CHAPTER III

METHODOLOGY

3.1 Research Design:

A research design is the arrangement of conditions for collection and analysis of data in a

manner that aims to combine relevance to the research purpose with economy in

procedure (Kumar, 2008).

The purpose of the present study was:

1. To analyze the gait pattern in post stroke hemiparetic patients

2. To correct the gait pattern in post stroke hemiparetic patients

Accordingly, the study was carried out in two phases:

Phase I: Analysis of gait pattern in post stroke hemiparetic patients

In this phase of study, gait parameters were analyzed in post stroke hemiparetic patients

and then compared with healthy asymptomatic subjects (control group).

Phase II: Correction of gait pattern in post stroke hemiparetic patients

In the 2nd

phase of study, four different types of interventional programs namely, NDT

based gait training; strengthening exercises of lower limb musculature; static cycling; and

conventional physiotherapy were administered for 8 weeks and then compared to

examine their efficacy on the correction of gait pattern in post stroke hemiparetic

patients.

3.2 Nature of study:

Figure 3.1: Flowchart showing the nature of study

Nature of Study

Interventional in

nature Descriptive in

nature

Phase I Phase II

Descriptive research is a most basic type

of enquiry that aims to observe certain

phenomena, typically at a single point in

time.

The aim is to examine a situation by

describing important factors associated

with that situation, such as

demographic, socio-economic, and

health characteristics, events, behaviors,

attitudes, experiences, and knowledge

(Kelley, et al., 2003).

In an intervention study, the subjects are

selected from one population with a

particular characteristic present; then,

immediately after baseline, the total study

group is split up into a group that

receives the intervention and a group that

does not receive that intervention (control

group).

The comparison of the outcomes of the

two groups at the end of the study period

is an evaluation of the intervention

(Everitt & Howell, 2005).

3.3 Research setting:

The study was performed at Ur Physio Physiotherapy Clinic, Jalandhar

3.4 Ethical approval and Consent:

The study was approved by the Board of Post Graduate Studies and Research (Faculty of

Medicine), Punjabi University, Patiala vide letter No. 553/ Research dated 15th

January,

2008 (Annexure I). The subjects were thoroughly explained about the procedure prior to

participation in the study and their informed written consent was taken (Annexure II).

3.5 Duration of study:

For phase I, the duration of the study was from August 2007 to December 2009.

For phase II, the study started in September 2007 and completed in January 2013.

3.6 Sample selection:

Figure 3.2: Flowchart showing the sample selection of study

Participants

Non paretic healthy

asymptomatic controls

Post stroke hemiparetic

patients

Residential colonies

Guru Gobind Singh Nagar

Guru Teg Bahadur Nagar

Model House

Model Town

Doordarshan enclave

Bhargav Nagar

Residential colonies

Guru Gobind Singh Nagar

Guru Teg Bahadur Nagar

Door Darshan Enclave

Model Town

Model House

Basti Sheikh

Basti Guzan

Bhargav Nagar

Urban estate

Tagore Nagar

Saraswati Vihar

Raja Garden

Rose Park

Sant Nagar

Clinics and Hospitals

Ur Physio Physiotherapy Clinic, Jalandhar

Department of Physiotherapy, Lovely

Professional University, Phagwara

Lovely Physiotherapy OPD, Lovely

Autos, Phagwara.

Guru Teg Bahadur Charitable Hospital,

Jalandhar

Figure 3.3: Map displaying the residential colonies of Jalandhar from where data was

collected

3.7 Sampling method:

The method used in present study was the convenient sampling method. This

sampling involves drawing elements from a group that is easily accessible by the

researcher and is one of the most commonly used purposive sampling technique

(Tashakkori and Teddlie, 2003).

3.8 Sample size:

For Phase I, the sample size was of 30 in patient group and 30 in control group.

For Phase II, the sample size was of 20 in each interventional group (The sample

size was calculated as per the formula given in Annexure IV).

Thus, eighty post stroke hemiparetic patients in total.

3.9 Sampling criteria:

The subjects were included acoording to the inclusion criteria described in Figure 3.4.

Figure 3.4: Flowchart showing the inclusion criteria

Non paretic healthy

asymptomatic subjects

Post stroke hemiparetic

patients

1. Age 40-70 years

2. Both males and females

3. Alert and able to follow

commands

4. Able to walk independently

5. Cooperative and compliant

in gait analysis

1. Affected for a period of 4-6 weeks

2. Both males and females

3. Aged 40-70 years

4. Hemiparesis secondary to CVA

5. Having no more than one CVA prior

to testing

6. Able to walk more than 10 meters

with or without gait aid

7. Cooperative and compliant in gait

analysis

8. Alert and able to follow commands

Inclusion criteria

The subjects were excluded according to the following exclusion criteria as described in

Figure 3.5

Figure 3.5: Flowchart showing the exclusion criteria

Non paretic healthy

asymptomatic subjects

Post stroke hemiparetic

patients

Exclusion criteria

1. Comorbid conditions such as disabling

arthritis, amputation, limb length

discrepancy or severe cardiovascular

disease

2. Acute illness

3. Active inflammatory or pathological

changes in the joints of the lower limbs,

or foot deformities (such as pes valgus,

pes cavus, hallux valgus or hallux

rigidus) in the previous 6 months; and

4. History of syncope.

1. Hemiplegia due to trauma, brain tumor

or secondary etiology

2. Completely recovered from the stroke

3. Comorbid conditions such as disabling

arthritis, Parkinson’s disease,

amputation, patients with limb length

discrepancy or severe cardiovascular

disease

4. Acute illness

5. Active inflammatory or pathological

changes in the joints of the lower limbs,

or foot deformities (such as pes valgus,

pes cavus, hallux valgus or hallux

rigidus) in the previous 6 months

6. History of syncope

7. Non-ambulatory

8. Severe visual spatial dysfunction.

3.10 Procedure:

The procedure has been divided into two parts.

1. Phase 1: Analysis of gait pattern in post stroke hemiparetic patients (Figure 3.6)

2. Phase 2: Correction of gait pattern in post stroke hemiparetic patients (Figure 3.7)

Identification of subjects of patient group and control group

Analysis of step length, stride length, cadence, gait velocity and foot

pressure areas

Comparison of gait pattern of patient group and control group

Approval was obtained from Institutional Ethical Committee

Patient group

n = 30

Control group

n = 30

A two days training was undertaken on the “Techniques of Foot pressure

measurement using Harris Mat” in the Department of Prosthetics and Orthotics at

Schieffelin Institute of Health Research & Leprosy Centre, Karigiri, Tamil Nadu

Research proposal was submitted for the approval

Figure 3.6: Flowchart showing the procedure of analysis of gait pattern of post stroke

hemiparetic patients of the present study

All thirty patients of Phase I gave their consent to

participate further in the interventional study

Group A (n= 20) NDT

Based Gait Training with

conventional

physiotherapy (Annexure

6)

Group B (n= 20) Lower

limb Strengthening

exercises with

conventional

physiotherapy (Annexure

7)

Group C (n = 20)

Static Cycling along

with conventional

Physiotherapy

(Annexure 8)

Group D (n = 20)

Conventional

physiotherapy

alone

(Annexure 9)

Intervention was carried out for eight weeks at a frequency of 5 days per week

Another 50 patients were identified to n = 80

Group A Started on

8th Sep 2007 and

ended on 23rd Dec

2012

Group B Started on

15th March 2008 and

ended on 27th Dec

2012

Group C started on

20th Nov 2008 and

ended on 14th Jan

2013

Group D started on

10th Nov 2007 and

ended on 4th Nov

2012

All 80 patients were evaluated thoroughly

Then divided into four groups

Figure 3.7: Flowchart showing the procedure of correction of gait pattern of post stroke

hemiparetic patients of the present study

3.11 Variables of study:

3.11.1 Dependent variables:

Step length

Stride length

Cadence

Gait velocity

Spasticity

Voluntary control

WGS score

Foot pressure areas

3.11.2 Independent variables:

NDT based gait training

Lower limb strengthening exercises

Static cycling

Post correction evaluation of patients was conducted

Conventional physiotherapy

3.12 Tools used:

Harris mat

Ink, roller and chart paper

Marker

Measuring tape

Stop watch

WGS Scale

MAS

Brunnstrom stages of motor recovery classification

3.13 Description of tools:

3.13.1 Harris Mat:

The Harris mat was developed by R.I. Harris and is a rubber mat stretched

across a support frame. The mat has a rough side which consists of ridges of three

different heights lined up in two planes. A light pressure is indicated by only the

large ridges printing, whereas a heavier pressure will progressively print the

smaller and then the smallest ridges in addition to the large ridges (Silvino et al.,

1980). Thus, this mat prints light foot pressure in large, light squares (formed by

tall grid ridges) and heavier pressures in dark, smaller squares (deep ridges). At a

very high pressure, a blotting of ink will obliterate the squares formed by the

ridges. The darker areas are areas of high pressure. It gives a grid analysis of

pressure distribution at a relatively low cost per patient and can be used for static

and dynamic assessment (Sussnan and Batesensen, 2007). This foot printing

technique has been used in clinical studies. The mat is inexpensive, easily used,

and very practical for the clinician. It provides a permanent record of the

distribution of pressure under the foot in an analog mode (Silvino et al., 1980).

For the purpose of taking foot imprints, a portable wooden platform was

constructed in which the Harris mat could be placed. The patient walks on the

platform and steps over the Harris mat which is embedded into the platform so

that there is no height difference between the mat and platform. The patient is thus

able to walk without being conscious.

Figure 3.8: Harris mat

Figure 3.9: Harris mat placed in wooden platform

3.13.2 Ink, roller and chart paper:

The ink was used for application over the Harris mat for the purpose of taking the

foot imprints. The ink was also used for taking the foot prints of the subjects while

walking over the floor in order to calculate step length and stride length. A roller

was required to apply the ink over the Harris mat. The white chart papers were

used for taking the foot imprints using Harrris mat.

3.13.3 Marker:

A marker was used to mark the points over the floor in order to calculate the step

length, stride length and gait velocity.

3.13.4 Measuring tape:

A measuring tape having units of measurement in centimeters was used to

measure the step length, stride length and walking distance for calculation of gait

velocity.

3.13.5 Stop watch:

A stop watch was used in order to calculate the time taken to walk the required

distance for calculation of gait velocity in seconds.

3.13.6 Wisconsin Gait Scale (WGS):

The Wisconsin Gait Scale (WGS), developed in 1996, is a 14-item scale intended

to measure clinically relevant components of gait in persons with stroke

(Annexure V). The WGS uses an ordinal scale to categorize the findings from

Observational Gait Analysis (OGA). WGS can be used to evaluate the gait

problems experienced by a patient with hemiplegia following stroke. This can be

used to monitor the effectiveness of rehabilitation training. WGS proved to have

high intra-rater and inter-rater reliability when administered by physiatrists with

neuro-rehabilitative expertise (Rubertone, et al., 2000; Wellmon, et al., 2003).

The scale consists of four basic measures: -

1. Stance phase of the affected leg.

2. Toe off the affected leg.

3. Swing phase of the affected leg.

4. Heel strike of the affected leg.

The subject is made to walk as observations of the subject are done:

(1) Walking towards the observer

(2) Walking away from the observer

(3) From the side

Each of these measures further consisted of sub-measures as follows: -

I. Stance phase of the affected leg has five sub- measures:

(1) Use of hand held gait aid.

(2) Stance time on impaired side.

(3) Step length of the unaffected side.

(4) Weight shift to the affected side with or without gait aid.

(5) Stance width.

II. Toe off the affected leg has 2 sub-measures: -

(6) Guardedness.

(7) Hip extension of affected side.

III. Swing phase of the affected leg has six sub measures:

(8) External rotation during initial swing.

(9) Circumduction at mid swing.

(10) Hip hiking at mid swing.

(11) Knee flexion from toe off to mid swing.

(12) Toe clearance.

(13) Pelvic rotation.

IV. Heel strike of the affected leg has one sub-measure:

(14) Initial foot contact.

Interpretation:

Minimum score: 13.35

Maximum score: 42

The higher the score the more seriously affected the gait.

3.13.7 Modified Ashworth Scale (MAS):

The Modified Ashworth Scale is a 6-point rating scale that is used to measure

muscle tone. It is a widely used qualitative scale for the assessment of spasticity;

measures resistance to passive stretch (Elovic et al., 2004). The measurements

obtained with the MAS, when a standardized procedure is used in the lower limbs

of people with stroke, have acceptable intrarater reliability on the grade of 0

(Blackburn et al., 2002). This scale has a minimum score of 0 indicating no

increase in tone and maximum score of 4 indicating severe spasticity (Annexure

VI).

3.13.4 Brunnstrom stages of motor recovery:

The voluntary motor control of the lower limb was assessed using the Brunnstrom

stages of motor recovery (Annexure VII).

3.14 Procedure of quantification of gait parameters:

The gait pattern was assessed within a week after the patient had resumed

walking, which was defined as the ability to walk ten to fifteen meters without the

assistance of another individual, with or without gait aid. All subjects, post stroke

hemiparetic patients as well as controls, were instructed to walk along a smooth,

horizontal 10 m long walkway at a comfortable speed.

3.14.1 Quantification of foot pressures using Harris mat:

A wooden platform was constructed in which the Harris mat could be placed and

the subject could step over the Harris mat smoothly without any constraint. The Harris

mat was positioned in the center of the wooden platform and the subject was made to

walk over the platform and instructed to place the foot over the mat while walking. In this

way the foot imprint was taken for both the paretic and non-paretic sides. Later the foot

imprints were analyzed and high pressure and low pressure areas were calculated by

dividing the foot imprint into three parts – Upper part, middle part and lower part.

Figure 3.10 Subject stepping over the platform with Harris Mat

Figure 3.11: Subject stepping over the Harris mat

Figure 3.12: Subject has stepped over the Harris mat

3.14.2 Quantification of step length, stride length, gait velocity and cadence:

The step length (cm) was measured from the geometrical heel center of the

current footprint to the same of the previous footprint on the opposite foot and the stride

length (cm) from the line of progression between the heel points of two consecutive

footprints of the same foot. Only the middle five steps were evaluated to avoid the

variable steps associated with initiation and termination of gait.

For calculation of gait velocity, the subject was instructed to walk in a straight

pathway and the middle 10 meters distance was considered for calculation of gait

velocity. A line was marked indicating the start of the 10 meters and termination of the

10 meters. The time taken to cover this 10 meters distance was recorded. The walking

velocity (cm/s) was obtained after dividing the recorded 10 meters distance by the

ambulation time recorded for this distance.

The cadence was calculated by asking the subject to walk for one minute through

a straight pathway with self-selected speed and then calculating the number of steps taken

during one minute. This distance walked was independent of the 10 m walkway.

3.14.3 Assessment of Wisconsin Gait Scale (WGS) score:

The post stroke hemiparetic patients were examined while walking without the

assistance of orthotic devices, but were allowed to use a gait aid. Each subject was

observed walking towards, walking away from the investigator and from the side.

The parameters were scored in comparison to the normal side. For example, one

of the patients used no gait aid. So he was given 1 point for the first sub measure use of

hand held gait aid. For the second sub measure of stance time on impaired side, he was

given 2 points as his time spent on affected side was unequal as compared to time spent

on unaffected side during single leg stance. Similarly, he was given 3 points for the

seventh sub measure as there was marked hip extension of affected side. For the ninth sub

measure, he was given 2 points, as there was moderate circumduction at mid swing.

However, there was no knee flexion from toe off to mid swing. Therefore, he was given 4

points for the eleventh sub measure. As he was having foot flat on initial foot contact, he

was given 2 points for the fourteenth sub measure. In this way, the scoring was done

using the WGS.

3.14.4 Assessment of spasticity of lower limb musculature:

The spasticity was assessed in Hip adductors, Knee extensors and ankle plantar

flexor muscles. Each subject was put in a resting position for 5 minutes, with socks and

shoes removed. The handling and positioning of the subject’s limbs by the investigator

are described in Annexure VIII. Each test movement was performed over a duration of

about 1 second (by counting “one thousand one”), as described by Bohannon and Smith

(1987). The movement was repeated 3 times because once may not be sufficient for a

rater to attribute a score. After performing the 3 test movements, the investigator graded

the resistance felt, with a single score, according to the MAS.

3.14.5 Assessment of voluntary control of lower limb musculature:

Voluntary control of lower limbs was assessed by using the stages of motor

recovery classification given by Brunnstrom (Annexure VII).

3.15 Gait correction interventions:

3.15.1 NDT based gait training:

The treatment techniques and activities were given as described by Lennon

(2001). The techniques/activities were grouped into 4 categories according to the

treatment goal, preparation, facilitated movements, gait-specific activities, and functional

activities (Annexure IX).

Figure 3.13 The patient stepping with the unaffected lower limb forward

Figure 3.14 The patient stepping with the unaffected lower limb on and off a step

3.15.2 Lower limb strengthening:

The lower limb strengthening protocol required each patient to isotonically exercise the

affected LE using external resistance (Sullivan et al., 2007). The strengthening was done

for six specific muscle groups (hip flexors, hip extensors, knee flexors, knee extensors,

ankle dorsiflexors, and ankle plantar flexors) (Annexure X).

Figure 3.15 The patient being given strengthening exercises for knee flexors

Figure 3.16 The patient being given strengthening exercises for hip flexors

3.15.3 Static cycling:

A static cycler was used for providing gait correction to the group C. The patients were

seated on a static cycle and were asked to complete 10 sets of 15 to 20 revolutions in each

session. They were given at least 2 minutes to rest between sets (Sullivan et al., 2007)

(Annexure XI).

Fig 3.17 The patient performing static cycling

Fig 3.18 The patient performing static cycling

3.15.4 Conventional physiotherapy:

The conventional physiotherapy gait correction program comprised of the exercises in

anatomical planes, passive movements, active movements, passive stretching exercises

etc. (Dickstein et al., 1986). (Annexure XII).

Figure 3.19 The subject being given stretching of hamstrings (Conventional

physiotherapy)

Figure 3.20 The patient being given passive movements (Conventional physiotherapy)

3.16 Dropouts:

The following is the detail about the dropouts in each group:

Group A Group B Group C Group D

1 2 2 3