The Clinical And Basic Study Of Artificial Dermal Regeneration Template Pelnac In Complex Orthopaedic Wounds

Part 1 The clinical application of artificial dermal regeneration template Pelnac in complex orthopaedic woundsObjective: To investigate the clinical outcomes of artificial dermal regeneration template(Pelnac)in complex wounds in orthopaedic trauma.Methods:This study was designed as a prospective study.Between March 2013 and May 2017,a total of 16 patients with foot and ankle large size soft tissue defects,13 patients with large size soft tissue defects in hand and forearm in 13 patients,15 patients with the degloved skin injury of the wrist or forearm,and 1 patient with degloved injury of hand failed by traditional flap transplantation but was re-repaired by artificial dermal regeneration template Pelnac and the assistive VSD,were included for data analyses and evaluation.In these complex wounds,bone/tendon exposure was observed upon their admission into hospital or after debridement of the Necrotic tissues.After thorough debridement,the artificial dermal regeneration template Pelnac was used.VSD negative pressure closed drainage was used for 7-10 days,and autologous split-thickness skin graft was performed after 1-2 weeks.In severe cases,VSD negative pressure closed drainage was again performed.Patients who had the degloved injury were treated with one-stage procedure(Pelnac and VSD)to reconstruct and repair tissue defects.Postoperatively,the survival of the skin graft,esthetic appearance,the recovery of nerve function in the grafted area,the recovery of function of the involving adjacent joints,and the overall satisfaction of patients were evaluated.Results: As for the ankle wound,the grafted skin was completely takin in 13 out of 16 patients,and the success rate of “take” was 81.3%.The overall satisfaction rate of the patients with the esthetic appearance of the grafted area was 76.5%,and the VSS scar score was 2.2±2.1,representing the a good level.More than 85% of the patients thought they had the normal or approximately normal sensory function of the grafted area.The average ankle flexion/extension was 48.5±4.8°(range: 35-62°),and 15 patients had satisfactory ankle function recovery.For complicated wounds of the forearm and hand,the complete “take” rate of the grafted skin was 84%,and no complications such as infection,seroma and blisters were found.The patients’ satisfaction rate for esthetic appearance was 75%.The average VSS for scar quality was 2.9.54% of the patients thought that the sensory function of the grafted area was normal or close to normal.The average DASH score was 27.2.As for the wrist or forearm degloving injury,the artificial dermis “take” rate was 87 to 100%,the patients’ subjective satisfaction rate of esthetic appearance was 72%,the VSS score was 2.1,13(87%)patients reported near-normal neurological function recovery,the average DASH score was 21.2,and 14(93%)patients were able to achieve satisfactory level of daily activities.In the case report of a degloving injury repaired by artificial dermis after failure by traditional methods,the patient had satisfactory results at the last follow-up,as for scar quality,esthetic appearance and daily activity level.Conclusion: Artificial dermal regeneration template Pelnac has a good histocompatibility and the good ability to promote wound healing.Combined with negative pressure closed drainage technology(VSD),it can greatly improve the clinical effects and can be used as an alternative for patients with large tissue defects associated with bone/tendon exposure in orthopaedic trauma.Part 2 Experiments of Endless Collagen Promoting Proliferation,Migration and Cavity Formation of Thoracic Aortic Endothelial Cells in VitroObjective: This study was aimed to explore whether the non-terminal collagen can promote the proliferation,migration and angiogenesis of vascular endothelial cells by experiments in vitro on non-terminal collagen,which can be contributed to providing theoretical support for the clinical development of artificial dermal(Pelnac)in complex wounds in orthopaedic trauma.Methods:After anesthesia with formaldehyde solution,the exposed thoracic aorta of rats was dissected and removed under the aseptic condition of ultra-clean platform.Placed in a dish with D-Hanks,then remove the blood and the surrounding connective tissue,then transfered to another dish containing fresh D-Hanks,remove the surrounding fibrous connective tissue again,then gently open the thoracic aorta and completely chop the thoracic aorta to 1mm×1mm size,and evenly planted in 50 ml petri dish,so that the tissue block to ensure a certain gap,and then gently add 4-5ml containing 10% fetal bovine serum DMEM cell culture medium,then cultured in the CO2 incubator(37℃,5%CO2)culture 5 days,After that,change the medium every 2-3 days.After 10 days of culture,the primary cells will occupy about 2/3 of the area of the dish,and when the cells have 80% fusion,they can be passed on next generation.When the old medium is removed away,the cells are washed with autoclave EDTA solution for 2 times,0.25% typsin 2ml is added,and then placed in an inverted microscope,the cells wrinkle and then become rounded,at which point the medium of the equal volume is added to terminate the digestion,Then gently suck and mix with a straw,1500r/min centrifugal 3min,discard the supernatant medium,add the appropriate amount of fresh culture medium,blow and mix the cell suspension.For 2-3 days,changing the medium,then the cells are used for proliferation assay,transwell detection,tube formation experiment and western blotting.Results: Non-terminal collagen can significantly promote the survival and migration ability of rat thoracic aortic endothelial cells.The number of tube formation in rat thoracic aortic endothelial cells was counted and the average was finally taken.The number of non-terminal collagen group(36.67±6.39)was nearly 3 times times of collagen control group(12.33±3.36),suggesting that non-terminal collagen could significantly promote the tube formation of rat thoracic aortic endothelial cells.At last,western blot assay result shows that non-terminal collagen could enhance the expression of VEGF in endothelial cells.Conclusion: Non-terminal collagen can promote the proliferation and migration of endothelial cells.Non-terminal collagen also could promote the tube formation and tissue repair or healing.The potential mechanism for proliferation,migration and tube formation of non-terminal collagen may be achieved by promoting VEGF expression in endothelial cells.