Using the Dynamic Perturbation System to predict Fall Risk in the Elderly

Advisor : Sai Wei YangReporter : Yi Ching Tsai Date : 20070611

Introduction

Demography Fall risk factors The effects of the perturbation training Hypothesis Purpose

Demography

The elderly adults: ≧65 years old The elderly In Taiwan:

1. from 1994 to 2005, 7.38% of population over

65 ys is increased to 9.74%

2. 44.09% of the number of deaths in accidental

falls are the elderly (♂＞♀ )

行政院衛生署 http://www.doh.gov.tw. 2005.

Risk factors add up to falls

Active Independent AgingA community guide for falls prevention and active livingCommunity Health Research Unit, University of Ottawa and Public Health and Long-Term Care Branch, City of Ottawa

Summary of internal and external contributors to falls

FALLS

Internal contributors (age-related deteriorations):Reduced visual acuity, depth perception, and peripheral vision / Vestibular impairment Reduced ability to sense touch and vibration / Reduced static and dynamic balance Reduced walking speed / Poor mobility and gait disorders Reduced strength of the lower extremities / Reduced reaction time Acute illness / Chronic disease / Cognitive impairment / Polypharmacy

external contributors (environment):Inadequate lighting brightness and placement of switches and fixturesLack of handrails on stairs inside and outside of home / Cords and wires on floorLack of grab bars around toilet and bathtub / Lack of nonslip strips on bathtub floorToilet seat that is too low / Polished or waxed floors / Furniture that is too low or is not sturdyThrow rugs that are not secured / Sidewalk cracks and ridges / Ice and snowProsthetic and cane or walker use

-Michael ER et al., 2003.

Fall risk factors

Insufficiency Factors Functions of the factors

1. Muscle strength Maintain dynamic stability

affects speed in early swing

-Louis FD et al., 2004.

-Michael EH et al., 2005.

- Sandra MSFF et al., 2005.-Michael ER et al., 2003.

2. Mobility

to complete the task

Postural changes (voluntarily perturb the body to sway)

- Sandra MSFF et al., 2005.

Fall risk factors

Insufficiency Factors Functions of the factors

3. Balance control Maintain static and dynamic stability

-Louis FD et al., 2004.

4. Range of motion Obstacle crossing

-Louis FD et al., 2004.

The Dynamic Perturbation

1 ： Dynamic Balance System

2 ： RS-ScanFor Pressure changePressure distribution

3 ： EMG-MA300

4 ： Camera5 : Berg Balance Scale

1

2

3

4

- 姚文鈞 , 2003.

Musclestrength

◎Complete the task and maintain the stability Mobility and Postural control

The effects of the perturbation training

• Functional approach based balance training programs may gain largest effects in fall prevention.

-Duncan et al., 1993.

• There was a high correlation between falling index and COP maximum speed and distance.

- 姚文鈞 ,2003.

• Perturbation training provides the stimulus for

reorganizing muscle responses lead to improved

function.• The training changed the knee stabilization strategy to

dynamically stabilize knee in response to unexpected perturbations (increasing knee flexion angle) .

-Terese LC et al., 2005.

Relationship between Perturbation Training Program and Falling

The Perturbation Training Program

Reduce Fall Risk Factors

Motor Control Theory

Postural Control Theory

Motor Learning Theory

ImproveFunctions

Fall

Hypothesis

Using the dynamic perturbation system may improve postural control and reduce the fall risk factors in the elderly

Purpose

To find the best perturbation models and set up a dynamic perturbation training system

To provide a choice in training dynamic

balance

To reduced the number of deaths and

injuries in accidental falls

Methods

Subjects The training program Evaluation

Subjects

age: ≧65 years old with no severe cognitive

impairment, blindness and L/E dysfunction

≧1 fall experience in nearly yearability to walk 10m without assistive device

The training program

Stewart Platform

DOF Technology, Inc. Steward Platform

P5-03 P5-06

P10-03 P10-06

Evaluation

Frequency: Group A: Pre-training, Post-training and per 4 weeks after training Group B: Pretest and after 4 weeks Questionnaires and Instruments :

- The record of falls - The continuous-scale physical functional performance test (CS-PFP) - Evaluation of Range of Motion: Active and Passive

Evaluation

- The Functional reach test

- The dynamic perturbation system with force plate

- The EMG system: MA300

- The foot scan system: RS scan

- The 3D motion analysis system :Vicon MX

- The isokintic dynamometer system: Biodex System

10m

5.1m

9.6m

1.7mForce Plate & Foot Scan

Table

Vicon

Table

Table

Scanner

Dressing room

Mobilization Table

Door

C1

V7V6

V5

V3 V1V2

V4V8

Pedar

Biodex

Storeroom

C2

Stewart Platform

Stewart Platform

when test…

When no test…

Suspensionon ceiling

Table

References1. 行政院衛生署 ,“ 人口統計概況” , 摘自 http://www.doh.gov.tw.2005.2. Luukinen H., Koski K., Hiltunen L., Kivelä S.-L., 1994. Incidence rate of falls in an aged population in Northern Finland. J Clin Epidemiol 47, 843–850.3. Michael ER., Nicole LR., Nobuo T., Mohammod MI., 2003. Methods to assess and improve the physical parameters associated with fall risk in older adults. Preven Med 36, 255–264.4. 4. Michael EH., Heng-Ju L., Li-Shan C., 2005. Increased muscular challenge in older adults during obstructed gait. Gait Posture 22, 356–361.5. 5. Louis FD., Christina EK., 2004. The effects of walking speed on obstacle crossing in healthy young and healthy older adults. J Biomech 37, 889–896.6.6. Sandra MSFF., Silvana AW., Paulo HM., Marcos D., 2005. Age- related changes in human postural control of prolonged standing. Gait Posture 22, 322–330.

Thank you for your attention!

June 27-29, 2007, Taipei, TaiwanJune 27-29, 2007, Taipei, Taiwanhttp://FBS2007.ym.edu.twhttp://FBS2007.ym.edu.tw

Important DatesImportant DatesSubmission of abstract: March 15, 2007Submission of abstract: March 15, 2007Notification of acceptance: April 15, 2007Notification of acceptance: April 15, 2007Early registration due: May 15, 2007Early registration due: May 15, 2007

Organizer:Organizer:National Yang-Ming UniversityNational Yang-Ming UniversityThe Footwear Biomechanics Group, International Society of Biomechanics (ISB)The Footwear Biomechanics Group, International Society of Biomechanics (ISB)

FBS-8FBS-8thth Secretariat SecretariatInstitute of Biomedical Engineering, National Yang-Ming University, Taiwan Institute of Biomedical Engineering, National Yang-Ming University, Taiwan

Tel: +886-2-2820-3062 Fax: +886-2-2821-0847 E-mail: fbs2007@bme.ym.edu.twTel: +886-2-2820-3062 Fax: +886-2-2821-0847 E-mail: fbs2007@bme.ym.edu.tw