Date of Award

Summer 2000

Document Type

Thesis - Restricted

Degree Name

Master of Science (MS)

Department

Biomedical Engineering

First Advisor

Pintar, Frank A.

Second Advisor

Silver-Thorn, M. Barbara

Third Advisor

Yoganandan, Narayan

Abstract

The introduction of airbags has created new demand for the tolerance levels of pediatric cervical spine strength. In certain out-of-position airbag situations, the airbag adds localized energy into the chin creating injury and death in children and small females. Scale factors to estimate the injury tolerance of children have used several different parameters, but none have used direct experimentation. The difficulty in conducting a direct experimental study is related to the availability of specimens and equipment. By using an animal model, adequate specimens and age groups were available to create a scale factor to assess the tolerance of various pediatric age groups. This study used goat specimens of different age groups to develop scale factors for one-year, three-year, six-year, twelve-year, and adult age groups. Scale factors for linear stiffness, rotational stiffness, load-relaxation, and tensile failure were developed for each group. Twenty-five specimens of varying age created 334 test results. These results were analyzed, and then organized into the scale factor for each loading mode. Several test apparati were developed as part of this thesis. A pure moment application table was designed and built for the rotational testing. Tensile testing interface components for the piston device were created and adapted for use with the tested motion segments and larger column sections. By nature of the specimens tested, a method for securing and mounting vertebrae was developed. The hook and pin configuration was adopted from the literature and developed for use in this study. The inclusion of additional wire mounts and dental acrylic was used to create a more open and secure testing structure. Software programming, test limits, and spreadsheet development was conducted for execution of the experiments and data analysis. Development of the data acquisition codes was performed for all three data acquisition systems. The piston program was developed for each piston test, as well as for triggering the data acquisition. The subsequent data analysis was conducted using various programs and macros created specifically for these tests. The stiffness calculation program was based upon modification of an existing program. The literature on this topic and similar studies created a substantial background for the development and comparison of this research. Through the completion of this study, the first direct experimental study into the strength of the pediatric neck was conducted. The continuation and expansion of this study would enhance the ideas developed here and supplement the answers to questions addressed by this thesis.

Share

COinS

Restricted Access Item

Having trouble?