Effect of robotic tilt table verticalization on recovery in patients with disorders of consciousness: a randomized controlled trial

Verticalization is a common therapeutic intervention during rehabilitation of patients with disorders of consciousness (DoC). The Erigo®Pro is a robotic tilt-table (RTT) with built-in stepping unit for the lower extremities to prevent orthostatic hypotension during verticalization. In addition, the system also provides functional electrical stimulation (FES) of muscles of the lower extremities. In this randomized controlled clinical trial (RCT), 47 patients with subacute DoC received a 4-week verticalization regime (16 verticalization sessions) and were allocated to one of three experimental groups: (1) verticalization by means of RTT with FES, (2) by means of RTT without FES, or (3) by conventional physiotherapy (CPT). Level of consciousness (LoC), spasticity, functional independence in daily activities, and functional brain connectivity measured by means of high-density quantitative EEG were assessed at baseline, directly after the verticalization program and after 6 months. There was a similar clinical improvement in all three experimental groups. RTT was not associated with an effect on any of the clinical outcomes. Verticalization or mobilization time during the study period was significantly positively correlated with recovery of consciousness (rho = 0.494, p < 0.001) in the short term and showed a statistical trend at the 6 months follow-up (rho = 0.244, p = 0.078). In conclusion, RTT treatment is not more effective in promoting recovery of consciousness than CPT in subacute DoC patients. Yet, our data suggest, that verticalization may be an important and feasible rehabilitation intervention in this group of patients. ClinicalTrials.gov NCT Number NCT02639481, registered on December 24, 2015.