Anismus has been recognized as a cause of chronic constipation. Failure of relaxation of the puborectalis muscle and the external anal sphincter muscle or a paradoxical contraction of both during straining to defecate is thought to be the cause of anismus or spastic pelvic floor syndrome and is associated with a difficult or impossible defecation. This pathology was documented by tests of anorectal physiology. The basic mechanism behind persistent constipation is the failure of the anorectal angle to straighten and of the anal canal to shorten as a result of sustained contraction of the puborectalis muscle [1].

Anismus is one of the many diseases that are easily underestimated, considering the patient's agony. Many colorectal specialists may have experiences with providing only reassurance to patients with anismus because they believe no definite, optimal treatment exists or suppose that the therapeutic result may not satisfy the patients. However, if colorectal specialists and clinicians understand more about anismus and try to evaluate it correctly, many more patients than we expect may receive more relief than we expect, even though that relief may only be mental relief.

According to the Rome classification [2], diagnosis of anismus is based on imaging "or" a physiologic study with the patient's symptoms. In this study [3], authors evaluate the discordances between imaging and physiologic studies, and the results should be practical and useful in clinical circumstances. Because diagnosis is not confirmed based on just one finding of those examinations, clinicians must understand how discordance can exist between the two. Consequently, because of that discordance, other morphological or functional conditions that mimic anismus or coexist with it must be found. However, the result of a physiologic study cannot be used to judge the result of an imaging study. If further study would be able to suggest a way to reduce the discordance between the two types of studies by combining the results of a balloon expulsion test, electromyography, and pudendal nerve terminal motor latency electromyography, which are also generally recommended to evaluate anismus [4], as developed from a description of the subjective discordance between the 2 studies, such a study would be of great interest.