Unit 4- Abdominopelvic Muscles Flashcards
(26 cards)
What is the fiber direction, layer, and actions of the following muscle?
Rectus Abdominis
Fiber Direction- vertical segments
Layer- superficial
Actions- flexes vertebral column + compressed abdominal wall
What is the fiber direction, layer, and actions of the following muscle?
External Oblique
Fiber Direction- inferomedial (hands in pocket)
Layer- superficial
Actions- lateral flexion of vertebral column and bilateral flexion of vertebral column and compresses abdominal wall
What is the fiber direction, layer, and actions of the following muscle?
Internal Oblique
Fiber Direction- inferolateral (hands over heart)
Layer- middle
Action- lateral flexion of vertebral column and bilateral flexion of vertebral column and compresses abdominal wall
What is the fiber direction, layer, and actions of the following muscle?
Transversus Abdominis
Fiber Direction- transverse
Layer- deep
Actions- lateral flexion of vertebral column and bilateral flexion of vertebral column and compresses abdominal wall
What is the Tendinous Intersections and Linea Alba?
Tendinous Intersections- breaks Rectus Abdominis muscle into segments
Linea Alba- located between L&R Rectus Abdominis muscles and is the midline fusion of aponeuroses of all 3 anterolateral abdominal muscles
How does the aponeurosis of all 3 abdominal muscles contribute to the rectus sheath?
External Oblique- sends aponeurosis into anterior lamina
Internal Oblique- sends aponeurosis into both anterior and posterior laminae
Transversus- sends aponeurosis into posterior lamina
All blend in midline to form linea alba
What is the action of the Quadratus Lumborum muscle?
laterally flexes the vertebral column and extends vertebral column
What is the action of the Iliacus muscle?
flexes thigh
What is the action of Psoas Major muscle?
flexes thigh
What muscle is formed inferior to the inguinal ligament when 2 of the 3 posterior abdominal muscles merge?
Iliopsoas = Psoas Major + Iliacus
Describe the pelvic diaphragm including the general structure and the 2 name muscular components
Muscular “hammock” that supports pelvic organs made up of coccygeus and levator ani
Floor of pelvic cavity and has openings that allow passage of structures
What are the 3 specific components of the Levator Ani muscle?
Iliococcygeus
Pubococcygeus
Puborectalis
What is the action of the pubococcygeus muscle?
Form pelvic floor and support pelvic viscera
What is the action of the Iliococcygeus?
Forms pelvic floor and supports pelvic viscera
What is the action of puborectalis?
supports anorectal junction and must relax to defecate
What are the bony landmarks of the perineum?
Anterior= pubic symphysis
Posterior= coccyx
Laterally= right and left ischial tuberosities
What are the 2 sub-triangles of the perineum?
Urogenital triangle and Anal triangle
What muscle structures present in the urogenital triangle of a biological female?
clitoris, urethral orifice, and vaginal orifice
What muscle structures present in the urogenital triangle of a biological male?
base of penis and scrotum
What are the 3 muscles that present in the genital triangle, regardless of gender?
Bulbospongiosus, Ischiocavernosus, and Superficial Transverse Perineal
What are the muscle structures and muscles that form the Anal Triangle?
Anus and External Anal Sphincter
Superficial Transverse Perineal and Levator Ani
What is the action of the Bulbospongiosus in a male?
ejects urine or semen, compresses base of penis, and stiffens penis
What is the action of the bulbospongiosus in females?
Narrows vaginal opening and compresses and stiffens clitoris
What is the action of the ischiocavernosus in males?
assists in erection of penis
