Defining The Pelvic Region Flashcards
Bones that make the pelvis
Innominate bones (ilium, pubis, ischium) Sacrum Coccyx Ischial spine Ischial tuberosity
Innominate bones
Ilium
Ischium
Pubis
Ligaments of the pelvis [4]
Sacroiliac
Sacrococcygeal
Sacrospinous
Sacrotuberous
Ligaments of the pelvis
-Sacroiliac
Between sacrum and ilium
-anterior and posterior components
Ligaments of the pelvis
-Sacrococcygeal
Between sacrum to coccyx
Ligaments of the pelvis
-Sacrospinous
Between ischial spine and sacrum/coccyx
Ligaments of the pelvis
-Sacrotuberous
sacrum to ischial tuberosity
Location of the perineum (in females)
Space located at the pelvic inlet and inferior to the pelvic diaphragm
Diamond-shaped surface extending from mons pubis to medial surface of the thighs and posteriorly to gluteal folds
What is enclosed within the deep perineal pouch?[4]
Pouch above perineal membrane, towards the pelvis
- Urethra
- Vagina (F)
- Glands: bulbourethral (M)
- Perineal muscles that act as sphincters: compressor urethra or urethrovaginal sphincter (F)
What is enclosed with the superficial perineal pouch? [4]
Pouch that contains muscles to anchor the external genitalia
- Urethra
- Vagina and penis roof
- Glands: Bartholin (F)
- Perineal muscles: bulbospongiosus, ischiocavernosus
Pelvic cavity
-borders
Borders Posterior- sacrum/coccyx Anterior- pubic symphysis Inferior- pelvic floor Superior- pelvic brim Lateral- obturator internus m
Pelvic cavity
-contents
Reproductive organs/tracts
Bladder
Rectum
Pelvic musculature
Lines the wall
- Piriformis
- obturator internus
Lines the floor
- coccygeus
- levator ani (iliococcygeal, pubococcygeal, puborectalis)
Piriformis muscle
- origin
- course
- insertion
- action
Muscle of the pelvic wall
Origin
-Anterior surface of the sacrum
Course
- Projects laterally into the greater sciatic foramen
- over the ischial spine
Insertion
greater trochanter of femur
Action
-Rotation of the leg
Obturator internus
- origin
- course
- insertion
- action
Muscle of the pelvic wall
Origin
-internal surface of the obturator membrane
Course
- Through the lesser sciatic foramen
- below the ischial spine
Insertion
-greater trochanter of femur
Action
-Rotation of the femur
Pubococcygeus
- Origin
- insertion
- Action
Muscle of the pelvic floor
Origin
Posterior of pubic bone
Insertion
-Lateral fibres of coccyx
Action
-Supports the viscera in pelvic cavity
Puborectalis
- Origin
- insertion
- Action
Muscle of pelvic floor
Origin
-Posterior pubic bone, slings around rectalis
Insertion
-Behind the rectum
Action
-foecal continence and defecation,
Coccygeal muscle
Muscle of pelvic floor
Origin
-Ischial spine
Insertion
-inferior end of the sacrum + coccyx
Iliococcygeus
- origin
- insertion
- action
Muscle of pelvic floor
Origin
-tendinous arch- this is a feature of this muscle
insertion
- to the annococcygeal body
Nerve root of sciatic nerve
L4-S3
Nerve root of inferior gluteal
L5-S2
Nerve root of superior gluteal nerve
L4-S1
Nerve roots of the pelvic splanchnic nerves
S2-4
Coccyx
Posterior bone of the pelvis
Formed of 4 fused coccygeal bones
Sacrum
Posterior aspect of pelvis
-formed by fusion of the 5 sacral bones fused together
Pelvic brim
Border seperating the true/lesser and false/greater pelvis
consists of right and Left linea terminalis
- arcuate
- pectineal line
Blood supply of the pelvis
Anterior division of the internal iliac (branches-uterine, vesical, internal pudendal)
Gonads supplied by gonadal branch from abdominal aorta
Venous drainage of the pelvis
Internal iliac (to common iliac veins) Gonadal to IVC [from right gonadal] or L renal vein
Somatic Innervation of the pelvis
Somatic plexuses (L4-Co)
- Lumbosacral (L4-S4)
- Coocygeal (S4-Co)
Function: Motor [to muscle] and sensory
- sciatic nerve
- sup/inf gluteal
- pudendal)
Nerve root of pudendal nerve
-function
S2, S3, S4
-innervates pelvic floor muscles
Visceral Innervation of Pelvic Regions
Visceral Plexuses
-parasympathetic- pelvic splanchnic nerves
Action: Erection
Sympathetic
- sacral sympathetic trunk [paraverterbral]
- sup & inf hypogastric plexuses [prevertebral]
- Action: Ejaculation
