Alterations in the H-reflex in the paraplegic induced by bladder distention.

This study has evaluated the changes in the characteristics of the H-reflex induced by distention of the urinary bladder in patients with complete lesions of the spinal cord. These findings were compared to induced changes in the systolic blood pressure and some degree of correlation was noted. It is well recognised that distention of the urinary bladder can exert a significant influence on the state of both somatic and autonomic reflex activity in spinal man. Although the mode of action of this stimulus has not been fully delineated, it is of some clinical importance since it may intensify muscular spasticity and autonomic hyperreflexia. This study was undertaken to further explore this relationship utilising the H-wave as a measure of segmental reflex activity. When appropriate, the effect of bladder distention on arterial blood pressure was also measured and an attempt made to correlate these observations with the H-wave findings.