Cadaver as an experimental a model for the study of midline incisional hernia

Abstract

. Analysis and interpretation of data and critical revision. ABSTRACT Purpose:To describe a cadaver model and to compare different techniques to correct midline incisional hernia using the tension at the musculoaponeurotic layer as a parameter. Methods: Twenty-four male cadavers were used to characterize the model. The tensile force applied to the anterior layers of the rectus abdominis muscle was measured after the linea alba was resected to create an abdominal wall defect. A dynamometer was used to measure the tensile force necessary to cause a 10-mm displacement of the tissues towards the midline. An index that allows comparison of tensile forces from different points was calculated by dividing the tensile force by the distance between the point of force application at the aponeurosis and the midline. Results: Cadaver is a good model for the study of midline incisional hernia. Conclusion: Cadaver can be used effectively as a model to evaluate tension of the abdominal wall when tissue advancement and musculoaponeurotic flaps are performed in the repair of midline incisional hernia. Key words: Hernia, Ventral. Abdominal Muscles. Tensile Strength. Rectus Abdominis. Cadaver. RESUMO Objetivo:Este estudo descreve o cadáver como modelo experimental para comparar diferentes técnicas para correção da hérnia incisional mediana usando como parâmetro a tensão músculo-aponeurotica. Métodos: Vinte e quatro cadáveres adultos masculinos foram usados para caracterizar este modelo. A força de tensão aplicada na lamina anterior do músculo reto do abdome foi medida após ressecção da linha alba criando um defeito abdominal. Um dinamômetro foi utilizado para medir a força de tensão necessária para ocasionar o deslocamento de 10-mm do tecido até a linha mediana. Um índice para comparar as forças de tensão em diferentes pontos foi calculado dividindo a força de tensão pela distancia entre o ponto de aplicação da força na aponeurose e a linha mediana. Resultados: O cadáver é um bom modelo para estudo da hérnia incisional mediana. Conclusão: O cadáver pode ser utilizado efetivamente como um modelo para avaliação da tensão da parede abdominal quando o avanço de tecidos e retalhos músculo-aponeuroticos são utilizados no reparo de uma hérnia incisional mediana. Descritores: Hérnia Ventral. Músculos Abdominais. Resistência à Tração. Reto do Abdome. Cadaver.

An experimental model for the study of collagen fibers in skeletal muscle

“…It also plays an important part in the transmission of forces resulting from active muscle contraction 3,5 . Collagen is an important component of muscles and fasciae that provides strength to the structures [6][7][8][9] . At present, more than 19 types of collagen have been described 10 , with the types I, II and III being the most studied ones.…”

Relaxation incisions and tensile strength in the abdominal wall of pigs

“…In the technique described by Nahas and Ferreira 3 - 5 , 20 , fresh human corpses were used, which had the alba line removed to promote a defect in the muscle-aponeurotic plane. The tensile strength measurement was also performed with an analog dynamometer.…”

“…The maximum supported capacity is 1kgF (one kilogram-force) or 1000gF (thousand grams-force), the scale being divided every 20gF (twenty grams-force). This dynamometer model has been used successfully in studies to evaluate the tensile strength in the abdominal wall of human cadavers 3 - 5 .…”

“…The abdominal wall suture should have a reduced rate of complications, such as wound dehiscence and incisional hernia (IH) formation. Excessive stress at the edges of the defect after repair is considered a major cause for the development of such complications 5 . Other factors are also associated with the development of IH, such as obesity, old age, malnutrition, technical error during repair, infection, ascites, postoperative hematoma, pregnancy, and other conditions that increase abdominal wall tension or compromise healing at the incision site 3 , 6 .…”

Immunohistochemical analysis of collagen content and types in the rectus abdominis muscle of cadavers of different ages

“…The evaluation of the subtypes of collagen fibers in muscle biopsies has been essential for the diagnosis of different pathological and experimental conditions, such as hypertrophy caused by repetitive strain and sustained work, muscle atrophy due to lack of use or denervation, and longitudinal fiber splitting 11 . There are few reports in the literature on the effects of ageing on human muscles, probably because of the difficulties associated with the performance of serial studies in humans, which may be one of the reasons why most of the studies use animal models [13][14][15][16] . Because it is difficult to obtain muscle biopsy samples from healthy individuals, we opted to use muscle fragments from cadavers, collected at the same site locations (3 cm above and 2 cm below the umbilicus) used in previous studies 15 .…”