Accepted Manuscript Exergaming with additional postural demands improves balance and gait in patients with multiple sclerosis as much as conventional balance training and leads to high adherence to home-based balance training Andreas Kramer , Dr. Christian Dettmers , Prof. Markus Gruber , Prof. PII:
S0003-9993(14)00340-2
DOI:
10.1016/j.apmr.2014.04.020
Reference:
YAPMR 55825
To appear in:
ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION
Received Date: 18 February 2014 Revised Date:
10 April 2014
Accepted Date: 21 April 2014
Please cite this article as: Kramer A, Dettmers C, Gruber M, Exergaming with additional postural demands improves balance and gait in patients with multiple sclerosis as much as conventional balance training and leads to high adherence to home-based balance training, ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION (2014), doi: 10.1016/j.apmr.2014.04.020. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Running head: Exergame balance training with MS patients Title: Exergaming with additional postural demands improves balance and gait in patients with multiple sclerosis as much as conventional balance training and leads to high adherence to home-based balance training
RI PT
Authors: Dr. Andreas Kramer1, Prof. Christian Dettmers2, Prof. Markus Gruber1 1 Sensorimotor Performance Lab, Department of Sports Sciences, University of Konstanz, Germany 2 Kliniken Schmieder Konstanz, Germany
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Acknowledgements: The authors want to thank Simon Sailer and Anne Ruchay-Plößl for their help with the patient recruitment, Alexandra Narr, Christine Bächle, Sandra Pfadler and Gregor Eichhorn for their help with the data acquisition and training supervision, Nathan Stern for reviewing and offering advice on the draft of the manuscript and Ulrich Kübler and Peter Kern for their contributions to the study design. Ethical standards and Conflict of interest: The experiments conducted in this study comply with the current German laws and were approved by the local ethics committee. This research was partly supported by EADS Astrium (framework cooperation agreement between the University of Konstanz and EADS Astrium Friedrichshafen). The authors declare that they have no conflict of interests.
TE D
Author for correspondence: Dr. Andreas Kramer FG Sportwissenschaft Universität Konstanz 78457 Konstanz Phone: +49 7531 88 4923 Email: [email protected]
AC C
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Clinical trial registration number: DRKS00004520
ACCEPTED MANUSCRIPT
1
Title: Exergaming with additional postural demands improves balance and gait in patients
2
with multiple sclerosis as much as conventional balance training and leads to high adherence
3
to home-based balance training
5
RI PT
4 Abstract
6
Objective: To assess the effectiveness of and the adherence to an exergame balance training
8
program with additional postural demands in patients with multiple sclerosis (MS)
9
Design: Matched controlled trial, assessment of balance before and after different balance
10
training programs and adherence to home-based balance exercise in the six months after the
11
training
12
Setting: Kliniken Schmieder, a neurorehabilitation facility and center for multiple sclerosis in
13
Konstanz, Germany
14
Participants: 70 MS patients with balance problems, matched into one of the training groups
15
according to age as well as balance and gait performance in four tests. Nine patients dropped
16
out due to scheduling problems. Mean age of the 61 remaining participants was 47±9 years,
17
EDSS 3±1
18
Interventions: Three weeks of either i) conventional balance training (control), ii) exergame
19
training (playing exergames on an unstable platform, EG), iii) single-task (ST) exercises on
20
the unstable platform
21
Main outcome measures: Test scores in balance tests and gait analyses under ST and DT.
22
Furthermore, in the six months following the rehabilitation training, frequency and type of
23
balance training was assessed through questionnaires.
24
Results: All three groups showed significantly improved balance and gait scores. Only the EG
25
showed significantly higher improvements in the DT condition of the gait test than in the ST
AC C
EP
TE D
M AN U
SC
7
1
ACCEPTED MANUSCRIPT
condition. Adherence to home-based balance training differed significantly between groups
27
(highest adherence in EG).
28
Conclusions: Playing exergames on an unstable surface seems to be an effective way to
29
improve balance and gait in MS patients, especially in dual task situations. The integration of
30
exergames seems to have a positive effect on adherence and is thus potentially beneficial for
31
the long-term effectiveness of rehabilitation programs.
RI PT
26
SC
32
Keywords: balance training, dual task, fall prevention, neurological rehabilitation, Nintendo
34
Wii
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33
35 36
Abbreviations: conventional training group (CG), dual task (DT), exergame group (EG),
37
multiple sclerosis (MS), Posturomed group (PG), single task (ST)
38
TE D
39
Persons with Multiple Sclerosis (MS) have an increased fall and fracture risk compared to the
41
fall or fracture risk of age-matched control groups1. Most studies examining the falls of
42
persons with MS report fall rates of about 50% over the course of a year 2, 3. These high fall
43
rates have been mainly attributed to poor postural control 4, as balance and gait impairments
44
can be used to distinguish fallers and non-fallers 5.
AC C
45
EP
40
46
One situation that has been identified to have a particularly high fall risk is multitasking while
47
walking
48
reduce this high fall risk in multitask situations, it would be reasonable to incorporate balance
49
exercises with simultaneous motor or cognitive tasks into balance training programs.
50
Surprisingly, there are only few studies that investigated the effects of dual-task (DT) balance
51
training 10-12 or compared it to conventional single-task (ST) balance training 13, 14. The results
6-9
, i.e., performing one or more cognitive or motor tasks in addition to walking. To
2
ACCEPTED MANUSCRIPT
of these studies suggest that DT balance training improves balance in DT test situations more
53
than ST training 13, 15, while ST balance training shows higher effects in ST situations, but no
54
or only small improvements in DT test situations 16. However, to our knowledge no study has
55
examined the effects of DT balance training in persons with MS yet.
RI PT
52
56
Another important aspect that has to be taken into consideration when designing a training
58
intervention is adherence. Adherence seems to be closely linked to the enjoyment of the
59
training: studies monitoring adherence to training programs found that in addition to factors
60
such as personal goals, practical barriers or social support for the program, the reaction to the
61
program, i.e., whether the participants enjoyed it or not, was a factor discriminating between
62
continuing participants and dropouts
63
enjoyment might be the use of exergames, i.e., video games that incorporate some kind of
64
physical exercise. The efficacy of exergames (particularly those which incorporate the
65
Nintendo Balance Board) as an alternative form of balance training has been examined in
66
several studies with positive results. Recent studies reported balance improvements in ST
67
tests after several weeks of Wii Fit exergames in healthy older adults
68
Parkinson’s Disease
69
note that these studies trained and tested only under ST conditions, and some had no control
70
group. The studies that assessed enjoyment or adherence in addition to balance usually
71
reported high enjoyment and good adherence to the training program for Wii Fit training 21, 26.
72
However, when compared to other forms of training, Wii Fit training appears to improve
73
balance to a lesser extent
74
differences between a Wii Fit training and a control group with no training 30. Therefore, Wii
75
Fit training alone seems to be a motivating and enjoyable form of ST balance training, but
76
should be combined with other forms of balance training in order to achieve results that are
77
comparable to the improvements observed after conventional forms of balance training.
17, 18
. One way to achieve high levels of training
TE D
24, 25
M AN U
SC
57
26
and MS
, patients with
27-29
. However, it is worthy of
AC C
EP
, Acquired Brain Injury
19-23
20, 22
. In persons with MS, one study even found no significant
3
ACCEPTED MANUSCRIPT
78 The aim of our study was to compare a new kind of balance training that combines exergames
80
with additional postural demands to two single-task balance training programs with respect to
81
efficacy and adherence in persons with MS. We hypothesized that the new exergame training
82
would show higher effects than the other two forms of training, especially in the DT tests and
83
the adherence to home-based balance training after the training period.
SC
84 85 Methods
M AN U
86
RI PT
79
87
Patients: Seventy patients with MS volunteered to participate in this study. Participants were
89
recruited from the MS inpatients of the Kliniken Schmieder, a neurorehabilitation facility and
90
center for multiple sclerosis in Konstanz, Germany. Nine patients dropped out of the study
91
due to scheduling problems caused by the clinic or the experimenters. Of the remaining 61
92
participants, 44 were female and 17 male, their mean age (±standard deviation) was 47±9
93
years, height 171±8 cm, body mass 72±14 kg and expanded disability status scale (EDSS)
94
3±1. Before taking part in the study, all participants gave written informed consent to the
95
experimental procedure, which was in accordance with the latest revision of the Declaration
96
of Helsinki and approved by the ethics committee of the University of Konstanz. The study
97
was registered as a clinical trial in the German Register for Clinical Trials (DRKS00004520).
98
Inclusion criteria were an EDSS≤6, no relapse in the past three months and the
99
recommendation from the physiotherapists that the patient needed balance training (assessed
100
with questionnaires and Romberg and one-leg stance tests). To avoid group differences due to
101
randomization, the participants were then matched to one of three training groups: exergame
102
training group (EG, 21 participants), Posturomed training group (PG, 20 participants), or
103
conventional training group (CG, 20 participants). Group-matching was performed according
AC C
EP
TE D
88
4
ACCEPTED MANUSCRIPT
104
to age as well as balance and gait performance in four tests (one-leg stance on the preferred
105
leg, Romberg stance with eyes closed, one-leg stance on the Posturomed and DT gait
106
velocity).
RI PT
107 Study design and tests: In order to test the effects of the three-week training regimen, all
109
subjects were tested before and after the training period. Prior to the tests, all participants
110
were familiarized with the various tests and practiced performing them correctly. The tests
111
consisted of six static balance tests on a force platea, four balance tests on an unstable surface
112
(Posturomedb) and two gait analyses (Optogaitc). For the balance tests, the participants were
113
instructed to stand as still as possible for 10 seconds. The six force plate tests included: twice
114
Romberg stance (once with eyes open, once with eyes closed) and four times one-leg stance
115
(preferred leg, non-preferred leg, preferred leg with eyes closed, preferred leg with the
116
additional task of typing a given, random number sequence into a mobile phone). On the
117
Posturomed, the participants underwent four tests: they had to stand on both legs without an
118
additional task, stand on their preferred leg without an additional task, stand on both legs with
119
the additional destabilizing task of performing a Wiid golf pitch with a defined amplitude (that
120
each participant had to practice about 20-30 times beforehand) and stand one their preferred
121
leg with the additional golf pitch task. The gait analysis consisted of normal walking in a ten-
122
meter Optogait corridor and walking while having to answer questions (e.g., “How many
123
surfaces does a cube have?”).
M AN U
TE D
EP
AC C
124
SC
108
125
Each test was performed twice. The order of the tests was balanced between participants to
126
control for confounding effects such as fatigue.
127 128
Training: All the participants trained over a period of three weeks, with a total of nine
129
supervised training sessions lasting 30 minutes each. A training session for the EG consisted 5
ACCEPTED MANUSCRIPT
of playing Wii Sports/Sports Resort/Fit games that require arm movements (tennis, table
131
tennis, boxing, archery and sword fight) or displacements of the whole body to control the
132
game avatar (ski slalom, balance bubble, penguin picnic, soccer heading, tilt city and perfect
133
ten). The games that were chosen most often were table tennis, tennis and tilt city. While
134
playing these games, the patients stood on an unstable surface (the Posturomed) that swings
135
when the patient moves his limbs or is not in balance. So in order to keep their balance while
136
playing, they constantly had to make postural adjustments, thus increasing the postural
137
demands of the exergame task. If a normal stance on the Posturomed was too easy for the
138
patient (i.e., little platform movement), he was instructed to use a more challenging type of
139
stance, gradually increasing from “Romberg stance” (feet together) to tandem stance (one foot
140
in front of the other) to one-leg stance. The purpose of the PG was to assess whether training
141
improvements were due to the combination of the exergame task and the added postural
142
demands of the Posturomed in the EG or simply due to the Posturomed training. Therefore,
143
the PG also trained on the Posturomed, but performed about five ST balance exercises of a
144
pool of 15 exercises with increasing difficulty, ranging from standing on the Posturomed on
145
both legs as still as possible to standing on your toes or heels to standing on one leg while
146
moving one arm quickly as if hitting a tennis ball. The CG served as a reference to assess the
147
efficacy of the new combined exergame training in comparison to a standard balance training
148
in rehabilitation. The patients assigned to the CG participated in the conventional balance
149
training of the Schmieder rehabilitation clinic, which consisted of various exercises on the
150
floor: Romberg stance, tandem stance, standing on the toe or the heel, walking forwards and
151
backwards on a line, tandem walk and one-leg stance on an aerobic mat.
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EP
TE D
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SC
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130
152 153
In addition to the balance training, the participants of all three groups underwent the
154
rehabilitation program of the clinic, consisting of physiotherapy, occupational therapy, speech
155
therapy and neuropsychology according to the individual deficits and rehabilitation aims. 6
ACCEPTED MANUSCRIPT
156 Adherence: During the six month after their treatment in the rehabilitation clinic, each
158
participant was asked to do weekly prospective reports about the amount and type of balance
159
training they performed, with possible answers including: Wii on unstable surface; unstable
160
surface; conventional training like in the clinic; other (describe); no home-based training only
161
general physiotherapy; none. Additionally, they had to report how many falls they had had
162
that week. Note that no training prescription was given to any of the participants. If they did
163
not return these training and fall reports, they were contacted at the end of the six month and
164
asked about their training type and duration as well as the number of falls. Three out of the 61
165
participants could not be contacted and were therefore excluded from the adherence analyses.
166
Sixteen out of the 58 included participants regularly returned the weekly reports (EG: 6, PG:
167
6, CON: 4), the other 42 were contacted at the end of the six months.
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SC
RI PT
157
168
Data processing: The parameters that were exported for analysis were the accumulated sway
170
path during the 10s test intervals (force plate and Posturomed), the gait velocity and the step
171
length for each step in the 10m walkway (gait analysis). The results were averaged over the
172
two trials performed for each test. Failed trials were not repeated and excluded from data
173
analysis. From the fall and training reports, the following data were analyzed: cumulative
174
number of falls, predominant type of balance training and average weekly training time. The
175
person in charge of the data analysis was blinded with respect to participants’ group affiliation.
EP
AC C
176
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169
177
Statistics: Group data are presented as means ± standard deviations (SD). The required
178
sample size was estimated to be 66 participants (power of 0.8, alpha error probability of 0.05,
179
effect size of 0.2). The effect of the training on the recorded balance and gait parameters was
180
evaluated using two-factor analyses of variance, group [3 levels: EG, PG, CG] x time [2
181
levels: pre and post]. False discovery rate was controlled according to the Benjamini– 7
ACCEPTED MANUSCRIPT
Hochberg–Yekutieli method. To reveal differences between ST and DT improvements, the
183
post-training values were normalized to the pre-training values and analyzed using an
184
ANOVA, group [3 levels: EG, PG, CG] x task [2 levels: DT, ST]. Significant interaction
185
effects were followed up with paired t-tests. The training and fall reports were analyzed with
186
the Chi-square test, except for the training time, which was analyzed with the Kruskal-Wallis
187
test and Mann-Whitney U post-hoc tests. The analyses were performed with SPSS 19.0 (SPSS,
188
Inc., Chicago, IL).
SC
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182
189
191
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190 Results
192
Most of the statistical tests showed significant improvements in the recorded balance and gait
194
parameters, as indicated by the significant main effect of time, see tables 1, 2 and 3. None of
195
the balance tests showed a significant group x time interaction effect, i.e., all three groups
196
showed similar improvements after the training. However, when comparing the step-to-step
197
variability improvements during ST to those during DT (see figure 1), a significant group x
198
task interaction was evident (F(2,52)=9.3, p
S0003-9993(14)00340-2
DOI:
10.1016/j.apmr.2014.04.020
Reference:
YAPMR 55825
To appear in:
ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION
Received Date: 18 February 2014 Revised Date:
10 April 2014
Accepted Date: 21 April 2014
Please cite this article as: Kramer A, Dettmers C, Gruber M, Exergaming with additional postural demands improves balance and gait in patients with multiple sclerosis as much as conventional balance training and leads to high adherence to home-based balance training, ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION (2014), doi: 10.1016/j.apmr.2014.04.020. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Running head: Exergame balance training with MS patients Title: Exergaming with additional postural demands improves balance and gait in patients with multiple sclerosis as much as conventional balance training and leads to high adherence to home-based balance training
RI PT
Authors: Dr. Andreas Kramer1, Prof. Christian Dettmers2, Prof. Markus Gruber1 1 Sensorimotor Performance Lab, Department of Sports Sciences, University of Konstanz, Germany 2 Kliniken Schmieder Konstanz, Germany
M AN U
SC
Acknowledgements: The authors want to thank Simon Sailer and Anne Ruchay-Plößl for their help with the patient recruitment, Alexandra Narr, Christine Bächle, Sandra Pfadler and Gregor Eichhorn for their help with the data acquisition and training supervision, Nathan Stern for reviewing and offering advice on the draft of the manuscript and Ulrich Kübler and Peter Kern for their contributions to the study design. Ethical standards and Conflict of interest: The experiments conducted in this study comply with the current German laws and were approved by the local ethics committee. This research was partly supported by EADS Astrium (framework cooperation agreement between the University of Konstanz and EADS Astrium Friedrichshafen). The authors declare that they have no conflict of interests.
TE D
Author for correspondence: Dr. Andreas Kramer FG Sportwissenschaft Universität Konstanz 78457 Konstanz Phone: +49 7531 88 4923 Email: [email protected]
AC C
EP
Clinical trial registration number: DRKS00004520
ACCEPTED MANUSCRIPT
1
Title: Exergaming with additional postural demands improves balance and gait in patients
2
with multiple sclerosis as much as conventional balance training and leads to high adherence
3
to home-based balance training
5
RI PT
4 Abstract
6
Objective: To assess the effectiveness of and the adherence to an exergame balance training
8
program with additional postural demands in patients with multiple sclerosis (MS)
9
Design: Matched controlled trial, assessment of balance before and after different balance
10
training programs and adherence to home-based balance exercise in the six months after the
11
training
12
Setting: Kliniken Schmieder, a neurorehabilitation facility and center for multiple sclerosis in
13
Konstanz, Germany
14
Participants: 70 MS patients with balance problems, matched into one of the training groups
15
according to age as well as balance and gait performance in four tests. Nine patients dropped
16
out due to scheduling problems. Mean age of the 61 remaining participants was 47±9 years,
17
EDSS 3±1
18
Interventions: Three weeks of either i) conventional balance training (control), ii) exergame
19
training (playing exergames on an unstable platform, EG), iii) single-task (ST) exercises on
20
the unstable platform
21
Main outcome measures: Test scores in balance tests and gait analyses under ST and DT.
22
Furthermore, in the six months following the rehabilitation training, frequency and type of
23
balance training was assessed through questionnaires.
24
Results: All three groups showed significantly improved balance and gait scores. Only the EG
25
showed significantly higher improvements in the DT condition of the gait test than in the ST
AC C
EP
TE D
M AN U
SC
7
1
ACCEPTED MANUSCRIPT
condition. Adherence to home-based balance training differed significantly between groups
27
(highest adherence in EG).
28
Conclusions: Playing exergames on an unstable surface seems to be an effective way to
29
improve balance and gait in MS patients, especially in dual task situations. The integration of
30
exergames seems to have a positive effect on adherence and is thus potentially beneficial for
31
the long-term effectiveness of rehabilitation programs.
RI PT
26
SC
32
Keywords: balance training, dual task, fall prevention, neurological rehabilitation, Nintendo
34
Wii
M AN U
33
35 36
Abbreviations: conventional training group (CG), dual task (DT), exergame group (EG),
37
multiple sclerosis (MS), Posturomed group (PG), single task (ST)
38
TE D
39
Persons with Multiple Sclerosis (MS) have an increased fall and fracture risk compared to the
41
fall or fracture risk of age-matched control groups1. Most studies examining the falls of
42
persons with MS report fall rates of about 50% over the course of a year 2, 3. These high fall
43
rates have been mainly attributed to poor postural control 4, as balance and gait impairments
44
can be used to distinguish fallers and non-fallers 5.
AC C
45
EP
40
46
One situation that has been identified to have a particularly high fall risk is multitasking while
47
walking
48
reduce this high fall risk in multitask situations, it would be reasonable to incorporate balance
49
exercises with simultaneous motor or cognitive tasks into balance training programs.
50
Surprisingly, there are only few studies that investigated the effects of dual-task (DT) balance
51
training 10-12 or compared it to conventional single-task (ST) balance training 13, 14. The results
6-9
, i.e., performing one or more cognitive or motor tasks in addition to walking. To
2
ACCEPTED MANUSCRIPT
of these studies suggest that DT balance training improves balance in DT test situations more
53
than ST training 13, 15, while ST balance training shows higher effects in ST situations, but no
54
or only small improvements in DT test situations 16. However, to our knowledge no study has
55
examined the effects of DT balance training in persons with MS yet.
RI PT
52
56
Another important aspect that has to be taken into consideration when designing a training
58
intervention is adherence. Adherence seems to be closely linked to the enjoyment of the
59
training: studies monitoring adherence to training programs found that in addition to factors
60
such as personal goals, practical barriers or social support for the program, the reaction to the
61
program, i.e., whether the participants enjoyed it or not, was a factor discriminating between
62
continuing participants and dropouts
63
enjoyment might be the use of exergames, i.e., video games that incorporate some kind of
64
physical exercise. The efficacy of exergames (particularly those which incorporate the
65
Nintendo Balance Board) as an alternative form of balance training has been examined in
66
several studies with positive results. Recent studies reported balance improvements in ST
67
tests after several weeks of Wii Fit exergames in healthy older adults
68
Parkinson’s Disease
69
note that these studies trained and tested only under ST conditions, and some had no control
70
group. The studies that assessed enjoyment or adherence in addition to balance usually
71
reported high enjoyment and good adherence to the training program for Wii Fit training 21, 26.
72
However, when compared to other forms of training, Wii Fit training appears to improve
73
balance to a lesser extent
74
differences between a Wii Fit training and a control group with no training 30. Therefore, Wii
75
Fit training alone seems to be a motivating and enjoyable form of ST balance training, but
76
should be combined with other forms of balance training in order to achieve results that are
77
comparable to the improvements observed after conventional forms of balance training.
17, 18
. One way to achieve high levels of training
TE D
24, 25
M AN U
SC
57
26
and MS
, patients with
27-29
. However, it is worthy of
AC C
EP
, Acquired Brain Injury
19-23
20, 22
. In persons with MS, one study even found no significant
3
ACCEPTED MANUSCRIPT
78 The aim of our study was to compare a new kind of balance training that combines exergames
80
with additional postural demands to two single-task balance training programs with respect to
81
efficacy and adherence in persons with MS. We hypothesized that the new exergame training
82
would show higher effects than the other two forms of training, especially in the DT tests and
83
the adherence to home-based balance training after the training period.
SC
84 85 Methods
M AN U
86
RI PT
79
87
Patients: Seventy patients with MS volunteered to participate in this study. Participants were
89
recruited from the MS inpatients of the Kliniken Schmieder, a neurorehabilitation facility and
90
center for multiple sclerosis in Konstanz, Germany. Nine patients dropped out of the study
91
due to scheduling problems caused by the clinic or the experimenters. Of the remaining 61
92
participants, 44 were female and 17 male, their mean age (±standard deviation) was 47±9
93
years, height 171±8 cm, body mass 72±14 kg and expanded disability status scale (EDSS)
94
3±1. Before taking part in the study, all participants gave written informed consent to the
95
experimental procedure, which was in accordance with the latest revision of the Declaration
96
of Helsinki and approved by the ethics committee of the University of Konstanz. The study
97
was registered as a clinical trial in the German Register for Clinical Trials (DRKS00004520).
98
Inclusion criteria were an EDSS≤6, no relapse in the past three months and the
99
recommendation from the physiotherapists that the patient needed balance training (assessed
100
with questionnaires and Romberg and one-leg stance tests). To avoid group differences due to
101
randomization, the participants were then matched to one of three training groups: exergame
102
training group (EG, 21 participants), Posturomed training group (PG, 20 participants), or
103
conventional training group (CG, 20 participants). Group-matching was performed according
AC C
EP
TE D
88
4
ACCEPTED MANUSCRIPT
104
to age as well as balance and gait performance in four tests (one-leg stance on the preferred
105
leg, Romberg stance with eyes closed, one-leg stance on the Posturomed and DT gait
106
velocity).
RI PT
107 Study design and tests: In order to test the effects of the three-week training regimen, all
109
subjects were tested before and after the training period. Prior to the tests, all participants
110
were familiarized with the various tests and practiced performing them correctly. The tests
111
consisted of six static balance tests on a force platea, four balance tests on an unstable surface
112
(Posturomedb) and two gait analyses (Optogaitc). For the balance tests, the participants were
113
instructed to stand as still as possible for 10 seconds. The six force plate tests included: twice
114
Romberg stance (once with eyes open, once with eyes closed) and four times one-leg stance
115
(preferred leg, non-preferred leg, preferred leg with eyes closed, preferred leg with the
116
additional task of typing a given, random number sequence into a mobile phone). On the
117
Posturomed, the participants underwent four tests: they had to stand on both legs without an
118
additional task, stand on their preferred leg without an additional task, stand on both legs with
119
the additional destabilizing task of performing a Wiid golf pitch with a defined amplitude (that
120
each participant had to practice about 20-30 times beforehand) and stand one their preferred
121
leg with the additional golf pitch task. The gait analysis consisted of normal walking in a ten-
122
meter Optogait corridor and walking while having to answer questions (e.g., “How many
123
surfaces does a cube have?”).
M AN U
TE D
EP
AC C
124
SC
108
125
Each test was performed twice. The order of the tests was balanced between participants to
126
control for confounding effects such as fatigue.
127 128
Training: All the participants trained over a period of three weeks, with a total of nine
129
supervised training sessions lasting 30 minutes each. A training session for the EG consisted 5
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of playing Wii Sports/Sports Resort/Fit games that require arm movements (tennis, table
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tennis, boxing, archery and sword fight) or displacements of the whole body to control the
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game avatar (ski slalom, balance bubble, penguin picnic, soccer heading, tilt city and perfect
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ten). The games that were chosen most often were table tennis, tennis and tilt city. While
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playing these games, the patients stood on an unstable surface (the Posturomed) that swings
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when the patient moves his limbs or is not in balance. So in order to keep their balance while
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playing, they constantly had to make postural adjustments, thus increasing the postural
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demands of the exergame task. If a normal stance on the Posturomed was too easy for the
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patient (i.e., little platform movement), he was instructed to use a more challenging type of
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stance, gradually increasing from “Romberg stance” (feet together) to tandem stance (one foot
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in front of the other) to one-leg stance. The purpose of the PG was to assess whether training
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improvements were due to the combination of the exergame task and the added postural
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demands of the Posturomed in the EG or simply due to the Posturomed training. Therefore,
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the PG also trained on the Posturomed, but performed about five ST balance exercises of a
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pool of 15 exercises with increasing difficulty, ranging from standing on the Posturomed on
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both legs as still as possible to standing on your toes or heels to standing on one leg while
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moving one arm quickly as if hitting a tennis ball. The CG served as a reference to assess the
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efficacy of the new combined exergame training in comparison to a standard balance training
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in rehabilitation. The patients assigned to the CG participated in the conventional balance
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training of the Schmieder rehabilitation clinic, which consisted of various exercises on the
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floor: Romberg stance, tandem stance, standing on the toe or the heel, walking forwards and
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backwards on a line, tandem walk and one-leg stance on an aerobic mat.
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In addition to the balance training, the participants of all three groups underwent the
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rehabilitation program of the clinic, consisting of physiotherapy, occupational therapy, speech
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therapy and neuropsychology according to the individual deficits and rehabilitation aims. 6
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156 Adherence: During the six month after their treatment in the rehabilitation clinic, each
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participant was asked to do weekly prospective reports about the amount and type of balance
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training they performed, with possible answers including: Wii on unstable surface; unstable
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surface; conventional training like in the clinic; other (describe); no home-based training only
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general physiotherapy; none. Additionally, they had to report how many falls they had had
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that week. Note that no training prescription was given to any of the participants. If they did
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not return these training and fall reports, they were contacted at the end of the six month and
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asked about their training type and duration as well as the number of falls. Three out of the 61
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participants could not be contacted and were therefore excluded from the adherence analyses.
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Sixteen out of the 58 included participants regularly returned the weekly reports (EG: 6, PG:
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6, CON: 4), the other 42 were contacted at the end of the six months.
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Data processing: The parameters that were exported for analysis were the accumulated sway
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path during the 10s test intervals (force plate and Posturomed), the gait velocity and the step
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length for each step in the 10m walkway (gait analysis). The results were averaged over the
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two trials performed for each test. Failed trials were not repeated and excluded from data
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analysis. From the fall and training reports, the following data were analyzed: cumulative
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number of falls, predominant type of balance training and average weekly training time. The
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person in charge of the data analysis was blinded with respect to participants’ group affiliation.
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Statistics: Group data are presented as means ± standard deviations (SD). The required
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sample size was estimated to be 66 participants (power of 0.8, alpha error probability of 0.05,
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effect size of 0.2). The effect of the training on the recorded balance and gait parameters was
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evaluated using two-factor analyses of variance, group [3 levels: EG, PG, CG] x time [2
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levels: pre and post]. False discovery rate was controlled according to the Benjamini– 7
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Hochberg–Yekutieli method. To reveal differences between ST and DT improvements, the
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post-training values were normalized to the pre-training values and analyzed using an
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ANOVA, group [3 levels: EG, PG, CG] x task [2 levels: DT, ST]. Significant interaction
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effects were followed up with paired t-tests. The training and fall reports were analyzed with
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the Chi-square test, except for the training time, which was analyzed with the Kruskal-Wallis
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test and Mann-Whitney U post-hoc tests. The analyses were performed with SPSS 19.0 (SPSS,
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Inc., Chicago, IL).
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Most of the statistical tests showed significant improvements in the recorded balance and gait
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parameters, as indicated by the significant main effect of time, see tables 1, 2 and 3. None of
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the balance tests showed a significant group x time interaction effect, i.e., all three groups
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showed similar improvements after the training. However, when comparing the step-to-step
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variability improvements during ST to those during DT (see figure 1), a significant group x
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task interaction was evident (F(2,52)=9.3, p
