RESUMEN
Objectives: To evaluate and compare the in vitro biomechanical results from two stitches: the Mason-Allen stitch, as modified by Habermeyer; and the locked double-tie stitch developed at our service, on tendons of the infraspinatus muscle of sheep. Methods: Twenty tendons from the infraspinatus muscle of sheep were randomly divided into two groups: LDT, on which the locked double-tie stitch was performed; and MA, with the modified Mason-Allen stitch. The evaluation was performed in the mechanics laboratory, using a standard test machine with unidirectional traction, constant velocity of 20 mm per second and a 500 N load cell, without force cycling. Results: We observed that LDT was superior to MA, for the force needed to form spaces of both 5 mm (p = 0.01) and 10 mm (p = 0.002) and also for the maximum traction resistance (p = 0.003). Conclusion: We confirmed our hypothesis that LDT stitches are superior to MA stitches from a biomechanical point of view. This is a further stitching option for surgeons, when fragile and poorly vascularized tendons need to be sutured, and it improves the quality of fixation without increasing the "strangulation" and, consequently, the ischemic area...
Objetivos: Avaliar e comparar os resultados biomecânicos in vitro de dois pontos: o Mason Allen modificado por Habermeyer e o ponto duplo-laço bloqueado (DLB), desenvolvido no nosso serviço em tendões de músculos infraespinais de ovinos. Métodos: Vinte tendões do músculo infraespinal de ovinos foram divididos aleatoriamente em dois grupos: o DLB, no qual foi confeccionado o ponto duplo-laço bloqueado; e o MA, com o ponto Mason-Allen modificado. A avaliação foi feita no laboratório de mecânica, com uma máquina de teste padrão, de tração unidirecional, com velocidade constante de 20 mm por segundo, com uma célula de carga de 500 N, sem ciclagem de força. Resultados: Evidenciamos uma superioridade do DLB sobre o MA, tanto na força necessária para formar 5 mm de espaço (p = 0,01) como 10 mm (p = 0,002) e também na resistência máxima de tração (p = 0,003). Conclusão: Confirmamos nossa hipótese de que o ponto com DLB é superior ao MA do ponto de vista biomecânico. Essa é mais uma opção de ponto para o cirurgião, quando precisa suturar tendões frágeis e pouco vascularizados, e melhora a qualidade da fixação sem aumentar o "estrangulamento" e, consequentemente, a área isquêmica...
Asunto(s)
Humanos , Manguito de los Rotadores , Ovinos , Hombro , Técnicas de SuturaRESUMEN
OBJECTIVE: To ascertain the mean length of radiation emission from fluoroscopic devices during several types of orthopedic surgery and which of these required greater use of radiation. METHODS: The times taken to perform sixteen different types of surgery (total of 80 procedures) were measured. At the end of each procedure, the length of time for which fluoroscopy was used directly from the image intensifier was ascertained. RESULTS: The mean time required for fluoroscopy per operation was 61 seconds. The procedures that demanded greatest mean duration of radiation use were bilateral proximal femoral epiphysiodesis (5.1 minutes) and femoral shaft osteosynthesis using a locked intramedullary nail (3.33 min). CONCLUSION: The mean duration of fluoroscopy use in orthopedic operations was 61 seconds. The procedures using an intramedullary device were the ones that required greatest radiation emission.