledge about this phenomenon was that aberrant growth of axonal sprouts may lead to the fbrmation of persistent neuromas,1.2 From our previous work3-5 verified effectively in clinical environment for nerve repairing and related experiments by small gap sleeve neurorrhaphy, we made a possible inference for peripheral nerve collateral regeneration and functional repairing; the hypothesis of using these collateral sprouts as an auto graft resource to recover the injured nerve.
文摘Objective: To evaluate the effect of autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone cement on the repair of tibial plateau defect in rabbits. Methods: We used autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone ce ment to repair tibial plateau defect in rabbits. Gross and histo logic observations, Xray examination, and biomechanical test were conducted at 1, 2, 4, 8 weeks after operation. Results: Xray examination found that the bone den sity was evidently reduced in calcium sulfate group at 8 weeks after operation; there were no marked changes in other groups. The maximal load measurements showed that autograft and allograft groups were greater than calcium sulfate and calcium phosphate groups at 1 and 2 weeks after operation. However at 4 and 8 weeks after operation, no significant difference was found among the four groups. In autograft and allograft groups, there was no significant difference in biomechanical intensity at 2, 4, and 8 weeks,but it was significantly higher than that at 1 week. In cal cium sulfate and calcium phosphate groups, the outcome was ranked in descending order as 1 week〈 2 week〈 4 week =8 week. Histologic examination found a great amount of new bones at 8 week in both autograft and allograft groups. In calcium sulfate group, calcium sulfate was almost absorbed and there were numerous bone trabeculations. There was a large amount of unabsorbed calcium phosphate in calcium phosphate group. Conclusion: At 12 weeks postoperatively, the biome chanical intensity is higher in autograft and allograft groups than calcium sulfate and calcium phosphate groups, but after 48 weeks, there is no significant difference among groups. At 12 weeks, the biomechanical intensity in all groups is increased, but at 48 weeks, there is no significant increase. The rates of absorption and bone formation are quicker in calcium sulfate group than calcium phosphate group.