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Cervical multisegmental motor responses in healthy subjects
1Texas Woman's University, School of Physical Therapy, Houston, TX 77030, USA. msabbahi@twu.edu
Spinal Cord
|January 18, 2012
Summary
Electrical stimulation of the C7 cervical vertebrae evoked multisegmental motor responses in upper extremity muscles. These findings suggest a potential diagnostic tool for cervical spinal disorders.
Area of Science:
- Neuroscience
- Motor Control
- Clinical Electrophysiology
Background:
- The study investigates the physiological responses to electrical stimulation of the cervical spine.
- Understanding these responses is crucial for diagnosing neurological conditions affecting motor pathways.
Purpose of the Study:
- To describe multisegmental motor responses in the upper extremities following electrical stimulation of the C7 cervical spinal segment.
- To evaluate the potential diagnostic utility of these responses in patients with cervical spinal disorders.
Main Methods:
- This descriptive study involved stimulating the C7 spinal segment in healthy subjects using surface electrodes.
- Electromyographic (EMG) responses were recorded from various upper extremity muscles (abductor digiti minimi, abductor pollicis brevis, flexor carpi radialis, biceps brachii).
- Signal amplitude and deflection latency were measured, and descriptive statistics were applied.
Main Results:
- Stimulation elicited robust motor responses in all recorded upper extremity muscles, with the largest amplitudes observed in the abductor pollicis brevis and abductor digiti minimi.
- Bilateral muscular responses were recorded simultaneously, indicating widespread neural activation.
- Response latencies varied, with shorter latencies in the flexor carpi radialis and biceps brachii compared to the abductor digiti minimi and abductor pollicis brevis. No responses were observed in lower extremity muscles.
Conclusions:
- The observed responses are likely due to the stimulation of dorsal roots or motor nuclei in the cervical region.
- This electrophysiological technique shows promise as a method for assessing patients with cervical spinal disorders.
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