Development of an end-effector device for loose body removal in hip arthroscopy

Abstract

This article describes a novel hand-operated end-effector device developed for loose body removal in hip arthroscopy. This sterilizable and reusable device incorporates a wire-ball joint mechanism that provides motion with 5 degrees of freedom. The design accounted for the following: (1) the diameter of the femoral head, (2) range of motion of the wrist joint of the operator, (3) ease of assembly of modular parts, and (4) material stiffness and durability. The developed device is composed of three parts: a pistol-shaped hand-held unit, forceps module, and end-effector module, all of which were constructed using polyamide-imide. Experiments were conducted to characterize the range of motion, pushing force, and lateral stiffness of the end-effector. Seven consulting surgeons evaluated the performance of the device in arthroscopic hip model and cadaveric studies in comparison with that of a conventional linear grasper. The experimental results show that the developed device can perform tasks that conventional linear graspers cannot. A specialized end-effector device was developed for hip arthroscopy where a high degree of stiffness is required. The end-effector module is interchangeable based on the required outer diameter, and it is also reusable after sterilization at high temperature.

Stress Dispersion Design in Continuum Compliant Structure toward Multi-DOF Endoluminal Forceps

“…The proposed method can derive parameters in almost real time, even using versatile numerical calculation software. Thus, the proposed method obtained the design parameters with a lower computational cost than the design method of previous research using FEA [24][25][26][27]. The results show the effectiveness of the proposed design method for successful motion generation.…”

“…Polymer materials can be mass-produced at a low cost and discarded after one-time use. PAI (Polyamide-imide) is a biocompatible material with a low Young's modulus and yield strength among similar polymer materials [24]. Therefore, PAI is suitable as a material for the hinge of the forceps.…”

“…In this regard, some studies have used FEA to improve the design of the joint structures [24][25][26][27]. For instance, Park et al [24] and Wu et al [25] evaluated the design optimization by changing the thickness of the hinge using FEA.…”

“…In this regard, some studies have used FEA to improve the design of the joint structures [24][25][26][27]. For instance, Park et al [24] and Wu et al [25] evaluated the design optimization by changing the thickness of the hinge using FEA. Huang et al [26] studied the structural behavior of the snake-like mechanism depending on the dimensions of individual joints and sought to achieve a particular curvature.…”

“…The design optimization approach was validated using a 1-DOF compliant joint with three segments of elastic hinges. However, in these studies [24][25][26][27], a problem arose regarding the high computational cost due to the nonlinear analysis with fine mesh and the exploratory thickness determination of elastic hinges.…”