Abstract
We examined soleus H-reflex recruitment in 30 controls and 33 patients with spinal cord lesions and spastic spinal paresis. H-reflex gain and threshold were determined from recruitment curves after normalisation of stimulus intensity as a multiple of the current for a threshold M-response. Reflex gain was expressed as the mean slope of the H-reflex recruitment curve up to the half-maximal response size. Up to this point the curve follows an almost linear trajectory and will mainly reflect Ia afferent stimulation. This slope had a large variability but was clearly correlated with the H/M ratio. The mean gain was equal in controls and patients. The relation between H- and M-thresholds was expressed as a ratio which had a lower mean value in the patients. Though both H- and M-thresholds may be influenced by peripheral factors, this lower ratio suggests an increase in spinal motoneuron excitability in patients.
Original language | English |
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Pages (from-to) | 202-208 |
Number of pages | 7 |
Journal | Electroencephalography and Clinical Neurophysiology/ Evoked Potentials |
Volume | 93 |
Issue number | 3 |
DOIs | |
Publication status | Published - Jun 1994 |
Externally published | Yes |
Keywords
- Reflex gain
- Reflex threshold
- Soleus H-reflex recruitments
- Spasticity