Ultrastructural analysis of different-made staplers' staples

AIM: Recently, Chinese-made mechanical staplers with lower price respect to American-made ones have been introduced in clinical practice. In literature, small case series compare the clinical outcomes of different staplers concluding that the new stapler devices perform as well as the American ones. The aim of this study is to compare with an ultrastructural analysis the staples of different staplers in order to verify the existence of differences that might explain significant price disparity and condition clinical outcomes. METHODS: Each stapler was subjected to morphological analysis, energy dispersive X-Ray spectroscopy, metal release assessment followed by inductively coupled plasma mass spectroscopy. P-values were considered statistically significant when <0.05. RESULTS: Autosuture staples have square section whereas the other American one and Chinese made staples have round sections. Roughness index and chips presence before and after ageing tests were comparable for all samples except for Ethicon Endo-Surgery stapler. Energy dispersive X-Ray spectroscopy showed that all staplers are made of pure Titanium but Ethicon Endo-Surgery staples are made with an alloy. Metal release analysis release statistically significant differences between samples in simulated body fluid 20 days solution (P=0.002) and in Aquaregia at 14 days solution. Discussion. Stapling devices have became routinely used in gastrointestinal surgery mainly because of operative time reduction. Recently, new Chinese-made mechanical staplers, with significantly lower prices, have been introduced in clinical practice. In literature, there are some studies that compare clinical outcomes of American-made and Chinese-made staplers on small groups of patients but doesn't exist any work which consider structural differences between traditional and new devices. In our study, for the first time, we propose a comparison between two American-made staplers and three Chinese-made staplers which evaluate morphology, metal composition and chemical staples release. CONCLUSION: Our study suggest that there are some ultrastructural differences between commercially available staplers with no correlation to price disparity. More studies are needed to confirm our results and to verify if our findings could condition clinical outcomes.