Karyne N. Rabey, Ph.D.

Assistant Professor


Midwestern University
Chicago College of Osteopathic Medicine
Department of Anatomy
Science Hall 542-E
555 31st St.
Downers Grove, IL 60515

Office: (630) 515-6325
e-mail: krabey@midwestern.edu

EDUCATION

Ph.D. Anthropology University of Toronto 2014
M.Sc. Anthropology Université de Montréal 2007
B.Sc. Anthropology Université de Montréal 2004

RESEARCH SUMMARY

My primary research interests are found in areas that include both the mechanics of locomotion and human musculoskeletal health. I am particularly interested in understanding how certain life history variables influence muscle-bone interactions. Specifically, my research looks at the effects of aging (early and late phases), sex, nutrition, exercise, vibration, and pregnancy on musculoskeletal health. I have been working with many collaborators to document the effects of these variables on bone and muscle strength and have been asking if changes in those properties influence gait and chewing mechanics. I am also looking at these factors in association with osteoporosis, osteoarthritis, and sarcopenia.

Research projects

Project I:

The ability to make behavioral inferences from skeletal remains is critical to understanding the lifestyles and activities of past human populations and extinct animals. Muscle attachment site (enthesis) morphology has long been assumed to reflect muscle strength and activity during life but little experimental evidence exists to directly link activity patterns with muscle development and the morphology of their attachments to the skeleton. I have been using mouse, non-human primate, and human models to test how activity, sex, and age can influence muscle architecture, bone growth rate, bone remodeling, and overall entheseal morphology.

Through dissections and micro-CT scans, I am able to quantify muscle and bone (cortical and trabecular) micro and macro anatomy of many different species, to better understand how each develop, maintain, and age together. Results from my different entheseal projects so far (including my dissertation) show muscle and bone vary with the amount and type of activity performed, however activity has no observable effect on surface entheseal morphology. These emphasize the need for a wide range of information for inferences about bone and muscle properties and function in current and past populations.

Project II:

Although behavioral reconstructions apply well to adult members, very little is known about how age, nutrition, activity, and loading influence bone anatomy. Because the factors that influence bone and muscle growth are complex and change throughout an individual's life history and with diet, our inferences are weakened and some of the central models of biological and cultural evolution remain untested. Humans and other primates are also difficult to study in a controlled fashion; but we can turn to mammalian models to get the needed information. Once we understand the relationship between musculoskeletal anatomy with age and nutrition in a mammalian system, we will be able to apply that knowledge to primate anatomy and test hypotheses about how human and non-human primates may have altered their life history trajectories as longevity increased.

I therefore use mouse models to test the effects of caloric restrictions and age-related changes on mastication, gait patterns, and muscle and bone structural properties. I collect data on temporal gait parameters, ground reactions forces, and loading rates to quantify free locomotion in mice. Upcoming, I would like to take in vivo micro-CT scans to look at the changes in the microstructure of limb and jaw muscles and bones throughout time.

Project III:

It is widely assumed that the demands of gestation have profound effects on bone health and strength. Pregnancy offers an interesting paradox to bone's history: on the one end there is a high demand for calcium provision placed upon the mother to ensure optimal fetal skeletal mineralization, but on the other hand, the maternal bone strength cannot be compromised during an increased load-bearing period. Very few studies have examined the longitudinal effects over a complete reproductive cycle on locomotion and musculoskeletal anatomy. Although some studies try to add weights to mimic the increased loads endured during pregnancy, I am interested in a natural experiment that allows to see changes in locomotion that may occur during gestation.

I compared pregnant mice and rats with aged-matched nulliparous controls to test the effects of increased load-bearing changes on gait patterns and muscle and bone strength. So far, the results in limb loading patterns matched with the fetal skeletal mineralization demands on the mother, caution the reliability to infer behaviors from bone during the reproductive cycle.

Selected Publications

(Full PubMed list)

Characteristics of Vibration that Alter Cardiovascular Parameters in Mice.
Li Y, Rabey KN, Schmitt D, Norton JN, Reynolds RP.J Am Assoc Lab Anim Sci. 2015 Jul;54(4):372-7.

Vibrating Frequency Thresholds in Mice and Rats: Implications for the Effects of Vibrations on Animal Health.
Rabey KN, Li Y, Norton JN, Reynolds RP, Schmitt D.Ann Biomed Eng. 2015 Aug;43(8):1957-64.

Locomotor activity influences muscle architecture and bone growth but not muscle attachment site morphology.
Rabey KN, Green DJ, Taylor AB, Begun DR, Richmond BG, McFarlin SC. J Hum Evol. 2015 Jan;78:91-102. 

Life-long caloric restriction does not alter the severity of age-related osteoarthritis.
McNeill JN, Wu CL, Rabey KN, Schmitt D, Guilak F. Age (Dordr). 2014;36(4):9669.

Collaborators

Daniel Schmitt, Duke University
Shannon McFarlin, The George Washington University
Mark Hamrick, Augusta University
Andrea Taylor, Duke Uniersity
Farshid Guilak, Duke University
Erin Marie Williams-Hatala, Chatham University