Identifying Different

Identifying Different Types of Fallers through Gait Analysis Heather Hodnett Dr. Michael Pavol, Department of Nutrition and Exercise Sciences Oregon State University Howard Hughes Medical Institute

Older Adult Falls are an Important Concern • Each year, about 1/3 of adults over age 65 fall • 20-30% of older adults who fall suffer moderate to severe injuries, and 2% of falls result in broken hips • 1 in 5 older adults who break a hip die within 1 yr • In 2000, the annual medical cost of falls was $19 billion, and it is expected to increase to $54 billion by 2020

Gait Matters • Most injurious falls occur while walking • Older adults are more likely to fall if they: • Walk slower • Take smaller steps • Walk with narrower strides • Have weaker hip abductors

Forward Sideways Sideways Backward Fall Direction Matters • Falling sideways increases risk of fracture 6-fold (with direct hip impact, the risk increases 20- to 50-fold) • Propensity to fall sideways has been related to a narrow stride width • Unclear if other aspects of gait affect fall direction

Research Question Do certain aspects of older adults’ gait patterns play a role in the directions they are most likely to fall? If so, what are those aspects?

Hypothesis Sideways fallers will show lesser mediolateral stability during gait and have weaker hip abductors than forward/backward fallers and non-fallers.

Purpose To determine whether and how the gait patterns and hip abductor strengths of older adults differ according to the direction of falls suffered within the past year

The Subjects • Healthy adults over age 65 • Walk unassisted • No conditions that alter balance or gait • Competent and in a sound mental state • Fit into one of three groups: • Non-fallers (N=17) • Forward/backward fallers (N=9) • Side fallers (N=3)

Data Collection • Motion capture system • Body segment movements • 9 cameras • 41 markers • 60 Hz • Force plates • Ground reaction forces • 600 Hz

Walking Trials • ~ 13-foot path • Even, level surface • Preferred walking speed • One step per force plate

Example Image

Data Considerations • Joint angles, rotations, & moments • Trunk sway • Center of mass (COM) distance from the outside of the foot • Hip abductor strength • Compare groups using ANOVA

Minimum COM Medial Distance from Outside of Foot * * *p < .05

Hip Abduction Strength

Discussion • Expected lesser mediolateral stability in side fallers • Forward/backward fallers less stable • May be related to narrow stride width • Side fallers not different than non-fallers • May have adjusted gait for safety • Only 3 side fallers tested so far • Expected lesser abduction strength in side fallers • No difference between groups

Next Steps • Finish current study • Further research to determine differences between sideways, forward/backward, and non-fallers • Fall risk classification based on gait • Possible interventions for decreasing sideways fall risk in older adults

Conclusions • No conclusive results yet • Data suggest: • Forward/backward fallers exhibit lesser mediolateral stability in gait • Hip abduction strength is not related to fall direction or fall incidence

Acknowledgements • Dr. Michael Pavol • Dr. Kevin Ahern • HHMI Program • Cripps Scholarship Fund • LIFE Scholars Program • Center for Healthy Aging Research

Identifying Different