Software Parameters Utilized During Overground Exoskeleton Gait Training Following Spinal Cord Injury

Research Objectives: Contemporary overground exoskeleton gait training (OEGT) devices are highly versatile, offering a plethora of software parameter options to individualize gait training sessions. To date, no clinical guidelines exist to guide OEGT parameter changes to promote functional recovery for patients with spinal cord injury (SCI). Thus, this retrospective analysis describes therapist-driven changes to software parameters across OEGT sessions for patients with SCI during inpatient rehabilitation.

Design: Retrospective analysis

Setting: Inpatient rehabilitation hospital

Participants: Eligible patients included those admitted with SCI to an inpatient rehabilitation hospital between July 2022 and October 2023, met exoskeleton manufacturer frame limitations, and completed ≥5 OEGT sessions during their length of stay.

Interventions: OEGT integrated into the physical therapy plan of care

Main Outcome Measures: Our primary outcome was the number of parameter changes across patient’s 1) first OEGT session, 2) midpoint OEGT session, and 3) final OEGT session. Specific parameters to modify device assistance (max, adapt, fixed, 2free) were extracted for each milestone session. Functional change in overground walking performance over the inpatient rehabilitation length of stay was measured by the Walking Index for Spinal Cord Injury (WISCI-II).

Results: 37 patients [median age=57 (42, 65) years; 81% male; 76% non-Hispanic, 68% Caucasian; 62% tetraplegic, ASIA Impairment Scale (AIS) A=8.1%, B=14%, C=22%, D=57%] completed 352 total sessions [median=8 (7,11)] with median number of steps per session=526 (398, 733), up time=20 minutes (15, 25), walk time=17 minutes (14, 22). Frequency of device parameter changes were observed to increase across OEGT sessions and differed by injury severity [First session mean= 0.43 changes (AIS A=1.00, B=0.00, C=0.75, D=0.33), [midpoint session =0.95 (AIS A=1, B=0.40, C=1.13, D=1.0), [final session= 0.95 [AIS A=1, B=0.6, C=0.88, D=1.05]. Regardless of injury severity, changes to software parameters lessened the amount of device assistance over time. Median WISCI-II scores improved from admission to discharge [AIS A=0.7 (1.2), 5.0 (4.6); B=0.4 (0.9), 3.4 (5.0); C=0.0 (0.0), 2.4 (4.2); D=1 (3.7), 7.2 (5.8)].

Conclusions: Although frequency of software parameter changes varied according to injury severity, changes progressively increased across sessions during inpatient rehabilitation to reduce overall assistance provided by the device , with the aim of increasing patient participation and effort. Correspondingly, improvement in functional outcomes was observed. Future efforts should seek to determine guidelines for parameter changes to enhance walking recovery following SCI.

Author(s) Disclosures: N/A