Clinical Investigation on Feasibility and Usability of the ABLE Exoskeleton Device for Individuals With Spinal Cord Injury to Perform Skills for Home and Community Environments

The loss of the ability to walk and the associated restriction of mobility presents a major challenge to people with spinal cord injury in an everyday environment designed for pedestrians. Exoskeletal technology has the potential to help people with impaired leg function to regain ambulation and thus improve their independence. This technology is not completely new, but due to their high access price (\~120k€/unit), high size and weight (\~25 kg), and need for trained physiotherapist supervision, commercially available exoskeletons are only found in large hospitals and only in very few cases get into patients' homes.

The company ABLE Human Motion S.L. (Barcelona, Spain) has developed a novel exoskeleton to overcome these disadvantages, which is more compact, lighter and easier to use.

The primary objective of this study is to determine the feasibility and usability of the ABLE Exoskeleton for persons with SCI to perform skills in home and community environments.

The primary objective of this study is to determine the feasibility and usability of the ABLE Exoskeleton for persons with SCI to perform skills for home and community environments during a training programme of up to 8 weeks. Results will be used to assess the potential of the device to be used in a home and community setting by persons with SCI, while providing meaningful insights to develop future features to improve its performance in those environments.

The secondary objectives are as follows:

* Assess the impact of ABLE Exoskeleton training on gait and function.
* Assess the effect of the ABLE Exoskeleton on the patients' perceived rate of exertion.
* Assess the impact of the ABLE Exoskeleton on the quality of life and general health of the participants.
* Assess the level of user satisfaction from participants and therapists of the ABLE Exoskeleton.
* Assess the psychosocial impact of the ABLE Exoskeleton for participants.

The primary hypothesis of this study is that the ABLE Exoskeleton is feasible to be used by persons with SCI to perform skills for home and community environments.

The secondary hypothesis is that the device will have a positive impact on the perceived rate of exertion, mobility and psychosocial health, and quality of life and general health of the study participants with SCI.

This is a multicenter pre-post quasi-experimental study. The pre-post period will cover 22 exoskeleton sessions (18 training sessions and 4 assessment sessions) over a period of up to 8 weeks. The study will have two centres specialized in SCI involved, one at Heidelberg University, Germany and another at Institut Guttmann, Spain. In total 10 patients will be recruited.

After obtaining a Patient Information Sheet and Informed Consent Form (PIS/ICF), patients will be screened. Patients who match inclusion and exclusion criteria and pass pre-study screening, will be enrolled into the study. First, there will be a familiarisation session (session 0), where participants will learn how to use the device. Participants will then undergo a training programme with the ABLE Exoskeleton three to five times a week for up to 8 weeks for a total of 18 training sessions and 4 assessment sessions. The assessment sessions with the device will be performed at 4 time-points throughout training: Baseline (Session 1), Mid-training (Session 11), Final-training (Session 21) and Home-Skills-Test (Session 22). This therefore means there will be a total of 22 exoskeleton sessions, including training and assessments. During each training session, feasibility measurements will be taken via the evaluation of the performance of exoskeleton skills. Four weeks after the post-training assessment, a follow-up assessment will be conducted with participants. At the end of the study, the participating therapists will be asked to fill out a satisfaction questionnaire.

Eligibility Criteria:
Participants will be taken from former or current patients at one of the two SCI centres.

Inclusion Criteria:

* 18 to 70 years of age
* Traumatic and non-traumatic SCI
* Motor incomplete SCI with Neurological Level of Injury (NLI) C5-L5, or, Motor Complete SCI with NLI T1-L5
* Time since onset of SCI \> 6 months
* Ability to give informed consent

Exclusion Criteria:

* WISCI II without exoskeleton of \>13
* 5 or more risk factors present for fragility as stated by Craven et al (Craven et al., 2009a).
* History of lower limb fragility fractures in the last 2 years
* Deterioration \> 3 points of the total ISNCSCI motor score within the last 4 weeks
* Spinal instability
* Modified Ashworth scale 4 in lower limbs
* Unable to tolerate 30 min standing without clinical symptoms of orthostatic hypotension
* Unable to perform a sit-to-stand transfer or stand in the device with assistance
* Psychological or cognitive issues that do not allow the participant to follow the study procedures
* Known pregnancy or breastfeeding
* Any neurological condition other than SCI
* Medically unstable - Unstable cardiovascular system, hemodynamic instability, untreated hypertension (Systolic blood pressure \> 140, Diastolic blood pressure \> 90 mmHg), unresolved DVT, uncontrolled autonomic dysreflexia.
* Severe comorbidities - Any condition that a physician considers to not be appropriate to complete participation in the study.
* Ongoing skin issues - Grade I or higher on EPUAP on areas that will be in contact with exoskeleton (European Pressure Ulcer Advisory Panel, 2019)
* Height, width, weight or other anatomical constraints (such as leg length differences) incompatible with the device
* Range of motion (ROM) restrictions in lower extremities, that are incompatible with the device