Involuntary contractions of the striated anal sphincters as a cause of constipation: report of a case.

Abstract

We present a case of anismus in a 36-year-old patient. He complained of therapy refractory constipation that had been present for 15 years, with delayed micturition and voiding by stages. During digital examination of the anal canal, we found spontaneous contractions of the sphincters at rest. The urethral pressure profile showed irregular contractions during micturition. The electromyogram, which was performed with concentric needle electrodes from the external anal sphincter, puborectalis, and external vesical sphincter, revealed synchronous contractions of these muscles. Injections of botulinum toxin into the sphincters showed good effects and no incontinence. Focal dystonia of the striated anal and vesical sphincters is a very rare cause of constipation but should be included in the differential diagnosis.