Abnormal electromyographic activity (decelerating burst and complex repetitive discharges) in the striated muscle of the urethral sphincter in 5 women with persisting urinary retention.

In five women with urinary retention, recordings from the striated muscle of the urethral sphincter revealed highly abnormal electromyographic (EMG) activity. Using a concentric needle electrode, recordings revealed very striking bursts of activity, referred to here as decelerating burst (DB) and complex repetitive discharges (CRD). Such EMG activity is exceedingly unusual in skeletal striated muscle and resembles most closely the rarely encountered condition of "pseudomyotonia". We suggest that this abnormal activity is associated with a failure of relaxation of the striated muscle of the urethral sphincter, which results in chronic retention.