Modification of spasticity by transcutaneous spinal cord stimulation in individuals with incomplete spinal cord injury. (March 2014)

• Record Type: Journal Article
• Authors: Hofstoetter, Ursula S.; McKay, William B.; Tansey, Keith E.; Mayr, Winfried; Kern, Helmut; Minassian, Karen
• Is Part Of: Journal of spinal cord medicine. Volume 37:Number 2(2014:Mar.)
• Page Start: 202
• Page End: 211
• Publication Date: 2014-03
• Subjects: Spinal cord -- Wounds and injuries -- Periodicals; Spinal cord -- Diseases -- Periodicals; 616.8305
• DOI: 10.1179/2045772313Y.0000000149
• Languages: English
• ISSNs: 1079-0268

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <sec> <title>Context/objective</title> <p>To examine the effects of transcutaneous spinal cord stimulation (tSCS) on lower-limb spasticity.</p> </sec> <sec> <title>Design</title> <p>Interventional pilot study to produce preliminary data.</p> </sec> <sec> <title>Setting</title> <p>Department of Physical Medicine and Rehabilitation, Wilhelminenspital, Vienna, Austria.</p> </sec> <sec> <title>Participants</title> <p>Three subjects with chronic motor-incomplete spinal cord injury (SCI) who could walk ≥10 m.</p> </sec> <sec> <title>Interventions</title> <p>Two interconnected stimulating skin electrodes (Ø 5 cm) were placed paraspinally at the T11/T12 vertebral levels, and two rectangular electrodes (8 × 13 cm) on the abdomen for the reference. Biphasic 2 ms-width pulses were delivered at 50 Hz for 30 minutes at intensities producing paraesthesias but no motor responses in the lower limbs.</p> </sec> <sec> <title>Outcome measures</title> <p>The Wartenberg pendulum test and neurological recordings of surface-electromyography (EMG) were used to assess effects on exaggerated reflex excitability. Non-functional co-activation during volitional movement was evaluated. The timed 10-m walk test provided measures of clinical function.</p> </sec> <sec> <title>Results</title> <p>The index of spasticity derived from the pendulum test changed from 0.8 ± 0.4 pre- to 0.9 ± 0.3 post-stimulation, with an improvement in the subject with the lowest pre-stimulation index. Exaggerated reflex responsiveness was decreased after tSCS across all subjects, with the most profound effect on passive lower-limb movement (pre- to post-tSCS EMG ratio: 0.2 ± 0.1), as was non-functional co-activation during voluntary movement. Gait speed values increased in two subjects by 39%.</p> </sec> <sec> <title>Conclusion</title> <p>These preliminary results suggest that tSCS, similar to epidurally delivered stimulation, may be used for spasticity control, without negatively impacting residual motor control in incomplete SCI. Further study in a larger population is warranted.</p> </sec> </abstract>