Mechanisms of Fall Resistance to Diverse Slipping Conditions

Summary

Falls are the leading source of injury for all ages, and for older adults are the primary cause of injury related death. Loss of foot to ground traction accounts for 25-40% of falls, typically referred to as a slip. Slips alter the relationship between center of mass and lower limb base of support resulting in altered whole-body angular momentum and inability to support body weight due to loss of stability. But not all slips lead to falls. Stability may be recovered through a combination of response movements, such as swinging the arms or rapid recovery steps. Stability must be recovered quickly otherwise insufficient bodyweight support rapidly leads to a damaging ground collision. A high percentage of falls result in fractures, contusions and sprains to both the trunk and limbs, while slips disproportionately cause lower back injuries. A primary goal of fall prevention training is to improve the ability to resist slips using perturbations that mimic the specific sensory and biomechanical context of natural slip events. However, generating lifelike slip perturbations that mimic the diversity of slipping conditions poses a significant hurdle to improving a more general slip resistance ability. Using movement analysis, the investigators will determine the relationships between diverse slip conditions, reactive responses to slips from those conditions, and slip vulnerability across the gait cycle to generate new data that may guide future interventions.

Conditions

• Slipping and Falls

Interventions

OTHER

Slips on Turns

A slip will be administered to participants at 3 different times in the gait cycle for each of 3 different patch curvatures and 2 different legs for a total of 18 slip episodes. Slips will be delivered while walking along a straight path (infinite radius), or curved paths with radii 2, or 1 meters.

OTHER

Slips on Slopes

Slips will be administered to participants at 3 different times in the gait cycle over sloped ground surface of no slope, ±5.0 and ±10.0 degrees slopes in the direction of walking, and 5.0 and 10.0 degrees perpendicular to the direction of walking. On slopes perpendicular to the direction of walking, slips will be administered to the uphill or downhill foot. A total of 27 slip episodes will be administered. Sloped walking surfaces will be generated with the Computer Assisted Rehabilitation Environment (CAREN) system treadmill.

Sponsors & Collaborators

• National Institute on Aging (NIA)

  collaborator NIH

• University of Nebraska

  lead OTHER

Principal Investigators

• Nathaniel H Hunt, PhD · University of Nebraska

Study Design

Allocation

NON_RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

19 Years

Max Age

35 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2019-12-15

Primary Completion

2021-11-16

Completion

2021-11-16

Countries

• United States

Study Locations