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.
Oral carcinoma；Platysma myocutaneous flap；Defect repair
Objective To explore the cl inical outcomes of repairing l imb wound with distal based neurocutaneous flap. Methods From June 2003 to June 2009, 187 cases with wounds in the hand, foot, and distal leg were treated. There were127 males and 60 females aged 20-70 years old (average 37.5 years old). The wound was caused by traffic accident in 130 cases, crush injury in 38 cases, machinery accident in 16 cases, and explosion injury in 3 cases. Among them, the soft tissue defect was in the dorsal and palmar aspects of the hand in 35 cases, the distal leg in 50 cases, the dorsal aspect of foot in 40 cases, the region around ankle in 27 cases, the tendon area in 11 cases, the medial side of foot in 4 cases, the heel and sole of foot in 5 cases, and the forefoot area in 15 cases. The size of skin soft tissue defect was 5.0 cm × 3.0 cm-17.5 cm × 10.0 cm. Four cases suffered from nonunion of heel and 15 cases suffered from tibia defect (3-7 cm). The course of disease was 3 days-8 years. During operation, 35 cases with wound in the hand were treated with three types of lower rotation point of forearm neurocutaneous flaps with rotation points 0-3 cm above the wrist joint, 66 cases were treated with distal based saphenous nerve and saphenous vein neurovascular flaps, muscle flaps and bone flaps with rotation points 2-5 cm above the medial malleolus, and 86 cases were treated with sural and saphenous flaps, muscle flaps and bone flaps with rotation points 1-5 cm above the external malleolus. The flap was 5 cm × 3 cm-17 cm × 15 cm in size, the muscle flap was 5 cm × 3 cm × 1 cm-10 cm × 6 cm × 2 cm in size, the fibula flap was 4.0 cm × 2.5 cm-10.0 cm × 8.0 cm in size. The l igation of the superficial veins was performed below the rotation point of the flap in 163 cases, and the cutaneous nerve ending anastomosis was performed in 22 cases. The donor site was repaired byspl it thickness skin grafting from the inner side of the thigh. Results Various degree of skin flap swell ing occurred, and the swell ing extent in the patients receiving the superficial vein l igation was obvious less than that of patients with no l igation. At 4-7 days after operation, 6 cases had necrosis at the edge of flaps and 6 cases had bl ister, all of them healed after changing dress. The rest skin flaps and skin grafting in the donor site survived uneventfully, and the incision healed by first intention. All the patients were followed up for 2 months to 3 years. The appearance of the flap was satisfactory, the hand function and the foot function of walking and weight-bearing recovered. The two point discrimination of the patients 1 year after cutaneous nerve ending anastomosis was 8-12 mm. The grafted fibula in the patients with bone defect reached union 8-10 months after operation. The appearance and the movement of the donor site were normal. Conclusion The new type distal based neurocutaneous flap has such advantages as simple operative procedure, less invasion, high survival rate, and recovery of the sensory function of the hand and the foot. It is suitable to repair the tissue defect in the hand, the foot, and the distal leg.
Since 1992, the retrograde island skin flap with its pedicle containing the arteria pollicis dorsalis was used to repair 6 cases of the fingertip defects and the results were successful. The skin measured from 1.5cm x 2cm to 4cm x 3.5cm. From the followup, the external appearance of the thumbs looked nice, no limitation of joint motions was noticed and the pain sensation was recovered. The major improvement of this operation was that the donor skin was chosen from the dorsum of the first and second metacarpal bones, thus it was not necessary to divide the tendon of the extensor pollicis brevis, so that the operative procedure was simple and the postoperative functional recovery was rapid.
OBJECTIVE: To study the effect of platelet-rich plasma in the repair of bone defect. METHODS: Segmental bone defects of 1 cm were created in the mid-upper part of bilateral radius of 24 New Zealand white rabbits. One side was randomly chosen as the experimental side, which was filled with artificial bone with platelet-rich plasma (PRP). The other side filled with artificial bone without PRP as the control. After 2, 4, 8 and 12 weeks of implantation, the gross, radiological, histological observations, and computer graphic analysis were performed to investigate the bone healing of the defect in both sides. RESULTS: Two weeks after operation, new bone and fibrous tissue formation in both the experimental and the control sides were observed only in the areas adjacent to the cut ends of the host bone, but the amount of new tissue in the experimental side was much more than that in the control side. In the 4th and 8th weeks, the surface of the artificial bone was covered with a large amount of new bones, the artificial bone was bridged tightly with the host bone by callus in the experimental side, while new bone was limited mainly in the cut ends and was less mature in the control side. In the 12th weeks, bone defects were entirely healed in the experimental side, which were covered completely with cortical bone, while new bone formation was only observed in the ends of artificial bone and there were not continuous bone callus on the surface in the control side. CONCLUSION: Artificial bone with PRP is effective in the repair of segmental bone defects, and PRP could improve the healing of bone defect.
The clinical experiences in the appieation of umbilical-thoracic skin flap in the coverage of the defect of the forearm in 9 cases were reported. The flap was supplied by the branches of inferior epigastric artery.The biggest flap was 8.5×28cm,the smallest one was 7× 16cm.All flaps surviVed.The results were satisfactory. The advantages of the flap were:(1)potients felt comfortable when the upper extremity was immobilized at the side of the they;(2)the size of skin taken from the do...