KAFO Orthoses Versus the ABLE Exoskeleton

This randomized crossover study will compare walking with KAFO type orthoses (current standard of care) versus the ABLE Exoskeleton device, during walking in patients with spinal cord injury in a hospital setting. The ABLE Exoskeleton is a robotic exoskeleton that actively assists individuals with mobility problems to stand up, walk and sit down.

The main objective of the study is to compare the energy efficiency during gait with both devices. Secondary objectives are: compare gait kinematics, usability, user's satisfaction, physical activity and psychosocial impact. The study will also serve to evaluate the usability and safety of the ABLE Exoskeleton in clinical practice.

Subjects will complete 10 gait training sessions during a 5-week period with 1 of the 2 devices randomly selected, followed by a post-training assessment consisting of 1 session. Once the test is completed, subjects will have a 2-week rest period after which they will repeat the process with the other device for 5 weeks (followed by 1 post-training assessment session). The study will be conducted at Hospital Asepeyo Barcelona in Spain, where a total of 10 patients will be recruited.

The primary objective of this study is determining the energy efficiency through gases exchange and kinematic gait analysis to compare the standard of assistance (KAFO type orthoses) and the ABLE Exoskeleton, a robotic gait assistance device, in patients with spinal cord injury (SCI) in a hospital setting.

The secondary objectives are to compare the performance of KAFO-type orthoses with that of the ABLE Exoskeleton device by:

* Kinematic analysis of gait and spatiotemporal gait parameters.
* Evaluation of the time and effort required to learn to use the device (usability).
* Evaluation of the impact that physical activity has on participants after gait training.
* Evaluation of the level of satisfaction of the participants.

In addition to these objectives, the safety of the ABLE Exoskeleton as an assistive device for gait rehabilitation in SCI patients will be evaluated throughout the study.

Participants will perform 2 training sessions per week of approximately 90 minutes duration for 5 weeks with each of the devices, completing a total of 10 sessions with KAFO type orthoses and 10 sessions with the ABLE Exoskeleton. Before starting the training period, the physical capacity of the participants will be measured. During the training period sessions, different measurements of the level of assistance, spatiotemporal gait variables and usability will be taken. Standardized clinical assessments will also be performed during sessions 5 and 10 (assessment sessions). At the end of the training period, a post-training assessment will be performed, consisting of 1 session where the physical capacity of the participants will be measured. After finishing the training period with one of the devices, participants will have a rest period of 2 weeks, after which they will change devices and repeat the whole process.

The main hypothesis of the study is that gait efficiency in patients with SCI is improved (lower energy consumption) when using the ABLE Exoskeleton device in comparison with KAFO-type orthoses. The increase in gait efficiency encourages patients to stand and walk for longer periods instead of using the wheelchair, which boosts their rehabilitation and improves their health.

Secondary hypotheses are:

* The ABLE Exoskeleton device will improve the kinematics and spatiotemporal parameters of gait (more closely resemble the gait pattern of a healthy individual), relative to KAFO-type orthoses.
* The ABLE Exoskeleton device will have a more positive impact on the mobility and psychosocial health of participants with SCI in the study, with respect to KAFO-type orthoses.
* The ABLE Exoskeleton device is a safe device to use in a hospital setting as an assistive device during gait rehabilitation in SCI patients.

Eligibility Criteria:
Inclusion Criteria:

* From 18 to 70 years old
* Chronic or subacute spinal cord injury.
* Currently in treatment as in-patient or ambulatory in the investigational site.
* From AIS A to AIS D with enough arm strength to withstand the bodyweight in a walking frame.
* Previous experience walking with KAFO orthoses (must tolerate standing).
* Ability to give informed consent

Exclusion Criteria:

* WISCI II \>16 without the exoskeleton.
* 5 or more fragility fracture risk factors according to Craven et al.
* History of fragility fractures of lower limbs in the past 2 years.
* Deterioration \> 3 points of the total International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) motor score within the last 4 weeks.
* Spinal instability
* Modified Ashworth scale (MAS) \> 3 in lower limbs
* Unable to tolerate 30 minutes standing without clinical symptoms of orthostatic hypotension.
* Unable to walk 5 meters with KAFO orthoses and the support of a walking frame with wheels.
* Psychological or cognitive issues that do not allow a participant to follow the study procedures.
* Any neurological condition other than SCI
* Medically unstable
* Severe comorbidities including any condition that a physician considers to not be appropriate to complete participation in the study.
* Ongoing skin issues
* Height, width, weight or other anatomical constraints (such as leg length differences) incompatible with the device
* Insufficient Range of Motion (ROM) for ABLE Exoskeleton device
* Known pregnancy or breastfeeding