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Pelvis and PerineumPelvis and Perineum

The bony pelvis and jointsThe bony pelvis and joints

IleumIleum IschiumIschium PubisPubis SacrumSacrum CoccyxCoccyx

Joints:Joints:

*Sacroiliac joint*Sacroiliac joint

*Sacrococcygeal jt.*Sacrococcygeal jt.

*Symphysis pubis*Symphysis pubis

Bony partsBony parts

The The pelvic inlet pelvic inlet or or pelvic brimpelvic brim: : a bony rim made up of the a bony rim made up of the sacral promontory, sacral promontory, the the iliopectineal line iliopectineal line and the and the superior border of the superior border of the svmphysis pubissvmphysis pubis. .

The pubic tubercle(s). The pubic tubercle(s). The The obturator foraminaobturator foramina. . The The pubic arch pubic arch (made up of a (made up of a

right and a left ramus). right and a left ramus). The The ischial tuberositiesischial tuberosities: verify : verify

on yourself that this is the part on yourself that this is the part you sit on. you sit on.

The The ischial spinesischial spines. . The The acetabulumacetabulum. A Unshaped . A Unshaped

socket which articulates with socket which articulates with the head of the femur the head of the femur

The Sacrum and coccyxThe Sacrum and coccyx

Promontory of the Promontory of the sacrumsacrum

Anterior sacral Anterior sacral ForaminaForamina

Posterior sacral Posterior sacral foraminaforamina

Sacral hiatusSacral hiatus Coccygeal boneCoccygeal bone

The The pelvic outletpelvic outlet: A diamond-shaped area, best appreciated when : A diamond-shaped area, best appreciated when viewed from below. The boundaries of the pelvic outlet are: viewed from below. The boundaries of the pelvic outlet are:

the the pubic symphysispubic symphysis, right and left rami of the , right and left rami of the pubic archpubic arch, the , the ischial tuberositiesischial tuberosities, the , the sacrotuberous ligamentssacrotuberous ligaments and the tip and the tip

of the of the coccyxcoccyx. .

In the living person (or the intact cadaver) there are 2 In the living person (or the intact cadaver) there are 2 important ligaments which help to stabilize the bony important ligaments which help to stabilize the bony

pelvis: pelvis: The sacrospinous ligament and the sacrotuberous The sacrospinous ligament and the sacrotuberous

ligament.ligament.

DifferencesDifferencesCharacteristicCharacteristicss

Male pelvisMale pelvis Female pelvisFemale pelvis

SizeSize SmallerSmaller LargerLarger

Greater Greater sciatic notchsciatic notch

NarrowerNarrower WiderWider

Inferior pubic Inferior pubic angleangle

NarrowerNarrower WiderWider

False pelvisFalse pelvis TallTall FlaredFlared

Pelvic inletPelvic inlet AndroidAndroid Gynecoid Gynecoid

Pelvic outletPelvic outlet SmallerSmaller Larger Larger

. . Two muscles and their fasciae form Two muscles and their fasciae form

part of the walls of the pelvic cavity:part of the walls of the pelvic cavity: The The piriformis musclepiriformis muscle:: Takes origin from the front Takes origin from the front

of the sacrum near the 3rd and 4th sacral foramina. of the sacrum near the 3rd and 4th sacral foramina. The muscle leaves the pelvis by passing laterally The muscle leaves the pelvis by passing laterally through the greater sciatic foremen and inserts on through the greater sciatic foremen and inserts on the upper border of the greater trochanter of the the upper border of the greater trochanter of the femur. femur.

The The obturator internus muscleobturator internus muscle:: Takes origin Takes origin from the inner surface of the obturator membrane, from the inner surface of the obturator membrane, which closes over most of the obturator foremen, which closes over most of the obturator foremen, and from the interior surfaces of the pubis and and from the interior surfaces of the pubis and ischium, below the Iliopectineal line, and from the ischium, below the Iliopectineal line, and from the pubic ramus. This is a fan-shaped muscle which pubic ramus. This is a fan-shaped muscle which becomes tendinous as it passes through the lesser becomes tendinous as it passes through the lesser sciatic foremen. The tendon inserts on the greater sciatic foremen. The tendon inserts on the greater trochanter of the femur. trochanter of the femur.

The Piriformis and Obturator internus The Piriformis and Obturator internus musclesmuscles

Two muscles and their fasciae form the Two muscles and their fasciae form the floor of the pelvic cavity, the pelvic floor of the pelvic cavity, the pelvic

diaphragm: diaphragm: The The levator ani musclelevator ani muscle:: This is a thin sheet of muscle which This is a thin sheet of muscle which takes origin from the pubic bone and the adjacent fascia of the takes origin from the pubic bone and the adjacent fascia of the obturator internus muscle on the coccyx; onto a fibrous band obturator internus muscle on the coccyx; onto a fibrous band running from the rectum and coccyx called the running from the rectum and coccyx called the anococcygeal anococcygeal rapinerapine; and onto a fibrous body lying between the prostate or ; and onto a fibrous body lying between the prostate or vagina and rectum, known as the vagina and rectum, known as the perineal body.perineal body. The levator ani The levator ani muscle can be subdivided, depending on the exact origin and muscle can be subdivided, depending on the exact origin and insertion of the fibers: insertion of the fibers:

levator prostatae levator prostatae or sor sphincter vaginaephincter vaginae - include the fibers - include the fibers taking origin from the posterior surface of the pubis, and inserting in taking origin from the posterior surface of the pubis, and inserting in the perineal body. These form a "sling" around the prostate or the perineal body. These form a "sling" around the prostate or vagina. vagina.

puborectalis puborectalis - origin from the posterior surface of the pubis, and - origin from the posterior surface of the pubis, and form a sling around the rectum. The puborectalis is thought to be form a sling around the rectum. The puborectalis is thought to be important in maintaining fecal continence, important in maintaining fecal continence, rectal slingrectal sling

pubococcvgeuspubococcvgeus - origin from the posterior surface of the pubis and - origin from the posterior surface of the pubis and insert into the anococcygeal rapine. insert into the anococcygeal rapine.

iliococcvgeusiliococcvgeus - origin from the obturator internus fascia and - origin from the obturator internus fascia and ischium and insert into the anococcygeal rapine.ischium and insert into the anococcygeal rapine.

The The coccvgeus musclecoccvgeus muscle: takes origin from the ischial spine and : takes origin from the ischial spine and inserts onto the lower part of the sacrum and coccyx. inserts onto the lower part of the sacrum and coccyx.

Muscles forming the pelvic diaphragmMuscles forming the pelvic diaphragmLevator ani and Coccygeus muscleLevator ani and Coccygeus muscle

Orientation of the Abdominal and Orientation of the Abdominal and Pelvic cavitiesPelvic cavities

Arterial blood supply to the pelvisArterial blood supply to the pelvis

Venous and Lymphatic drainage Venous and Lymphatic drainage

Nerve supply of the pelvisNerve supply of the pelvis

Lumbosacral plexus – provides the somatic Lumbosacral plexus – provides the somatic innervation to the pelvis and lower innervation to the pelvis and lower

extremitiesextremities

1.1. Lumbosacral trunkLumbosacral trunk

-lies in the posterior abdominal wall and -lies in the posterior abdominal wall and iliac fossa.iliac fossa.

2. Sacral plexus – lies in the minor pelvis, 2. Sacral plexus – lies in the minor pelvis, supplies the gluteal,posterior thigh, leg,& supplies the gluteal,posterior thigh, leg,& footfoot

3. Pelvic splanchnic nerve from S2 to S43. Pelvic splanchnic nerve from S2 to S4

consists of parasympathetic, preganglionic consists of parasympathetic, preganglionic fibers and visceral afferent fibers.fibers and visceral afferent fibers.

Major branches of the Sacral Major branches of the Sacral PlexusPlexus

Superior gluteal nerve(L4-S1) to the gluteus medius and minimus. Superior gluteal nerve(L4-S1) to the gluteus medius and minimus. Injury “abductor lurch” a rolling gait due to loss of abductive Injury “abductor lurch” a rolling gait due to loss of abductive power of the hips.power of the hips.

Inferior gluteal(L5-S1) to the gluteus maximus. Injury results to Inferior gluteal(L5-S1) to the gluteus maximus. Injury results to difficulty in climbing stairs or rising from chair.difficulty in climbing stairs or rising from chair.

Common peroneal nerve(L4-S2) to the anterior leg and dorsum of Common peroneal nerve(L4-S2) to the anterior leg and dorsum of foot. Injury results to inability to dorsiflex ( foot drop) and evert foot. Injury results to inability to dorsiflex ( foot drop) and evert the foot.the foot.

Tibial nerve (L4-S3anterior) to the posterior of thigh, leg & plantar Tibial nerve (L4-S3anterior) to the posterior of thigh, leg & plantar of foot. Injury results to inability to stand on toes and loss of of foot. Injury results to inability to stand on toes and loss of Achilles tendon reflexAchilles tendon reflex

Pudendal nerve (S2-S4 anterior) lies in the Alcocks canal.Pudendal nerve (S2-S4 anterior) lies in the Alcocks canal. Inferior rectal nerve – motor to external anal sphincter and sensory Inferior rectal nerve – motor to external anal sphincter and sensory

toinferior part of anal canal and anal triangletoinferior part of anal canal and anal triangle Perineal nerve – motor to urogenital diaphragm and external genitalia, Perineal nerve – motor to urogenital diaphragm and external genitalia,

sensory to urogenital triangle of perineum and external genitaliasensory to urogenital triangle of perineum and external genitalia

There are 4 major "gateways" to There are 4 major "gateways" to

the lower limbthe lower limb Structures passing Structures passing under the inguinal ligamentunder the inguinal ligament

Iliopsoas muscle, Femoral nerve, Femoral artery Iliopsoas muscle, Femoral nerve, Femoral artery and veinsand veins

Lymphatic drainage to inguinal nodesLymphatic drainage to inguinal nodes Via Obturator foramen = Obturator nerve & vesselsVia Obturator foramen = Obturator nerve & vessels Via the Sciatic foramen = piriformis m., inferior Via the Sciatic foramen = piriformis m., inferior

gluteal nerves & vessels, superior gluteal nerves & gluteal nerves & vessels, superior gluteal nerves & vessels , sciatic nervevessels , sciatic nerve

Via Lesser sciatic foramen = obturator internus Via Lesser sciatic foramen = obturator internus tendontendon

Major organs in the pelvic cavity, The Major organs in the pelvic cavity, The Urinary systemUrinary system

Organs in the pelvic cavity, The RectumOrgans in the pelvic cavity, The Rectum

Organs in the pelvic cavity, The Organs in the pelvic cavity, The Reproductive organsReproductive organs

Development of the External Development of the External genitaliagenitalia

Indifferent stage week 3 – 6Indifferent stage week 3 – 6 Cloacal fold separates the lumen of the hindgut from the Cloacal fold separates the lumen of the hindgut from the

perineal regionperineal region Genital tubercle form from the fusion of the cloacal foldsGenital tubercle form from the fusion of the cloacal folds Urorectal septum divides the cloaca into urogenital sinus Urorectal septum divides the cloaca into urogenital sinus

and anal canaland anal canal The fusion of the urosinus with cloacal membrane forms The fusion of the urosinus with cloacal membrane forms

the central tendon of the perineum ( perineal body) and the central tendon of the perineum ( perineal body) and divides into urethral fold and anal fold.divides into urethral fold and anal fold.

Genital swellings (labial and scrotal fold)Genital swellings (labial and scrotal fold) Urogenital and anal membrane degenerate to form an Urogenital and anal membrane degenerate to form an

opening of the alimentary canal and urogenital canal to opening of the alimentary canal and urogenital canal to the perineum.the perineum.

Definitive external genitalia of Definitive external genitalia of malemale

Phallus = produced by the elongation of Phallus = produced by the elongation of the genital tubercle on the 12the genital tubercle on the 12thth week week

1313thth week, scrotal fold migrate posteriorly week, scrotal fold migrate posteriorly and fuse to form the scrotum. Testes lies and fuse to form the scrotum. Testes lies in the inguinal regionin the inguinal region

1616thth week the glans penis differentiates. week the glans penis differentiates. 77thth month testes starts to descend thru month testes starts to descend thru

the inguinal canal to the scrotumthe inguinal canal to the scrotum

Congenital anomalies of the Congenital anomalies of the penispenis

Hypospadias – incomplete dusion of Hypospadias – incomplete dusion of penile urethra opening in the ventral penile urethra opening in the ventral surface.surface.

Epispadias – opening of the urethra Epispadias – opening of the urethra in the dorsal surfacein the dorsal surface

Micropenis – congenital absence Micropenis – congenital absence Doubling of the glans penisDoubling of the glans penis

Definitive external genitalia for Definitive external genitalia for femalesfemales

Clitoris – formed by the slight elongation of the Clitoris – formed by the slight elongation of the genital tuberclegenital tubercle

Labia majora develop from the genital swellings.Labia majora develop from the genital swellings. Ovaries develop and migrate in the 9Ovaries develop and migrate in the 9thth week, week,

formation of the ovarian ligament and round formation of the ovarian ligament and round ligament of the ovaryligament of the ovary

1313thth week the Ovaries lie in the minor pelvis, forms week the Ovaries lie in the minor pelvis, forms the suspensory ligament of the ovary. the suspensory ligament of the ovary.

An evagination of the coelom (processus vaginalis, An evagination of the coelom (processus vaginalis, canal of Nuck) penetrates the abdominal wall of canal of Nuck) penetrates the abdominal wall of the inguinal region and enters the labial foldthe inguinal region and enters the labial fold

The Male and Female Reproductive organs The Male and Female Reproductive organs and its functionsand its functions

Important information about male Important information about male

pelvic reproductive system.pelvic reproductive system. The vas deferens pass behind the prostate gland. The vas deferens pass behind the prostate gland. The seminal vesicles also lie posterior to the bladder, lateral to The seminal vesicles also lie posterior to the bladder, lateral to

the vas deferens. the vas deferens. The ducts of the seminal vesicles join up with the ductus The ducts of the seminal vesicles join up with the ductus

deferens to form the ejaculatory ducts in the substance of the deferens to form the ejaculatory ducts in the substance of the prostate gland. prostate gland.

The ejaculatory ducts empty into the prostatic urethra, and from The ejaculatory ducts empty into the prostatic urethra, and from that point on spermatozoa travel through the urethra to get to that point on spermatozoa travel through the urethra to get to the outside (or inside) world. the outside (or inside) world.

Secretions of 3 pairs of glands, the, prostate and bulbourethral Secretions of 3 pairs of glands, the, prostate and bulbourethral glands are added to the substance that is ejaculated (semen). glands are added to the substance that is ejaculated (semen). Secretions of the seminal vesicles and prostate seem to play an Secretions of the seminal vesicles and prostate seem to play an important role in sperm motility. Secretions of the bulbourethral important role in sperm motility. Secretions of the bulbourethral glands appear to be more important for lubrication during glands appear to be more important for lubrication during sexual arousal. sexual arousal.   

Important features of the Female Important features of the Female reproductive organreproductive organ

Although the ovaries are completely surrounded by Although the ovaries are completely surrounded by peritoneum (they are intraperitoneal and have a short peritoneum (they are intraperitoneal and have a short mesentery, the mesovarium)mesentery, the mesovarium)

When the ovarian follicle ruptures, the ovum ruptures When the ovarian follicle ruptures, the ovum ruptures through the peritoneal covering into the through the peritoneal covering into the peritoneal cavity. peritoneal cavity.

The ovum is then picked up by the fimbriae at the The ovum is then picked up by the fimbriae at the expanded end of the uterine tube, called the infundibulum, expanded end of the uterine tube, called the infundibulum, which are highly motile.which are highly motile.

An ovum produced by the left ovary may be picked up by, An ovum produced by the left ovary may be picked up by, and migrate through either the right or left uterine tube. and migrate through either the right or left uterine tube.

The uterine tubes open into the peritoneal cavity. Therefore The uterine tubes open into the peritoneal cavity. Therefore in the female, the potential exists for infection to spread in the female, the potential exists for infection to spread from the uterine tubes to the peritoneal cavity. from the uterine tubes to the peritoneal cavity.

Muscle of the PerineumMuscle of the Perineum

Superficial transverse perineal, to central perineal Superficial transverse perineal, to central perineal body, stabilizes perineum S2.S4body, stabilizes perineum S2.S4

Deep transverse perineal, to midraphe & CPB, Deep transverse perineal, to midraphe & CPB, reinforce pelvic floor stabilizes vagina, S2-reinforce pelvic floor stabilizes vagina, S2-S4,Pud.n.S4,Pud.n.

External urethral sphincter, to circumurethral, External urethral sphincter, to circumurethral, urinary continence, S2,S4, Pud.n.urinary continence, S2,S4, Pud.n.

Ischiocavernosus, to body of penis or clitorisIschiocavernosus, to body of penis or clitoris Bulbocavernosus, to body of penis or clitorisBulbocavernosus, to body of penis or clitoris External anal sphincter, to circumanal, fecal External anal sphincter, to circumanal, fecal

continence, S2S4, Pud. N.continence, S2S4, Pud. N.

Male Urogenital traingleMale Urogenital traingle PenisPenis

Vascular Erectile Vascular Erectile tissues: tissues:

a.corpus spongiosum a.corpus spongiosum (urethra)(urethra)

b.Corpora cavernosab.Corpora cavernosa- Prepuce or foreskin Prepuce or foreskin

attach to the ventral attach to the ventral raphe by the frenulumraphe by the frenulum

- Deep fascia of Buck, Deep fascia of Buck, invest the muscle from invest the muscle from the root to the glansthe root to the glans

- Blood from the internal Blood from the internal pudendal artery, pudendal artery,

- pudendal nerve supplypudendal nerve supply

ScrotumScrotum

Labial scrotal fold Labial scrotal fold suspended from the suspended from the perineumperineum

Dartos layer formed by the Dartos layer formed by the fusion of the superficial fusion of the superficial and deep layers of the and deep layers of the superficial fascia. Muscles superficial fascia. Muscles that are temperature that are temperature sensitive for regulate.sensitive for regulate.

Nerve by the Ilioinguinalk, Nerve by the Ilioinguinalk, genitofemoral and dorsal genitofemoral and dorsal nerves of penisnerves of penis

External female genitaliaExternal female genitalia

Vulva, consist of the genital Vulva, consist of the genital labia and the urogenital sinuslabia and the urogenital sinus

Labia majora from the labio-Labia majora from the labio-scrotal foldscrotal fold

Uroginetal sinus or vestibule, Uroginetal sinus or vestibule, Fossa navicularis, Fossa navicularis,

Greater vestibular Greater vestibular gland( Bartholins glands-gland( Bartholins glands-glands of Cowper in males) glands of Cowper in males)

Paraurethral glands (Skene Paraurethral glands (Skene glands –prostate in males)glands –prostate in males)

Clitoris, corpora cavernosa, Clitoris, corpora cavernosa, prepuce, bulbocaverrnos prepuce, bulbocaverrnos musclemuscle

Blood by the internal Blood by the internal poudendal arterypoudendal artery

Fascia of the female urogenital Fascia of the female urogenital triangletriangle

Cruveilhers fascia – a fatty layer Cruveilhers fascia – a fatty layer continuous with Camper’s fasciacontinuous with Camper’s fascia

Colle’s fascia – deeper layer of Colle’s fascia – deeper layer of superficial fascia continuous with superficial fascia continuous with Scarpa’s fasciaScarpa’s fascia

Deep investing fascia of Gallaudet- Deep investing fascia of Gallaudet- covers the muiscles of the superficial covers the muiscles of the superficial pouchpouch

Internal female genitaliaInternal female genitalia

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