Electromyographic study of the anal sphincter in women.

The objectives of this study were to identify the electromyographic (EMG) changes in the anal sphincters, and to determine whether there are myogenic or neurogenic damages to the muscles in stress incontinence in women (SI). Possible damage was expected while the number of EMG studies has reported evidence of denervation as a result of certain aethiologic factors. The intention was to determine risk factors for development of fecal incontinence. 110 women with SI and 91 women with spinal lesion (SL) were examined. The anal sphincters were examined in both groups by means of standarized EMG technique with concentric needle electrode. The results demonstrated predominatly neurogenic lesion of the anal sphincters in SL women and predominatly normal findings in SI women. The contribution of genitourinary or pelvic surgeries to the fecal incontinence in SI group has been established by means of discriminatory analysis.