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.
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 ability of the biodegradable polycaprolactone (PCL) material to repair bone defect and to evaluate the feasibility ofusing the PCL as the scaffold in tissue engineering bone. Methods The bone defect models of 4.5 mm×12 mm were made in the bilateral femoral condyle of 65 NewZealand white rabbits. The PCL cylinder was implanted into the right side of defect(experimental group, n=60), the high dense crystality hydroxyapatite was implanted into the left side of defect (control group, n=60), and the incision was sutured without any implants (blank group, n=5). The samples were harvested and observed by examinations of gross, X-ray, bone density,99mTc-MDP bone scanning, γ-display ratio and scanning electron microscope (SEM) after 3, 6, 9 and 12 months of operation. The results were compared between the experimental group and control group. Results At 3, 6, 9 and 12 months after operation, the gross and X-ray examinations indicated that the bone defect filled with the new bone onthe PCL-tissue surface, and no delayed inflammatory reaction appeared. The average bone mineral density was greater in the experimental group than that in the control group, and the difference had statistical significance(P＜0.05). Theresults of 99mTc-MDP bone scanning and γ-display ratio showed that thenuclide uptake was more in the PCL group than that in the control group. The SEM result proved that the new compact bone formed on the PCL migrating surface as the PCL degraded gradually，but the collagen fiber sheathe formed around the hydroxyapatitein the control group. Conclusion PCL possesses good biocompatibility and high bone inductive potentiality, it can be used to repair bone defect.
To observe the collagen-hydroxylaptite composite in the repair of bone defect, ten minipigs were chosen to make a mandibular dafect measuring 2 cm in diameter and the composite was implanted, while the use of autogenous bone graft and the blank wese served as control. On the 4, 8, 12, 24 and 48 weeks after the operation, the animals were sacrificed and the samples were examined under light microscope. The result showed that: no infection or necrosis occurred. The composite coalesced with host bone and the outcome was similar to that of the autogenous bone graft. No foreign body giant cells or vacuum left from osteonecrosis was observed. It was suggested that the composite had the advantage of abundant supply, easy to handle and no harm. The biocompatibility was good and might be hopeful as a bone substitute.
Objective To discuss the advantages and disadvantages of flaps in therepairment of soft tissue defects in upper extremity. Methods Based on the 2 609 cases of flaps in 2 512 patients from 1995 to 2004,the advantages and disadvantages of different sort of flaps, outcomes of treatment and indications of different soft of flaps were analyzed retrospectively. In the series, 2 089 pieces of the traditional flaps of different sorts were applied in 1 992 patients, 474 piecesof the axial flaps of different sorts were applied in 474 patients, different sorts of free flaps were used in 46 patients. Results Follow-ups were done for 1 month to 9 years (2.7 months in average). 2 531 flaps survived (97.01%); complete necrosis occurred in 10 flaps(0.38%); partial necrosis occurred in 68 flaps(2.61%). Of the 2 089 traditional flaps, 46 had partial necrosis(2.2%); 687 needed flap revisions(32.9%). Of the 474 axial flaps, 28 had complete or partial necrosis(5.9%); 82 needed revisions(17.3%). Of the 46 free flaps, 4 had complete or partial necrosis(8.7%) and nearly all the anterolateral flpas of thighs needed revisions.Conclusion Traditional flaps had the advantages of easy manipulation and the highest survival rate, however, also had the disadvantages of poor texture and many timesof operations. The flap with a pedicle had the advantage of good texture, consistent artery, free-range arc, however, the venous congestion was its disadvantage, which impaired the survival of the reverse flap. Free flap had the advantage ofgood texture and abandant donor site, but complicate manipulation was its shortage. Axial Flap with a pedicle is the optional choicefor repairing soft tissue defects in upper extremity.
Objective To study the vascularization of the compositeof bio-derived bone and marrow stromal stem cells(MSCs) in repairing goat tibial shaft defect.Methods Bio-derived bone was processed as scaffold material. MSCs were harvested and cultured in vitro. The multiplied and induced cells were seeded onto the scaffold to construct tissue engineered bone. A 20 mm segmental bone defect inlength was made in the middle of the tibia shaft in 20 mature goats and fixed with plate. The right tibia defect was repaired by tissue engineered bone (experimental side), and the left one was repaired by scaffold material (control side).The vascularization and osteogenesis of the implants were evaluated by transparent thick slide, image analysis of the vessels, and histology with Chinese ink perfusion 2, 4, 6, and 8 weeks after operation.Results More new vessels were found in control side than in experimental side 2 and 4 weeks after implantation (Plt;0.05). After 8 weeks, there was no significant difference in number of vessels between two sides(Pgt;0.05), and the implants were vascularized completely. New bone tissue was formed gradually as the time and the scaffold material degraded quickly after 6 and 8 weeks in the experimental side. However, no new bone tissue was formed andthe scaffold degraded slowly in control side 8 weeks after operation.Conclusion Bio-derived bone has good quality of vascularization. The ability of tissue-engineered bone to repair bone defect is better than that of bio-derived bone alone.
The causes of development of 56 cases of bone defects from firearm injuries of extremities were analyzed, and the advantages of transfer of vascularized iliac bone graft with deep iliac circumflex vessels in 28 cases and the indications of transfer of vascularked fibular bone graft with fibular vessel in 15 cases and the exporiences in 9 cases from the methed of transter of seapula-cutaneous composite graft were summarized. It was emphatically pointed out that the half-circle typo externa fixators had its unique advantages in the treatment of the bone defects of long bones of extremities from firearm injuries. It would enentually become the method of priority for the treatment of fractures, nonunion of fractures and bone defects of extremities from firearm injuries.
To evaluate the effect of 5-fluorouracil (5-FU) appl ied topically on preventing adhesion andpromoting functional recovery after tendon repair. Methods From August 2003 to June 2007, 48 patients with flexor tendonrupture of the fingers by sharp instrument were treated and randomly divided into two groups. In 5-FU group, 39 fingers of 26 patients included 17 males and 9 females, aged (29.3 ± 9.8) years; the locations were zone I in 19 fingers and zone II in 20 fingers; single finger was involved in 12 cases and more than 2 fingers were involved in 14 cases; and the time from injury to operation was (2.4 ± 1.6) hours. In control group, 36 fingers of 22 patients included 14 males and 8 females; aged (26.1 ± 8.7) years; the locations were zone I in 16 fingers and zone II in 20 fingers; single finger was involved in 10 cases and more than 2 fingers were involved in 12 cases; and the time from injury to operation was (2.1 ± 1.8) hours. No statistically significant difference was found in constituent ratio of age, gender, injured fingers and their zones, between two groups (P gt; 0.05). The repair site in 5-FU group was given 5-FU at a concentration of 25 mg/mL with a soaked sponge, and the synovial sheath of the repaired site was wrapped with the 5-FU-soaked sponge for 1 minute for 4 times after the tendons were repaired; normal sal ine was used in the control group. Results Wound healed by first intention and no infection and tendon rupture occurred in two groups. The patients were followed up for 3-8 months (mean 4.1 months) and 3-8 months (mean 3.9 months) in 5-FU group and in control group respectively. The functional recovery degrees of the fingers were evaluated with total active movement (TAM) evaluation system. In 5-FU group, the results were excellent in 22 fingers, good in 13 fingers, fair in 3 fingers and poor in 1 finger; the excellentand good rate was 89.7%. In control group, the results were excellent in 11 fingers, good in 15 fingers, fair in 9 fingers andpoor in 1 finger; the excellent and good rate was 72.2%. There was statistically significant difference in the functional recovery degrees of fingers between two groups (P lt; 0.05). The 2 fingers which had a poor result in 5-FU group and control group were served with tenolysis was performed in 2 cases having poor results after 6 months of operation and had an excellent result at last. Conclusion 5-FU appl ied topically can reduce tendon adhesions after the ruptured tendon repair.
Abstract An experiment was carried out to investigate the possibility of the establishment of an osteoblasts bank which could supply osteoblasts in repairing bone defect. Osteoblasts were isolated from thetibial periosteum of eight New-Zealand rabbits and cultured in votro. A bone defect, 1.5cm in length was made in both radii of each of the 8 rabbits. The cultivated osteoblasts, gelfoam as a carrier were randomly implanted into the defects of the radii of rabbits. Accordingly, the contralateral radial defects wereimplanted with gelfoam absorbed with the Hanks solution as control. The healing of bone defects was evaluated by roentgenographic examination at 2, 4, 8 and 12 weeks after operation, respectively. It was shown that the implanted cells had osteogenetic capability and could be possible to promote healing of the bone defects. It was suggested that further study needed to be carried out in this field.
OBJECTIVE: To explore the possibility to bridge peripheral nerve defects by xenogeneic acellular nerve basal lamina scaffolds. METHODS: Thirty SD rats were randomly divided into 5 groups; in each group, the left sciatic nerves were bridged respectively by predegenerated or fresh xenogeneic acellular nerve basal lamina scaffolds, autogenous nerve grafting, fresh xenogeneic nerve grafting or without bridging. Two kinds of acellular nerve basal lamina scaffolds, extracted by 3% Triton X-100 and 4% deoxycholate sodium from either fresh rabbit tibial nerves or predegenerated ones for 2 weeks, were transplanted to bridge 15 mm rat sciatic nerve gaps. Six months after the grafting, the recovery of function was evaluated by gait analysis, pinch test, morphological and morphometric analysis. RESULTS: The sciatic nerve function indexes (SFI) were -30.7% +/- 6.8% in rats treated with xenogeneic acellular nerve, -36.2% +/- 9.7% with xenogeneic predegenerated acellular nerve, and -33.9% +/- 11.3% with autograft respectively (P gt; 0.05). The number of regenerative myelinated axons, diameter of myelinated fibers and thickness of myelin sheath in acellular xenograft were satisfactory when compared with that in autograft. Regenerated microfascicles distributed in the center of degenerated and acellular nerve group. The regenerated nerve fibers had normal morphological and structural characters under transmission electron microscope. The number and diameter of myelinated fibers in degenerated accellular nerve group was similar to that of autograft group (P gt; 0.05). Whereas the thickness of myelin sheath in degenerated accellular nerve group was significantly less than that of autograft group (P lt; 0.05). CONCLUSION: The above results indicate that xenogeneic acellular nerve basal lamina scaffolds extracted by chemical procedure can be successfully used to repair nerve defects without any immunosuppressants.