Authors:
Cortes M; Thickbroom GW; Elder J; Rykman A; Valls-Sole J; Pascual-Leone A; Edwards DJ. Institution Cortes, M. Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Medical Research Institute, White Plains, NY, USA. Cortes, M. Department of Neurology, Cornell University, New York, NY, USA. Cortes, M. EMG and Motor Control Unit, Neurology Department, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain. Thickbroom, G W. Non-invasive Brain Stimulation and Human Motor Co ntrol Laboratory, Burke Medical Research Institute, White Plains, NY, USA. Thickbroom, G W. Department of Rehabilitation Medicine, Cornell University, New York, NY, USA. Elder, J. Department of Epidemiology, Cornell University, New York, NY, USA. Rykman, A. Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Medical Research Institute, White Plains, NY, USA. Valls-Sole, J. EMG and Motor Control Unit, Neurology Department, H ospital Clinic, Universitat de Barcelona, Barcelona, Spain. Pascual-Leone, A. Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. Pascual-Leone, A. Institut Universitari de Neurorehabilitacio Guttmann, Department of Neurology, Universitat Autonoma, Barcelona, Spain. Edwards, D J. Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Medical Research Institute, White Plains, NY, USA. Edwards, D J. Department of Neurology, Cornell University, New York, NY, USA. Edwards, D J. Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Title:
The corticomotor projection to liminally-contractable forearm muscles inchronic spinal cord injury: a transcranial magnetic stimulation study.
Source:
Spinal Cord. 55(4):362-366, 2017 Apr.
Abstract STUDY DESIGN:
A cross-sectional study in chronic spinal cord injury with cervical lesions (cSCI).
OBJECTIVE:
To determine the corticomotor projection and motor co rtex organization of paralyzed forearm muscles that presented only liminal voluntary activation.
SETTING:
Burke Medical Research Institute, White Plains, NY, USA. METHODS: We identified ten people with chronic SCI who had a wrist flexor or extensor muscle with a motor power (MP) of 1 over 5. We recorded motor evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) over the primary motor cortex of the hemisphere contralateral to the target muscle. We measured resting motor threshold (RMT), corticomotor latency (LTY), MEP amplitude (AMP) and performed cortical motor mapping to determine the optimal site (OPT) and map area (AREA). Results were compared with the data from 18 controls.
RESULTS:
A MEP in the target muscle was observed for all cSCI cases. LTY was normal, while corticomotor excitability (as determined by RMT and AMP ) was reduced in about half of the group. The OPT site of the motor map s was within control range for all cSCI cases, while AREA was reduced in three cases.
CONCLUSIONS:
Corticomotor conduction and cortical topography were appreciably normal despite only liminal activation of the target musc le with voluntary effort. Muscles with these characteristics may benefit from a targeted rehabilitation program even in the chronic phase after SCI.
Publication Type:
Journal Article.
