Year of Publication


Degree Name

Master of Science in Biomedical Engineering

Document Type

Master's Thesis




Biomedical Engineering

First Advisor

Dr. Babak Bazrgari


Low back pain (LBP) is a common ailment in the United States, affecting up to 80% of adults at least once in their lifetime. Although 90% of LBP cases are considered nonspecific, recent studies show that abnormal mechanics of the lower back can be a major factor. One method of assessing the lower back mechanical environment is through perturbation experiments. An intensive literature review of perturbation systems was used to select and develop a system for the Human Musculoskeletal Biomechanics Lab (HMBL). Following construction, individuals with high/low exposure to day-long physical activity were assessed to quantify daily changes in their lower back mechanics and determine whether complete recovery occurs during overnight rest. Despite significant decrease in maximum voluntary contractions (MVC), intrinsic stiffness of the high exposure group remained constant following day-long physical activity. The final component of this Master’s project is devoted to the design of a wobble chair system for study of trunk stability. Development of the perturbation system and wobble chair are hoped to facilitate future research aimed at a better understanding of trunk mechanical and neuromuscular behaviors to prevent and treat LBP in the future.