Decelerating burst and complex repetitive discharges in the striated muscle of the urethral sphincter, associated with urinary retention in women.

Abstract

SUMMARY A type of electromyographic activity, formerly referred to as "pseudomyotonia", can be recorded from the striated muscle of the urethral sphincter using a concentric needle electrode. There are two components to this activity, complex repetitive discharges and decelerating bursts. The latter usually dominate recordings and sound very like myotonic discharges. Analysis of these discharges indicates that they are a form of "bizarre repetitive discharge", and as such, result from ephaptic spread of excitation between muscle fibres rather than from excitation arising in the terminal branches of the motor axon. Profuse activity of this type has been found in 15 women with symptoms of urethral dysfunction, including 11 with urinary retention. It is suggested that this activity is associated with a failure of urethral sphincter relaxation.The striking EMG activity that may be recorded from the urethral sphincter with a needle electrode, was first reported as "pseudomyotonia" by DiBenedetto and Yalla in 1979.' Other reports of this activity in the urological literature have subsequently adopted the same terminology,24 with the exception-of Dyro et al,5 who used the term "complex repetitive discharges". Because such confusion surrounds the term "pseudomyotonia", we have avoided it and in a recent publication referred to the activity as " complex repetitive discharges" plus "decelerating burst" discharges.6 Although the term "complex repetitive discharges" introduced by Dyro et al' is very appropriate, it does not encompass the dominant component of such recordings, the bursts of activity which have a decelerating rate and therefore sound so like myotonic discharges. We discuss later the electromyographic terminology used to describe various abnormal discharges recorded from muscle.The significance of decelerating burst and complex repetitive discharge activity in the urethral sphincter has been obscure. It has been reported in adults and children with a wide range of urological

Central and peripheral motor conduction to cremasteric muscle

“…They were similar to the deceleration bursts and complex repetitive discharges described for the external urethral sphincter. 9 The complex repetitive discharges lasted longer than the so-called deceleration bursts and they had other features similar to those encountered in the extremity muscles in chronic neurogenic disorders ( Fig. 2A-C).…”

Non‐neurogenic urinary retention (Fowler's syndrome) in two sisters

“…In addition, they also ful¢lled the criteria for diagnosis of polycystic ovaries [POCS, 2004]; the ¢rst patient reported oligomenorhea, both had LH/FSH ratio well above two, and both had the appropriate ovarian abnormalities on ultrasonography [Pache et al, 1992]. The condition of obstructed voiding in women due to abnormal EMG activity in the US [Fowler et al, 1985], which is associated with polycystic ovaries [POCS, 2004], is now known as ''Fowler's syndrome'' [Fowler et al, 1988;Swinn et al, 2002].…”

“…However, in many such patients needle EMG of the urethral sphincter (US) muscle has demonstrated profuse abnormal spontaneous activity, called complex repetitive discharges and decelerating burst activity [Fowler et al, 1985;Fowler and Kirby, 1986]. Many of these women also had polycystic ovaries [Fowler et al, 1988], and this association was named Fowler's syndrome.…”

Patient Satisfaction and Complications Following Sacral Nerve Stimulation for Urinary Retention, Urge Incontinence and Perineal Pain: a Multicenter Evaluation

“…Surgery for stress incontinence is complicated by urgency and/or urge incontinence in up to 30%, and dysuria and/or retention in up to 5% of the patients, according to the type of surgery [18]. Dysuria and/or retention symptoms after surgery for stress incontinence may be due to partial denervation of the external sphincter [19]; these patients are also considered ideal candidates for sacral nerve stimulation [5±6].…”