BIOMECHANICS PROJECT: Corrective Gait Analysis

BIOMECHANICS PROJECT:Corrective Gait Analysis

ALAN DIONKH 7510

NOVEMBER 29, 2007

INTRODUCTIONSTUDY 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

INTRODUCTIONUSE OF BIOMECHANICS TO CORRECT

PATHOLOGICAL BODY MOVEMENTS

CONSIDERABLE RESEARCH ON CORRECTING PATHOLOGICAL GAITS USING PROTHESES AND ORTHOTICS

LESS RESEARCH ON REVISING GAIT ITSELF

RESEARCHChu, 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.

RESEARCHBurridge, 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.

RESEARCHBurridge, 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.

MEASURESSUBJECT/PARTICIPANT

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)

TEST SUBJECT STAND-IN

MEASURESDARTFISH: 2-D video analysis system

Determine stride length and velocity

Force platform strain gauge: force plateDetermine Ground Reaction Forces (GRFs)

from footfall impactsMeasure z-axis (vertical forces) in Newtons

PROCEDURESVideotape stand-in participant during normal

gait and three corrective/adaptive gaits:CircumductionHip elevation (hip-hitching)Knee flexion (steppage)

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

RESULTSNORMAL AND CORRECTIVE GAITS

NORMAL GAIT: RIGHT FOOT

1 75 149223297371445519593

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NORMAL GAIT: FULL STRIDE

NORMAL GAIT GROUND REACTION FORCESLEFT RIGHT

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CIRCUMDUCTION GAIT

CIRCUMDUCTION GAIT GRFsLEFT RIGHT

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HIP-HITCHING CORRECTIVE GAIT

HIP-HITCHING GAIT GRFsLEFT RIGHT

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KNEE FLEXION CORRECTIVE GAIT

KNEE FLEXION (STEPPAGE) GRFsLEFT RIGHT

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NORMAL GAIT COMPARISONSLeft Step: 0.69 metersRight Step: 0.66 metersStride: 1.35 metersSpeed (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

CIRCUMDUCTION GAITLeft Step: 0.56 metersRight Step: 0.68 metersStride: 1.24 metersSpeed : 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

HIP ELEVATION GAITLeft Step: 0.55 metersRight Step: 0.72 metersStride: 1.28 metersSpeed: 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

KNEE FLEXION GAIT (STEPPAGE)Left Step: 0.55 metersRight Step: 0.68 metersStride: 1.23 metersSpeed: 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

DISCUSSION

PLUSES AND MINUSES FOR ALLCircumduction has :

Big disparity in velocities, step length, GRFsHighest 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 strideLowest Total GRF

CONCLUSIONS (???)No single factor dominates

No one of the adaptive gaits is clearly superiorNone are similar to the normal gait (e.g. left

foot GRFs)

Need more research on how to prioritize factorsE.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?

SPECIAL THANKS:

Kevin Wasco: Videography & Force plate operation

Dr. Mark Geil: Data retrieval