Finite element analysis of conductive hearing loss caused by fixation and detachment of ligament and tendon in the middle ear

Background and objective: The fixation of ligament and tendon of the middle ear often occurs after chronic otitis media surgery. However, there are relatively few studies on the effect of ligament and tendon on sound transmission in the human middle ear. Here, the finite element model and lumped parameter model are used to study the effect of ligament and tendon fixation and detachment on sound transmission in human ear.Methods: In this paper, the finite element model including the external auditory canal, middle ear and simplified inner ear is used to calculate and compare the middle ear frequency response of the normal and tympanosclerosis under pure tone stimulation. In addition, the lumped parametric model is taken into account to illustrate the effect of ligament and tendon stiffness on the human ear transmission sys-tem.Results: The results indicate that the motion of the tympanic membrane and stapes is reduced by liga-ment and tendon fixation. Although ligament and tendon detachment have a limited effect in the piston-motion direction, the stability of motion in the plane perpendicular to the piston-motion direction is significantly reduced. Most significantly, the ligament and tendon fixation cause a hearing effect of about 18 dB, which is greater in the plane perpendicular to the piston-motion direction after ligament and tendon detachment than in the piston-motion direction.Conclusions: In this study, the calculation accuracy of the lumped parameter and the finite element model is studied, and the effect of ligament and tendon on hearing loss is further explored through the finite element model with high calculation accuracy, which is helpful to understand the role of ligament and tendon in the sound transmission mechanism of the human middle ear. The study of ligament and tendon on conductive hearing loss provides a reference for clinical treatment of tympanosclerosis.(c) 2023 Elsevier B.V. All rights reserved.