Walking With Overground Robotic Exoskeleton Device to Increase Behavioral Responsiveness in Patients With Disorders of Consciousness (WALK DOC)

The Coma Recovery Scale-Revised (CRS-R) is a 23-item behavioral assessment used to evaluate consciousness in patients with brain injuries. It measures auditory, visual, motor, oromotor, and communication functions. The total score ranges from a minimum of 0 to a maximum of 23, with higher scores indicating a higher level of neurobehavioral function and conscious awareness. CRS-R scores help characterize a patient's level of consciousness, including coma, vegetative state/unresponsive wakefulness syndrome, or minimally conscious state.

The Disability Rating Scale (DRS) is an 8-item clinical tool used to track a patient's recovery from a moderate-to-severe traumatic brain injury (TBI) from the coma stage through to community living. Scores range from 0 (no disability) to 29 (extreme vegetative state)

The CARE (Continuity Assessment Record and Evaluation) tool is a standardized CMS assessment used to measure the medical, functional, cognitive, and social needs of Medicare post-acute care patients

The assessment evaluates four major domains:

• Medical Domain: Monitors changes in severity, active treatments, pain, and pressure ulcers.
• Functional Domain: Evaluates self-care and mobility prior to and during the illness (e.g., assessing mobility and daily living activities).
• Cognitive Domain: Assesses functional cognition, cognitive impairments, and factors affecting outcomes.
• Social/Environmental Factors: Reviews living situations, support systems, and discharge planning needs.

Cortical activity will be recorded continuously during the study sessions using a 24-channel mobile electroencephalography (EEG) system. Key positional changes will be marked in the EEG recording. EEG spectral power, including power within predefined brain wave frequency bands, will be evaluated before, during, and after positional changes. Changes in these measures will be used to evaluate cortical activity across study conditions. EEG frequency measures will be reported in hertz (Hz).

Event-related potentials (ERP) will be recorded before and immediately after each study session. N100 ERP responses will be assessed, reflecting auditory sensory processing. For each response, the timing of the brain response (peak latency) will be measured. ERP latency measures will be reported in milliseconds (ms).

Event-related potentials (ERP) will be recorded before and immediately after each study session. P300 ERP responses will be assessed, reflecting basic attention processing. For each response, the timing of the brain response (peak latency) will be measured. ERP latency measures will be reported in milliseconds (ms).

Event-related potentials (ERP) will be recorded before and immediately after each study session. N400 ERP responses will be assessed, reflecting cognitive processing. For each response, the timing of the brain response (peak latency) will be measured. ERP latency measures will be reported in milliseconds (ms).

Safety of the study will be measure via Rate of Adverse Events (AE). Reported exoskeleton-emergent AE will include: increase in pain behavior or agitation, disconcerting changes in cardiovascular function (e.g., sudden drop in blood pressure), skin irritation or orthopedic injuries caused by the robotic exoskeleton device, sudden changes in alertness (e.g., somnolence), autonomic storming, and seizure activity.

Heart Rate Reserve (HRR) will be recorded as a measure of cardiovascular tolerability during the intervention. A heart rate monitor will be used to record the amount of time spent in each heart rate zone during ORE sessions: very light (<30% HRR), light (30-39%), moderate (40-59%), vigorous (60-89%), and near maximal (>90%).

Session completion rate (SCR) will be used to assess the feasibility of completing the scheduled overground robotic exoskeleton sessions. Feasibility will be measured by the percentage of scheduled sessions that each participant completes. Based on prior clinical experience delivering exoskeleton sessions to patients with disorders of consciousness, successful session completion will be defined as completing at least 75% of the scheduled overground robotic exoskeleton sessions. For any missed session, the reason for the missed session and whether the session was rescheduled or made up will be documented. The time needed to complete any make-up sessions will also be recorded. These data will help determine whether the intervention schedule is practical and manageable for participants.