Myo Flashcards
Describe the perineal body
Irregular fibromuscular mass in the midline between anal canal and perineal membrane
What is the irregular fibromuscular mass in midline between anal canal and perineal membrane?
perineal body
What does the perineal body contain, and what muscles is it an attachment point for?
Collagenous and elastic fibers
Bulbospongiosus m., external anal sphincter m., superficial transverse perineal m., deep transverse perineal m.
What is the attachment point for bulbospongiosus m., external anal sphincter m., superficial transverse perineal m., and deep transverse perineal m.?
Perineal body
What is sometimes classified as a central tendon of pelvic and urogenital diaphragms?
Perineal body
What are the origin and insertion sites for the superficial transverse perineal m.?
Origin: ischiopubic ramus and ischial tuberosity
Insertion: Perineal body
What originates on the ischiopubic ramus and ischial tuberosity and inserts on perineal body?
Superficial transverse perineal m.
What is the action of the superficial transverse perineal m?
Supports and fixes perineal body
Supports abdominopelvic viscera
Resists increases in intraabdominal pressure
What muscles supports/fixes perineal body, supports abdominopelvic viscera, and resists increases in intraabdominal pressure?
Superficial transverse perineal m.
Deep transverse perineal m (Male)
What innervates the superficial transverse perineal m?
Deep perineal nerve
What are the origin and insertion sites for ischiocavernosus m?
O: ischiopubic ramus and ischial tuberosity
I: Perineal membrane medial to Crura
Medial aspect of Crus of penis (male) or clitoris (female)
What muscle originates on ishciopubic ramus and ischial tuberosity and inserts on medial aspect of crus of penis/clitoris and perineal membrane medial to crura?
Ischiocavernosus m
What is the action of the ischiocavernosus m?
Maintain erection of penis or clitoris by compressing venous drainage, forcing blood from crura into body of penis or clitoris
What muscle maintains erection of penis/clitoris by compressing venous drainage, forcing blood from crura into body of penis/clitoris?
Ischiocavernosus m.
What innervates ischiocavernosus m?
Deep perineal n.
What are the origin and insertion sites for bulbospongiosus m.?
O: median raphe, ventral bulb of penis and perineal body (male), perineal body (female)
I: perineal membrane, fascia of bulb of penis and corpus spongiosum and corpora cavernossa of penis (male); fascia of bulb of vestibule of vagina, pubic arch and fascia of corpora cavernosa of clitoris (female)
What are the superficial perineal muscles?
Superficial transverse perineal m.
Ischiocavernosus m.
Bulbospongiosus m.
What muscle originates on the median raphe, ventral bulb of penis and perineal body (male), perineal body (female) and inserts on perineal membrane, fascia of bulb of penis and corpus spongiosum and corpora cavernosa of penis; fasia of bulb of vestibule of vagina, pubic arch and fascia of corpora cavernosa of clitoris?
Bulbospongiosus m
What is the action of the bulbospongiosus m.?
Support and fix perinal body
Compress bulb of penis, assist erection by compressing venous drainage, forcing blood form root of penis to body of penis, expels final drops of urine/semen from urethra
Compress vaginal orifice, assist in erection of bulbs of vestibule of vagina and compress greater vestibular gland
What muscle supports/fixes perineal body, compresses bulb of penis, assists erection by compressing venous drainage (forcing blood from root of penis to body of penis), expels final drops of urine/semen form urethra, compresses vaginal orifice, assists in erection of bulbs of vestibule of vagina, and compresses greater vestibular gland?
Bulbospongiosus m
What innervates the bulbospongiosus m?
Deep perineal n
Which superficial perineal muscle does not originate on ischiopubic ramus and ischial tuberosity?
Bulbospongiosus m
What does the deep perineal nerve innervate?
Superficial transverse perineal m
Ischiocavernosus m
Bulbospongiosus m
Deep transverse perineal m (male)
Describe the urogenital diaphragm
Muscle layer deep to and separated from superficial perineal muscles by perineal membrane.
However, may contain elements of superficial perineal muscles and perineal membrane
What muscle layer is deep to and separated from superficial perineal muscles by perineal membrane?
Urogenital diaphragm
What muscles make up urogenital diaphragm?
External urethral sphincter m
Deep transverse perineal m
External urethral sphincter m. And deep transverse perineal m. Make up what layer?
Urogenital diaphragm
What are the origin and insertion sites for external urethral sphincter m?
O/I: Surrounds urethra
What muscle surrounds the urethra?
External urethral sphincter m
What is the action of the external urethral sphincter m?
Constricts urethra, maintaining urinary continence
What muscles constricts the urethra, maintaining urinary continence?
External urethral sphincter m
Compressor urethrae m
What innervates the external urethral sphincter m?
Dorsal nerve of penis/clitoris
Where is the compressor urethrae m? O/I?
Extends laterally from external urethral sphincter
O: Ischiopubic ramus and ischial tuberosity
I: Median raphe and urethra via external urethral sphincter m.
What muscle originates from ischiopubic ramus and ischial tuberosity and inserts on median raphe and urethra via external urethral sphincter m?
Compressor urethrae m
What innervates the compressor urethrae m?
Dorsal nerve of penis/clitoris
What is the urethrovaginal sphincter m?
In female
Slips of external urethral sphincter m that also surround vagina
What muscle is slips of external urethral sphincter m that also surround vagina?
Urethrovaginal sphincter m
What are the origin and insertion sites of urethrovaginal sphincter m?
O: ischiopubic ramus and ischial tuberosity
I: external wall of vagina