The technology

The Ekso GT robotic powered exoskeleton is for use in people with weak or paralysed legs caused by stroke, spinal cord injury or other neurological conditions. It is placed over the legs to help with standing and walking (Miller 2016), using battery-powered motors to drive the legs. As the user shifts their weight, sensors are activated that initiate steps (Sale 2016). Functional gait training using powered exoskeletons helps people to relearn step patterns and weight shifts, with the ultimate aim of helping them regain as much of their natural gait as possible.

Ekso is made up of an exoskeleton frame for the legs, passive ankle joints, a foot plate and an electric motor. There is also a backpack that contains a computer, battery and a wired controller (Kozlowski 2015). The exoskeleton is attached to the body by a series of straps set at a specific distance to ensure stability according to the patient's weight (Nitschke 2013). Ekso incorporates proprietary SmartAssist software, which allows the physiotherapist to set the power for each leg independently to best suit the user. Ekso can be used for more than 1 user and can be adapted to individual patients' specific needs. Settings for each user can be saved for use at their next session.

A physiotherapist initially supports the user to help prevent falling (Kozlowski 2015). Ekso is fully weight-bearing, which can reduce the physical load on the physiotherapist who is supporting the user. Physiotherapist support becomes less necessary over time with use of Ekso, but one should always be present when the device is used. Ekso should be used with assistive devices, such as a walker or crutches, to ensure balance (Kressler 2014).

During a treatment session, patients walk for increasingly longer periods and progress from using a front-wheeled walker to crutches for stability (Kozlowski 2015). The parameters of gait, such as stride length and height, can be changed as the patient progresses within training sessions. However, when walking with Ekso it is difficult to overcome obstacles or compensate for uneven ground. Because of this, Ekso is specifically a therapy device for gait training and not a device for independent walking (Nitschke 2013).

Regaining a natural gait helps people to overcome the practical and social issues related to not being able to stand or walk. Moreover, regular walking may also lead to an improvement in secondary medical problems associated with a lack of weight-bearing activity, such as osteoporosis, cardiovascular disease, respiratory problems and pressure ulcers (Miller 2016).

The innovation

Several wearable exoskeletons are available (Kolakowsky-Hayner 2013). However, the SmartAssist software incorporated in Ekso is potentially novel in allowing physiotherapists to strategically target aspects of a patient's gait by providing different amounts of support to each leg.

Current NHS pathway

The NICE guideline on stroke rehabilitation in adults recommends a number of treatment options for people with muscle weakness following a stroke. This includes strength training and walking therapies with or without support. Strength training focuses on progressive strength building through a combination of body weight activity repetitions, weights and resistance exercises. Walking therapies, such as using treadmills, aim to increase mobility and walking endurance. Ankle-foot orthosis devices and functional electrical stimulation are options for people who have difficulty walking following a stroke because of poor swing phase foot clearance. These interventions are also used for people with muscle weakness because of other neurological conditions.

Wheelchairs, hip-knee-ankle-foot orthosis devices, reciprocating gait orthosis devices and powered exoskeletons are also options for people with muscle weakness or paralysis. Using hip-knee-ankle-foot orthosis and reciprocating gait orthosis devices is tiring and many patients stop using them over time (Miller 2016). Powered exoskeletons may allow safe walking at a sustainable intensity of physical activity, although it is still labour-intensive for the physiotherapist administering the device (Miller 2016, Nitschke 2013).

NICE is aware of the following CE‑marked devices that appear to fulfil a similar function to Ekso:

  • HAL (Hybrid Assistive Limb robot; Cyberdyne)

  • ReWalk (ReWalk Robotics)

  • Rex (Rex Bionics)

Population, setting and intended user

Ekso should be used in a rehabilitation setting for adults with weakness or paralysis in their legs because of stroke, spinal cord injury or other neurological condition, but who still have strength in their arms and can use assistive walking devices. It is not expected that Ekso would be used in the home or long term.

Usually, physiotherapists will be responsible for therapy sessions using Ekso, once they have completed a training programme. Initial training on the device takes 1 week and allows physiotherapists to learn its basic features and use it under the supervision of a physiotherapist who is already familiar with Ekso. Training progresses to using Ekso's advanced features and eventually the second physiotherapist is not needed.

Use of the device is restricted to adults who are between 5 feet 2 inches and 6 feet 2 inches tall and who weigh less than 100 kg (220 pounds).

Costs

Device costs

The manufacturer provides Ekso to the NHS in a package costing £98,000 (excluding VAT). This package includes the Ekso GT robotic exoskeleton with the SmartAssist software, training for up to 4 physiotherapists, a 2‑year warranty and all supporting equipment (1 walker, 2 crutches, 1 control unit, 1 seat cushion, 1 kit bag, 2 battery sets and 1 charger). There is also a 'try before you buy' option (including the Ekso GT robotic exoskeleton with SmartAssist software and training but not the supporting equipment) for £1,650 per month. This option can be used for 3 to 5 months. Use of the device during this period counts towards the full purchase of the device within 12 months of the first training session.

Ekso CARE is a technical support and maintenance package, which can also be purchased from the manufacturer for £19,000 (excluding VAT). This includes coverage for 4 years for service and repair costs, access to software and limited hardware updates, technical support by phone and access to usage statistics through an online interface. Ekso CARE is provided at no additional cost when the 'try before you buy' option is chosen.

One Ekso exoskeleton device, including rechargeable batteries, is expected to have a 4‑year lifespan if routine maintenance is done. This estimate is based on Ekso being used 6 to 8 times a day, with a mean use time of 1 hour. Routine maintenance can be done by physiotherapists who use the device and doesn't need any manufacturer input.

Ekso could be used an estimated 1,500 times each year, assuming that it is used 50 weeks per year, 5 times per week and 6 times per day. Assuming that users have 15 to 20 hourly sessions, the device cost per patient is between £245 and £327.

Each session using Ekso must be done under the supervision of a physiotherapist, and in many sessions 2 therapists will be needed particularly during the initial period of physiotherapist training. The average cost of a physiotherapy visit, as an outpatient appointment, is £46 (Department of Health 2015).

Costs of standard care

A number of options are available on the NHS for people for whom Ekso may be considered. These include wheelchairs, hip-knee-ankle-foot orthosis devices, reciprocating gait orthosis devices and other exoskeletons. The cost of a wheelchair is based on patient need (low, medium or high) with the average cost of equipment ranging from £241 to £1,320 (Department of Health 2015). Relevant prices for all other options could not be identified. Patients would also need to visit a physiotherapist outpatient clinic when using Ekso, but the frequency and length of these visits is not known.

Resource consequences

The manufacturer states that Ekso is currently used in 1 NHS trust.

If adopted further, it is not expected that Ekso would lead to any significant changes in infrastructure but it may require extra outpatient clinics and physiotherapy services.

The use of Ekso may help patient mobility and reduce pain, so it could reduce subsequent resource use and costs in NHS and social care settings. However, there is currently no evidence for this so the resource and cost consequences are currently uncertain.