Anismus in patients with normal and slow transit constipation.

Area of Science:

• Gastroenterology
• Colorectal Surgery
• Physiology

Background:

• Intractable constipation presents with variable whole gut transit times.
• Anismus, or pelvic floor dysfunction, has been hypothesized as a cause for slow transit.
• Understanding anorectal function is key to differentiating constipation subtypes.

Purpose of the Study:

• To investigate differences in anorectal function, specifically anismus, in patients with slow versus normal whole gut transit times.
• To determine if anorectal dysfunction contributes to slow transit constipation.
• To clarify the role of electromyography in diagnosing functional anismus.

Main Methods:

• Studied 24 patients with intractable constipation (13 slow transit, 11 normal transit).
• Utilized videoproctography with synchronous sphincteric electromyography and anorectal manometry.
• Assessed pelvic floor contraction during defecation and rectal evacuation capacity.

Main Results:

• No significant differences in anorectal function were observed between slow and normal transit groups.
• Electromyographic evidence of anismus did not correlate with rectal evacuation ability or obstructed defecation symptoms.
• Videoproctography did not reveal differences in rectal evacuation between the groups.

Conclusions:

• Slow transit constipation is likely a primary disorder of colonic motility, not secondary to anorectal functional abnormalities.
• Electromyography findings of anismus alone are insufficient for diagnosis; they must be correlated with proctographic evidence of incomplete rectal evacuation.
• Functional anismus requires confirmation through objective measures of rectal emptying, not solely based on electromyography.