Evaluation of the Range of Motion of a Hip Arthroplasty System: A Computer Simulation Study

Abstract

Objective: To date, the literature lacks consensus on the most efficient method to measure the range of motion of an in vitro prosthetic system. In this study, we propose the use of a relatively low-cost online software to measure the range of motion of hip prosthetic implants manufactured in Brazil and compare its results with the current technical standards for hip arthroplasty. Methods: Three different diameters of femoral heads were evaluated (28 mm, 32 mm, and 36 mm). The mean values of the angular displacement of the prosthesis in each motion axis were obtained by computer simulations. Results: The range of motion with each femoral head was 28mm (extension/flexion: 148°, internal/external rotation: 179°, adduction/abduction: 107°), 32 mm (152°/185°/114°), and 36 mm (158°/193°/120°). Conclusion: The computational method showed that the larger the femoral head, the greater the range of motion of the hip joint prosthetic system. Additional clinical studies are necessary to compare the physical results obtained with the values found in this study by computational modeling. Level of evidence V, Experimental study.

A novel algorithm to efficiently calculate the impingement‐free range of motion of irregularly‐shaped total hip arthroplasty components

“…If the elevated‐rim liner is not mounted correctly, the risks of impingement and dislocation are significantly increased 12,16,17 . The current methods used for calculating the IFROM of prostheses include the analytical method, 10,18 the experimental method, 19,20 and the three‐dimensional (3D) simulation method 21,22 . The analytical method features high efficiency but cannot calculate the IFROM for irregularly‐shaped components.…”

“…12,16,17 The current methods used for calculating the IFROM of prostheses include the analytical method, 10,18 the experimental method, 19,20 and the three-dimensional (3D) simulation method. 21,22 The analytical method features high efficiency but cannot calculate the IFROM for irregularly-shaped components. Although the latter two methods can be applied to any shape of hip prosthesis, they consume a lot of time and computing resources.…”