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1.
The behaviour of free periosteal and 200 micron thick osteoperiosteal grafts was studied histologically in 40 six-week-old rabbits. The grafts were taken from the tibia and fixed on either side of the same lumbar vertebra between the spinous and mamillary processes. The free stripped periosteum had better osteogenic activity than the 200 micron thick osteoperiosteum. The new bone was formed by the osteogenic cells of the cambium layer in both types of graft.  相似文献   

2.
《Acta orthopaedica》2013,84(1-6):197-204
The vascularization of free periosteal and 100 micron thick osteoperiosteal grafts was studied in growing rabbits. Sixteen rabbits with 32 periosteal and 32 osteoperiosteal grafts were operated upon and microangiographed 1–21 days postoperatively. the vascularization of free periosteal grafts started 1 day postoperatively and that of osteoperiosteal grafts 3 days postoperatively. the first capillaries seemed to enter through the cambium layer in periosteal grafts and through the cortex in osteoperiosteal grafts.  相似文献   

3.
The vascularization of free periosteal and 100 micron thick osteoperiosteal grafts was studied in growing rabbits. Sixteen rabbits with 32 periosteal and 32 osteoperiosteal grafts were operated upon and microangiographed 1-21 days postoperatively. the vascularization of free periosteal grafts started 1 day postoperatively and that of osteoperiosteal grafts 3 days postoperatively. the first capillaries seemed to enter through the cambium layer in periosteal grafts and through the cortex in osteoperiosteal grafts.  相似文献   

4.
The bone-forming capacity of free periosteum was compared with that of 100 micrometers thick osteoperiosteum and periosteum with full thickness cortex taken from the tibia of 6-week-old rabbits. Altogether 78 rabbits were operated on. The results revealed that the osteogenic capacity of free periosteum and 100 micrometers thick osteoperiosteum was about the same, and that osteoperiosteum with full thickness cortex was inferior in this regard.  相似文献   

5.
The quantity of new bone formed by revascularized periosteal grafts was compared with that formed by nonvascularized periosteal grafts in ulnar diaphyseal defects in dogs. Although in general the revascularized periosteal grafts produced a greater quantity of bone than their nonvascularized counterparts, this osteogenic behavior was not consistent. The results, however, are sufficiently encouraging to merit further investigation into the free transfer of revascularized periosteal autografts.  相似文献   

6.
Bone graft incorporation. Effects of osteogenic protein-1 and impaction   总被引:9,自引:0,他引:9  
Impaction of cancellous bone grafts in a bone chamber in rats in a previous study led to decreased ingrowth of new bone after 6 weeks compared with unimpacted grafts. The current study analyzes whether this decrease represented a final loss of ingrowth or just a delay, if the decrease was influenced by immunologic factors, and if it was possible to influence the inhibitory effect by adding a bone morphogenetic protein. Bone chambers with impacted or unimpacted bone grafts were implanted bilaterally in rat tibias. The mean bone ingrowth distance into the graft was measured on histologic sections. Three experiments were done: (1) the bone ingrowth into impacted and unimpacted grafts was studied at 6 and 12 weeks; (2) the immunologic influence was studied by comparing isogeneic grafts with allogeneic grafts; and (3) the authors tried to influence the decrease in bone ingrowth in impacted grafts by adding osteogenic protein-1. Bone ingrowth into the impacted graft was decreased at 6 weeks but not at 12 weeks. No difference was found between isografts and allografts at 6 weeks. With the addition of osteogenic protein-1, the impacted grafts showed dramatically increased bone ingrowth. Impacted bone grafts are incorporated at a slower rate than were structural grafts. The delay can be reversed by adding osteogenic protein-1, making ingrowth faster than in structural bone.  相似文献   

7.
《Acta orthopaedica》2013,84(1-6):29-35
The bone-forming capacity of free periosteum was compared with that of 100 urn thick osteoperiosteum and periosteum with full thickness cortex taken from the tibia of 6-week-old rabbits. Altogether 78 rabbits were operated on.

The results revealed that the osteogenic capacity of free periosteum and 100 μm thick osteoperiosteum was about the same, and that osteoperiosteum with full thickness cortex was inferior in this regard.  相似文献   

8.
The bone-forming capacity of free periosteum was compared with that of 100 urn thick osteoperiosteum and periosteum with full thickness cortex taken from the tibia of 6-week-old rabbits. Altogether 78 rabbits were operated on.

The results revealed that the osteogenic capacity of free periosteum and 100 μm thick osteoperiosteum was about the same, and that osteoperiosteum with full thickness cortex was inferior in this regard.  相似文献   

9.
The etiology of intimal hyperplasia in autogenous vein grafts used for arterial replacement was experimentally studied in dogs. We previously developed an experimental model, which mimicked a human extremity with poor run-off of peripheral arteries. This model characterized the abnormal flow by a weak fluctuation of wall shear stress at the site adjacent to the vessel wall. In this model we found that an autogenous vein implanted into the femoral artery under such abnormal flow conditions exhibited remarkable intimal thickening; 200-400 micron at 1 month and 300-500 micron at 6 months. A fluorescence microscopic study revealed that Evans blue-albumin complex entered the inner wall of vein grafts transplanted in abnormal flow conditions until about 2 weeks after implantation, after which further permeation was no longer observed. A similar observation was made in the fibrinogen distribution of subendothelial tissue. These results showed that abnormal flow conditions enhance the permeation of certain substances into immaturely repaired intimal tissues of autovein grafts. This phenomenon is thought to be responsible for the proliferation of smooth muscle cells, leading to hyperplasia of autovein grafts.  相似文献   

10.
After the chondrogenic potential of free grafts of perichondrium was shown in several experimental studies, perichondrium has been used to reconstruct cartilage tissue in various clinical situations. This study investigates the effects of human amniotic fluid on neochondrogenesis from free perichondrial grafts in a rabbit model. Since this fluid contains high concentrations of hyaluronic acid, hyaluronic acid-stimulating activator, growth factors, and extracellular matrix precursors during the second trimester, it may have a stimulating effect on neochondrogenesis. Perichondrial grafts, measuring 20 x 20 mm2 were obtained from the ears of 144 New Zealand young rabbits and were sutured over the paravertebral muscles. The rabbits were randomly divided into three groups with 48 rabbits per group. In group 1, 0.3 ml human amniotic fluid, and in group 2, 0.3 ml saline were injected underneath the perichondrial grafts. Group 3 formed the control group in which no treatment was given. Histologically, neochondrogenesis was evaluated in terms of cellular form and graft thickness at 2, 4, 6, and 8 weeks after surgery. In group 1, the mature cartilage was generated quickly and the cartilage plate in this group was significantly thick and extensive when compared with groups 2 and 3 at 8 weeks ( p<0.05 ANOVA). In conclusion, our study shows that human amniotic fluid enhances neochondrogenesis from free perichondrial grafts. The rich content of hyaluronic acid and growth factors possibly participate in this result.  相似文献   

11.
Allograft struts are used to reinforce the deficient proximal femur in hip arthroplasty or for fixation of a periprosthetic fracture. Although the use of strut grafts wired or cabled to the proximal femur generally has been successful, the time for healing is slow. The purpose of the current study was to determine whether cortical strut graft healing to the femur could be enhanced by the addition of recombinant human osteogenic protein-1. Fourteen adult dogs underwent bilateral onlay allograft strut procedures to the midfemur using stainless steel cables. In each animal one femur received 500 mg of osteogenic protein-1 device (2.5 mg recombinant human osteogenic protein-1/g Type I collagen) interposed between the graft and host bone. The results showed that the healing of cortical strut grafts to the femur was enhanced dramatically by the addition of the osteogenic protein-1 device. The sites treated with osteogenic protein-1 had significantly greater radiographic, histologic, and microradiographic scores at all times. Rapid formation of new bone and graft incorporation was observed in sites treated with the osteogenic protein-1 device. Strut healing with the osteogenic protein-1 device at 4 weeks postoperative was superior to the healing in control sites at 8 weeks. Improving and accelerating the course of cortical strut graft healing should provide a substantial clinical benefit in lowering the risk of graft nonunion and fracture and shorten the time of protected weightbearing and functional disability.  相似文献   

12.
目的:探讨厚中厚皮片游离移植治疗下肢慢性溃疡创面的临床效果。方法:2016年1月-2018年12月,收治20例下肢慢性溃疡创面患者,切除肉芽创面基底纤维板层后,进行厚中厚皮片游离移植修复手术。结果:17例患者皮片完全成活,2例患者皮片出现少量水疱,1例患者皮片出现局部感染、坏死。术后随访6~12个月,下肢外观及功能恢复良好。结论:去除肉芽创面基底纤维板层,应用厚中厚皮片游离移植修复下肢慢性溃疡创面,可获得良好临床效果。  相似文献   

13.
Synthetic arterial grafts fail because of thrombosis. Rapid endothelial coverage would be expected to generate a minimally thrombogenic surface and reduce the rate of failure. We investigated the possibility that such a lining could be established by transmural capillary ingrowth in polytetrafluoroethylene (30 or 60 micron internodal distance) and Dacron baboon aortoiliac grafts of 4 mm in diameter and 5 to 7 cm in length. All grafts demonstrated endothelial ingrowth from the cut edges of adjacent artery. The central portions of the 30 micron polytetrafluoroethylene grafts were still not healed at 3 months. Two of six Dacron grafts were healed 1 month postoperatively and all were healed at 3 months, whereas all 60 micron polytetrafluoroethylene grafts were healed 2 weeks postoperatively. At early follow-up, islands of endothelium were seen in the middle of the 60 micron polytetrafluoroethylene and Dacron grafts. These observations support the concept that transmural migration of capillaries can provide multiple sources of endothelium and early endothelial coverage of porous synthetic arterial grafts. This response is affected by the porosity and possibly the thrombogenicity of the graft material.  相似文献   

14.
This article describes the development of a polyetherurethane sheet embedded with powdered charcoal ( UPC ) for use in a hemoperfusion system. The UPC was 200 micron thick and the release of microparticles could be limited. The powdered charcoal used was selected for optimum pore size distribution and particle size (10-40 micron) to provide a maximum adsorption of bilirubin. The results of an in vitro adsorption test with this material showed an adsorption of bilirubin approximately 14 and 6 times higher than those by bead-type charcoal and XAD-7, respectively. Jaundiced dogs were subjected to direct hemoperfusion through a UPC column containing 36 g powdered charcoal. Effective decreases in bilirubin were observed, giving the maximum removal amounts of 78% in conjugated bilirubin and 76% in unconjugated bilirubin.  相似文献   

15.
For evaluating whether 2 types of expanded polytetrafluoroethylene, ringed E-PTFE graft can be utilized for venous reconstruction, especially, for superior vena caval reconstruction or not, the ringed E-PTFE grafts which had 10-15 micron fibril length and 30 micron fibril length were implanted between the innominate vein and the right atrium of the 20 dogs. The grafts were removed for histological and scanning electromicroscopic evaluation at intervals varying from one to twelve postoperative months. Overall patency rate was 62% and severe stenosis at the site of anastomosis was seen in 2 grafts. More than half of the graft showed mild to moderate intimal hyperplasia at the anastomotic sites and the early stage of thrombosis at the middle of the grafts. Mesenchymal cell infiltration was occurred in 46% of the grafts.  相似文献   

16.
In this experimental study with bone defects, we focussed on the one hand on external and internal osteogenic callus formation after filling the defect and on the other on the osteochondrogenic differentiation capacity of 4-day-old fibrous-like callus grafts and 12-day-old woven bone grafts in an osteogenic environment. A standard cortical bone defect of the femur was created in 95 young rats. The defect was filled with a cortical bone graft and 4- and 12-day-old callus grafts. The grafts were transplanted as such or in Nucleopore chambers. Follow-up was done at 1, 2, 3 and 6 weeks. The osteochondrogenic tissue formed was studied histologically and histomorphometrically. The results suggest that the filling of the bone defect had no influence on the primary external and internal osteogenic callus formation at 1 and 2 weeks. At 3 and 6 weeks in the chamber groups the persisting internal bridging woven bone was converted into more compact lamellar bone whereas periosteal callus remained at the edges of the defect. In the other groups at 3 and 6 weeks the normal shape of the cortex was reconstituting. Four-day-old fibrous-like callus formed bone in the Nucleopore chamber, indicating that fibrous-like callus tissue at 4 days contains osteogenic cells. Twelve-day-old callus consisting of woven bone was partially differentiated to cartilage, showing that woven bone contains cells capable of chondrogenic differentiation.  相似文献   

17.
This prospective study measured the patellar tendon thickness of 543 patients who underwent anterior cruciate ligament (ACL) reconstruction with an autogenous bone-patellar tendon-bone graft to document the normal range of patellar tendon thickness and to determine if using thicker than normal patellar tendons as an ACL graft source affected postoperative outcome. The postoperative results of 55 patients who underwent ACL reconstruction with a patellar tendon > or =7 mm thick (thick tendon group) were compared with those of 488 patients who underwent ACL reconstruction with a patellar tendon < or =6 mm thick (normal tendon group). 5 mm (4.5 mm in women and 5.3 mm in men) with a range of 3-11 mm (3-7 mm in women and 3-11 mm in men). There was no statistically significant difference in the postoperative KT-1000 arthrometer mean manual maximum difference (2.0 mm for grafts < or =6 mm thick and 1.9 mm for grafts > or =7 mm thick), postoperative quadriceps muscle strength scores, modified Noyes questionnaire subjective scores (mean of 91 points for grafts < or =6 mm thick and 92 points for grafts > or =7 mm thick), or postoperative stability and pain scores. These results indicate that an abnormally thick patellar tendon should not preclude the use of this involved tendon as a graft source for ACL reconstruction.  相似文献   

18.
The purpose of this study was to compare the chondrogenic potential of free perichondrial with free periosteal grafts in the resurfacing of full-thickness defects of patellar articular cartilage in rabbits. We used adolescent New Zealand rabbits weighing between 2.4 and 3.6 kg. A 6-mm wide and 3-mm thick defect was created on the patellar articular surface. A total of 30 rabbits were randomly divided into a control group and two test groups. One test group received free perichondrial grafts (PC); the other received free periosteal grafts (PO). All the animals were killed 8 weeks after surgery. All the histological samples were scored from 0 to 17 according to a standard scoring system. Differences in the quality of the regenerated tissue were only found between the control and the test groups. There were no statistically significant histological differences between the grafted defects of the PC and the PO groups that there are not on any of the variables. The results of this study support that there are not significant differences in the quality of the repair tissue when using these two types of biological grafts. Received: 7 July 1998 / Accepted: 8 January 1999  相似文献   

19.
Four groups of piglets were used to test the use of pericardium and periosteum as free grafts in the repair of full thickness cervical tracheal defects. Pericardium provided an airtight, rapidly healing graft, but did not give sufficient structural rigidity to prevent narrowing and growth failure at the graft site. Composite grafts of pericardium and periosteum were also unsatisfactory, in that the periosteum failed to produce enough bone to prevent collapse of the graft. Since previous studies have shown that periosteal grafts result in good bone formation when applied alone or as an extramucosal support, it is concluded that the osteogenic potential is dependent on the available blood supply and speed of revascularization. It appears that the presence of pericardium in the composite grafts may have inhibited this property.  相似文献   

20.
BACKGROUND: Periosteum is an osteogenic, flexible tissue. This study investigated the osteogenic potential of vascularized periosteal flaps in heterotopic conditions and compared it to the neo-osteogenesis from vascularized periosteal flaps combined with bone grafts with different properties (autologous and xenograft). METHODS: Vascularized periosteal flaps from the hindlimbs of 48 rabbits formed cylindrical pouches that were buried in muscles. The pouches were filled with autologous bone grafts (P/A group, n = 16), xenograft (P/X group, n = 16), or left empty (P/E group, n = 16). Specimens were harvested between 1 and 4 months and underwent radiographic, histologic, and histomorphometric evaluation. RESULTS: The total surface area was larger in the groups combined with bone grafts. Osseous apposition did not differ significantly in the P/A and P/X groups (p > 0.05). The central cavity contained hematopoietic cells (P/A), xenograft (P/X), or was absent (P/E). CONCLUSION: Vascularized periosteal flaps presented strong osteogenic capacity in heterotopic conditions. Combination with bone grafts resulted in larger specimens. The quality of neo-osteogenesis was not influenced by the different properties of combined bone grafts.  相似文献   

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