RESUMO
[Objective]To evaluate the results of displaced neck fractures with internal fixation(AO compress cannulated screws) and total hip replacement.[Method]Form 1998.5～2003.10,forty-four patients(mean age 75.2 years) who had an acute displaced femoral neck fracture were treated with internal fixation(21 hips) and total hip replacement(23 hips).The hip function,including the pain,movement and walking,was evaluated by Charnley Score(Charnley improved Merle d' Aubign? score).The health-related quality of patients' life was rated with use of the EQ-5D index.[Result]Forty patients were followed up at least twentyfour months.The ratio of complications in fixation group,defined as nonunion,osteonecrosis and peri-implant fracture,was 36.8%.The ratio of complications in total hip replacement group,defined as dislocation,periprosthetic fracture,or radiographic signs of loosening of the femoral or acetaular component,was 4.7%.There was significance different between two group(P
RESUMO
Objective To prepare porcine acellular dermal matrix(PADM) without cytotoxicity,to evaluate its biological safety,and investigate its end result in vivo.Methods A piece of porcine split-thickness skin of 0.3-0.4mm was obtained,the epidermis was removed by hypertonic saline immersion,and then the skin was immersed in sodium hydroxide solution,and dermal cells were removed by shaking water bath at normal temperature to harvest PADM.After cross-linking and sterilization,bacteria and porcine virus were examined in the PADM.The PADM were embedded beneath the Sprague-Dawley(SD) rat's skin,and then the general and histological changes were observed after transplantation.Result The obtained PADM was soft and elastic,easy to be moulded,and convenient for operation.No cellular component was found in PADM,the collagen was regularly arranged and elastic fibers were abundant.Bacteria and virus examination of all specimens was negative.No immunologic rejection of PADM was found after being embedded beneath the skin of SD rat.The PADM adhered to the wound firmly,and it was difficult to detach 3 weeks after implantation,and the general structures of PADM beneath rat skin were discernible 24 weeks after implantation.The PADM was infiltrated by inflammatory cells in the early stage,fibroblasts and capillary vessels increased in number along with the time,and collagen fibers gradually gained a regular and compact arrangement in PADM.Conclusions The PADM prepared by hypertonic saline/sodium hydroxide method is a simple preparation process,and there is no cytotoxicity.It has a high biological safety and can be used as dermal scaffold with long-term existence in vivo.