Biomechanics of Wheelchair Propulsion

Principle Investigator: Kai-Nan An, Ph.D. and Kenton R. Kaufman, Ph.D.
Project Coordinator: Melissa Morrow — morrow.melissa@mayo.edu
Funding Source: NIH

Wheelchair instrumented with wireless force sensors.

Over 1.5 million Americans rely on manual wheelchairs for mobility and over half report experiencing pain in their shoulders and/or other upper extremity (UE) joints. While there has been a great amount of research invested towards understanding the biomechanics of wheelchair propulsion, no definitive answers have been produced to determine the etiology of this pain. This may be due to the fact that laboratory collection of wheelchair propulsion not fully representing real life conditions.

We proposed to gain a deeper understanding of wheelchair propulsion by starting to obtain field-based data in combination with computer modeling. The first aim of this project was to contrast the forces and moments exerted during outdoor wheelchair propulsion using a pair of wheels instrumented with wireless force sensors with data collected in the typical laboratory setting. The second aim of the study involves the development of a musculoskeletal model to determine the muscle activation patterns of the subjects as they propel on level ground, up a ramp, and along a sideslope. Optimization techniques will be used to determine muscle force distribution and model results will be validated using EMG data. This model will lend insight as to the changes in UE muscle response as users propel over varied terrains. It is our intent to provide a more realistic picture of UE intersegmental joint loads and muscle forces in the natural environment of the user. Subsequently, this will aid in the development of therapeutic means to protect the shoulder from injury.

Publications

• Hurd WJ, Morrow MM, Kaufman KR, An KN. Wheelchair propulsion demands during outdoor community ambulation. J Electromyog Kinesiol., in press.
• Hurd WJ, Morrow MM, Kaufman KR, An KN. Evaluation of upper extremity symmetry among manual wheelchair users over varied terrain surfaces. Arch Phys Med Rehabil., in press.
• Hurd WJ, Morrow MM, Kaufman KR, An KN. Influence of varying level terrain on wheelchair propulsion biomechanics. Amer J Phys Med Rehabil., in press.
• Morrow MM, Hurd WJ, Kaufman KR, An KN. Shoulder demands in manual wheelchair users across a spectrum of activities. Arch Phys Med Rehabil., in submission.