RESUMO
Objective To investigate the repairing effect of transplantation of allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft to bone defect. Methods Twenty Long-eared white male rabbits were chosen as experimental model of bilateral 12 mm combined bony and periosteal radial defect. Cryopreserved allograft periosteum with allogeneic fetal bone were implanted in the left defect as experimental side and fetal bone was simply transplanted in the right defect as control side. Bone repair process in the two groups were compared by macroscopy, microscopy, roentgenograms and the contents of calcium and phosphate in the defect area at 2、4、8 and 12 weeks after transplantation. Results There was significant statistic difference in the contents of calcium and phosphate between the experimental and control sides at 4、8 and 12 weeks after transplantation (P<0.05). With time passing by, the contents of calcium and phosphate have the increasing trends. In the experimental group, lamella bone was seen and medullary canal recanalized at 8 weeks postoperatively. The histological section showed the bone lacuna and lamella bone were formed. Conclusion It suggests that allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft can promote bone repair, and allogeneic fetal bone is excellent bone substitute.
RESUMO
Objective To explore the effects of different types of passive and active movements of foot and ankle on the venous return in the lower limb in order to provide evidence for prevention of venous stasis and deep- vein thrombosis(DVT)after joint replacement. Methods Peak and average velocities of the femoral vein were detected and measured by using color ultrasound Doppler on 30 limbs in 15 healthy volunteers under the circumstance of resting and different types of passive and active movements of foot and ankle. Results During the passive movements of the flexion and extension, inversion and eversion, and the circumduction of foot and ankle, the flexion and extension as well as the inversion and eversion only slightly increased the velocities of venous blood flow. The circumduction produced a higher increase in venous blood flow than the former two movements, increasing the peak velocity by 31.3％ and average velocity by 33.9％ . In the same 3 types of the active movements of foot and ankle, the active flexion and extension, inversion and eversion resulted in increases in peak velocity of 41.3％ and 32.9％ and in average velocity of 40.1％ and 32.4％ , respectively. The active circumduction of foot and ankle produced the strongest influence on the promotion of venous blood flow with the peak velocity increased by 69.3％ and average velocity by 69.1％ . Conclusion The active circumduction, flexion and extension, inversion and eversion, and the passive circumduction of foot and ankle can be utilized to prevent DVT after joint replacement. The active circumduction of foot and ankle is the optimal exercise to prevent DVT.