Motor imagery has shown promising results to optimize tenodesis grasp in individuals with C6-C7 tetraplegia. However, efficacy of using motor imagery to improve grasping after tetraplegia requires further study with higher level of evidence. In addition, controlling covert practice remains difficult due to the absence of overt movements. However, similar brain activity measured during both over and cover movements makes possible to provide visual information about the covert practice performance using neurofeedback.

The Investigators thus designed this multicentric randomized controlled trial to investigate the effect of motor imagery with or with no visual neurofeedback on grasping capabilities after C6-C7 tetraplegia. They hypothesized that providing neurofeedback based on brain activity measured by electroencephalography namely knowing the covert practice performance would results in greater grasping improvement in response to practice as compared to motor imagery practice alone.

Inclusion Criteria:

• Volunteer individuals with C6-C7 tetraplegia with complete finger flexor paralysis restricting grasping capabilities to the tenodesis.
• Consent to participate to the study after receiving clear, loyal and appropriate information.
• Aged between 18 and 55 years.
• Time since spinal cord injury above 6 months
• Stabilized condition in particular sensori-motor deficit.
• Sitting position for more than 1 hour
• Able to imagine movement
• Health care beneficiary

Exclusion Criteria:

• Long-lasting autonomic disorders while sitting (orthostatic hypotension and/or blood pressure instability) limiting sitting position to less than 1 hour.
• Upper limb pain for either mechanic or neuropathic reasons preventing all grasping movement and/or the ability to imagine those movements.
• Restricted wrist and finger range of motion preventing the tenodesis grasp.
• Patient after surgical tendon transfer that improved grasping capabilities (e.g. active finger flexion).
• Ongoing participation in another research that aim to evaluate an intervention likely to improve the neurological or functional recovery introducing an experimental bias.
• Specific contraindication to Magnetoencephalography with the presence of metallic fragments inside the body such as pace-maker, neurostimulator, cochlear implants, steel dental implant and osteosynthesis material only applicable to the participants included in Lyon hospital center (n=15).

Individual participant data will be shared after deidentification (but only the data required for the new analysis will be transmitted). This includes for each visit and each participant averaged data of wrist extension angle during grasping of a single upper limb measured in degree with 3D motion analysis system.

This includes for each visit, each participant and each upper limb:

• Box and Block test
• Nine Hole Peg test
• hand held dynamometer for each of 4 muscles

This includes for each visit and each participant the total score of:

• manual muscle testing of the upper limb key muscles as defined by the ASIA score for each arm
• Capability of Upper Limb
• WHOQOL-Bref
• Quadriplegic Index of Function
• Kinesthetic Visual Imagery Questionnaire This also includes for each visit and each participant the passive range of motion expressed in degree and measured using goniometer for shoulder, elbow and wrist.

This do not include electrophysiological measurements.

Immediately following publication and ending 5 years following article publication.

Proposals should be directed to sebastien.mateo@chu-lyon.fr. To gain access, data requestors will need to sign a data access agreement.