Dr. Stephen Brown
Assistant Professor

Dr. William J Bettger

Email: shmbrown@uoguelph.ca
Office: ANNU 330B
Ext: 53651
Lab: TBA
Ext: TBA

Profile

I began my research career in the summer between my third and fourth undergraduate years, working with Dr Jim Potvin at the University of Windsor. One week into the summer and I was hooked. I continued working with Dr Potvin for my Masters degree, focussing my work on modelling lumbar spine stability, before moving to the University of Waterloo to do my PhD with Dr Stuart McGill, focussing on all aspects of lumbar spine mechanics. During my PhD work I developed a pointed interest in studying, in much greater detail, the mechanics and physiology of the muscles of the spine and abdominal wall, which have extremely unique designs and functions. I therefore decided for my Post-doc to move down to the University of California San Diego to work in the muscle physiology laboratory under the guidance of Drs Richard Lieber and Samuel Ward. Here I developed techniques to study muscle mechanical function at the micro and macro-scopic levels, using novel measurement tools such as laser diffraction to examine sarcomere dynamics. At the University of Guelph I plan to combine all of these tools to study both basic and applied questions regarding the lumbar spine and spine muscles, with the goal of reducing the incidence and prevalence of low-back related pain and injury.

Education

BHK, MHK - University of Windsor
PhD - University of Waterloo
Post-doctoral Fellowship - University of California San Deigo

Research

My research interests are dedicated to understanding the mechanics and physiology of the lumbar spine and spine musculature. This relates to four specific areas of study:

Function of the lumbar spine and spine muscles:
Understanding the anatomy of specific muscles and tissues of the spine, how they interact and are activated (muscles) and loaded (all tissues) to produce controlled movement
Injury to the lumbar spine and spine muscles:
Susceptibility under different loading scenarios
Types and mechanisms of injury
Adaptation of the lumbar spine and spine muscles:
Types of adaptations (to injury, changing internal or external environments)
Are the adaptations beneficial or detrimental?
Rehabilitation of the lumbar spine and spine muscles:
Can detrimental adaptations be reversed or corrected?
Strategies for rehabilitation

Studies in the lab generally follow one of three main paradigms:

Anatomical studies to characterize the mechanical capabilities of muscle and spine tissues:
Dissection and measurement of cadaveric human and animal tissues (eg. measurement of muscle physiological cross-sectional areas and sarcomere lengths to determine force generating and length changing capabilities, respectively)
Modelling of functional capabilities based on these measurements

Mechanical testing of muscle and spine tissues:
Passive and active mechanical properties of different spine muscles
Mechanical interaction between neighbouring muscles and tissues

Testing of human participants to examine muscle activation (EMG), movement patterns and spine loading during a variety of tasks and perturbations:
Modelling muscle force generation, spine loading and stability

Information and insights obtained from the first two paradigms are used to feed into and out of the third paradigm, where the ultimate goal is to further the understanding of our four aforementioned “research themes”: human lumbar spine function, injury, adaptation and rehabilitation.

Selected Publications

Brown, S.H. , Gregory, D.E., Carr, J.A., Ward, S.R., Masuda, K., Lieber, R.L. (in press). 2011 ISSLS Prize winner: Adaptations to the multifidus muscle in response to experimentally induced intervertebral disc degeneration. Spine.

Brown, S.H.M. , Ward, S.R., Cook, M.S., Lieber, R.L. (2011). Architectural analysis of human abdominal wall muscles: implications for mechanical function. Spine, 36, 355-362.

Brown, S.H.M. , Banuelos, K., Ward, S.R., Lieber, R.L. (2010). Architectural and morphological assessment of rat abdominal wall muscles: comparison for use as a human model. Journal of Anatomy, 217, 196-202.

Brown, S.H.M. , McGill, S.M. (2010).A comparison of ultrasound and electromyography measures of force and activation to examine the mechanics of abdominal wall contraction. Clinical Biomechanics, 25, 115-123.

Brown, S.H.M. , Brookham, R.L., Dickerson, C.R. (2010). High-pass filtering EMG in an attempt to better represent the signals detected at the intramuscular level. Muscle & Nerve, 41, 234-239.

Brown, S.H.M. , McGill, S.M. (2009). Transmission of muscularly generated force and stiffness between layers of the rat abdominal wall. Spine, 34, E70-E75.

Brown, S.H.M. , McGill, S.M. (2009). The intrinsic stiffness of the in-vivo lumbar spine in response to a variety of quick releases: implications for reflexive requirements. Journal of Electromyography and Kinesiology, 19, 727-736.

Brown, S.H.M. , McGill, S.M. (2008). Co-activation alters the linear versus non-linear impression of the EMG-torque relationship of trunk muscles. Journal of Biomechanics, 41, 491-497.

Brown, S.H.M. , Gregory, D.E., McGill, S.M. (2008). Vertebral end-plate fractures as a result of high rate pressure loading in the nucleus of the porcine spine. Journal of Biomechanics, 41, 122-127.

Grad Students

M. Gerling (MSc student)