Variation Of Muscle Flap After Wound Healing

The application of muscle flaps are very widespread, which were often used for deepwound repair, depression filling and functional reconstruction. Muscle flap transplantationis one of the most common methods of tissue transplantation in clinical work. Muscle flapis easy to harvest, can also be harvest through a small incision under endoscope, andtherefore has less impact on appearance and function of donor site. Both epidermal skingrafts and split-thickness skin grafts are able to survive well on muscle flap. When usingmuscle flap for depression filling and functional reconstruction, this will occur varyingdegrees loss of muscle mass and bring to the long-term effects of uncertainty. However, ifcovered with muscle flap combined with skin grafts on the defect of soft tissue, muscleatrophy displays its advantages, such as not too bulky, not to be repaired once more,maximize the perfect combination of appearance, function and structure. Therefore, wehave established a model of rabbit latissimus dorsi muscle flap for repairing soft tissue defects of the head, to research the size, weight changes of the muscle and changes inmorphology, histochemistry after the latissimus dorsi muscle flap transplantation, and tocompare the difference between pedicled and free muscle flaps after transplantation.The animal model of rabbit latissimus dorsi muscle flap for repairing soft tissuedefects of the head[Abstract] Objective: To establish a model of rabbit latissimus dorsi muscle flap forrepairing soft tissue defects of the head,to research the morphological changes of atrophyafter the latissimus dorsi muscle flap transplantation. Methods: Imitative free andpedicled rabbit latissimus dorsi muscle flaps with split thickness grafting wererespectively transferred to repair the defects of heads. The common and examinedlatissimus dorsi muscles were selected and analyzed for2,4,8,12,16and24weeksrespectively. The changes of latissimus dorsi thickness, weight and muscle fiber numberwere detected. Results: The histological observation showed that both of the imitativefree and the pedicled latissimus dorsi muscle flaps have the varying degree atrophy，inwhich the imitative free muscle flaps shrink more severely. The examined muscle flapresulted in a35-50%loss in thickness, wet weight and a significant15-25%loss in fibernumber. Accumulation of adipocytes and fibrosis is observed morphological changes ofthis model. Conclusion: A model of latissimus dorsi muscle flap for repairing softtissue defects of the head in rabbit is established,which is a more appropriate animalmodel for the examination of the muscular flap atrophy. The morphological research ofmuscle atrophy provides certain reference for the clinical work.The changes in composition of pedicled and imitative free muscle flap aftertransplantation[Abstract]Objective: To do histochemical study of various fiber types, fibrousconnective tissue, adipose connective tissue and vessels, to observe the changes incomposition after muscle flaps transplantation and its effect on muscle atrophy. Methods:Serial paraffin sections were cut from the mounted specimens, then were carried on Masson staining, immunohistochemical staining, immunofluorescence staining and Tunelstaining. To calculate the changes in muscle composition. Results: The muscle fibercross-sectional area occupied for90%at the beginning and down to40-50%after24weeks, in which type I muscle fiber cross-sectional area ratio decreased from40-45%to5%, type II muscle fiber cross-sectional area ratio decreased from45-60%to25-30%. Thefibrous connection tissue risen from7%before the transfer to40-50%, which type Icollagen increased significantly. Before operation the ratio of adipose tissue was extremelysmall, for24weeks after its cross-sectional area ratio was increased to8-10%. Thevascular bed degeneration was obvious, each muscle fiber was accepted3-5capillarysupplies before operation, but24weeks later each muscle fiber only had one capillarysupply. Conclusion: After transplantation the composition in the muscle changesdramatically, such as apoptosis and degeneration of muscle fiber, proliferation of fibrousconnective tissue, fat cells accumulate, degradation of muscle fibers surrounding thecapillary bed. Meanwhile through the comparison, we discover that denervated muscleflaps in the structural degeneration after transferred are more serious than pedicled musc...