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

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1 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 2 nd 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.

2 3.2 Nature of study: Nature of Study Phase I Phase II Descriptive in nature Interventional in nature 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). Figure 3.1: Flowchart showing the nature of study

3 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 15 th 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 For phase II, the study started in September 2007 and completed in January 2013.

4 3.6 Sample selection: 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 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 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 Figure 3.2: Flowchart showing the sample selection of study

5 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).

6 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. Inclusion criteria Non paretic healthy asymptomatic subjects Post stroke hemiparetic patients 1. Age 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 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 Figure 3.4: Flowchart showing the inclusion criteria

7 The subjects were excluded according to the following exclusion criteria as described in Figure 3.5 Exclusion criteria Non paretic healthy asymptomatic subjects Post stroke hemiparetic patients 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. Figure 3.5: Flowchart showing the exclusion criteria

8 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) Research proposal was submitted for the approval Approval was obtained from Institutional Ethical Committee 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 Identification of subjects of patient group and control group Patient group n = 30 Control group n = 30 Analysis of step length, stride length, cadence, gait velocity and foot pressure areas Comparison of gait pattern of patient group and control group

9 Figure 3.6: Flowchart showing the procedure of analysis of gait pattern of post stroke hemiparetic patients of All the thirty present patients study of Phase I gave their consent to participate further in the interventional study Another 50 patients were identified to n = 80 All 80 patients were evaluated thoroughly Then divided into four groups 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 Group A Started on 8 th Sep 2007 and ended on 23 rd Dec 2012 Group B Started on 15 th March 2008 and ended on 27 th Dec 2012 Group C started on 20 th Nov 2008 and ended on 14 th Jan 2013 Group D started on 10 th Nov 2007 and ended on 4 th Nov 2012

10 Post correction evaluation of patients was conducted 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: Dependent variables: Step length Stride length Cadence Gait velocity Spasticity Voluntary control WGS score Foot pressure areas Independent variables: NDT based gait training Lower limb strengthening exercises Static cycling

11 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: 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

12 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.

13 Figure 3.8: Harris mat

14 Figure 3.9: Harris mat placed in wooden platform

15 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 Marker: A marker was used to mark the points over the floor in order to calculate the step length, stride length and gait velocity 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 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 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

16 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.

17 (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: Maximum score: 42

18 The higher the score the more seriously affected the gait 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) Brunnstrom stages of motor recovery: The voluntary motor control of the lower limb was assessed using the Brunnstrom stages of motor recovery (Annexure VII) 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.

19 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.

20 Figure 3.10 Subject stepping over the platform with Harris Mat

21 Figure 3.11: Subject stepping over the Harris mat

22 Figure 3.12: Subject has stepped over the Harris mat 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.

23 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 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

24 was given 2 points for the fourteenth sub measure. In this way, the scoring was done using the WGS 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 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) Gait correction interventions: 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).

25 Figure 3.13 The patient stepping with the unaffected lower limb forward

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

27 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

28 Figure 3.16 The patient being given strengthening exercises for hip flexors

29 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

30 Fig 3.18 The patient performing static cycling

31 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)

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

33 3.16 Dropouts: The following is the detail about the dropouts in each group: Group A Group B Group C Group D