Objective To study the vascularization of the compositeof bone morphogenetic protein 2 (BMP-2) gene transfected marrow mesenchymal stem cells (MSCs) and biodegradable scaffolds in repairing bone defect. Methods Adenovirus vector carrying BMP-2 (Ad-BMP-2) gene transfected MSCs and gene modified tissue engineered bone was constructed. The 1.5 cm radial defect models were made on 60 rabbits, which were evenly divided into 4 groups randomly(n=15, 30 sides). Different materials were used in 4 groups: Ad-BMP-2 transfected MSCs plus PLA/PCL (group A), AdLacz transfected MSCs plus PLA/PCL (group B), MSCs plus PLA/PCL (group C) and only PLA/PCL scaffolds (group D). The X-ray, capillary vessel ink infusion, histology, TEM, VEGF expression and microvacular density counting(MVD) were made 4, 8, and 12 weeks after operation. Results In group A after 4 weeks, foliated formed bones image was observed in the transplanted bones, new vessels grew into the bones, the pores of scaffolds were filled with cartilage callus, osteoblasts with active function grew around the microvessels, and VEGF expression and the number of microvessels were significantly superior to those of other groups, showing statistically significant difference (Plt;0.01); after 8 weeks, increasingly more new bones grew in the transplanted bones, microvessels distended and connected with each other, cartilage callus changed into trabecular bones; after 12 weeks, lamellar bone became successive, marrow cavity recanalized, microvessels showed orderly longitudinal arrangement. In groups B and C, the capability of bone formation was weak, the regeneration of blood vessels was slow, after 12 weeks, defects were mostly repaired, microvessels grew among the new trabecular bones. In group D, few new vessels were observed at each time, after 12 weeks, broken ends became hardened, the defectedarea was filled with fibrous tissue. Conclusion BMP-2 gene therapy, by -upregulating VEGF expression, indirectly induces vascularization ofgrafts,promotes the living of seed cells, and thus accelerates new bone formation.
OBJECTIVE: To investigate the ability of repairing bone defect with the compound of coralline hydroxyapatite porous (CHAP), fibrin sealant(FS) and staphylococcus aureus injection (SAI), and the feasibility to use the compounds as bone substitute material. METHODS: The animal model of bone defect was made on the bilateral radius of 54 New Zealand white rabbits, which were randomly divided into the experimental group(the defect was repaired with CHAP-FS-SAI), control group(with autograft) and blank control group(the defect was left unrepaired) with 18 rabbits in each group. The ability of bone defect repair was evaluated by gross observation, histopathological study, X-ray and biomechanical analysis 2, 4, 8 and 12 weeks after repair. RESULTS: (1) In the 2nd week, tight fibro-connection could be found between the implant and fracture site and there were many fibroblasts and capillary proliferation with many chondrocytes around CHAP in the experimental group, while only a few callus formed, and chondrocytes, osteoblast and osteoclast existed in the control group. (2) In experimental group and control group, a large quantity of callus was found 4 and 8 weeks; ossification of chondrocytes with weave bone formation were found 4 weeks and many osteocytes and weave bones and laminar bones were found 8 weeks. (3) In the 12th week, the complete ossification of implant with well bone remodeling, a large number of mature osteocytes and laminar were found in experimental group and control group, and CHAP still existed in the experimental group; the defect area filled with fibro-scar tissue and only many fibroblasts could be seen in blank control group. (4) X-ray findings were the following: In experimental and control groups, callus formation could be seen 2 weeks postoperatively, more callus formed 4 weeks, the bone defect area disappeared and CHAP scattered in the callus 8 weeks; the fracture line disappeared and medullary cavity became united (in control group); and in the 12th week, the cortex became continuous, the medullary cavity became united, and remodeling completed, while bone defect was not still united in blank control group. The maximal torque and torsional stiffness in the experimental group is higher than those in the control group 2 weeks (P lt; 0.05), but there was no significant difference (P gt; 0.05) between the two groups 4, 8, 12 weeks after repair. CONCLUSION: The compound of CHAP-FS-SAI has good biological compatibility, and it can be used for one kind of bone substitute material to repair the bone defect.
Objective To evaluate the clinical effects of fibula flap grafts on the repair of the extremities with traumatic compound tissue defects. Methods In 12 cases, the fibula flap grafts were employed to restore the extremities with traumatic compound tissue defects. Of the 12 patients, 9 were males, 3 were females; their ages ranged from 12 to 45. There were 2 cases of tibia defect combined with fibula fracture, 2 cases of tibia defect, 2 cases of radius defect, 3 cases of ulna defect, 1 case of calcaneus defect,and 2 cases of firstmetatarsus defect. The bone defect length ranged from 4.2 to 10.6 cm, 7.8 cm in average.The skin defect area ranged from 10.0 cm×4.5 cm to 27.0 cm×15.0 cm. The free transplantation of fibular flaps were used in 9 cases, the lapse operation were used in 2 cases, retrograde shift were used in 1 case. Results Postoperational vein crisis and commonperoneal nerve traction injury were observed in category mentioned above respectively. All the 12 fibula flaps survived after proper treatments such as removalof great saphenous vein. Follow-ups were done for 6 to 24 months. Both the transferred fibula and the recipient broken end reflected bones were healed. Four patients underwent the second-phase reconstruction operation oftendon moving power. One wrist and 1 ankle underwent arthrodesis in 3 to 6 months.All the effects were satisfactory. Conclusion The fibula flap grafts provide arelatively better alternative to repair the extremities with long bone compoundtissue defects. In addition, the sensory function reconstruction of fibula flaps should be given full attention.
OBJECTIVE To investigate a good method for repairing the long bone defect of tibia combined with soft tissue defect. METHODS From 1988-1998, sixteen patients with long bone defect of tibia were admitted. There were 12 males, 4 females and aged from 16 to 45 years. The length of tibia defect ranged from 7 cm to 12 cm, the area of soft tissue defect ranged from 5 cm x 3 cm to 12 cm x 6 cm. Free fibula grafting was adopted in repairing. During operation, the two ends of fibular artery were anastomosised with the anterior tibial artery of the recipient, and the composited fibular flap were transplanted. RESULTS All grafted fibula unioned and the flap survived completely. Followed up for 6 to 111 months, 14 patients acquired the normal function while the other 2 patients received arthrodesis of the tibial-talus joint. In all the 16 patients, the unstable ankle joint could not be observed. CONCLUSION The modified method is characterized by the clear anatomy, the less blood loss and the reduced operation time. Meanwhile, the blood supply of the grafted fibula can be monitored.
In the study of repair of massive bone defect with free vascularized fibula graft, 13 cases were reported, in which traumatic defect in 7 cases, segmental resection of bone from tumors in 5 cases and osteomylitis in 1 cases. They all were treated successfully with vascularized fibular graft. After a follow-up of 6 months to 7 year, bone healing was observed with satisfactory and rehabilitation of functions. In one case, fatigued fracture occured twice due to early walking. It was concluded that free vascularized fibular graft was very helpful in the repair of massive bone defect, but prolonged external fixation after operation might be important to prevent fractur of grafted bone.
The treatmen t of the bone defect of the distal part of the radiu s included repair of the bone defect and resto rat ion of the funct ion of the w rist jo in t. Since 1979, th ree operat ive methods w ere u sed to t reat 13 cases, and they w ere graf t ing of the vascu larized f ibu la by anastom rsis f ibu lar vessels, graf t ing of upper part of f ibu lar w ith lateral inferio rgen icu lar artery and graf t ing vascu larized scapu la f lap. Follow up had been carried ou t from1 to 10 years. The resu lt w as sat isfacto ry. The discu ssion included the repair of the defect of the m iddle o r distal part of the radiu s, the operat ive methods, main at ten t ion s and indications. It was considered that it shou ld be based on the length of bone defect wh ile the operative method was considered.
Objective To investigate the effect of anti-infective reconstitutedbone xenograft (ARBX) as primary grafting on repair of a segmental contaminateddefect in canine radius. Methods The contaminated segmentaldefects of 1.5 cm were made in both radius of 8 canine and 1 ml of staphylococal suspension was injected into the defect region at a concentration of 5×106 CFU/ml. ARBX(experimental side) or RBX(control side) was implanted into the two sides of the defects respectively as primary grafting followed by internal fixation. The results were compared between the two grafting materials in repairing the contaminated segmental defect. Results In ARBX side, the defects were repaired completely in 5 cases and partially in 1 case, and there existed no osteomyelitis in all cases; while in RBX side, the defects were repaired partially in 1 case and were not repaired in 5 cases after 6 months of operation, and there existed osteomyelitis in all cases. Conclusion Besides its b osteoinductive and osteoconductive activity, ARBX is highly antibacterial and can be used as primary grafting in repairing contaminated segmental defects.
Objective To study the effect of autogenous bone marrow on guided bone regeneration (GBR),and evaluate the repairing ability of GBR in bone defect with autogenous bone marrow. Methods Ten mm segmental defects were produced in both radii of 18 rabbits. The defect was bridged with a silicon tube. Autogenous bone marrow was injected into the tube on the experimental group at 0, 2,4 weeks after operation, and peripheralblood into the control group at thesame time. The X-ray, gross, histological and biochemical examinations were observed invarious times. Results The new bone formation of experimental group was prior to that of control group; calcium and alkaline phosphatase of experimental groupwere higher than those of control group. The experimental group had all been healed at the tenth week, but no one healed in control group. Conclusion It can be conclude that autogenous bone marrow can stimulate bone formation and facilitate GBR in bone defect.
OBJECTIVE: To study the effect of self-setting calcium phosphate cement (CPC) on the repair of local bone defects after resection of cyst in children. METHODS: From December 1998 to May 2002, 22 patients with bone defects were repaired with CPC. Their ages ranged from 4 to 10 years with an average of 8.3 years. There were 11 cases of non-ossifying fibroma, 7 cases of osteoid osteoma, 2 cases of bone cyst and 2 cases of fibrous dysplasia. The bone defects are located as the following: femur in 14 cases, tibia in 6 cases and humerus in 2 cases. CPC spongiosa granules were filled in 11 cases, injectable CPC were filled in 2 bone cyst cases. The patients were followed up for 5-48 months, averaged 23.5 months. RESULTS: Bone matrix grew well and no recurrence was found. CONCLUSION: The method with simple CPC in repairing bone defects is safe, non-toxic, economic and convenient in children.
From June, 1965 through August, 1994, 260 cases of large bone defects were repaired by preserved bones. The donor bones were obatined from the long bones of the amputated limbs from trauma and the bones, such as the femoral head, patella, ribs, etc. removed from operations. The donor bones were preserved in 0.1 per cent merthiolate or 75 per cent alcohol and were stored at 4 degrees centigrade. Two patients had bad reactions which, however, did not influence the consolidationof the bone grafts. The patients were followed up for an average of 4 years and5 months, and all the bone grafts had solid consolidation with the host bones. There was no recurrence in the tumor patients.