Sensory stimulation augments the effects of massed practice training in persons with tetraplegia.
OBJECTIVE
To compare functional changes and cortical neuroplasticity associated with hand and upper extremity use after massed (repetitive task-oriented practice) training, somatosensory stimulation, massed practice training combined with somatosensory stimulation, or no intervention, in persons with chronic incomplete tetraplegia.


METHODS
Participants were randomly assigned to 1 of 4 groups: massed practice training combined with somatosensory peripheral nerve stimulation (MP+SS), somatosensory peripheral nerve stimulation only (SS), massed practice training only (MP), and no intervention (control).


METHODS
University medical school setting.


METHODS
Twenty-four subjects with chronic incomplete tetraplegia.


METHODS
Intervention sessions were 2 hours per session, 5 days a week for 3 weeks. Massed practice training consisted of repetitive practice of functional tasks requiring skilled hand and upper-extremity use. Somatosensory stimulation consisted of median nerve stimulation with intensity set below motor threshold.


METHODS
Pre- and post-testing assessed changes in functional hand use (Jebsen-Taylor Hand Function Test), functional upper-extremity use (Wolf Motor Function Test), pinch grip strength (key pinch force), sensory function (monofilament testing), and changes in cortical excitation (motor evoked potential threshold).


RESULTS
The 3 groups showed significant improvements in hand function after training. The MP+SS and SS groups had significant improvements in upper-extremity function and pinch strength compared with the control group, but only the MP+SS group had a significant change in sensory scores compared with the control group. The MP+SS and MP groups had greater change in threshold measures of cortical excitability.


CONCLUSIONS
People with chronic incomplete tetraplegia obtain functional benefits from massed practice of task-oriented skills. Somatosensory stimulation appears to be a valuable adjunct to training programs designed to improve hand and upper-extremity function in these subjects.
Beekhuizen
Kristina S
KS
Department of Veterans Affairs Medical Center, Miami, FL, USA.
Field-Fote
Edelle C
EC
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D004599:Electric Stimulation Therapy / Q000379:methods*; D019054:Evoked Potentials, Motor; D005260:Female; D005500:Follow-Up Studies; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D015601:Injury Severity Score; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011336:Probability; D011782:Quadriplegia / Q000175:diagnosis / Q000534:rehabilitation*; D020127:Recovery of Function; D012016:Reference Values; D018570:Risk Assessment; D013003:Somatosensory Cortex / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000175:diagnosis / Q000534:rehabilitation*; D013997:Time Factors; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome; D034941:Upper Extremity