Influences of Massage Head Shape on Mechanical Responses of Human Neck Tissues / 医用生物力学

ABSTRACT

Objective To evaluate the mechanical responses of human neck tissues under the influence of massage head by modeling and simulation, so as to provide guidance for the design of massage apparatus. Methods Gray images of human tissues under application of message head were obtained through CT scanning, and the three-dimensional (3D) model for these tissues was established with reverse engineering method. Changes in strain, stress and message force of muscles and cervical vertebrae under the application of message head with the radius of 15 mm and 10 mm and pressed depth from 0 mm to 10 mm, as well as its damage and influence to bones and tissues were analyzed by finite element method. Results When 15 mm-radius massage head moved in depth of 6 mm and 7 mm, the maximum local stress was 3.0 MPa and 3.4 MPa, which was beyond damage limit of the vein. In contrast, when 10 mm-radius massage head moved in depth of 6 mm and 7 mm, the maximum local stress was 3.2 MPa and 3.7 MPa, which was beyond damage limit of the vein. To derive 1 MPa stress in cervical spine, the 15 mm- and 10-mm radius massage head should move in depth of 8 mm and 6 mm, respectively. Conclusions To avoid the local tissue damages, the pressed depth of massage should not be greater than 5 mm and 7 mm with the 10 mm- and 15 mm-radius message head, respectively. The message head with a larger radius could produce a larger action range and a more moderate massage force.