Pelvis and Perineum Hit List - Andrea Conway 09/17/06

1. posterior fornix of vagina

• A recess formed by the lumen of the vagina fusing around the cervix of the uterus
• Located at superior/posterior end of vagina
• Deeper than anterior or lateral fornices
• Wall is covered by peritoneum of the retrouterine pouch

2. central tendon (perineal body)

• Area between the opening of the vagina and the anus
• OR, area between the opening of the anus and the bulb of the penis

3. arcus tendineus

• Facial specialization of obterator internus muscle
• Strong band stretches from ischial spine to superior pubic ramus
• Gives origin to levator ani muscles
• Continues inferiorly to form arcus tendineus of pelvic fascia?

4. seminal vesicle

• Simple tubular glands located posterior/inferior to urinary bladder in males
• Secretes significant portion of what ultimately becomes semen
• Ducts open into the vas deferens as it enters the prostate gland

5. Mesosalpinx

• Portion of the broad ligament that stretches from the uterine tube to the level of the ovary

6. pampiniform plexus

• Consists of 8-10 veins lying in front of ductus deferens
• Formed by veins from the testicle and epididymus
• Posterior portion of the testicle

7. bulbospongious muscle

• In the female:
  • Attached posteriorly to perineal body
  • Fibers pass anteriorly around vagina and insert into copora cavernosa clitoris
• In the male:
  • Origin is at central tendon (perineal body) and extension of median raphe
  • Posterior fibers end in connective tissue of fascia of UG diaphragm; middle fibers encircle bulb of penis and corpus spongiosum; anterior fibers spread over side of corpus cavernosum
    

8. deep dorsal vein of penis

• Located on dorsal surface of penis within the deep fascia (Buck’s fascia)
• Unpaired

9. detrusor muscle

• Musculature of the bladder
• Consists of interlacing network of smooth muscle bundles

10. interuretic fold

• A ridge in the muscosa of the bladder between the two ureteric ostia
• “base” of vesical trigone

11. pelvic splanchnic nerve

• Parasympathetic innervation of the hindgut
• Derived from S-2 to S-4 segments of the spinal cord
• Enter the pelvic plexus (or inferior hypogastric plexus)

12. round ligament (ligamentum teres) of uterus

• Fibromuscular band that passes retroperitoneally from the uterus to the deep inguinal ring
• After traversing inguinal canal, ligament breaks up into fibrous strands that merge with connective tissue of labium majus

13. transverse rectal fold

• Three “semilunar” folds that project into lumen of rectum from its lateral walls
• Located in the depths of each lateral curvature

14. cremaster muscle and fascia

• Continuation of internal oblique, carried along the spermatic cord to the scrotum
• Located between external and internal spermatic fascia

15. inferior rectal artery

• Branch of internal pudendal artery
• Provides arterial supply to the anus, ischioanal fossa
• Anastomoses with middle rectal artery and superior rectal artery

16. obturator internus muscle

• Originates on internal surface of obterator membrane and margin of obterator foramen
• Inserts on greater trochanter
• Laterally rotates/abducts thigh
• Leaves the pelvis by passing through lesser sciatic foramen

17. ovarian ligament

• A band of connective tissue that connects the ovary to lateral surface of the uterus
• Lies within the mesovarium
• Remnant of the gubernaculum
• Continuous with the round ligament of uterus at the lateral surface of the uterus

18. suspensory ligament of penis

• Specialization of deep fascia connecting the proximal end of the penis to the pubis and pubic symphysis
• Fundiform ligament is a specialization of superficial fascia (Scarpa’s) that lies superficial to the suspensory ligament

19. arcuate ligament (of the pubis?)

• Located along the inferior border of the symphysis pubis
• Located anterior to the deep dorsal vein of the penis or clitoris and posterior to the suspensory ligament

20. dorsal nerve of penis

• Located on the dorsal shaft of the penis (paired), lateral to the dorsal arteries and deep dorsal vein within the deep fascia (Buck’s fascia)

21. perineal membrane

• Stretches across urogenital triangle, attaching to both ischiopubic rami
• Pierced by the urethra, vagina, and branches of pudendal neurovascular bundle
• Membranous layer of the deep perineal fascia
• Separates deep and superficial perineal pouches

22. piriformis muscle

• Originates on anterior surface of sacrum
• Inserts on upper border of greater trochanter
• Laterally rotates and abducts the thigh
• Leaves the pelvis by passing through the greater sciatic foramen

23. superior gluteal artery

• Branch of internal iliac artery, posterior division
• Provides arterial supply to the gluteus medius, gluteus minimus, and hip joint
• Passes superior to piriformis muscle; passes through greater sciatic foramen
• emerges between S1 and lumbosacral nerve roots

24. uterine artery

• Branch of internal iliac artery, anterior division
• Provides arterial supply to the uterus, uterine tube
• Anastomoses with vaginal artery and ovarian artery
• Passes superior to the ureter in the pelvis

25. anal column

• Located in the anal canal, terminal part of the alimentary tract
• Approximately halfway up the canal, the mucosa is raised into a row of 6-10 folds that encircle the canal => anal valves
• At the meeting of adjacent valves, mucosa is raised into longitudinal folds that extend into upper part of the canal => anal columns

26. broad ligament (mesometrium)

• Peritoneal fold extending from the pelvic walls to the uterus and uterine tubes
• Mesometrium is the part below the junction of mesovarium and mesosalpinx; attaches the body of the uterus to the pelvic wall

27. iliococcygeus muscle

• Originates from the arcus tendineus levator ani and the ischial spine
• Inserts on the anococcygeal raphe and coccyx
• Elevates the pelvic floor
• Combination of puborectalis, pubococcygeus and iliococcygeus is called the levator ani muscle

28. internal pudendal artery

• Branch of internal iliac, anterior division
• Important branches of this artery include: inferior rectal artery, perineal artery, artery of the bulb of penis/clitoris, urethral artery, deep clitoral/penile artery, dorsal clitoral/penile artery
• Provides arterial supply for the anus, muscles of superficial and deep perineal spaces, clitoris/penis, posterior aspect of the scrotum/labium majus
• Primary blood supply to perineum

29. puboprostatic ligament

• Strong ligament running from the posterior surface of the pubic bone (lateral to the pubic symphysis) to the prostate
• Lends support to the prostate
• Condensation of visceral pelvic fascia (lae2)
  

30. uvula of bladder

• In the male; a smooth, small eminence at the inferior corner of the vesical trigone (2 ureteric ostia + internal urethral orifice) just above the internal urethral orifice
• With advancing age, it becomes exaggerated due to enlargement of underlying median lobe of prostate

31. crus of clitoris

• Lateral part of the corpus cavernosum which is attached to the ischiopubic ramus and the perineal membrane
• Covered on its superficial surface by ischiocavernosus muscle

32. deep artery of penis

• Branch of internal pudendal artery
• Provides arterial supply to the corpus cavernosum of the penis
• Deep and dorsal arteries of the penis are terminal branches of internal pudendal artery

33. efferent ductule

• Connects the rete testis (duct system the seminiferous tubules discharge their contents into on posterior border of testis) to the epididymis
• located near the superior pole of the testis

34. head of epididymis

• Located on the superior pole of the testis
• Made up of 10 to 20 lobules, each consisting of an efferent ductile that becomes highly convoluted after leaving the testis

35. inferior fascia of UG diaphragm

• Covers the inferior surface of the urogenital diaphragm (muscle spanning the triangular space bordered on each side by conjoint rami of ischium and pubis)
• Fuses with the superior fascia of UG diaphragm along the anterior and posterior margins of the muscle

36. inferior gluteal artery

• Branch of internal iliac artery, anterior division
• Provides arterial supply to the gluteus maximus muscle and hip joint (cruciate anastomoses)
• Passes inferior to piriformis muscle to reach destination; passes through greater sciatic foramen

37. prepuce of clitoris

• Fold of smooth skin extending over the clitoris
• Anterior divisions of the labia minora combine to form the prepuce of clitoris

38. pudendal nerve

• Branch of ventral primary rami of spinal nerves S2-S4 (sacral plexus)
• Important branches include: inferior rectal nerve, perineal nerve, dorsal nerve of clitoris/penis
• Motor supply: external anal sphincter, bulbospongiosus muscle, ischiocavernosus, superficial and deep transverse perineal muscles, sphincter urethrae muscle, urethrovaginalis sphincter,
• Sensory: skin of anus, posterior scrotum/labium majus, clitoris/penis
• Passes through pudendal canal

39. Buck's fascia

• Deep fascia of the penis
• At the root of the penis, attaches laterally to ischiopubic rami and posteriorly to the margin of the UG diaphragm
• Does not descend into scrotum
• Contains the deep dorsal vessels of the penis

40. crus of penis

• Each crus is attached to ischiopubic ramus
• Right and left crura join the corpus spongiosum in the region of the pubic arch
• They come to lie side by side, forming the corpus cavernosum
• Ischiocavernosus muscle invests the crura of corpus cavernosum

41. darto's tunic

• Continuation of membranous layer of the superficial fascia from the abdominal wall into the scrotum
• Devoid of fat, but contains smooth muscle fibers
• Dartos extends inward as scrotal septum (partition between right and left halves of scrotum)
• Continuous with superficial penile fascia and with superficial fascia of the perineum

42. deep dorsal vein of clitoris

• An unpaired vein that runs between the two dorsal arteries of the clitoris deep to the deep fascia
• It leaves the perineum through the gap between the transverse perineal ligament and the arcuate pubic ligament and joins the vesical plexus; it communicates with tributaries of the internal pudendal veins

43. ejaculatory duct

• Pierces the posterior surface of the prostate and open into the prostatic urethra in the colliculus seminalis on each side of the utricle
• duct formed by the union of the duct of the seminal vesicle and the ampulla of the ductus deferens
• Less than 1 inch long

44. external pudendal vein

• Part of the drainage of the superficial dorsal vein of the clitoris/penis
• Deep external pudendal vein drains into the femoral vein; Superficial external pudendal vein drains into the great saphenous
• Drains skin and superficial fascia, pubic region

45. external spermatic fascia

• Derived from the fascias of external oblique
• Contributes to fascial coverings of spermatic cord
• Superficial to the cremasteric muscle/fascia and internal spermatic fascia
• Continues into the scrotum enclosing the tunica vaginalis and testis (fusion makes the three layers difficult to separate)

46. fundiform ligament

• see suspensory ligament of penis

47. inguinal ligament

• A band running from the pubic tubercle to the anterior superior iliac spine
• Forms the base of the inguinal canal
• Formed by the external oblique aponeurosis and is continuous with fascia lata of the thigh

48. ischiococcygeus (Coccygeus)

• Coccygeus is a thin triangular sheet of muscle continuous with the iliococcygeus muscle
• Anteriorly it originates from the ischial spine and sacrospinous ligament
• Inserts on lower sacral margin and coccyx
• Combines with levator ani muscle to form the pelvic diaphragm

49. levator ani

• Originates from the posterior surface of the body of the pubis, fascia of the obterator internus muscle (arcus tendineus levator ani), and ischial spine
• Inserts on the anococcygeal raphe and coccyx
• Elevates the pelvic floor
• Arterial supply provided by the inferior gluteal artery
• The combination of puborectalis, pubococcygeus & iliococcygeus is the levator ani muscle; coccygeus and levator ani combined form the pelvic diaphragm

50. mesovarium

• Part of the broad ligament that forms a shelf-like fold supporting the ovary
• Attaches ovary to mesometrium and mesosalpinx
• Located perpendicular to the plane of mesometrium and mesosalpinx

51. obturator artery

• Branch of internal iliac artery, anterior division
• Important branches include: pubic, acetabular, anterior, posterior
• Anterior and posterior branches pass on the anterior and posterior sides of adductor brevis muscle

52. pelvic diaphragm

• Composed of muscle fibers from levator ani muscles anterolaterally and coccygeus muscle posteriorly
• Its halves form the sloping floor of the pelvis, through which the urethra, vagina, and anal canal pass into the perineum
• Anterior deficiency in the pelvic diaphragm is the urogenital hiatus
• Important in providing support for pelvic viscera and maintaining continence of urine and feces

53. prostatic urethra crest

• Located on the posterior wall of the prostatic urethra
• Is presented as a longitudinal ridge raised up by a continuation of the trigonal muscle into the urethra
• The crest is continuous above with the uvula of the bladder

54. pubococcygeus

• Originates on the posterior aspect of the superior pubic ramis
• Inserts on the coccyx
• Elevates the pelvic floor
• Arterial supply is from the inferior gluteal artery
• the combination of puborectalis, pubococcygeus and iliococcygeus is called the levator ani muscle

55. pubovesical ligament

• Ligament extends from the bladder neck to the inferior aspect of the pubic bones
• Equivalent to the puboprostatic ligament in males
• Blends medially with the visceral fascia of either the prostate, bladder, vagina, or cervix and laterally with superior fascia of the pelvic diaphragm

56. sacral plexus

• Lower part of the lumbosacral plexus
• Lumbosacral trunk and sacral anterior rami can be considered the roots of the plexus
• Takes form on the posterior wall of the pelvis, just lateral to the pelvic foramina of the sacrum
• Major part of the plexus lies on the anterior surface of the piriformis muscle
• All larger branches pass through the greater sciatic foramen, most below the piriformis to appear in the buttock
• Sends off the pudendal nerve, the chief somatic nerve of the perineum

57. ureter

• Muscular tube that serves as the duct of the kidney to carry urine to the bladder
• Continuous proximally with the renal pelvis
• It passes over the pelvic brim medial to the testicular/ovarian vessels
• Passes obliquely through the posterior wall of the urinary bladder, and drains at the posterolateral angle of the vesical trigone (ureteric ostia)

58. uterine tube

• AKA fallopian tubes
• Bilateral ducts that extend from the uterus to the ovary
• Connect the uterine cavity to the peritoneal cavity
• Four parts: Infundibulum (funnel or trumpet shaped lateral expansion), presents fimbriae; ampulla (wide, thin-walled); isthmus (more narrow as move towards uterus); and uterine part (traverses thick uterine wall and through uterine ostium enters uterine cavity)

59. vas deferens

• AKA ductus deferens
• Conveys spermatozoa and secretions produced by the testis to the ejaculatory ducts
• Commences behind the lower pole of the testis as the continuation of the duct of the epididymis
• Ascends in the scrotum behind the testis and then the spermatic cord
• Enters the superficial ring of the inguinal canal and leaves through the deep ring
• At the deep ring the duct bends medially and pursues course toward the prostate

Comments and Suggestions

• Andrea. This is a great resource. An enhancement might be if the order followed a theme. Thank you. -- LorenEvey - 17 Sep 2006 - 22:17