MILITARY MEDICINE, 182, 7/8:e1963, 2017

Case Report on the Use of a Custom Myoelectric
Elbow–Wrist–Hand Orthosis for the Remediation of Upper
Extremity Paresis and Loss of Function in Chronic Stroke
Stefanie Dunaway, MS OTR/L*; D. Brianna Dezsi, OTD, OTR/L†; Jessica Perkins, COTA/L†;
Daniel Tran, MD†; Jonathan Naft, CPO*

INTRODUCTION
Myoelectric control was first introduced for prosthetics in
1945,1 and since that time has been heavily researched in the
United States under military funding. It became prevalent during the Vietnam War and in subsequent years, when casualties
returned needing prosthetic limbs. Today, myoelectrically controlled prosthetics are prescribed for individuals with upper
limb amputations. Custom fabricated, myoelectric orthoses
are now also being provided to civilians, veterans, and active
duty personnel with intact, but impaired upper extremities due
to neuromuscular damage such as stroke, incomplete spinal
cord injury, brachial plexus injuries or traumatic brain injury
(TBI). Prior research conducted on these devices demonstrated that users of myoelectric devices increased their independence in a wide range of activities of daily living (ADLs)
and instrumental activities of daily living (IADLs).2–5
Every year in the United States, approximately 795,000
people, (civilians, active military, and veterans) experience a
stroke6 of which 40% exhibit chronic disability including upper
extremity (UE) impairments such as paresis and spasticity.
Additionally, within the military, over 350,000 U.S. personnel
have been diagnosed with a traumatic brain injury since 2000.7
*Myomo Inc., One Broadway 14th floor, Cambridge, MA 02142.
†Louis Stokes Cleveland Veteran Affairs Medical Center, 10701 East
Boulevard, Cleveland, OH 44106.
© AMSUS – The Society of Federal Health Professionals, 2017
doi: 10.7205/MILMED-D-16-00399

MILITARY MEDICINE, Vol. 182, July/August 2017

Survivors who undergo traditional rehabilitative therapies, are
frequently left with chronic UE impairments and an associated
loss of function, dependence on caregivers, and decreased
quality of life. Custom fabricated myoelectric orthoses
may provide an alternative solution and an adjunct to traditional therapies for those with hemiparesis and loss of UE
function. It is the aim of this case report to describe the
functional and rehabilitative outcomes of a veteran with one
such custom myoelectric orthosis.
The myoelectric orthosis used for this case report is called
the MyoPro®. The Myopro® (Myomo Inc., Cambridge,
Massachusetts) is a custom fabricated myoelectric elbow–
wrist–hand orthosis (MEWHO) currently available in numerous Veteran Affairs facilities across the nation, as well as to
civilian facilities. Surface sensors—built into the upper cuff of
the orthosis and located over the bicep and tricep muscles—
detect the user’s electromyographic (EMG) signal once he/she
initiates a muscle contraction. The EMG signal is filtered
through patented software onboard the orthosis and this
activates the motor to move the elbow in the desired direction.
Movement is proportional to muscle output and EMG
amplitude. An additional set of sensors are positioned over the
distal forearm which registers EMG activity from both wrist
and finger flexors/extensors. EMG output from the forearm
sensors power a second motor to open and close the fingers
in a 3 jaw-chuck grip pattern, upon user initiation. The treating
clinician is able to amplify the user’s EMG signal and
customize the level of assistance provided by the orthosis to
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ABSTRACT Introduction: This case study describes the application of a commercially available, custom myoelectric
elbow–wrist–hand orthosis (MEWHO), on a veteran diagnosed with chronic stroke with residual left hemiparesis. The
MEWHO provides powered active assistance for elbow flexion/extension and 3 jaw chuck grip. It is a noninvasive orthosis
that is driven by the user’s electromyographic signal. Experience with the MEWHO and associated outcomes are reported.
Materials and Methods: The participant completed 21 outpatient occupational therapy sessions that incorporated the use
of a custom MEWHO without grasp capability into traditional occupational therapy interventions. He then upgraded to
an advanced version of that MEWHO that incorporated grasp capability and completed an additional 14 sessions. Range
of motion, strength, spasticity (Modified Ashworth Scale [MAS]), the Box and Blocks test, the Fugl–Meyer assessment
and observation of functional tasks were used to track progress. The participant also completed a home log and a
manufacturers’ survey to track usage and user satisfaction over a 6-month period. Results: Active left upper extremity
range of motion and strength increased significantly (both with and without the MEWHO) and tone decreased,
demonstrating both a training and an assistive effect. The participant also demonstrated an improved ability to incorporate
his affected extremity (with the MEWHO) into a wide variety of bilateral, gross motor activities of daily living such as
carrying a laundry basket, lifting heavy objects (e.g. a chair), using a tape measure, meal preparation, and opening doors.
Conclusion: Custom myoelectric orthoses offer an exciting opportunity for individuals diagnosed with a variety of
neurological conditions to make advancements toward their recovery and independence, and warrant further research into
their training effects as well as their use as assistive devices.

Case Report

At the time of starting to use the MEWHO with grasp, the
participant presented with unresolved UE deficits in range of
motion (ROM), strength, fine and gross motor skills, and
functional use of the paretic left arm.

MEWHO with grasp.

move the paretic limb. The clinician is also able to select
whether the orthosis moves based on activity from a single or
multiple muscle groups, tailored to the user’s clinical presentation. The orthosis weighs approximately 4 lbs and provides
0 to 130 degrees of motion and 7 Nm of torque at the elbow
and 1–2.7 Nm torque for the fingers (Fig. 1). This translates
into the ability to lift approximately 5–8 lbs (depending on
the user’s clinical presentation).
CASE DESCRIPTION
The participant is a 62-year-old veteran, who served in the
U.S. Marines Corps as a Corporal and in the U.S. Navy as a
Seaman. He was awarded the Purple Heart medal as a result of
a combat injury during his service in the Vietnam War. He is
a right-hand-dominant male who presented with dysarthria and
left hemiplegia in December 2013 due to an infarct of the
posterior limb of the right internal capsule. Past medical history
is positive for hypertension, tobacco use, a previous transient
ischemic attack in 2010, hyperlipidemia, and a left Bell’s Palsy
in 2013. Immediately following his stroke in 2013, the
participant completed an inpatient rehabilitation stay during
which he received traditional occupational therapy (OT) for
1 hour a day. The participant began outpatient OT in January
2014 to treat the ongoing functional deficits associated with
his left hemiparesis, where he was prescribed a custom
MEWHO (without grasp capability) in April 2014. The
participant met the criteria for the MEWHO including intact
cognition, no UE contractures, and sufficient EMG signal
strength in his bicep and tricep to power the orthosis.
Measurements and a cast were taken of his affected arm
and a custom MEWHO was manufactured. The participant
continued to participate in OT with his orthosis until August
2014, at which point he was reevaluated for the advanced
model that includes additional myoelectric grasp capabilities.
The participant received his upgraded orthosis in November
2014. At this time, the overall fit and comfort of the device
was assessed, appropriate sensor locations were found, and
the device was programmed with the appropriate level of
assistance using the manufacturers programming software.
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RESULTS
Active left UE ROM and strength both increased (Table II).
He also demonstrated an improved ability to incorporate his
affected extremity (while wearing his orthosis) into a wide
variety of bilateral, gross motor ADLs and IADLs such as
carrying a laundry basket (Fig. 2), lifting heavy objects (e.g.
a chair), using a tape measure, meal preparation, and opening
doors. To demonstrate the specific improvements in grasp and
release while wearing the MEWHO with grasp, the following
data points illustrate how the participant continued to lack
active hand function until that time (November 2014).
However, once the orthosis had been donned, the participant
was able to achieve an immediate active and functional grip
pattern. Furthermore, these data points demonstrate the
presence of both a training and a rehabilitative effect of using
the MEWHO over time, as the participant was able to
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FIGURE 1.

METHODS
The participant completed a total of 21, 1-hour outpatient OT
sessions that began with traditional OT interventions for
3 months, such as functional electrical stimulation, mirror
therapy, dynataping, massage wand, fluidotherapy, proprioceptive neuromuscular facilitation, therapeutic exercise, activeassisted and passive ROM, and task-oriented/occupation-based
interventions. He and his therapist then incorporated the
custom MEWHO without grasp into his plan of care, upon
delivery in April 2014. The participant received training in
proficient use of the orthosis: donning/doffing technique,
repetitive task practice drills, and application of the orthosis
during multistep functional tasks such as meal preparation. He
was also given a home activity plan and a wearing schedule,
beginning at 30 minutes daily, to increase endurance and
facilitate functional use of his affected extremity. After
upgrading to the custom MEWHO with grasp in November
2014, the participant completed an additional 14 sessions under
the supervision of his therapist and fitting prosthetist. These
sessions were dedicated to mastering the operation of the new
orthosis and utilizing it during daily functional tasks such as
self-feeding, drinking from a cup, carrying a laundry basket.
A progressive, functional training protocol from the orthosis
manufacturer was incorporated at this time (Table I). The
participant also completed an online manufacturers’ survey to
track usage and user satisfaction for 6 months. Outcome testing
throughout treatment included ROM testing, strength (Manual
Muscle Testing [MMT]), and the Modified Ashworth Scale
(MAS)8 to assess spasticity and functional task assessment.
Once the participant upgraded to the MEWHO with grasp, the
Fugl–Meyer9 assessment was also utilized to quantify progress.

Case Report
TABLE I.

MEWHO With Grasp Training Protocol

Elbow–bicep mode

Maintaining arm in relaxed position
during ambulation

Treatment Phase
MEWHO Proficiency Training and
Motor Learning/Sequencing
Basic Task Training

Advanced Functional
Task Training

Treatment Activities

Hand–open mode
Elbow–bicep and
tricep modes
Hand–open and
close modes
Elbow–dual mode
Hand–dual mode

Hand to mouth tasks, e.g., bringing
cup or food up to mouth
Grasping beanbags and releasing
into buckets
Bilateral feeding task

Functional use of grasp/release
Functional use of elbow and hand movements
in multi-step ADLs, IADLs

Date: 12/7/2014

Active Open at hand: 0% without orthosis
with grasp, Full (100%) open with orthosis
Date: 1/29/2016 Active Open at hand: 75% without orthosis,
Full (100%) open with orthosis
These results demonstrate how working with a custom
MEWHO may have contributed to the remediation of UE
deficits, in particular elbow, wrist, and hand function. The
participant also demonstrated substantial improvements in daily
functional use of his paretic left arm, and an increase in his
overall level of independence both at home and in his
community. While wearing the MEWHO, the participant was
able to use his left arm to carry weighted objects bilaterally,
to stabilize objects such as a cup or plate during use, and
to put items away in overhead cabinets. Independence
also increased with household chores such as laundry, meal
preparation, and light cleaning tasks. Information from the
manufacturers’ survey and home log (September 2015–March
2016) show that the participant was able to complete additional
tasks such as sweeping/mopping the floor, washing and folding
clothes, and moving/lifting chairs. During this 6-month
timeframe, the participant logged 25 entries and wore his
orthosis at home for a total of 34 hours. The participant wore
his orthosis between 30 minutes and 2 hours each time and
reported an average satisfaction rating of 8.78/10 (0 = not
satisfied at all, 10 = extremely satisfied). Overall, the participant reported a high level of satisfaction, improvement in his
quality of life, and increased functionality of his paretic arm.
He also reported a few areas for improvement. These included
addressing technical glitches such as sensor and electronic
malfunctions, decreasing the weight and bulk of the orthosis
(4 lbs); redesigning the harness, increasing the battery life (it is
currently 2 hours), and making the orthosis waterproof so he
could wear it outside during wet conditions. Battery life and
fatigue were the most common reasons for needing to stop use
of the orthosis. The participant was able to self-don his orthosis
independently in 3 to 5 minutes, but he did express the need

to practice and that it was difficult when he first tried to do it
alone. Interestingly, the participant noted that if he stops using
his orthosis for longer than 2 days, his arm—in particular his
hand and fingers—begin to stiffen and cause discomfort, and
he loses ROM and function.
DISCUSSION
Regular and consistent use of the custom MEWHO in conjunction with traditional OT has resulted in many benefits and
positive functional outcomes for the participant. The orthosis
was shown to provide both assistive device benefits as well
as rehabilitative benefits. While wearing his orthosis, he is able
to be more independent with daily ADLs and IADLs such as
meal preparation, folding and washing clothes, accessing items
in overheard cabinets, bilateral lifting tasks (e.g. laundry
basket, dining chair), sweeping/mopping and stabilizing objects
such as cups and plates. Once fitted with the MEWHO with
grasp, the participant demonstrated additional improvement in
his affected hand function in particular, again both with and
without the orthosis donned. Consistent use of this myoelectric
orthosis over time has also resulted in improvements in the
ROM and strength and a reduction of spasticity in his paretic
arm. The participant’s comment that not using his orthosis with
grasp for longer than 2 days results in his arm and hand
stiffening and losing function, suggests that the changes he
has experienced in his arm are potentially due to the integration
of the orthosis into his therapy regime. Looking at the data
from November 2014 onward (in particular March 2015–
October 2015), we see improvements in gross grasp, lateral
pinch strength, wrist ROM, and emerging ulnar and radial
deviation. With this newfound hand function and increased
UE strength overall, the participant demonstrates competence with tasks such as opening doors and cupboards with
his affected hand, as well as using a measuring tape, picking a phone off the hook, and holding papers, all without
using the orthosis. Results from the Fugl–Meyer assessment
(Table III)—specifically in the wrist, hand and coordination/
speed categories—also indicate a training effect and remediation of UE paresis.
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Carrying laundry basket
Drying dishes
Sweeping

independently open his hand (75%) by January 2016, without
assistance from the MEWHO:

MILITARY MEDICINE, Vol. 182, July/August 2017

Objective
Volitional relaxation of spastic muscles;
improved motor control and isolation
Proficiency with orthosis
Functional use of elbow flexion/extension

MILITARY MEDICINE, Vol. 182, July/August 2017

NT
September 2014

May 2014
(MyoPro Classic)

September 2014

May 2014
(MyoPro Classic)

January 2014

NT, Not Tested; WFL, Within Functional Limits.

Spasticity (Modified Ashworth Scale)
Elbow Flex
1+
Elbow Ext
1+
Wrist Flex
1+
Wrist Ext
1+ With
2 Beats Clonus

3-/5
36 lbs
NT

3-/5
31 lbs
NT

3-/5
21 lbs
NT

1
0
0
1

0
0
0
1

3-/5

Hand
Grip (L Hand)
Lateral Pinch

3-/5

3-/5

3-/5
3-/5

Wrist

3-/5
3-/5

November 2014
(MyoPro Motion G)

NT

50

3-/5
3-/5

45

WFL (Supine)
WFL (Supine)
NT
20

120 (Seated With
Compensation)
82 (Seated With
Compensation)
125 (Seated)
−20 (Seated)
60/40
20

November 2014
(MyoPro Motion G)

Strength (MMT)
Shoulder
Elbow

Radial/Ulnar Deviation

Wrist Ext

97 (Seated)
−30 (Seated)
NT
20 With
Gravity Assist
40 With
Compensation
NT

Elbow Flex
Elbow Ext
Supination/Pronation
Wrist Flex

105 (Supine)

90 (Supine)

Shoulder abd/add

133 (Supine)

91 (Supine)

Active ROM (Degrees)
Shoulder Flex

September 2014

3-/5
40 lbs
NT

3-/5

3-/5
3-/5

January 2015

0
0
0
0

November 2014
(MyoPro Motion G)

NT

60

125
−20
NT
35

120 (Seated With
Compensation)
82

January 2015

NT
NT
NT
NT

0
0
0
1 With Clonus

NT
NT
NT

NT

4/5
4/5

0
0
0
0

March 2016

NT

NT

WFL
WFL
NT
NT

WFL

WFL

March 2016

March 2016

March 2015

15/30

70

WFL
WFL
NT
55

WFL

WFL

May 2015

January 2015

3-/5
3/5
Pro/Sup 3/5
Flex 3-/5
Ext 3/5
2-/5
47 lbs
11 lbs

March 2015

NT

65

130
0
60/Full
40

120/Full

155

March 2015

ROM, Strength (MMT), and Spasticity (MAS) Results Completed Without the Orthosis

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May 2014
(MyoPro Classic)

TABLE II.

Case Report

Case Report

patients receive an average of 47 minutes a day in OT, of
which only 4 to 11 minutes are spent on UE rehabilitation.12
Fitting patients with a custom MEWHO may be an effective
method of providing intensive UE treatment, facilitating motor
recovery, and improving the user’s independence with
practiced tasks.

Carrying a laundry basket with the EWHO.

Since the participant also engaged in traditional OT
simultaneously, it should be noted that it is challenging to
separate the progress made by traditional therapy alone versus
the effects of the MEWHO without grasp capabilities. It is
however reasonable to conclude that incorporating a MEWHO
into a comprehensive treatment program can offer excellent results. Given the participant’s level of hand function
immediately before receiving the orthosis with grasp, it is also
reasonable to conclude that the added myoelectric grasp feature
specifically contributed directly to the participant’s significant
distal fine and gross motor recovery. It is also noteworthy
that the participant began use of the MEWHO only a few
(4) months after his stroke. He was able to incorporate the
technology during the majority of his first year post stroke and
therefore it is also a challenge to determine the specific effects
of the orthosis from the natural spontaneous recovery that
occurs during this same timeframe. What is apparent is
that the participant benefitted tremendously from the use of
the myoelectric orthosis in conjunction with traditional OT.
Previous studies have illustrated the importance of an individually tailored, progressive, high-repetition, and UE task-specific
intervention to increase stroke patient outcomes and motor
recovery.10,11 This MEWHO is portable, able to be used
in the clinic and at home, and enables the user to complete
high repetitions and functional task practice. Traditional OT
frequently falls short of these standards. For example, stroke

TABLE III.

Fugl–Meyer Assessment Results—Completed
Without the MEWHO (With Grasp)

Upper Extremity
Wrist
Hand
Coordination/Speed
Sensation
Passive Joint Motion
Joint Pain
Total Score

March 2015

March 2016

31/36
9/10
9/14
3/6
11/12
24/24
24/24
111/126

31/36
10/10
14/14
6/6
11/12
24/24
24/24
120/126

MILITARY MEDICINE, Vol. 182, July/August 2017

ACKNOWLEDGMENTS
Stefanie Dunaway and Jonathan Naft are employees of Myomo Inc.—the
manufacturer of the myoelectric brace highlighted in this case report.

REFERENCES
1. McLean L, Scott RN: The Early History of Myoelectric Control of
Prosthetic Limbs (1945–1970). In: Powered Upper Limb Prostheses.
Edited by Muzumdar A. Berlin, Germany, Springer-Verlag Berlin
Heidelberg, 2004.
2. Naft J: Use of a Myoelectric Arm Orthosis to Improve Therapeutic and
Functional Value for Patients with Severe Arm Dysfunction. Available
at http://www.oandp.org/publications/jop/2013/2013-47.pdf; accessed
September 8, 2016.
3. Page SJ, Hermann V, Levine P, Lewis E, Stein J, DePeel J: Portable
neurorobotics for the severely affected arm in chronic stroke. J Neurol
Phys Ther 2011; 35: 41–9.
4. Van der Niet O, Bongers R, Van der Sluis CK: Functionality of
i-LIMB and i-LIMB Pulse hands: case report. JRRD 2013; 50(8):
1123–8.
5. Lucas L, DiCicco Matsuoka Y: An EMG-controlled hand exoskeleton for
natural pinching. JRM 2014; 16(5): 482–8.
6. Center for Disease Control and Prevention: 2015 Stroke Facts. Available at
http://www.cdc.gov/stroke/facts.htm; accessed September 8, 2016.
7. Defense and Veterans Brain Injury Center: 2016 DoD Worldwide
Numbers for TBI. Available at http://dvbic.dcoe.mil/files/tbi-numbers/
DoD-TBI-Worldwide-Totals_2000-2016_Q1-Q2_Aug-12-2016_v1.0_508_
2016-09-20.pdf; accessed September 8, 2016.
8. Ansari NN, Nadhdi S, Arab TK, Jalaie S: The interrater and intrarater reliability of the Modified Ashworth Scale in the assessment of
muscle spasticity: limb and muscle group effect. Neurorehabilitation
2008; 23(3): 231–7.

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FIGURE 2.

CONCLUSIONS
A custom MEWHO was shown to provide this veteran with
an increased ability to move and use his affected arm in a
variety of functional tasks, in particular bilateral tasks. The
participant wears his orthosis on and off throughout the day
and reports improvements in his independence with daily
functional tasks and overall quality of life. The participant has
also demonstrated significant recovery in his affected UE
including improved active ROM at the shoulder, elbow and
hand, improved strength, and a reduction in tone. This case
report highlights both the assistive/functional benefits as well
as rehabilitative benefits of a myoelectric orthosis. These
devices offer an exciting opportunity for other individuals
diagnosed with chronic stroke, brain injury, or incomplete
spinal cord injury to make advancements toward their recovery
and independence. Additional research is warranted on the
application of custom MEWHOs in the neurorehabilitation of
our veterans and active duty personnel.

Case Report
9. Hsieh YW, Wu CY, et al: Responsiveness and validity of three outcome
measures of motor function after stroke rehabilitation. Stroke 2009; 40(4):
1386–91.
10. Birkenmeier RL, Prager EM, Lang CE: Translating animal doses of taskspecific training to people with chronic stroke in 1-hour therapy sessions:
a proof-of-concept study. Neurorehabil Neural Repair 2010; 24: 620–35.

11. Han C, Wang Q, Meng PP, Qi MZ: Effects of intensity of arm training on hemiplegic upper extremity motor recovery in stroke patients:
a randomized controlled trial. Clin Rehabil 2013; 27: 75–81.
12. Waddell K, Birkenmeier R, Moore J, Hornby T, Lang CE: Feasibility of high-repetition, task-specific training for individuals with
upper-extremity paresis. Am J Occup Ther 2014; 68: 444–53.

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MILITARY MEDICINE, Vol. 182, July/August 2017