Inhibition of the triceps surae stretch reflex by stimulation of the deep peroneal nerve in persons with spastic stroke.
OBJECTIVE
To reduce the triceps surae stretch reflex by electrical stimulation of the deep peroneal nerve.


METHODS
Intervention study.


METHODS
Research institution.


METHODS
Sample of convenience of 10 spastic stroke individuals.


METHODS
After the deep peroneal nerve was stimulated between 0.9 and 4 times tibialis anterior motor threshold, the triceps surae was stretched to elicit a reflex.


METHODS
The triceps surae stretch reflex was quantified by the amplitude of the reflex electromyography (EMG) in soleus and medial gastrocnemius muscles and mean ankle moment. Paired t test and the Wilcoxon signed rank test (p < .05) were used to evaluate the effect of conditioning stimulation.


RESULTS
The soleus stretch reflex EMG was reduced significantly (p < .001) by stimulating the deep peroneal nerve to 25%+/-6% (standard error) of the unconditioned value (relaxed triceps surae). The optimal interval between stimulation and stretch was 141+/-15 msec. The velocity threshold increased significantly (p = .006) from a median value of 8 degrees per second to 33 degrees per second and the area under the stretch velocity/stretch reflex relation decreased significantly (p < .001) (soleus EMG).


CONCLUSIONS
The stretch reflex of relaxed triceps surae in persons with spastic stroke can be extensively reduced by stimulating the deep peroneal nerve at several times motor threshold of the tibialis anterior.
Veltink
P H
PH
Institute for Biomedical Technology (BMTI) Faculty of Electrical Engineering, University of Twente, Enschede, The Netherlands.
Ladouceur
M
M
Sinkjaer
T
T
D000368:Aged; D004558:Electric Stimulation; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D010543:Peroneal Nerve; D012026:Reflex, Stretch; D000071939:Stroke Rehabilitation