Anorectal and pelvic floor anatomy

Area of Science:

• Anatomy
• Pelvic Floor Disorders
• Continence

Background:

• The anorectum and pelvic floor are essential for continence, defecation, and pelvic organ support.
• In females, the pelvic floor also serves as part of the birth canal.
• These structures possess intricate interconnections via fascia, ligaments, and connections to the bony pelvis.

Purpose of the Study:

• To detail the anatomical structures of the anorectum and pelvic floor.
• To elucidate the components of the anal sphincter and pelvic diaphragm.
• To highlight the supportive role of various fascial and fibro-elastic elements.

Main Methods:

• Anatomical description based on existing literature.
• Detailed explanation of the multilayered anal sphincter.
• Enumeration of the four principal layers of the pelvic floor.

Main Results:

• The anal sphincter comprises inner smooth muscle and outer striated muscle (external sphincter and puborectalis).
• The pelvic floor includes endopelvic fascia, muscular pelvic diaphragm, perineal membrane, and superficial transverse perineii.
• The anorectum and pelvic floor are interconnected by various fascial and ligamentous structures, supported by the perineal body and fibro-elastic network.

Conclusions:

• The anorectum and pelvic floor are complex, interconnected structures critical for pelvic function.
• Detailed anatomical knowledge is fundamental for understanding and treating related disorders.
• The integrated network of muscles, fascia, and ligaments provides robust pelvic support.