Visual assessment of hemiplegic gait following stroke: pilot study

1100

Visual Assessment of Hemiplegic Gait Following Stroke: Pilot Study Karen A. Hughes,

BSc, Frank Bell, PhD

ABSTRACT. Hughes KA, Bell F. Viiual assessment of hemiplegic gait following stroke: pilot study. Arch Phys Med Rehabil 1994;75:1100-7. a A form that will guide clinicians through a reliable and valid visual assessment of hemiplegic gait was designed. Six hemiplegic patients were filmed walking along an instrumented walkway. These films were shown to three physiotherapists who used the form to rate the patients’ gait. Each physiotherapist rated the six patients at both stages of recovery, repeating this a further two times. This resulted in 10s completed forms. Within-rater reliability is statistically significant for some raters and some individual form sections. Between-rater reliability is significant for some sections. Detailed analysis has shown that parts of the form have caused reduced reliability. These are mainly sections that ask for severity judgments or are duplicated. Some indication of normal gait should be included on the form. To test validity fully the form should be tested on a group of patients who all have significant changes in each objective gait measurement. 0 1994 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabiktion

Assessment of gait by observation is regularly performed by physiotherapists as part of the examination of a hemiplegic patient. This assessment plays a part in determining the treatment techniques to be used. The efficacy of the treatment is determined by an improvement or otherwise in the patient’s gait. However, there are problems with both the standardization and recording of this visual gait assessment causing low reliability and lack of sensitivity.’ Lack of sensitivity and reliability make it difficult to ascertain whether or not there has been a real improvement in the patient’s gait. Although many gait assessment forms have been developed in attempts at standardization, there is still a need for a valid, reliable method of visual hemiplegic gait assessment that provides a detailed description of the patient’s gait.2-5Many of the tested forms give a functional description of gait,637 but these do not provide enough information on which to base a detailed treatment plan. Other stroke assessment forms that are more detailed do not specifically address gait.8 A conclusion reached by some researchersgY” is that visual gait assessment is at best only moderately reliable. In drawing this conclusion, there is an unstated assumption that the lack of reliability is caused by the process of gait assessment itself, rather than the constraints of existing gait assessment forms. Some researchers” have suggested changes to the structure of their form to improve reliability by omitting less reliable items. Others’* suggest that more training in gait assessment may improve reliability. The aim of this study was to design and evaluate a hemiplegic gait assessment form that will provide a more reliable From the Division of Physiotherapy, Glasgow Caledonian University, Glasgow, Scotland. Submitted for publication August 31, 1993. Accepted in revised form May 12, 1994. This research funded by the Scottish Home and Health Department, St. Andrew’s House, Edinburgh, Scotland. Project reference no. KiRED/4/C122. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organizations with which the authors are associated. Reprint requests to Karen A. Hughes, BSc, Division of Physiotherapy, Glasgow Caledonian University. Glasgow, Scotland. 0 1994 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation 0003~9993/94/7510-2434$3.00/O

Arch Phys Mad Rehabil Vol75, October 1994

and standardized method for identifying changes in gait. Many different protocols have been used to test such forms. An important aspect of this study has been to investigate the testing method, both in data collection and analysis of results.

METHOD Design of the Form A list of gait abnormalities that are commonly assessed visually was compiled from previous studies,53’0.‘3*‘4 and by consultation with three specialist physiotherapists who took no further part in the trial. This list was divided into three sections, described as follows. Section A-General Characteristics of Gait. This gives an overall view of the patient’s gait.15,16 Section B-Swing Phase. This analyzes swing phase of hip, knee, and foot and ankle movement. Section C-Stance Phase. Stance was broken down into early-, mid-, and late-stance. This level of detail was used because stance is believed to provide more information on gait quality than swing phase.3,5 A three-point scale was used to rate the degree of abnormality.5 A blank or a tick (1/) in the “Normal” box denoted no abnormality; ‘ ‘ + ’ ’ denoted a barely noticeable abnormality; and “++” denoted a definite abnormality. The form was intended to be used with a video recording of the patient walking. Before full testing, the preliminary form was tested on four academic members of staff in our Physiotherapy Department. Following this, improvements were made to the clarity and presentation of the form. The final version of the form is shown in the figure.

Testing of the Form It was necessary to test the form for within-rater reliability, between-rater reliability, and validity. This involved the recording of videos and temporal-distance gait measurements of six hemiplegic patients at two stages in recovery; use of

VISUAL ASSESSMENT OF HEMIPLEGIC GAIT, Hughes

the form by three independent physiotherapists (raters) to assess the filmed gait of these patients; and analysis of the completed forms by the authors. These three stages will be dealt with in turn.

Data Collection A modified version of the Dalhousie Znshumentation. Walkway was used to record temporal and distance information on the patients’ gaiLI The design and construction of the conductive mats have been modified by staff at Glasgow Caledonian University, but the electronics and software have remained the same. The data are gathered by electronic recording of the time and position of initial foot contact and final contact for right and left foot separately. This information is processed to provide a variety of temporal and distance parameters, including speed and symmetry. There is general agreement that more than one parameter should be used to describe gait, and that speed and some indication of symmetry should be used.4,‘8,‘9The parameters used to measure the patient’s gait quality in this study were speed (normalized to height), step-length symmetry, and single-support symmetry. Two Panasonica VHS camcorders were used to record lateral and anteroposterior views of the patient walking. The signals were also mixed to provide a split-screen film showing both views simultaneously. Patient data. The project was approved by the Ethics Committee of the Southern General Hospital, Glasgow. The relevant consultants gave permission for us to approach patients who had been admitted under their care. Patients were referred to the researchers by physiotherapists working in medical and/or geriatric specialities at the Southern General Hospital. The criteria for referral were as follows: (1) The patients had no other pathology that affected their ability to walk (eg, severe osteoarthritis of lower limb, previous stroke); (2) The patient was capable of walking the length of the walkway (1Om) at least four times (with a rest in between each walk); (3) The patients were likely to make some further recovery, such that they could be filmed at two stages in recovery, and (4) The patient was willing to participate in the trial, after having the procedure explained. Each patient took part in a preliminary trial to allow her or him to become familiar with the walkway and the trial procedure. These results were discarded and the trial proper was performed on the following day. After each data collection session, one walk in each direction was chosen to be shown to the raters. The criteria for selection of a walk were that the video was of reasonable quality and that the objective parameters for each walk were similar. Six suitable patients were recorded at two stages in recovery. For each patient these stages are referred to as Walk 1 and Walk 2. This gave a total of 12 distinct patient-walks. Rater trial. The video recordings were edited into a series of tapes, each with four patient-walks. Three clinical physiotherapists specializing in stroke rehabilitation participated as raters. Each rater had a practice session in which they used the form to assess films of two patients who were not included in the trial. During the trial, each rater assessed each patient-walk

1101

three times on separate occasions. Each rater assessed one tape per session, ie, four patient-walks per session. The raters were allowed to rewind the tape as often as necessary to complete an assessment. Repeat viewings of each patientwalk had been edited into the tapes to minimize the number of rewinds. The raters were asked to complete the assessment of each patient-walk before moving on to the next patientwalk, and to complete a whole number of assessments each time they had a viewing session. They were free to use slowmotion or freeze-frame viewing if they wished. Compliance was not closely monitored, and the raters were encouraged to make any difficulties or lack of compliance known to the researchers. Because of time constraints for the study the patient-walks were not formally randomized across the edited tapes. The minimum period between rater viewings was 2 days, the maximum period was 14 days. Stricter control was not possible because of time constraints. The raters viewed the tapes in their own physiotherapy departments. Each rater observed and assessed 36 patient-walks (6 patients X 3 viewings X 2 stages in recovery), for a total of 108 completed forms.

Methods of Data Analysis Initially, total scores and Section scores were examined to provide an overview of the data. Individual gait characteristics were examined to identify problem areas causing reduced reliability or validity. Calculation of form scores. With reference to the figure, each box on the form represents a gait characteristic. Each box is scored as zero, one (+), or two (++)_ The scores for each section are calculated by adding the box scores. The “Normal” boxes are excluded from this calculation so that a perfectly normal gait would score zero. The maximum score that might be obtained for a person with a grossly abnormal gait is approximately 88. However, it is difficult to calculate an exact maximum score because there are many possible combinations of abnormalities. For Sections A and B, the scores from each box are added to provide an overall score for each section. However, in Section C, the Ankle/Foot subsection is scored differently. The rater was asked to note the foot-to-floor contact region. The researcher then converted this to an anatomical position and scored it for abnormality in the same way as the other sections. The data available for analysis are therefore the scores for individual boxes (0, 1, or 2), the scores for Sections A, B, C, and the score for the whole form (A + B + C). Measures of agreement and stutistical analyses. The form scores have not been investigated for linearity and can only be assumed to form an ordinal scale rather than an interval or ratio scale. Nonparametric statistics were used because of this. Where appropriate, SPSS-PC was used for the analysis. A further approach used was to count the percentage of disagreement within and between raters. Within-rater reliability. An estimate is needed of the ability of one rater to reproduce his or her own results in repeat viewings of the same patient-walk. Kendall’s coefficient of concordance (W) was used to provide this estimate. This is a nonparametric test that measures the overall agreement among more than two sets of rankings.20 The format used Arch Phys Med R&mbit Vol75, October 1994

1102

VISUAL ASSESSMENTOF HEMIPLEGIC GAIT, Hughes Y

\

HEMIPLEGIC GAIT ANALYSIS FORM Therapist

Patient

Date

If a gait characteristic is normal, tick Normal a and go on to the next section. If it is abnormaLthen for the relevant deviation(s), grade as : just noticeably abnormal ++ very noticeably abnormal

SECTION A: General characteristics of gait Head Posture

Normal

I1

Lateral flexion to hemi side

I

Forward flexion

0

Trunk Posture

Normal

Lateral flexion to sound side

0

I

Shortening of hemi side Normal

Movement of centre of gravity

Asymmetrical Rate as + or ++

I

5.

Step characteristics of affected leg

Step characteristics of affected leg Timing:

Length

I

Normal

I

Overall speed too slow

I

Too short

Affected side too short i”Jl

n

Single support time decreased on affected leg

q

Swmg time increased on affected leg

1(401

n

Unaffected side too short 68 1_

n

Normal n

Upper limb positlon Obscured by walking aid (=++)

Shoulder depressed

Shoulder elevated

Poor reciprocal arm swing

Shoulder retracted

Shoulder protracted

Elbow flexed

Arm flaccid

SECTION B: Swing Phase . Hip & Pelvls

n

Normal

(Affected side)

II Excessive internal rotation

Excessive external rotation

Retraction

Excessive abduction

Excessive adduction

Circumduction

Excessive flexion

Excessive extension

Hitching

__ . . . .. ..I nenuplegc gate analysis rorm. Please note that this form most be redesigned and retested before being appropriate

Arch Phys Yed Rehabil Vol75, October 1994

/ / for clinical or research use.

VISUAL

2. Knee

ASSESSMENT

OF HEMIPLEGIC

Normal u Overall lack of movement I

Mainly excessive flexion 0

Mainly excessive extension iI Normal n

3. Ankle I Foot

Poor foot / floor clearance Excessive inversion Excessive plantarflexion

B

Excessive eversion Excessive dorsiflexion

H

SECTION C: Stance Phase 1. Hip 81Pelvis

(Affscted slde)

Normal n

Retraction General instability

q

Excessive external rotation Excessive adduction

Excessive internal rotation Excessive abduction Excessive flexion

Normal

2. Knee

q

I Excessive flexion

Excessive extension n 3. Ankle / Foot Initial contact

1103

GAIT, Hughes

Normal (=C)

tzl

I

Abnormal: Indicate which part(s) of the foot makes contact first

AU

50

Cl

Normal 0 Retraction General instability 5. Knee Excessive extension 6. Ankle I Foot

q Normal

q

Excessive abduction Excessive flexion

Excessive adduction

I

I Excessive flexion

I

Normal (= A+B+C)

I

1

Abnormal: Indicate floor contact area(s)

Retraction General instability

8. Knee Excessive extension 9. Ankle I Foot Final Contact

q

AU

BI

Excessive internal rotation Excessive abduction Excessive flexion

CU

Excessive external rotation Excessive add&on

q

Normal 0 I

Excessive flexion

I

Normal (=A ) 0 Abnormal:

\

Indicate final contact area(s)

Al

Bn

Co

Arch Phys Mod Rehash Vd 75, October 1994

1104

VISUAL ASSESSMENT OF HEMIPLEGIC GAIT, Hughes

Table 1: Total Scores Given by Rater 1 for Walk 1 Assessment Number

Patient Patient Patient Patient Patient Patient

1 2 3 4 5 6

1

2

3

52 20 72 48 32 57

61 11 52 58 45 44

16 04 84 63 36 50

for the analysis is shown in table 1, with sample data. To compare the assessments, W was used ie, to compare columns. This procedure was repeated for Walk 2, and for the other raters. It was then repeated for individual Section scores. It was also necessary to devise a method for examining individual boxes more closely to examine rater consistency in grading individual abnormalities. For the three repeat assessments of each patient-walk the level of inconsistency was estimated by counting the number of times a rater changed from scoring a characteristic as 0 (normal) to 2 (very noticeably abnormal) or vice versa. Each rater carried out three assessments of each patient-walk so there was the possibility of two changes in each set of three assessments (eg, 0 to 2 to 0). The sequence 2 to 0 to 0 has only one change, therefore, there is a dependency on order. For each rater, the number of inconsistencies in a Section was expressed as a percentage of the maximum possible number for that Section. This analysis of changes from 0 to 2, or 2 to 0 was carried out for Sections A, B, and C for each rater individually. The mean for all three raters was also found. Between-rater reliability. Three raters viewed each patient-walk, and an estimate of the level of agreement between raters was needed. Kendall’s coefficient of concordance was used again. As each rater had viewed each patient-walk three times, the tests were carried out on the means of the three form scores for each patient. Total scores and individual section scores were tested. The format was similar to that used for within-rater reliability with the three raters being compared rather than three assessments, Validity. Before examining the changes in the form scores, and correlations with the walkway measurements, it was necessary to examine the changes in the walkway measurements. Hemiplegic gait is more variable than normal gait, but there has been very little previous research into what constitutes a significant change in gait parameters for the hemiplegic patient. Investigations into day-to-day variations in temporal-distance measurements of normal gait show that a change in speed of more than 8% was necessary

for statistical significance, based on a paired f-test.” However, studies on hemiplegic gait show greater variation and recommend minimum changes in speed, between 15% and 25%, to ensure a clinically significant change.22923This study has used a mean of these, and taken a speed change of 20% to be clinically significant. The various phases of gait were also examined, but with respect to the duration of subphases rather than the temporal symmetry.2’ It was reported that the subphases of stance may vary by up to 23%. This was therefore taken as a guideline for the necessary minimum change in single-support symmetry and in step-length symmetry, because steptiming and speed are closely correlated with step length.24P2J For each patient the changes in the walkway measurements between Walk 1 and Walk 2 were compared with the change in the form scores. There are nine scores for each patient-walk (three raters x three viewings) so the mean of these was used for comparison. Spearman’s correlation coefficient (Rho) was used to compare the change in walkway parameters with the change in form scores. RESULTS The concordances and correlations are being used as guidelines to indicate which parts of the form and method should be examined with more detailed analysis.

Within-Rater Reliability This analysis (table 2) shows that Section A is the least consistent section; rater 2 is markedly less consistent than the other two raters; and Walk 1 was less consistently scored than Walk 2. The number of scoring changes from 0 to 2 or vice versa, for all raters for the whole form are shown in table 3. Only those changes that are greater than 5% of the possible number are shown. Table 3 gives a detailed view of individual items in the form, for all three raters. Table 4 details the overall inconsistency level of each Section, calculated in the same way as the results in table 3. The level of inconsistency of each rater, and the mean inconsistency for the three raters is shown.

Between-Rater Reliability Table 5 shows that there is significant agreement between raters on the total scores, but only Section B shows significant agreement for both Walks 1 and 2.

Validity Not all patients had significant changes in all three of their walkway parameters, as shown in table 6.

Table 2: Within-Rater Reliability for Total Scores (T) and Section Scores (Kendall’s Coefficient of Concordance) Walk 2

Walk 1 A Rater 1 Rater 2 Rater 3

.11* .39 .55

B .87* .42 .77*

*p < .05.

Arch Phys Med Rehabil Vol75, October 1994

C .92* .39 .87*

T

A

B

C

T

.90* .40 .73

.97* .67 .80*

.92* .81* .86*

.95* .71 .87*

.95* .91* .93*

1105

VISUAL ASSESSMENT OF HEMIPLEGIC GAIT, Hughes

Table 5: Between Rater ReMebiMy for Total Scores (T) and Section Scores (Kendall’s CodfMent of Concordance)

Table 3: Changes in Rating From 0 (Normal) to 2 (Very No&eddy Abnomal) or Vice Versa as a Pemmtage of the Possible Number of Changes

Scoring Box

Section A A A A A A A A A B B B B B B C C C C C C

Changes from 0 + 2 or2+0 (o/o)

Single support time decreased on affected leg Step length too short Poor reciprocal arm swing Swing time increased on affected leg Trunk shortening on hemi side Elbow flexed Arm flaccid Head in forward flexion Step length too short on unaffected side Hip and pelvis excessive flexion Knee overall lack of movement Ankle/foot excessive plantarllexion Knee mainly excessive flexion Hip and pelvis excessive abduction Knee mainly excessive extension LS hip and pelvis general instability ES hip and pelvis general instability MS hip and pelvis retraction MS hip and pelvis excessive flexion LS hip and pelvis excessive flexion LS knee excessive flexion

18.0 11.0 9.7 8.3 6.9 6.9 6.9 5.5 5.5 9.7 9.7 8.3 6.9 5.5 5.5 11.0 8.3 6.9 5.5 5.5 5.5

Abbreviations: ES, early stance; MS, mid stance; LS, late stance.

Patient 1 improved in speed and step-length symmetry but decreased in single-support symmetry. The correlations between the walkway measurements and the form scores are shown in table 7. Single-support symmetry has the greatest number of significant correlations with the form scores, and step-length symmetry has none. Speed only correlates significantly with the Section A scores.

DISCUSSION Within-Rater Reliability The tendency for Section A to show a lower within-rater reliability (table 2) has been explored by examining the individual scoring boxes more closely (table 3). From this analysis it can be observed that most of the gait characteristics that caused reduced reliability in Section A involved either an assessment of symmetry or a duplication of other categories. Symmetry is examined by asking the rater to compare the affected side with the unaffected side. For example, “trunk shortening on hemi side” and “step length too short on affected side” both look at symmetry. Of the 12 patientwalks, five did not show a marked asymmetry, so although Table 4: Changes From 0 to 2, or 2 to 0 as a Percentage of the Possible Number of Changes

Section A Section B Section C

Rater 1

Rater 2

Rater 3

AU Raters

6.7% 8.3% 7.0%

15.9% 11.8% 13.0%

5.6% 2.5% 0.7%

9.4% 7.4% 7.0%

Walk 1

w

Walk 2

A

B

C

T

A

B

C

T

.72

.75*

.83*

.94*

.90*

.89*

.71

.95*

*p < .05.

each patient-walk had a title stating which side of the patient was affected, it is possible that the raters became confused as to the affected side, particularly because the patient was shown walking toward and away from the camera. This problem could be addressed by showing the patient walking in only one direction. It may not arise if the rater was familiar with the patient, but this would have to await confirmation in a future trial. The inconsistency shown in the upper limb assessment could be caused by duplication of gait characteristics on the form. This introduces the possibility that a consistent opinion of the patient’s level of abnormality may be made inconsistent by the form, ie, by filling in different, but equally appropriate boxes. For example, is a “poor reciprocal arm swing” caused by slow speed, a flaccid arm, or a spastic arm? There is also the possibility that “step length too short” is duplicated by the step length symmetry assessments. A similar analysis carried out on Section B (table 3) showed that there was particular difficulty in deciding on knee position in swing phase. In normal swing phase, the knee moves from extension to flexion and back to extension, so it is difficult to categorize knee movement or knee position during this phase. The analyses of both Section B and Section C showed that there was difficulty in deciding on hip flexion, and that descriptors such as “general instability” and “overall lack of movement” cause unreliability. Future revisions will take these points into account. The tendency for rater 2 to be less self-consistent than the other raters (table 2) is also supported by the analysis of changes from 0 to 2 (table 4). During the trial rater 2 seemed to be less interested than the other raters and tended to run much further behind schedule than the other raters. Rater 2 spent less time on assessment than the other raters although this was not formally monitored. These problems could have been caused by lack of time, and indicate that a redesign of the form should take into account the time available to therapists. Ideally, reliability should not depend on levels of therapist interest, experience, and available time. Table 6: Changes in Walkway Parameters Between Walks 1 and 2

Patient Patient Patient Patient Patient Patient

I 2 3 4 5 6

Speed

sssym

SMYm

63.2% 92.0% 27.1% 102.0% 20.5% 57.0%

-41.8% 8.0% (NS) 5.2% (NS) 35.0% 6.1% (NS) 27.9%

61.6% 4.7% (NS) 50.3% 62.8% 7.0% (NS) 28.8%

Abbreviations: SSSym, single-support symmetry; SLSym, step-length symmetry; NS, not clinically significant.

Arch Phys Med Rehabil Vol75, October 1994

VISUAL

1106

ASSESSMENT

OF HEMIPLEGIC

Table 7: Correlations Between Changes in Walkway Scores and Changes in Form Scores (Spearman’s)

Speed SSSym SLSym

A

B

C

T

.94+ .77 -.31

60 .94t -.09

54 .89* .09

.60 .94+ -.09

*p < .05.

+p < .01.

Some studies have used one of the researchers as a rater.” This may be a useful starting point for an investigation to provide baseline information on reliability. However, an element of bias may be introduced to the study because the researcher is more likely to perform each assessment with due care and attention and may well be working without the pressures of a busy caseload. The researchers may also have been involved in the design of the form. This would give them an insight into what is required by the form and what is meant by any ambiguities. It is unlikely that future users of the form would have this insight, and the reliability of the form for a range of users would still have to be investigated. It is also noticeable (from table 2) that the raters were more self-consistent when assessing Walk 2 than when assessing Walk 1. The reasons for this are not clear. The walks were not shown to the raters in order of filming so it cannot be assumed that the raters were more practiced when they assessed Walk 2. However, the viewing order of the patient-walks was not randomized and this may have had some effect. Lack of control of the time period between rater viewing sessions may also have contributed to the different results of assessments of Walk 1 and Walk 2. It is difficult to draw any conclusions because of the limited amount of data. Video quality may also have been a facto? and could have been improved by better control of lighting and of the color of patients clothing. However, the videos themselves were of similar quality for all patients. In future trials, more careful controlling of the order of presentation, the time-lapse between viewings, and the video quality will be necessary. It may also be necessary to have a more extensive training session for the raters. However, the form will eventually be used in a clinical situation, where the rater is familiar with the patient’s previous performance, and the time-lapse between assessments is not controlled. It is therefore essential to test the form under these more realistic conditions, although preliminary testing should be performed in a more controlled way.

Between-Rater Reliability Only Section B shows significant agreement for Walks 1 and 2. The points discussed previously regarding symmetry and severity could also be the cause of a nonsignificant between-rater reliability. This would also be affected by one rater’s perception of “too short” or “too slow” (for example) being different from another’s. It may be appropriate to include on the form some indication of what is normal, for reference purposes.‘2 Probably the main contributing factor to the lack of reliability of Section C is the level of detail required. The stance Arch Phys Med &habit Vol75, October 1994

GAIT, Hughes

phase is divided into three subphases-early, mid, and late. These subphases may only last a fraction of a second in the more normal patients. Even with repeat viewings the raters have very little time to decide on the characteristics of the subphase. It may be appropriate to include the use of slow motion and freeze frames in future video presentations. It was thought that another factor affecting the reliability may be the scoring differences in the Ankle/Foot subsections. To investigate this, Kendall’s W was recalculated for Section C, omitting the Ankle/Foot subsections. These new concordances were, on the whole, lower. It may be that an outside observer (the researcher) having an input to all of the forms has a leveling effect, masking some of the lack of concordance.

Validity Because some of the changes in walkway measurements between Walk 1 and Walk 2 were nonsignificant (table 6), it is difficult to place much emphasis on the correlations between the changes in walkway measurements and changes in form scores (table 7). To reach any firm conclusions about validity, the form would need to be retested using a group of patients who all had significant changes in each of their objective measurements. CONCLUSION This study has pilot tested a form for visual assessment of hemiplegic gait, using six patients and three raters. The purpose of the study has been to examine the testing method and to investigate the causes of poor reliability of visual gait assessment. To obtain an estimation of the validity of the form in documenting changes in a patients gait, it is necessary to ensure that it is tested using patients who have significant changes in at least three accepted measures of gait quality. Changes that should improve the reliability of the gait assessment form have been identified. Some indication of normal gait seems necessary, particularly for the hip, knee, and ankle as these are assessed in detail. It is also necessary to redesign those sections that require severity judgments, and those that are duplicated elsewhere in the form. Of the methods of analysis used in this study, Kendall’s coefficient of concordance gave a useful indication of which parts of the form should be examined in more detail. However, it would be of more value in a larger scale trial, using more raters. The simple method of counting the number of inconsistencies gave a good indication of the level of reliability of various parts of the form. This was possibly the most valuable type of analysis, although it may be impractical in a large scale study. Acknowledgments: The authors would like Mr. W. Gilchrist and staff at the Rehabilitation eral Hospital, Glasgow, Scotland. We are also patients, consultants, and physiotherapists who

to acknowledge the help of Department, Southern Gengrateful for the help of the were involved in the trial.

References 1. Gems ACH, Mulder T, Rijken RAJ, Neinhuis B. From the analysis of movements to the analysis of skills: bridging the gap between the laboratory and clinic. J Rehabil Sci 1990;3: 102-5. 2. Rose GK. Clinical gait assessment: a personal view. J Med Eng Tech 1983:7:273-9.

VISUAL ASSESSMENT OF HEMIPLEGIC GAIT, Hughes 3. Patla AE, Proctor J, Morson B. Observations on aspects of visual gait assessment: a questionnaire study. Physiother Can 1987;39:31 l-6. 4. Holden MK, Gill KM, Magliozzi MR. Gait assessment for neurologitally impaired patients. Standards for outcome assessment. Phys Ther 1986;66: 1530-9. 5. Krebs DE, Edelstein JE, Fishman S. Reliability of observational kinematic gait analysis. Phys Ther 1985;65:1027-33. 6. Lincoln N, Leadbitter D. Assessment of motor function in stroke patients. Physiotherapy 1979;65:48-5 1. 7. Fug]-Meyer AR, Jaasko L, Leyman I, Olsson S, Steglind S. The post stroke hemiplegic patient. A method for evaluation of physical performance. Stand J Rehabil Med 1975;7: 13-3 1. 8. Keenan MN, Perry J, Jordan C. Factors affecting balance and ambulation following stroke. Clin Ortbop 1984; 182: 165-7 1. 9. Saleh M, Murdoch G. In defence of gait analysis. Observation and measurement in gait assessment. J Bone Joint Surg (Br) 1985;67:23741. 10. Goodkin R, Diller L. Reliability among physiotherapists in diagnosis and treatment of gait deviations in hemiplegia. Percept Mot Skills 1973;37:727. Il. Wolfson L, Whipple R, Amerman P. Tobin JN. Gait assessment in the elderly: a gait abnormality rating scale and its relation to falls. J Gerontol 1990;45:Ml2-9. 12. Eastlack ME, Arvidson J, Snyder-Mackler L, Danoff JV, McGarvey CL. Interrater reliability of videotaped observational gait analysis assessments. Phys Ther 199 1;7 1465-72. 13. Brunnstrom S. Recording gait patterns of adult hemiplegic patients. J Am Phys Ther Assoc 1964;44: 1l-8. 14. LaVigne JM. Sensorimotor assessment form. Phys Ther 1974; 54: l2834.

1107

15. Musa I. Evaluation and re-education of gait following stroke. Physiother Pratt 1986;2:63-73. 16. Baumann JU. Requirements of clinical gait analysis. Hum Movement Sci 1991;10:535-42. 17. Tumbull Gl, Wall JC. The development of a system for the clinical assessment of gait following a stroke. Physiotherapy 1985;71:294-8. 18. Brandstater ME, de Bruin H, Gowland C, Clark BM. Hemiplegic gait: analysis of temporal variables. Arch Phys Med Rehabil 1983;64:583-7. 19. Freidman PJ, Richmond DE, Baskett JJ. A prospective trial of serial gait speed as a measure of rehabilitation in the elderly. Age Ageing 1988; 17:227-35. 20. Seigel S. Nonparametric statistics for the behavioural sciences. lntemational Student edition. Tokyo: McGraw-Hill, 1956:229. 21. Kaiser R, Norton B. Normal gait: test-retest reliability of temporal measures. Program abstracts of the 60th annual conference of the American Physical Therapy Association, Phys Ther 1984;64:711-2. 22. Walker JM, Gronley J, Perry J. Considerations in gait evaluation. In: Proceedings of 10th International Congress of the World Confederation for Physical Therapy. Sydney: World Confederation for Physical Therapy. 1987:658-62. 23. Collen FM, Wade DT, Bradshaw CM. Mobility after stroke: reliability of measures of impairment and disability. lnt Disabil Stud 1990; l2:6-9. 24. Rosenrot P, Wall JC, Charteris J. The relationship between velocity, stride time, support time and swing time during normal walking. J Hum Movement Stud 1980;6:323-35. 25. Kirtley C, Whittle MW, Jefferson RL. Influence of walking- speed on _ gait parameters. J Biomed Eng 1985;7:282-8. 26. Carr EK. Observational methods in rehabilitation research. Clin Rehabil 1991;5:89-94. Supplier a. Panasonic VHS camcorder, Panasonic UK limited, Bracknell, UK.

Arch Phys Wed Rehabil Voi 75, October 1994