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Formed by a fibromuscular tube, with intrinsic and extrinsic qualities composed by amooth and striated muscular fibres that form the sphincterian complex having about to 3 to 4 cm in length1,7.
Huisman et al8 identify the vascular plexus of the submucosa of the proximal and distal urethra that contributes the tonus of the urethra, maintaining urethral coaptation, preventing urinary loss. The external sphincter or striated is of voluntary control, composed of striated musculature. These 2 sphincterian components are different, but act in a combined way7.