Paretic Upper Extremity Movement Gains Are Retained 3 Months After Training With an Electrical Stimulation Neuroprosthesis

Abstract

Persch AC, Page SJ, Murray C. Paretic upper extremity movement gains are retained 3 months after training with an electrical stimulation neuroprosthesis. ObjectiveTo determine retention of upper extremity (UE) motor changes 3 months after participation in a regimen in which subjects with moderate UE hemiparesis engaged in repetitive task-specific training using an electrical stimulation neuroprosthesis (ESN). DesignProspective, blinded, cohort, pre-post study. SettingOutpatient rehabilitation hospital. ParticipantsIndividuals (N=24) in the chronic stage of stroke exhibiting stable UE hemiparesis (11 men; mean age, 57.9±9.5y; age range, 39–75y; mean time since stroke at time of repetitive task-specific practice [RTP] using ESN intervention start, 36.7mo; range of onset, 7–162mo). InterventionAs part of a larger trial, subjects had been randomly assigned to receive an 8-week regimen comprised of RTP on valued activities using the ESN. This observational study assessed this single group's paretic UE motor levels immediately after, and 3 months after, the intervention. Main Outcome MeasuresThe Fugl-Meyer (FM) assessment of sensorimotor impairment, the Action Research Arm Test (ARAT), the Arm Motor Ability Test (AMAT), and the Box and Block Test (BBT). ResultsNone of the scores significantly changed from the period directly after intervention to the test 3-months follow-up (FM: t=1.64; ARAT: t=2.17; AMAT: t=.76, .92, and 1.01 for the functional ability, quality of movement, and time scales, respectively; BBT: t=.36; adjusted t critical value to reject the null [tcrit]=2.90, 2-tailed α=.008 to preserve experiment-wise error rate of .05). ConclusionsSubjects exhibited no changes in the various functional tests, indicating that changes in paretic UE movement realized through RTP using ESN appear to be retained 3 months after the intervention has concluded. This was the first study to our knowledge to examine the longer-term effects of RTP using an ESN in any population.