Axial Muscles- Muscles of the Pelvic Floor

Question 1

What are pelvic floor muscles?

Answer 1

• 3 layers of muscles and associated fasciae collectively form the floor of the pelvic cavity (known as the pelvic diaphragm)
• Extends from the ischium and pubis of the ossa coxae across the pelvic outlet to the sacrum and coccyx
• Support the pelvic viscera

Question 2

What is the coccygeus?

Answer 2

• Part of the deepest layer of the pelvic diaphragm (most superior)
• Pulls the coccyx anteriorly after its posterior deflation during defecation or childbirth

Question 3

What is the external anal sphincter?

Answer 3

• Located in the anal triangle region

- Assists in defecation

Question 4

What is the levator ani?

Answer 4

• Part of the deepest layer of the pelvic diaphragm (most superior)
• Largest and most important collection of muscles
• Supports the pelvic viscera and functions as a sphincter at the anorectal junction, uthera and vagina
• Formed by the iliococcygeus, pubococcygeus and puborectalis

Question 5

What is the puborectalis?

Answer 5

• Muscle forms a circular sling around the anorectal junction
• When contracted, it increases the bend or angle of the anorectal junction
• When an individual wishes to defecate, the puborectalis must be consciously relaxed to decrease the bend of the anorectal junction and allow for the easy passage of feces through rectum

Question 6

What is the perineum?

Answer 6

• The diamond shaped region between the lower appendages
• Has 4 significant bony landmarks: the pubic synthesis anteriorly, the coccyx posteriorly, and both ischial tuberosities laterally

Question 7

What is the urogenital triangle?

Answer 7

• Anterior section that contains the external genitalia and urethra
• Subdivided into a superficial and deep layer

Question 8

What is the anal triangle?

Answer 8

• Posterior section that contains the anus

Question 9

What is the superficial layer of the urogenital triangle?

Answer 9

• Composed of 3 muscles: bulbospongiosus, ischiocavernosus and superficial transverse perineal
• The ischiocavernosus attaches to the pubic symphysis, whereas the bulbospongiosus and superficial transverse perineal muscles attach to a tendinous central structure called the perineal body

Question 10

What is the deep layer of the urogenital triangle?

Answer 10

• Composed of 2 muscles: the deep transverse perineal and the external urethral sphincter