BIOMECHANICS PROJECT: Corrective Gait Analysis - PowerPoint Presentation

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BIOMECHANICS PROJECT:Corrective Gait Analysis

ALAN DION

KH 7510

NOVEMBER 29, 2007

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INTRODUCTION

STUDY THE GAIT OF A MAN UNABLE TO READILY DORSIFLEX HIS RIGHT FOOT DUE TO DAMAGE TO CERVICAL AREA AND NERVES (HEMIPLEGIA)

STUDY ALTERNATE ADAPTIVE/CORRECTIVE GAITS

USING DARTFISH AND FORCE PLATE DATA TO MAKE RECOMMENDATIONS ON PREFERRAL CORRECTIVE GAIT

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INTRODUCTION

USE OF BIOMECHANICS TO CORRECT PATHOLOGICAL BODY MOVEMENTS

CONSIDERABLE RESEARCH ON CORRECTING PATHOLOGICAL GAITS USING PROTHESES AND ORTHOTICS

LESS RESEARCH ON REVISING GAIT ITSELF

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RESEARCH

Chu, T.M & Reddy, N.P. (1995). Stress distribution in the ankle-foot orthosis is used to correct pathological gait.

Journal of Rehabilitation Research and Development

, 32(4), 349-60.

Abnormal motion of the ankle-foot complex is a common problem in stroke victims, who often develop drop foot, involving excessive and uncontrolled plantar flexion. Using an ankle-foot orthosis (AFO) the researchers modeled the GRFs to study the stress distribution in the AFO during the stance phase of gait. Results showed significant stress concentrations in the AFO in heel and neck regions, with maximum compressive stress during heel contact.

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RESEARCH

Burridge, J.H.,

et al.

(2001). Indices to describe different muscle activation patterns, identified during treadmill walking, in people with spastic foot drop.

Medical Engineering & Physics

, 23(6), 427-34.

The study involved individuals unable to dorsiflex due to lesions of CNS, such as hemiplegia following stroke. The researchers tested subjects with hemiplegia against age-matched unimpaired individuals for treadmill walking. Results showed more dissimilarity in calf activation between the impaired and unimpaired subjects in push-off and early stance than in TA during swing, but the hemiplegic subjects lacked the second peak of activity in initial foot contact.

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RESEARCH

Burridge, J.H. & McLellan, D.H. (2000). Relation between abnormal patterns of muscle activation and response to common peroneal nerve stimulation in hemiplegia.

Journal of Neurology, Neurosurgery and Psychiatry

, 69(3), 353-62.

Researchers used functional electrical stimulation of the peroneal nerve in 18 stroke patients with drop foot and 12 unimpaired subjects. Results showed that patients with the worst control of ankle movement had the best improvement, while those with mechanical resistance to passive movement who had more normal activation responded less well. This supported the hypothesis that stimulation of the peroneal nerve to activate TA also inhibits the antagonist calf muscles.

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MEASURES

SUBJECT/PARTICIPANT

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THE PARTICIPANT(S)

STAND-IN

“SUBJECT”

Gender: Male

Age: 56 years

Height: 67 in. (170.2 cm)

Weight: 154 lbs. (70 kg)

Inseam: 29 in. (73.7 cm)

Gender: Male

Age: 81 years

Height: 69.5 in. (176.5 cm)

Weight: 152.5 lbs. (69.3 kg)

Inseam: 30 in. (73.7 cm)

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TEST SUBJECT STAND-IN

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MEASURES

DARTFISH: 2-D video analysis system

Determine stride length and velocity

Force platform strain gauge: force plate

Determine Ground Reaction Forces (GRFs) from footfall impacts

Measure z-axis (vertical forces) in

Newtons

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PROCEDURES

Videotape stand-in participant during normal gait and three corrective/adaptive gaits:

Circumduction

Hip elevation (hip-hitching)

Knee flexion (

steppage

)

Have subject perform all four gaits across force plate in GSU Biomechanics Lab

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RESULTS

NORMAL AND CORRECTIVE GAITS

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NORMAL GAIT: RIGHT FOOT

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NORMAL GAIT: FULL STRIDE

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NORMAL GAIT GROUND REACTION FORCES

LEFT

RIGHT

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CIRCUMDUCTION GAIT

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CIRCUMDUCTION GAIT GRFs

LEFT

RIGHT

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HIP-HITCHING CORRECTIVE GAIT

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HIP-HITCHING GAIT GRFs

LEFT

RIGHT

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KNEE FLEXION CORRECTIVE GAIT

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KNEE FLEXION (STEPPAGE) GRFs

LEFT

RIGHT

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NORMAL GAIT COMPARISONS

Left Step: 0.69 meters

Right Step: 0.66 meters

Stride: 1.35 meters

Speed (ave.): 1.24 meters/second

Average GRF - Left: 369.9 N; Right: 338.1 N

Maximum GRF – Left: 799.8 N; Right: 755.9 N

Sum of GRFs - Left: 221,558.0 N Right: 219,946.2N

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CIRCUMDUCTION GAIT

Left Step: 0.56 meters

Right Step: 0.68 meters

Stride: 1.24 meters

Speed : Left = 1.14 m/s; Right = 0.87 m/s

Average GRF - Left: 312.7 N; Right: 291.4 N

Maximum GRF – Left: 723.0 N; Right: 819.1 N

Sum of GRFs - Left: 314,192.2 N Right: 236,796.4N

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HIP ELEVATION GAIT

Left Step: 0.55 meters

Right Step: 0.72 meters

Stride: 1.28 meters

Speed: Left = 0.92 m/s; Right = 0.90 m/s

Average GRF - Left: 302.4 N; Right: 300.3 N

Maximum GRF – Left: 657.1 N; Right: 770.4 N

Sum of GRFs - Left: 276,430.6 N Right: 257,727.2N

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KNEE FLEXION GAIT (STEPPAGE)

Left Step: 0.55 meters

Right Step: 0.68 meters

Stride: 1.23 meters

Speed: Left = 1.01 m/s; Right = 0.88 m/s

Average GRF - Left: 311.4 N; Right: 258.2 N

Maximum GRF – Left: 739.3 N; Right: 808.7 N

Sum of GRFs - Left: 286,873.8 N Right: 233,959.7N

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DISCUSSION

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PLUSES AND MINUSES FOR ALL

Circumduction has :

Big disparity in velocities, step length, GRFs

Highest overall velocity, so closest to Normal

Hip-hitching has :

Less disparity in velocities and GRFs (ave. & max)

Biggest disparity in step lengths

Knee flexion has :

Big disparities in everything; shortest stride

Lowest Total GRF

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CONCLUSIONS (???)

No single factor dominates

No one of the adaptive gaits is clearly superior

None are similar to the normal gait (

e.g.

left foot GRFs)

Need more research on how to prioritize factors

E.g.

Is lower total GRF more important than max GRF as far as impacts to heel and neck of ankle? Toe off?

Is uniformity of stride more important than velocity?

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SPECIAL THANKS:

Kevin Wasco: Videography & Force plate operation

Dr. Mark Geil: Data retrieval