In a current first-in-human clinical trial, called STIMO (ClinicalTrials.gov, NCT02936453), Electrical Epidural Stimulation (EES) of the spinal cord is applied to enable individuals with chronic severe spinal cord injury (SCI) to complete intensive locomotor neurorehabilitation training. In this clinical feasibility study, EES immediately enhances walking function and, with repeated use as part of the EES-assisted neurorehabilitation program, improves leg motor control and neurological recovery in severe SCI participants to a certain extent. Linking brain activity to spinal stimulation, as shown in preclinical and clinical studies, enhances usability of EES and neurological recovery.
Clinatec (CEA, Grenoble, France) has developed an implantable electrocorticogram (ECoG) recording device with a 64-channel epidural electrode array called WIMAGINE capable of recording electrical signals from the motor cortex for an extended period and with a high signal to noise ratio. This ECoG-based system allowed tetraplegic patients to control an exoskeleton (Clinicaltrials.gov, NCT 02550522) with up to 8 degrees of freedom for the upper limb control. This device has been implanted in 5 chronic participants so far; one of them has been using this system both at the hospital and at home for more than 3 years.
The WIMAGINE ECoG technology has been integrated with epidural electrical stimulation (EES) across multiple clinical trials exploring implantable brain-spine interfaces. In the STIMO-BSI trial (NCT04632290), real-time decoding of cortical motor intentions for leg movements was used to modulate lumbar EES, enabling a chronic SCI participant to regain volitional control of standing and walking, with neurological improvements persisting even without the system after three years. In the UP2 trial (NCT05665998), two participants with incomplete C3/C4 SCI received cervical EES arrays and a WIMAGINE implant to decode up to six upper-limb motor states; brain-controlled cervical EES was shown to be safe, feasible, and supportive of neurological recovery of arm and hand function. In the Think2Go trial (NCT06243952), two participants with complete motor paraplegia received a WIMAGINE implant paired with the ARC-IM lumbar EES system, enabling lower-limb movement within days and leading to restored voluntary leg control and unsupported walking after months of rehabilitation. Together, these studies demonstrate that implantable ECoG-based brain-spine interfaces can safely decode motor intentions and drive targeted EES to restore multi-limb motor functions and promote neurological recovery across a range of SCI severities.
In this study, the investigators will assess the preliminary safety and effectiveness of ECoG-controlled EES in individuals with chronic stroke who suffer from hemiplegia, to establish a direct bridge between the motor intention and the spinal cord. This could improve or restore voluntary control of arm and leg movement as well as promote neurological recovery when combined with neurorehabilitation. The WIMAGINE ECoG system will be coupled with the ARC-IM purpose-built spinal cord stimulation technology in the ARC-BSI Stroke system, which is equivalent technology to systems currently used in the UP2 (ARC-BSI Cervical system) and Think2Go (ARC-BSI Lumbar system) clinical studies.
