**4. Results and discussions**

#### **4.1 Association of muscle contraction to relaxation**

On comparing the muscle activation and relaxation scores across all subjects in Trial 1 (168 sessions) and Trial 2 (total 120 sessions), it was seen that successful

performance of higher repetitions of muscle contractions above an EMG threshold was associated with the ability to volitionally relax those muscles below an EMG threshold immediately after contraction (Trial 1: Pearson's coefficient = 0.78, CI = 99%; Trial 2: Pearson's coefficient = 0.74, CI = 99%).

Subjects who were unable to relax, volitionally, in a consistent manner had difficulties in performing simple actions such as extensions and flexions repeatedly as well as tasks. The antagonist was observed to be relatively stronger (the gray koala bear climbed higher up on the tree) in most subjects at week 0, whenever the subjects tried to activate the agonist and raise the golden koala bear up the tree. These subjects also demonstrated an inability to relax a muscle immediately on completion of a movement or task.

#### **4.2 Clinical scale outcomes**

The outcomes based on the FMA and ARAT clinical scales for both the trials are summarized in **Table 2**. Subjects have been categorized into mildly- (55–57), moderately- (32–54) and severely-impaired (≤31) based on their FMA scores at week 0. Subject LH006 encountered a personal accident at home resulting in a head injury during the study and was discontinued from the trial.

The scores for both the assessment scales were reduced to a common denominator by normalizing assessment scores against full scores of the respective scale. For FMA and ARAT, the full scores are 66 and 57 respectively.

Based on the nominalized scores, the percentage improvement in both the functional scales for the subjects in Trial 1 and Trial 2 can be summarized as shown in **Table 3**. Since these improvements are based on initial measurements of level of impairment (week 0), they capture both clinical and sub-clinical performance changes or incremental improvements or decline achieved by the subjects. The estimated minimum clinically important difference (MCID) of the upper limb FMA scores ranges from 4.25 to 7.25 points depending on the different facets of upper limb movement (overall upper limb function MCID is 5.25) while the MCID values for the ARAT were 5.7 points for chronic stroke patients [41, 42]. In Trial 1, there were two subjects who achieved MCIDs in FMA; RH003 (8 points) and RH007 (9 points) and four subjects who achieved MCIDs in ARAT; RH005 (7 points), LH005 (7 points), LH007 (12 points), LH003 (6 points). In Trial 2, subjects NRH006 (13 points), NLH003 (6 points), NRH001 (7 points) and NRH003 (6 points) achieved MCIDs in ARAT. These MCIDs were achieved with only 5–10 repetitions per exercise per session, which is about 10–30% of the number of exercise repetitions recommended per session in standard care.

Training in self-regulation of antagonist muscle relaxation during movement using the SynPhNe system contributed to positive pre-post changes in FMA (Trial 1: Mean = 6.855%, SD = 7.85; Trial 2: Mean = 5.05%, SD = 6.00) and ARAT (Trial 1: Mean = 25.84%, SD = 49.86; Trial 2: Mean = 30.17%, SD = 21.20).

#### **4.3 Discussions**

Results from the two separate trials are presented to illustrate the degree of consistency in two different patient samples. The inclusion and exclusion criteria in both studies were similar. However, in Trial 1 therapists fully supervised the therapy sessions while in Trial 2 non-therapists conducted the sessions. In both studies, a separate team of blinded therapists performed the pre- and post-assessments. Neither study reported any adverse events.

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**Table 2.**

*Restoring Independent Living after Disability Using a Wearable Device: A Synergistic…*

Mild RH001 58 60 53 57 Moderate RH003 36 44 9 11

Severe RH002 16 19 6 7

Mean 39.43 41.93 21.79 25.07 Std. dev 11.86 12.67 15.10 16.64

Moderate NRH006 54 56 38 51

Severe NRH005 31 30 9 10

Mean 34.90 36.40 17.30 22.00 Std. dev 9.78 9.69 10.31 13.05

**Fugl Meyer (FMA)**

**Action research arm test (ARAT)**

**W0 W4 W0 W4**

RH005 45 46 20 27 RH007 50 59 45 49 LH001 35 33 5 5 LH002 44 45 25 28 LH004 45 44 21 21 LH005 52 56 32 39 LH007 50 52 32 44 LH008 43 47 32 32

RH004 27 27 5 5 RH006 29 31 17 17 LH003 22 24 3 9

NLH003 43 42 17 23 NLH002 38 41 25 28 NRH001 38 40 18 25 NRH007 37 39 21 26 NRH004 37 39 27 31 NRH003 32 33 7 13

NRH002 20 24 8 9 NLH001 19 20 3 4

**code**

**Figure 7** supported the research group's direction that both activation and relaxation must be trained specifically, as opposed to a pre-occupation with repeated

Both the studies reported a larger increase in ARAT scores as compared to FMA scores. This increase in ARAT was not necessarily linked to those who had high FMA scores at week 0. This suggests that functional task performance and object manipulation ability may improve even though reduction of impairment at a gross

muscle activation alone as is common in rehabilitation [43].

*FMA and ARAT clinical scores at week 0 (W0) and week 4 (W4).*

*DOI: http://dx.doi.org/10.5772/intechopen.86011*

**Impairment level Subject** 

Clinical outcomes in Trial 1

Clinical outcomes in Trial 2


*Restoring Independent Living after Disability Using a Wearable Device: A Synergistic… DOI: http://dx.doi.org/10.5772/intechopen.86011*

#### **Table 2.**

*Assistive and Rehabilitation Engineering*

of a movement or task.

**4.2 Clinical scale outcomes**

performance of higher repetitions of muscle contractions above an EMG threshold was associated with the ability to volitionally relax those muscles below an EMG threshold immediately after contraction (Trial 1: Pearson's coefficient = 0.78,

Subjects who were unable to relax, volitionally, in a consistent manner had difficulties in performing simple actions such as extensions and flexions repeatedly as well as tasks. The antagonist was observed to be relatively stronger (the gray koala bear climbed higher up on the tree) in most subjects at week 0, whenever the subjects tried to activate the agonist and raise the golden koala bear up the tree. These subjects also demonstrated an inability to relax a muscle immediately on completion

The outcomes based on the FMA and ARAT clinical scales for both the trials are summarized in **Table 2**. Subjects have been categorized into mildly- (55–57), moderately- (32–54) and severely-impaired (≤31) based on their FMA scores at week 0. Subject LH006 encountered a personal accident at home resulting in a head

The scores for both the assessment scales were reduced to a common denominator by normalizing assessment scores against full scores of the respective scale. For

Based on the nominalized scores, the percentage improvement in both the functional scales for the subjects in Trial 1 and Trial 2 can be summarized as shown in **Table 3**. Since these improvements are based on initial measurements of level of impairment (week 0), they capture both clinical and sub-clinical performance changes or incremental improvements or decline achieved by the subjects. The estimated minimum clinically important difference (MCID) of the upper limb FMA scores ranges from 4.25 to 7.25 points depending on the different facets of upper limb movement (overall upper limb function MCID is 5.25) while the MCID values for the ARAT were 5.7 points for chronic stroke patients [41, 42]. In Trial 1, there were two subjects who achieved MCIDs in FMA; RH003 (8 points) and RH007 (9 points) and four subjects who achieved MCIDs in ARAT; RH005 (7 points), LH005 (7 points), LH007 (12 points), LH003 (6 points). In Trial 2, subjects NRH006 (13 points), NLH003 (6 points), NRH001 (7 points) and NRH003 (6 points) achieved MCIDs in ARAT. These MCIDs were achieved with only 5–10 repetitions per exercise per session, which is about 10–30% of the number of exercise repetitions recommended per session

Training in self-regulation of antagonist muscle relaxation during movement

using the SynPhNe system contributed to positive pre-post changes in FMA (Trial 1: Mean = 6.855%, SD = 7.85; Trial 2: Mean = 5.05%, SD = 6.00) and ARAT (Trial 1: Mean = 25.84%, SD = 49.86; Trial 2: Mean = 30.17%, SD = 21.20).

Results from the two separate trials are presented to illustrate the degree of consistency in two different patient samples. The inclusion and exclusion criteria in both studies were similar. However, in Trial 1 therapists fully supervised the therapy sessions while in Trial 2 non-therapists conducted the sessions. In both studies, a separate team of blinded therapists performed the pre- and post-assessments.

CI = 99%; Trial 2: Pearson's coefficient = 0.74, CI = 99%).

injury during the study and was discontinued from the trial.

FMA and ARAT, the full scores are 66 and 57 respectively.

**126**

in standard care.

**4.3 Discussions**

Neither study reported any adverse events.

*FMA and ARAT clinical scores at week 0 (W0) and week 4 (W4).*

**Figure 7** supported the research group's direction that both activation and relaxation must be trained specifically, as opposed to a pre-occupation with repeated muscle activation alone as is common in rehabilitation [43].

Both the studies reported a larger increase in ARAT scores as compared to FMA scores. This increase in ARAT was not necessarily linked to those who had high FMA scores at week 0. This suggests that functional task performance and object manipulation ability may improve even though reduction of impairment at a gross


#### **Table 3.**

*Percentage improvement post-therapy (week 4) with respect to pre-therapy.*

level is proportionately lower. Subjects who achieved MCIDs did so mostly in ARAT and not FMA, which is somewhat counter-intuitive. This may be because several functional tasks do not demand a full range of motion, e.g., Eating with chopsticks or Picking up a small object like a pen with a two-finger pinch. In the experience of the study team, it was noted that subjects were more motivated attempting to do actual functional tasks such as opening a book and manipulating chopsticks as compared to standard joint extension/flexion exercises that were repetitive and not directly linked to a perceived functional outcome. It may be noted that each exercise

**129**

*Restoring Independent Living after Disability Using a Wearable Device: A Synergistic…*

and activity was repeated only 5–10 times per session to produce the outcomes reported, which was about a fifth of the number usually recommended in rehabilitation settings, and about a tenth or less of that in high repetition therapy. This was done to ensure that compensatory strategies did not set in due to fatigue, boredom, or distraction. The results raise some questions about initial functional results being dependent on high repetitions and are, in fact, reminiscent about how babies learn with few, non-similar repetitions [29]. Since both studies exclusively recruited patients who were both chronic and plateaued, the chances of spontaneous recovery were minimized, although cannot be ruled out. The authors are of the opinion that restoration of function resembling spontaneous recovery may, in fact, be facilitated in the chronic phase of therapy by the re-learning of such brain and muscle strategies as described in these experiments, enhancement of relaxation and attention

*Muscle activation is associated with relaxation during repetitive practice in (A) Trial 1 (B) Trial 2.*

The gold standard for restoration of function and independence is still conventional, manual therapy. Kollen et al. reviewed more than 700 published studies and concluded that conventional robotic or stimulation treatment approaches induce improvements that are confined to impairment level only and do not generalize to functional improvement [2]. They stated that treatment strategies that incorporate a strong emphasis on functional training and task-specific therapy may hold the key to optimal stroke therapy. A search of systematic reviews in the Cochrane and other databases on well-known approaches such as electro-mechanical and robot-assisted arm training, electro-stimulation and EMG triggered neuromuscular stimulation of wrist and fingers showed that only electro-stimulation held certain advantages over conventional, manual therapy when comparing outcomes for motor ability [44–48]. However, conventional therapy continues to be superior in improving the complete spectrum ranging from gross motor, fine motor, strength, dexterity and ability to manipulate objects and perform timed tasks. Hence, the authors of this paper carried out a follow-up study with 30 subjects, comparing a group undergoing SynPhNe training to a group receiving standard care, which was a mix of conventional physiotherapy, physical therapy, occupational therapy and neuro therapy. Since the goal is to develop a system which can augment therapy effectively at home, the study was designed to prove that SynPhNe treatment was comparable to standard care. The results of this study have been published previously [49]. The conclusion was that SynPhNe training

was comparable to standard care as seen in the FMA and ARAT scales.

The EMG data demonstrated that the stroke subjects had hitherto unknown antagonist over-activation in wrist and finger movements, which were moderated and subdued by starting the exercises with a reduced range of motion and reduced speed.

*DOI: http://dx.doi.org/10.5772/intechopen.86011*

**Figure 7.**

and the progressive reduction of compensation.

*Restoring Independent Living after Disability Using a Wearable Device: A Synergistic… DOI: http://dx.doi.org/10.5772/intechopen.86011*

**Figure 7.**

*Assistive and Rehabilitation Engineering*

Percentage improvement in Trial 1

Percentage improvement in Trial 2

**Subject code Fugl Meyer** 

**(FMA)**

RH001 3.45 7.55 RH002 18.75 16.67 RH003 22.22 22.22 RH004 0.00 0.00 RH005 2.22 35.00 RH006 6.90 0.00 RH007 18.00 8.89 LH001 −5.71 0.00 LH002 2.27 12.00 LH003 9.09 200.00 LH004 −2.22 0.00 LH005 7.69 21.88 LH007 4.00 37.50 LH008 9.30 0.00 Mean 6.85 25.84 Std. dev 7.85 49.87

NRH001 5.26 38.89 NRH002 20 12.5 NRH003 3.13 85.71 NRH004 5.41 14.81 NRH005 −3.23 11.11 NRH006 3.7 34.21 NRH007 5.41 23.81 NLH001 5.26 33.33 NLH002 7.89 12 NLH003 −2.33 35.29 Mean 5.05 30.17 Std. dev 5.72 20.22

**Action research arm test (ARAT)**

**128**

**Table 3.**

level is proportionately lower. Subjects who achieved MCIDs did so mostly in ARAT and not FMA, which is somewhat counter-intuitive. This may be because several functional tasks do not demand a full range of motion, e.g., Eating with chopsticks or Picking up a small object like a pen with a two-finger pinch. In the experience of the study team, it was noted that subjects were more motivated attempting to do actual functional tasks such as opening a book and manipulating chopsticks as compared to standard joint extension/flexion exercises that were repetitive and not directly linked to a perceived functional outcome. It may be noted that each exercise

*Percentage improvement post-therapy (week 4) with respect to pre-therapy.*

*Muscle activation is associated with relaxation during repetitive practice in (A) Trial 1 (B) Trial 2.*

and activity was repeated only 5–10 times per session to produce the outcomes reported, which was about a fifth of the number usually recommended in rehabilitation settings, and about a tenth or less of that in high repetition therapy. This was done to ensure that compensatory strategies did not set in due to fatigue, boredom, or distraction. The results raise some questions about initial functional results being dependent on high repetitions and are, in fact, reminiscent about how babies learn with few, non-similar repetitions [29]. Since both studies exclusively recruited patients who were both chronic and plateaued, the chances of spontaneous recovery were minimized, although cannot be ruled out. The authors are of the opinion that restoration of function resembling spontaneous recovery may, in fact, be facilitated in the chronic phase of therapy by the re-learning of such brain and muscle strategies as described in these experiments, enhancement of relaxation and attention and the progressive reduction of compensation.

The gold standard for restoration of function and independence is still conventional, manual therapy. Kollen et al. reviewed more than 700 published studies and concluded that conventional robotic or stimulation treatment approaches induce improvements that are confined to impairment level only and do not generalize to functional improvement [2]. They stated that treatment strategies that incorporate a strong emphasis on functional training and task-specific therapy may hold the key to optimal stroke therapy. A search of systematic reviews in the Cochrane and other databases on well-known approaches such as electro-mechanical and robot-assisted arm training, electro-stimulation and EMG triggered neuromuscular stimulation of wrist and fingers showed that only electro-stimulation held certain advantages over conventional, manual therapy when comparing outcomes for motor ability [44–48]. However, conventional therapy continues to be superior in improving the complete spectrum ranging from gross motor, fine motor, strength, dexterity and ability to manipulate objects and perform timed tasks. Hence, the authors of this paper carried out a follow-up study with 30 subjects, comparing a group undergoing SynPhNe training to a group receiving standard care, which was a mix of conventional physiotherapy, physical therapy, occupational therapy and neuro therapy. Since the goal is to develop a system which can augment therapy effectively at home, the study was designed to prove that SynPhNe treatment was comparable to standard care. The results of this study have been published previously [49]. The conclusion was that SynPhNe training was comparable to standard care as seen in the FMA and ARAT scales.

The EMG data demonstrated that the stroke subjects had hitherto unknown antagonist over-activation in wrist and finger movements, which were moderated and subdued by starting the exercises with a reduced range of motion and reduced speed.

Once the antagonist activity was subdued and reinforced over 2–4 sessions, the range of motion and speed was progressively increased in subsequent sessions. This was effective particularly in wrist and finger extension, which is known to be a significant challenge for most stroke patients. Control deficiencies in approach, sequential steps and object release were similarly improved with slower execution speeds that were meant to effect better proximal stabilization and reduced compensation as often seen in shoulder elevation and abduction while reaching, pronating, and grasping with the affected arm. Since the most significant improvements in percentage terms were seen in the ARAT scale which evaluates functional and participation tasks, the authors propose that the SynPhNe system impacts independence positively, combined with enhanced self-regulation and the self-use of technology.

All subjects tolerated the multi-modal feedback well and did not report feeling overwhelmed by the user interface and demands of the feedforward-feedback loop. It was noticed that the distribution of the visual sampling of the feedforward and feedback during the sessions differed between subjects and within subjects as therapy sessions progressed. This could be an interesting area of investigation in future studies to better understand how adults learn in a non-instructional and sensory manner. This paradigm needs to be tested further with a larger study and a 30–60 day follow-up to evaluate retention of brain-muscle strategies learnt and further generalizations to other functional activities. Two larger, case-controlled studies are underway presently with sub-acute and chronic phase patients to understand how the transition from hospital to home-based therapy may be executed using the SynPhNe system, and the effect on outcomes and independence.

## **5. Conclusion**

Training to relax specific muscles adequately and in a timely manner during therapy using a feedforward-feedback loop, instead of practicing repetitive muscle contraction alone, may help re-learn movement and daily functional activities in stroke subjects who have "plateaued" and not responding to further therapy.

Simultaneous activation-relaxation training of agonist-antagonist not only facilitated improvement of functional abilities but was also well tolerated by all subjects and did not cause them to get overwhelmed by the number of feedforward and feedback elements on the computer screen. This indicated that despite the challenges brought on by stroke, patients with impairments can still leverage their sensory learning abilities in an exploratory and then goal-directed manner while attempting to regain spatial and temporal aspects of movement and function of the upper limb. Thus, they appeared to be able to re-boot how they learnt in a sensory manner as babies using the feedforward-feedback modality. A wearable device such as the SynPhNe system may, therefore, help leverage neuroplasticity and act as a key complement to conventional therapy. Being patient-led and requiring reduced therapist supervision, it can effectively augment therapy hours at home or in the community, thus holding the promise of making daily therapy accessible and affordable to all.
