Description　
The goal of the powered exoskeleton is to enable people who do not have volitional movement of their lower extremities to be able to fully bear weight while standing, to walk, and to navigate stairs. The devices have the potential to restore mobility and, thus, might improve functional status, quality of life, and health status for patients with spinal cord injury, multiple sclerosis, amyotrophic lateral sclerosis, Guillain-Barré syndrome, and spina bifida.

Summary of Evidence
For individuals who have lower-limb disabilities who receive a powered exoskeleton, the evidence includes 1 randomized cross-over study and several case series. Relevant outcomes are functional outcomes, quality of life, and treatment-related morbidity. At the present, evaluation of exoskeletons is limited to small studies primarily performed in institutional settings with patients who have spinal cord injury. These studies have assessed the user’s ability to perform, under close supervision, standard tasks such as the Timed Up & Go test, 6-minute walk test, and 10-meter walk test. One randomized, open-label cross-over study and a case series in patients with multiple sclerosis and spinal cord injury, respectively, assessed use of powered exoskeletons in the outpatient setting. Although these small studies indicate powered exoskeletons may be used safely in the outpatient setting, these devices require significant training, and their efficacy has been minimally evaluated. Further evaluation of users’ safety with these devices under regular conditions, including the potential to trip and fall should be assessed. Further study is needed to determine the benefits of these devices outside of the institutional setting. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

Additional Information
Not applicable

Background  
An exoskeleton is an external structure with joints and links that might be regarded as wearable robots designed around the shape and function of the human body. A powered exoskeleton, as described in this evidence review, consists of an exoskeleton-like framework worn by a person that includes a power source supplying energy for limb movement.

One type of powered lower-limb exoskeleton (e.g., ReWalk, Indego) provides user-initiated mobility based on postural information. Standing, walking, sitting, and stair up/down modes are determined by a mode selector on a wristband. ReWalk includes an array of sensors and proprietary algorithms that analyze body movements (e.g., tilt of the torso) and manipulate the motorized leg braces. The tilt sensor is used to signal the onboard computer when to take the next step. Patients using the powered exoskeleton must be able to use their hands and shoulders with forearm crutches or a walker to maintain balance. Instructions for ambulating with ReWalk¹ are to place the crutches ahead of the body, and then bend the elbows slightly, shifting weight toward the front leg, leaning toward the front leg side. The rear leg will lift slightly off of the ground and then begin to move forward. Using the crutches to straighten up will enable the rear leg to continue moving forward. The process is repeated with the other leg.

To move from a seated to standing position or vice versa, the desired movement is selected by the mode selector on the wrist. There is a 5-second delay to allow the individual to shift weight (forward for sit-to-stand and slightly backward for stand-to-sit) and to place their crutches in the correct position. If the user is not in an appropriate position, a safety mechanism will be triggered. Walking can only be enabled while standing, and the weight shift must be sufficient to move the tilt sensor and offload the back leg to allow it to swing forward. Continuous ambulation is accomplished by uninterrupted shifting onto the contralateral leg. The device can be switched to standing either via the mode selector or by not shifting weight laterally for two seconds, which triggers the safety mechanism to stop walking. Some patients have become proficient with ReWalk by the third week of training.²

Regulatory Status 
In 2014, ReWalk (ReWalk Robotics, previously Argo Medical Technologies) was granted a de novo 510(k) classification (K131798) by the U.S. Food and Drug Administration (FDA) (Class II; FDA product code: PHL). The new classification applies to this device and substantially equivalent devices of this generic type. ReWalk (current version ReWalk Personal 6.0) is the first external, powered, motorized orthosis (powered exoskeleton) used for medical purposes that is placed over a person’s paralyzed or weakened limbs for the purpose of providing ambulation. De novo classification allows novel products with moderate- or low-risk profiles and without predicates that would ordinarily require premarket approval as a Class III device to be down-classified in an expedited manner and brought to market with a special control as a Class II device.

The ReWalk is intended to enable individuals with spinal cord injury at levels T7 to L5 to perform ambulatory functions with supervision of a specially trained companion in accordance with the user assessment and training certification program. The device is also intended to enable individuals with spinal cord injury at levels T4 to T6 to perform ambulatory functions in rehabilitation institutions in accordance with the user assessment and training certification program. The ReWalk is not intended for sports or stair climbing.

Candidates for the device should have the following characteristics:

• Hands and shoulders can support crutches or a walker.
• Healthy bone density.
• Skeleton does not suffer from any fractures.
• Able to stand using a device such as a standing frame.
• In general good health.
• Height is between 160 cm and 190 cm (5'3" to 6'2").
• Weight does not exceed 100 kg (220 lb).

In 2019, the ReWalk ReStore™, a lightweight, wearable, exo-suit, was approved for rehabilitation of individuals with lower-limb disabilities due to stroke.

In 2016, Indego (Parker Hannifin) was cleared for marketing by the FDA through the 510(k) process (K152416). The FDA determined that this device was substantially equivalent to existing devices, citing ReWalk as a predicate device. Indego is “intended to enable individuals with spinal cord injury at levels T7 to L5 to perform ambulatory functions with supervision of a specially trained companion.” Indego has also received marketing clearance for use in rehabilitation institutions.

In 2016, Ekso™ and Ekso GT™ (Ekso Bionics^® Inc.) were cleared for marketing by the FDA through the 510(k) process (K143690). The ReWalk was the predicate device. Ekso is intended to perform ambulatory functions in rehabilitation institutions under the supervision of a trained physical therapist for the following populations with upper extremity motor function of at least 4/5 in both arms: individuals with hemiplegia due to stroke, individuals with spinal cord injuries at levels T4 to L5, and individuals with spinal cord injuries at levels of C7 to T3.

In 2017, Hybrid Assistive Limb (HAL™) for Medical Use (Lower Limb Type) (CYBERDYNE Inc.) was cleared for marketing by the FDA through the 510(k) process (K171909). The ReWalk was the predicate device. The HAL is intended to be used inside medical facilities while under trained medical supervision for individuals with spinal cord injury at levels C4 to L5 (American Spinal Injury Association [ASIA] Impairment Scale C, ASIA D) and T11 to L5 (ASIA A with Zones of Partial Preservation, ASIA B)

In 2020, Keeogo™ (B-Temia) exoskeleton was cleared for marketing by the FDA through the 510(k) process (K201539). The Honda^® Walking Assist Device was the predicate device. Keeogo is intended for use in patients with stroke in rehabilitation settings.

In 2021, ExoAtlet-II^® (ExoAtlet Asia Co. Ltd.) was cleared for marketing by the FDA through the 510(k) process (K201473). The Ekso/Ekso GT was the predicate device. ExoAtlet-II is intended to perform ambulatory functions in rehabilitation institutions under the supervision of a trained physical therapist for the following populations with upper extremity motor function of at least 4/5 in both arms: individuals with spinal cord injuries at levels T4 to L5, and individuals with spinal cord injuries at levels of C7 to T3 (ASIA D).

In 2022, GEMS-H^® (Samsung Electronics Co. Ltd.) was cleared for marketing by the FDA through the 510(k) process (K213452). The Honda Walking Assist Device was the predicate device. GEMS-H is intended to help assist ambulatory function in rehabilitation institutions under the supervision of a trained health care professional for individuals with stroke who have gait deficits and exhibit gait speeds of at least 0.4 m/s and are able to walk at least 10 meters with assistance from a maximum of 1 person.

In 2022, EksoNR™ (Ekso Bionics Inc.) was cleared for marketing by the FDA through the 510(k) process (K220988). EksoNR is intended to perform ambulatory functions in rehabilitation institutions under the supervision of a trained physical therapist for the following populations: individuals with multiple sclerosis (upper extremity motor function of at least 4/5 in at least 1 arm); individuals with acquired brain injury, including traumatic brain injury and stroke (upper extremity motor function of at least 4/5 in at least 1 arm); individuals with spinal cord injuries at levels T4 to L5 (upper extremity motor function of at least 4/5 in both arms), and individuals with spinal cord injuries at levels of C7 to T3 (ASIA D with upper extremity motor function of at least 4/5 in both arms).

In 2022, Atalante^® (Wandercraft SAS) was cleared for marketing by the FDA through the 510(k) process (K221859). The Indego was the predicate device. Atalante is intended to enable individuals (> 18 years of age, able to tolerate a stand-up position) with hemiplegia due to cerebrovascular accident to perform ambulatory functions and mobility exercises, hands-free, in rehabilitation institutions under the supervision of a trained operator.

FDA product code: PHL.

Related Policies
10405 Microprocessor-Controlled Prostheses for the Lower Limb
80301 Functional Neuromuscular Electrical Stimulation

Policy 
Use of powered exoskeleton for ambulation in patients with lower-limb disabilities is considered INVESTIGATIONAL.

Policy Guidelines 
Coding 
Please see the Codes table for details. 

Rationale  
Evidence reviews assess the clinical evidence to determine whether the use of technology improves the net health outcome. Broadly defined, health outcomes are the length of life, quality of life, and ability to function, including benefits and harms. Every clinical condition has specific outcomes that are important to patients and managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of technology, 2 domains are examined: the relevance, and quality and credibility. To be relevant, studies must represent 1 or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. Randomized controlled trials are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

Promotion of greater diversity and inclusion in clinical research of historically marginalized groups (e.g., people of color [African American, Asian, Black, Latino and Native American]; LGBTQIA [lesbian, gay, bisexual, transgender, queer, intersex, asexual]; women; and people with disabilities [physical and invisible]) allows policy populations to be more reflective of and findings more applicable to our diverse members. While we also strive to use inclusive language related to these groups in our policies, use of gender-specific nouns (e.g., women, men, sisters, etc.) will continue when reflective of language used in publications describing study populations.

Pre-post study designs (using patients as their own controls) are most likely to provide evidence on the effects of a powered exoskeleton on health outcomes. Outcomes of interest are the safety of the device, the effect of the exoskeleton on the ability to ambulate, and the downstream effect of ambulation on other health outcomes (e.g., bowel and bladder function, spasticity, cardiovascular health). Of importance in this severely disabled population is the impact of this technology on activities of daily living, which can promote independence and improved quality of life.

Issues that need to be assessed include the device’s performance over the longer-term when walking compared with wheelchair mobility, the user’s usual locomotion outside of the laboratory setting, and the use of different exoskeletons or the training context.³ Adverse events (e.g., falling, tripping) can impact both safety and psychological security and also need to be assessed.

Powered Exoskeleton for Ambulation
Clinical Context and Therapy Purpose
The purpose of a powered exoskeleton for ambulation is to provide a treatment option that is an alternative to or an improvement on existing therapies for patients with lower-limb disabilities. The goal of the powered exoskeleton is to enable people who do not have volitional movement of their lower extremities to bear weight fully while standing, to ambulate over ground, and to ascend and descend stairs.

The following PICO was used to select literature to inform this review.

Populations
The relevant population of interest is patients with spinal cord injury, multiple sclerosis, amyotrophic lateral sclerosis, Guillain-Barré syndrome, and spina bifida.

Interventions
The therapy being considered is powered exoskeleton systems that use posture control and are being evaluated for home use:

• The EksoGT robotic exoskeleton (now updated to EksoNR ; Ekso Bionics) is available institutionally for rehabilitation. It is undergoing testing for personal use for ambulation in several registered trials.
• The Indego powered exoskeleton (also known as the Vanderbilt exoskeleton; Parker Hannifin) is used for gait training and is now available for home use. It includes functional electrical stimulation and weighs 29 pounds.
• ReWalk Personal 6.0 (ReWalk Robotics) consists of an onboard computer, sensor array, and rechargeable batteries that power the exoskeleton, which are contained in a backpack.
• The X1 Mina^® Exoskeleton is a joint project of the National Aeronautics and Space Administration (NASA) Johnson Space Center and the Florida Institute for Human and Machine Cognition. It was developed to provide mobility for both abled and disabled users, for rehabilitation, and exercise. It weighs 26 kg (57 lb).
• Keeogo (B-Temia) exoskeleton is intended for patients with stroke in rehabilitation settings. It has been studied for personal use in the outpatient setting.

Powered exoskeleton systems that use joystick control and are being evaluated for home use include:

• REX^® (REX Bionics) is designed for clinical use in rehabilitation centers and hospitals. REX^® P is designed for personal use and does not require use of crutches or a walker for stability, leaving the user hands-free.
• WPAL^® (Wearable Power-Assist Locomotor; Fujita Health University) is designed for use with a custom walker.
• HAL (Hybrid Assistive Limb).
• Phoenix^® (SuitX).

Comparators
The following practice is currently being used to treat lower-limb disabilities: standard rehabilitation and/or assistive devices without a powered exoskeleton.

Outcomes
The general outcomes of interest are restoration of mobility, increased function, and improved health status and quality of life for wheelchair-bound patients. Some of the potential secondary health benefits associated with increased mobility include strength and cardiovascular health, decreased spasticity, improved bladder and bowel function, and psychosocial health.

Study Selection Criteria
Methodologically credible studies were selected using the following principles:

• To assess efficacy outcomes, comparative controlled prospective trials were sought, with a preference for RCTs.
• In the absence of such trials, comparative observational studies were sought, with a preference for prospective studies.
• To assess long-term outcomes and adverse events, single-arm studies that capture longer periods of follow-up and/or larger populations were sought.
• Studies with duplicative or overlapping populations were excluded.

Review of Evidence
There is limited information about the use of powered exoskeletons outside of the institutional setting. Standard measures of walking function include the Timed Up-and-Go test, which assesses the time required to get up from a chair and commence walking; the 10-meter walk test, which evaluates the time required to walk 10 meters; and the 6-minute walk test, which measures the distance walked in 6 minutes. A less used test, the timed stair test, evaluates the time it takes to ascend or descend 10 stairs and has been used in powered exoskeleton studies.

Systematic Review
A systematic review by Tamburella et al. (2022) qualitatively summarized the effects of the powered exoskeleton (Ekso, ReWalk, Indego, REX, or HAL) on walking and on secondary health outcomes in patients with spinal cord injury.⁴ A total of 41 studies (566 patients) were included, of which only 1 was an RCT (Table 1). The characteristics of the systematic review are summarized in Table 2. The average patient age was 43.58 ± 7.84 years. The study assessed the effects of the powered exoskeleton on 14 domains: walking, cardiorespiratory/metabolic responses, spasticity, balance, quality of life, human-robot interaction, robot data, bowel functionality, strength, activities of daily living, neurophysiology, sensory function, bladder functionality, and body composition/bone density. The effects of Ekso, ReWalk, Indego, REX, and HAL were analyzed in 20, 14, 4, 2, and 1 studies, respectively. Of the 41 studies, 13 reported different adverse events during training with Ekso (n = 5 studies), ReWalk (n = 5), Indego (n = 2), and HAL (n = 1). The most frequent adverse events were skin lesions, while the less frequent adverse events were extreme fatigue, falls, bone fractures, or muscle strain. The average total number of sessions across the studies ranged from 1 to 55, and 42% of studies performed 3 sessions per week. Only 2 studies (both on Ekso) compared powered exoskeleton with other interventions (i.e., conventional physical therapy). In the studies that reported follow-up, follow-up examinations were performed 4 weeks after the end of treatment (n = 3); or after 2 months (n = 1), 2 to 3 months (n = 1), and 12 to 15 months (n = 1). Table 3 summarizes the results of the systematic review. Most studies used outcome measures relating to the walking domain; walking velocity was measured per the 10-meter walking test in 18 studies and the 6-minute walk test in 13 studies. For each domain, the systematic review reported the data as "significant" if the authors of each included study reported significant changes in their published data. A major limitation of the systematic review was that all included studies were of moderate or low methodological quality level, mainly due to poor study design. Other limitations included the small, heterogeneous number of participants; variable dosage of interventions; the absence of control groups and/or follow-up assessments in many studies; and the various parameters adopted in each domain for different types of comparisons. The heterogeneity of outcome measures precluded the ability to make general conclusions on the effects of powered exoskeletons.

Table 1. Studies Included in the Systematic Review

Study	Tamburella et al. (2022)4
Chun et al. (2020)5	⚫
McIntosh et al. (2020)6	⚫
Tsai et al. (2020)7	⚫
Gagnon et al. (2019)8	⚫
Guanziroli et al. (2019)9	⚫
Khan et al. (2019)10	⚫
Kressler et al. (2019)11	⚫
Kubota et al. (2019)12	⚫
Manns et al. (2019)13	⚫
van Dijsseldonk et al. (2019)14	⚫
Alamro et al. (2018)15	⚫
Bach Baunsgaard et al. (2018)16	⚫
Baunsgaard et al. (2018)17	⚫
Cahill et al. (2018)18	⚫
Chang et al. (2018)19	⚫
Escalona et al. (2018)20	⚫
Gagnon et al. (2018)21	⚫
Juszczak et al. (2018)22	⚫
Ramanujam et al. (2018)23	⚫
Ramanujam et al. (2018)24	⚫
Sale et al. (2018)25	⚫
Tefertiller et al. (2018)26	⚫
Yatsugi et al. (2018)27	⚫
Birch et al. (2017)28	⚫
Karelis et al. (2017)29	⚫
Benson et al. (2016)30	⚫
Lonini et al. (2016)31	⚫
Platz et al. (2016)32	⚫
Sale et al. (2016)33	⚫
Stampacchia et al. (2016)34	⚫
Kozlowski et al. (2015)35	⚫
Asselin et al. (2015)2	⚫
Evans et al. (2015)36	⚫
Hartigan et al. (2015)37	⚫
Yang et al. (2015)38	⚫
Kressler et al. (2014)39	⚫
Fineberg et al. (2013)40	⚫
Kolakowsky-Hayner et al. (2013)41	⚫
Talaty et al. (2013)42	⚫
Esquenazi et al. (2012)43	⚫
Zeilig et al. (2012)1	⚫

Table 2. Systematic Review Characteristics

Study	Dates	Trials	Participants1	N (Range)	Design	Duration
Tamburella et al. (2022)4	2012 – 2020	41	Patients > 18 years of age with SCI using powered exoskeleton (Ekso, ReWalk, Indego, REX or HAL)	566 (2 to 52)	RCTs (parallel-group or cross-over design) and non-randomized trials (cohort studies, case-control, case series, pilot studies)	NR

1Trials of patients affected by spinal cord injury and other neurological conditions (e.g., multiple sclerosis, stroke) were also included if at least 50% of participants were affected by a spinal cord injury.
NR: not reported; RCT: randomized controlled trial; SCI: spinal cord injury.

Table 3. Systematic Review Results

Study	% of Studies Addressing Each Domain	% of Studies with > 1 Outcome Measure for Each Domain with Significant Improvements After Powered Exoskeleton Training
Tamburella et al. (2022)4
Domains
Walking	27	37.2
Cardiorespiratory and metabolic responses	16	13.9
Spasticity	14	6.9
Balance	12	6.9
QOL	12	6.9
Strength	6	6.9
ADL	5	6.9
Human-robot interaction	9	4.6
Robot data	8	3.8
Neurophysiology	4	3.8
Body composition and body density	1	3.8
Bowel functionality	8	2.3
Sensory function	2	0
Bladder function	2	0

ADL: activities of daily living; QOL: quality of life.

Randomized Controlled Trial
An RCT (The Veterans Health Administration Cooperative Studies Program: Powered Exoskeletons for Persons with Spinal Cord Injury [PEPSCI] Trial) was designed for the study of exoskeletal-assisted walking in the home and community environments in patients with chronic spinal cord injury.⁴⁴ Of 424 enrolled patients, 263 failed screening and were not randomized. Of the 161 randomized patients, 151 (93.8%) were male; the mean age (standard deviation) was 46.2 (13.4) years. The intervention group consisted of standard of care (wheelchair for mobility) and use of ReWalk 6.0 exoskeleton at home for 4 months, while the control group consisted of standard of care (wheelchair) only. The primary aims of the study were to demonstrate clinically meaningful net improvements in the Mental Component Summary of the Veterans Rand-36 (MCS/VR-36) and in patient-reported outcomes for the Spinal Cord Injury Quality of Life (SCI-QOL) assessment tool for the physical-medical health domain components of bladder, bowel, and pain item banks. The major secondary aim was to demonstrate a reduction in total body fat mass. Tables 4 and 5 provide a summary of the characteristics and results of the study. Study results have not been published and were obtained from ClinicalTrials.gov (see NCT02658656 in Table 9; Ongoing Clinical Trials section). Limitations of the RCT include extensive exclusion criteria (resulting in several patients failing the screening process); furthermore, the use of an exoskeleton as an intervention prevented the ability for single- or double-blinding.

Table 4. Summary of Randomized Controlled Trial Characteristics

Study	Countries	Sites	Dates	Participants	Interventions (N = 161)
					Active (n = 78)	Comparator (n = 83)
Spungen et al. (2020);44 NCT02658656	U.S.	15	2016 – 2021	Veterans or active duty military personnel > 18 years of age With traumatic or non-traumatic SCI of 6 months duration Using a wheelchair for indoor and outdoor mobility	ReWalk Personal 6.0 exoskeleton (in-home use for 4 months) + wheelchair	Wheelchair only

NCT: national clinical trial; SCI: spinal cord injury.

Table 5. Summary of Randomized Controlled Trial Results

Study	No. (%) of Patients with > 4-Point Change on the MSC/VR-36 from Baseline to 4 Months Post Intervention1	No. (%) of Patients with > 10% Decrease on the SCI-QOL PMH Domain from Baseline to 4 Months Post Intervention2	No. (%) of Patients with > 1 kg of Total Body Fat Loss from Baseline to 4 Months Post Intervention3	No. (%) of Patients with Serious Adverse Events
Spungen et al. (2020);44 NCT02658656
ReWalk Personal 6.0 + wheelchair	12 (15.4)	10 (12.8)	14 (17.9)	11 (14.1)
Wheelchair	14 (16.9)	11 (13.3)	16 (19.3)	16 (16.87)
RR	0.91	0.97	0.93
95% CI	0.45 to 1.85	0.44 to 2.15	0.49 to 1.79
p-value	.798	.935	.829

¹Possible range of the MCS/VR-36 is 0 to 100, with a higher score indicating higher mental well-being.
²The PMH score is a sum of the SCI-QOL scores from the Bladder Management Difficulties, Bowel Management Difficulties, and Pain Interference item banks; possible range of the PMH score is 110 to 253, with a lower score indicating better physical medical well-being.
³Measured by dual photon x-ray absorptiometry (DXA) scan.
CI: confidence interval; MCS/VR-36: Mental Health Component Summary of the Veterans Rand-36; NCT: national clinical trial; PMH: Physical Medical Health; RR: risk ratio; SCI-QOL: Spinal Cord Injury Quality of Life.

Randomized Crossover Trial
One small (N = 29), randomized, open-label, cross-over study evaluated the Keeogo exoskeleton for patients with multiple sclerosis.⁴⁵ The device was first used in the clinic setting followed by a 2-week at-home period. Outcomes were compared with and without the device both in-clinic and at-home. Use of the device initially decreased performance measures during training in the clinic setting, but these measures did improve after the at-home period. Tables 6 and 7 provide a summary of the characteristics and results of this trial.

Table 6. Summary of Cross-Over Trial Characteristics

Study	Countries	Sites	Dates	Participants	Interventions (N = 29)
					Active	Comparator
McGibbon et al. (2018)45	U.S., Canada	4	2015 – 2017	Ambulatory adults with MS Able to walk at least 25 m using assisted devices as needed without human assistance	Keeogo exoskeleton	No exoskeleton

m: meters; MS: multiple sclerosis.

Table 7. Summary of Cross-Over Trial Results

Study	6-Minute Walk Test (Mean [SD])1	Timed Up-and-Go (Mean [SD])1	Timed Stair Test - Up (Mean [SD])1	Timed Stair Test - Down (Mean [SD])1	Mean Steps per Day (SD)2
McGibbon et al. (2018)45	N = 29	N = 29	N = 29	N = 29	N = 29
Exoskeleton	236.8 m (100.6)	20.5 s (7.5)	17.6 s (8.8)	13.1 s (7.0)	4693.5 (2996.0)
No exoskeleton	259.5 m (100.7)	16.2 s (5.8)	12.7 s (5.9)	15.7 s (7.7)	4425.1 (2897.0)
Change (p-value)	-22.7 (.001)	4.3 ( < .001)	4.8 ( < .001)	2.6 (.002)	268.4 (.046)

¹In the clinic setting.
²In the home setting.
m: meters; s: seconds; SD: standard deviation.

Case Series
Several case series evaluating various powered exoskeletons for ambulation have been conducted primarily in the inpatient setting for spinal cord injury. These case series were included in the systematic review by Tamburella et al. (2022) discussed earlier.

One case series has been conducted to assess the use of the powered exoskeleton in the community setting. van Dijsseldonk et al. (2020) assessed the use of ReWalk Personal 6.0 exoskeleton in the community setting for up to 3 weeks of use.⁴⁶ Table 8 summarizes the characteristics of this study. Patients used the ReWalk a median of 9 out of 16 days (primarily for exercise) taking a median of 3,226 steps. Overall, the exoskeleton was useful for exercise and social interaction but less useful for assistance with activities of daily living. The mean satisfaction score was 3.7 on a scale of 1 to 5 indicating satisfaction with the device.

Table 8. Summary of Key Case Series Characteristics

Study	Country	Participants	Treatment	Follow-Up
van Dijsseldonk et al. (2020)46	The Netherlands	Adults at least 6 months post motor-complete SCI between T1 and L1 (N = 14)	ReWalk Personal 6.0 for in-home use after 8 weeks of training	2 to 3 weeks of in-home use

L: lumbar; SCI: spinal cord injury; T: thoracic.

Section Summary: Powered Exoskeleton for Ambulation
Several small studies have evaluated the use of powered exoskeletons for ambulation in individuals with spinal cord injury in the institutional setting. These studies were included in a recently published systematic review that summarized the effects of the powered exoskeleton on walking, quality of life, and other secondary health conditions; however, the heterogeneity of outcome measures hindered authors from making general conclusions. One RCT, a randomized cross-over study, and a case series have assessed the use of powered exoskeletons in the home/community setting. Although these studies indicate that powered exoskeletons may be used safely in the outpatient setting, further research is necessary to assess efficacy and safety of the technology. High-quality, comparative studies are needed to determine the benefits of powered exoskeletons for ambulation both in institutional and community settings.

The purpose of the following information is to provide reference material. Inclusion does not imply endorsement or alignment with the evidence review conclusions.

Practice Guidelines and Position Statements
Guidelines or position statements will be considered for inclusion in Supplemental Information if they were issued by, or jointly by, a U.S. professional society, an international society with U.S. representation, or National Institute for Health and Care Excellence (NICE). Priority will be given to guidelines that are informed by a systematic review, include strength of evidence ratings, and include a description of management of conflict of interest.

American Physical Therapy Association
The American Physical Therapy Association published guidelines in 2020 providing recommendations to guide improvement of locomotor function after brain injury, stroke, or incomplete spinal cord injury in ambulatory patients.⁴⁷ The guidelines recommend against the use of powered exoskeletons for use on a treadmill or elliptical to improve walking speed or distance following acute-onset central nervous system injury in patients more than 6 months post-injury due to minimal benefit and increased costs and time.

A 2022 article by Hohl et al. comments on how this guideline recommendation adds uncertainty to the clinical application of powered exoskeletons in rehabilitation.⁴⁸ Several studies referenced in the guideline did not use the Food and Drug Administration (FDA)-approved devices discussed in this review; rather, the guideline focused on treadmill-based robots, specifically the Lokomat^®. Therefore, the conclusions should be interpreted with caution, given the substantial differences in functionality and physical demand between the treadmill-based robots and the powered exoskeletons of interest. Taking into consideration the limited guidance on proper use of powered exoskeletons, Hohl et al. developed a framework for clinical utilization of powered exoskeletons in rehabilitation settings. The aims of the framework are to: 1) assist practitioners with clinical decision making of when exoskeleton use is clinically indicated, 2) help identify which device is most appropriate based on patient deficits and device characteristics, 3) provide guidance on dosage parameters within a plan of care, and 4) provide guidance for reflection following utilization. The framework focuses specifically on clinical application, not use of powered exoskeletons for personal mobility.

U.S. Preventive Services Task Force Recommendations
Not applicable

Ongoing and Unpublished Clinical Trials
Some currently ongoing and unpublished trials that might influence this review are listed in Table 9.

Table 9. Summary of Key Trials

NCT No.	Trial Name	Planned Enrollment	Completion Date
Ongoing
NCT05187650	Effectiveness of a Powered Exoskeleton Combined With Functional Electric Stimulation for Patients With Chronic Spinal Cord Injury: a Randomized Controlled Trial	34	Dec 2025
NCT01701388	Investigational Study of the Ekso Powered Exoskeleton for Ambulation in Individuals With Spinal Cord Injury (or Similar Neurological Weakness)	40	Dec 2023 (active, not recruiting )
NCT04221373	Exoskeletal-Assisted Walking in SCI Acute Inpatient Rehabilitation	40	Jul 2022 (recruiting)
NCT04786821	Feasibility Study for a Randomised Control Trial for the Acceptability of Exoskeleton Assisted Walking Compared to Standard Exercise Training for Persons With Mobility Issues Due to Multiple Sclerosis	24	Sep 2022 (not yet recruiting)
Unpublished
NCT03082898	Mobility and Therapeutic Benefits Resulting From Exoskeleton Use in a Clinical Setting (SC140121 Study 1 and 2)	41 (actual enrollment)	Jun 2020 (completed)
NCT02658656	Exoskeleton Assisted-Walking in Persons with SCI (PEPSCI): Impact on Quality of Life	424 (actual enrollment)	Sep 2021 (completed)

NCT: national clinical trial; SCI: spinal cord injury.

References    

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12. Kubota S, Abe T, Kadone H, et al. Hybrid assistive limb (HAL) treatment for patients with severe thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL) in the postoperative acute/subacute phase: A clinical trial. J Spinal Cord Med. Jul 2019; 42(4): 517-525. PMID 30335588
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28. Birch N, Graham J, Priestley T, et al. Results of the first interim analysis of the RAPPER II trial in patients with spinal cord injury: ambulation and functional exercise programs in the REX powered walking aid. J Neuroeng Rehabil. Jun 19 2017; 14(1): 60. PMID 28629390
29. Karelis AD, Carvalho LP, Castillo MJ, et al. Effect on body composition and bone mineral density of walking with a robotic exoskeleton in adults with chronic spinal cord injury. J Rehabil Med. Jan 19 2017; 49(1): 84-87. PMID 27973679
30. Benson I, Hart K, Tussler D, et al. Lower-limb exoskeletons for individuals with chronic spinal cord injury: findings from a feasibility study. Clin Rehabil. Jan 2016; 30(1): 73-84. PMID 25761635
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Coding Section.

Codes	Number	Description
HCPCS	K1007	Bilateral hip, knee, ankle, foot device, powered, includes pelvic component, single or double upright(s), knee joints any type, with or without ankle joints any type, includes all components and accessories, motors, microprocessors, sensors (eff 10/01/2020) Prior to this date E1399 would have been used
	E0739 (effective 04/01/2024)	Rehab system with interactive interface providing active assistance in rehabilitation therapy, includes all components and accessories, motors, microprocessors, sensors
ICD-10-CM		Investigational for all relevant diagnoses
	G12.21	Amyotrophic lateral sclerosis
	G35	Multiple sclerosis
	G61.0	Guillain-Barre syndrome
	Q05.0-Q05.9	Spina bifida code range
	S34.101-S34.139	Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level code range
ICD-10-PCS		Not applicable. ICD-10-PCS codes are only used for inpatient services. There are no ICD procedure codes for devices.
Type of Service	DME
Place of Service	Outpatient

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive. 

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, and other nonaffiliated technology evaluation centers, reference to federal regulations, other plan medical policies and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

History From 2015 Forward     

04/15/2024	Added HCPCS code E0739 to coding section. No other changes made.
02/08/2024	Annual review, no change to policy intent. Updating regulatory status, rationale and references.)
02/15/2023	Annual review, no change to policy intent. Updating rationale.
02/10/2022	Annual review, no change to policy intent. Updating description, regulatory status, rationale, references and coding.
02/03/2021	Annual review, no change to policy intent. Updating references, regulatory status, guidelines and coding.
02/03/2020	Annual review, no change to policy intent. Updating background and rationale.
02/13/2019	Annual review, no change to policy intent. Updating background, rationale and references.
02/27/2018	Annual review, no change to policy intent. Updating background, description, regulatory status, rationale and references.
02/01/2017	Annual review, no change to policy intent. Updating background, description, rationale and references.
02/10/2016	Annual review, no change to policy intent.
02/09/2015	NEW POLICY