A combination of experimental and finite element analyses of needle–tissue interaction to compute the stresses and deformations during injection at different angles

Abstract

One of the main clinical applications of the needles is its practical usage in the femoral vein catheterization. Annually more than two million peoples in the United States are exposed to femoral vein catheterization. How to use the input needles into the femoral vein has a key role in the sense of pain in post-injection and possible injuries, such as tissue damage and bleeding. It has been shown that there might be a correlation between the stresses and deformations due to femoral injection to the tissue and the sense of pain and, consequently, injuries caused by needles. In this study, the stresses and deformations induced by the needle to the femoral tissue were experimentally and numerically investigated in response to an input needle at four different angles, i.e., 30°, 45°, 60°, and 90°, via finite element method. In addition, a set of experimental injections at different angles were carried out to compare the numerical results with that of the experimental ones, namely pain score. The results revealed that by increasing the angle of injection up to 60°, the strain at the interaction site of the needle-tissue is increased accordingly while a significant falling is observed at the angle of 90°. In contrast, the stress due to injection was decreased at the region of needle-tissue interaction with showing the lowest one at the angle of 90°. Experimental results were also well confirmed the numerical observations since the lowest pain score was seen at the angle of 90°. The results suggest that the most effective angle of injection would be 90° due to a lower amount of stresses and deformations compared to the other angles of injection. These findings may have implications not only for understating the stresses and deformations induced during injection around the needle-tissue interaction, but also to give an outlook to the doctors to implement the most suitable angle of injection in order to reduce the pain as well as post injury of the patients.

Neural microprobe modelling and microfabrication for improved implantation and mechanical failure mitigation

“…For example, the ‘kill zone' described by Hamzavi et al is defined as regions with more than 5% strain [29]. Stress at the implantation angle θ is compared numerically to the 90° case as per equations ((6.1)–(6.8)) adapted from Halabian et al [30]. right left right left right left right left right left right left3pt0em 2em 0em 2em 0em 2em 0em 2em 0em 2em 0emtrueσz90∘ =FA, right left right left right left right left right left right left3pt0em 2em 0em 2em 0em 2em 0em 2em 0em 2em 0emtrueσzθ =PA±MycIy=PA±Vzc112ab3=PA±Vzh2112Ab2, right left right left right left right left right left right left3pt0em 2em 0em 2em 0em 2em 0em 2em 0em 2em 0emtrueσzθ =FcosθA±Fsin⁡θzh2112Ab2=(cos⁡θ±6sin⁡θhzb2)…”

“…For example, the ‘kill zone' described by Hamzavi et al is defined as regions with more than 5% strain [ 29 ]. Stress at the implantation angle θ is compared numerically to the 90° case as per equations ((6.1)–(6.8)) adapted from Halabian et al [ 30 ]. …”

Finite Element Analysis of Needle Insertion Angle in Insulin Therapy

“…The needle was assumed to be in 'tie' and its tip to be fully inserted into skin model according to Halabian et al [10] as this would minimise errors during simulation of finite element analysis. In Mimics software, the needle and skin models were loaded as STL file.…”

“…Some studies have been conducted to evaluate needle insertion for femoral vein catheterization in different angles, however, the evaluation of needle used in insulin therapy is still limited in the literature [10]. Furthermore, the research also stresses on different angles of needle insertion cause a different level of injury and pain to the skin.…”

“…The main objective of this study is to evaluate the favourable angle of needle insertion in insulin therapy by evaluating the maximum stress and strain of skin and needle model via finite element method [10]. Finite element method is a numerical method that can simulate the behaviour of human as well as other models [13][14][15][16].…”