Lower extremity kinematics that correlate with success in lateral load transfers over a low friction surface

Abstract

We previously studied balance during lateral load transfers, but were left without explanation of why some individuals were successful in novel low friction conditions and others were not. Here, we retrospectively examined lower extremity kinematics between successful (SL) and unsuccessful (UL) groups to determine what characteristics may improve low friction performance. Success versus failure over a novel slippery surface was used to dichotomise 35 healthy working-age individuals into the two groups (SL and UL). Participants performed lateral load transfers over three sequential surface conditions: high friction, novel low friction, and practiced low friction. The UL group used a wide stance with rotation mostly at the hips during the high and novel low friction conditions. To successfully complete the practiced low friction task, they narrowed their stance and pivoted both feet and torso towards the direction of the load, similar to the SL group in all conditions. This successful kinematic method potentially results in reduced muscle demand throughout the task.

Practitioner Summary: The reason for this paper is to retrospectively examine the different load transfer strategies that are used in a low friction lateral load transfer. We found stance width to be the major source of success, while sagittal plane motion was altered to potentially maintain balance.

Keywords::

• general ergonomics
• biomechanics
• manual handling
• slips, trips and falls

Acknowledgements

This research was supported by the Liberty Mutual – Harvard School of Public Health Post-doctoral Program as a post-doctoral fellowship awarded to Robert Catena. The authors thank Angela DiDomenico and Jack Dennerlein for their help with research design, and Jake Banks for his help with data collection.

Disclosure statement

The authors do not have financial or personal relationship with other persons or organisations that might inappropriately influence the work presented therein.

Notes

^1. Email: [email protected]