Fig. 2

Spastic perineum syndrome. Mid sagittal TRUFI images at rest (a) reveal an obtuse ano-rectal angle which decreases during squeeze (b). During the strain phase, there is further reduction in ano-rectal angle with thick pubo-coccygeal muscle (white arrow) indenting the posterior rectal wall (c).In defecation phase, there is further reduction in ano-rectal angle with prominent indentation of posterior rectal wall by the thickened pubo-rectalis muscle (d)