Imaging Anatomy: The Pelvis and Male & Female Reproductive Systems

Comprehensive review flashcards covering imaging anatomy of the pelvis, pelvic inlet differences, female reproductive system, breast anatomy and lymphatics, and male reproductive system based on RADI1225 lecture materials.

What three bones constitute the bony pelvis?

The two hip bones (innominate or pelvic bones), the sacrum, and the coccyx.

In this anatomical representation of the pelvis, what structures correspond to labels 1, 2, and 3?

Label 1 corresponds to the hip bones (innominate or pelvic bones), label 2 corresponds to the sacrum, and label 3 corresponds to the coccyx.

What are the four articulations found within the pelvis?

Two sacroiliac joints (between the ilium of the hip bones and the sacrum), the sacrococcygeal symphysis (between the sacrum and coccyx), and the pubic symphysis (between the pubis bodies of the two hip bones).

What are the primary functions of the pelvic girdle?

Transferring weight from the upper axial skeleton to the lower appendicular skeleton during movement, providing attachments for muscles and ligaments used in motion, and protecting abdominopelvic and pelvic viscera (ileum, sigmoid colon, rectum, and reproductive organs).

How do the structural characteristics of the female pelvis differ from the male pelvis regarding width, ilia flare, pubic arch angle, and inlet shape?

The female pelvis is wider, broader, shallower back to front, has more flared ilia, a pubic arch angle $\gt 90^\circ$, and a large, round pelvic inlet; the male pelvis is narrower, deeper, less flared, with a pubic arch angle $\lt 90^\circ$, and a narrow, oval, or heart-shaped pelvic inlet.

Why is the bispinous diameter greater in the female pelvis than in the male pelvis?

The female pelvis possesses less prominent ischial spines, which creates a greater bispinous diameter to aid the process of childbirth.

Based on the shape and morphology shown in this 3D rendering, how do the female and male pelvic inlets differ?

The female pelvic inlet (left) is large and round with a wider pelvic brim, whereas the male pelvic inlet (right) is narrower and heart-shaped or oval.

What distinguishes the greater (false) pelvis from the lesser (true) pelvis?

The greater pelvis is the superior portion that supports the lower abdominal viscera (ileum and sigmoid colon) with no obstetric relevance; the lesser pelvis is the inferior portion that contains the pelvic cavity and pelvic viscera.

What is the pelvic inlet and what constitutes the pelvic brim?

The pelvic inlet is the junction between the greater and lesser pelvis; its outer bony edges are termed the pelvic brim.

Which anatomical structures comprise the external female genitalia (vulva)?

The mons pubis, labia majora, labia minora, clitoris, vestibule, and mammary glands.

Where are the internal female reproductive organs situated within the pelvis?

Between the urinary bladder anteriorly and the rectum posteriorly, with the uterus and vagina located in the midline and the ovaries on either side of the uterus.

What are the location, dimensions, and ligamentous attachment of the ovaries during childbearing years?

They are paired oval organs measuring approximately $3\text{--}5\,\text{cm}$ in length, located on either side of the uterus within the broad ligament below the fallopian tubes, and connected to the uterus via the ovarian ligament.

How do the arterial supply and venous drainage differ between the right and left ovaries?

Both ovaries receive blood via right and left ovarian arteries arising directly from the descending aorta; however, the left ovarian vein drains into the left renal vein, while the right ovarian vein empties directly into the inferior vena cava.

What are the dimensions of the fallopian tubes, and where do they exit the uterus?

Each tube is approximately $10\,\text{cm}$ in length and $1\,\text{cm}$ in diameter, exiting the superior portion of the uterine cavity through the cornua within the mesosalpinx.

What are the three anatomical segments of a fallopian tube, and which is the most common site for fertilization?

The isthmus (closest to the uterus), the ampulla (more dilated segment and the most common site for fertilization), and the infundibulum (farthest from the uterus).

What are the four main sections of the uterus?

The fundus (widest, superior segment above the entrance of the fallopian tubes), corpus, isthmus, and cervix (lowest, cylindrical portion).

What is the primary arterial supply to the uterus, and what branches arise from it?

Blood is supplied by the uterine arteries (originating from anterior divisions of the internal iliac artery) and ovarian arteries; the uterine artery occasionally branches into the vaginal artery and arcuate arteries.

How do an anteverted uterus and a retroverted uterus differ in position?

An anteverted uterus is tipped forward relative to the vagina, whereas a retroverted uterus is tipped backward.

What is the difference between an anteflexed and a retroflexed uterus?

An anteflexed uterus has the fundus tilted forward, whereas a retroflexed uterus has the fundus tilted backward.

What anatomical tissues and structures make up the breast?

Lobules (milk-producing glands), ducts (tubes carrying milk to the nipple), fatty and connective tissue, areola (pigmented area with moisture-secreting sweat glands), and the nipple.

What are five reasons why breast compression is necessary during a mammogram?

To even out breast thickness for full tissue visualization, spread out tissue so abnormalities are not hidden, allow a lower x-ray dose, minimize blurring caused by motion, and reduce x-ray scatter to enhance sharpness.

What are the two standard radiographic projections used in screening mammography?

Cranio-caudal (CC) and medio-lateral oblique (MLO).

What are the three main lymphatic drainage pathways of the breast?

The axillary (lateral) pathway (draining the majority of lymph to the pectoral group of axillary nodes), the internal mammary pathway (passing through pectoralis major toward the contralateral breast), and the retro-mammary pathway (from the posterior breast).

What three main lymph node chains draining the mammary gland are shown in this diagram?

The axillary lymph nodes chain, the supraclavicular lymph nodes chain, and the internal mammary lymph nodes chain.

What are the three anatomical divisions of the penis?

The root (attaching to the abdominal wall), the body or shaft, and the glans (cone-shaped terminal portion with sensitive nerve endings).

What erectile chambers are visible in this transverse cross-section of the penis?

Two dorsal corpora cavernosa and one ventral corpus spongiosum surrounding the urethra.

How does the scrotum function as a climate control system for the testicles?

Special muscles in its wall contract or relax to move the testicles closer to the body for warmth or farther away for cooling, maintaining a temperature slightly cooler than core body temperature for normal sperm development.

What is the function of the seminiferous tubules, and what vessels provide blood supply and venous drainage to the testes?

Seminiferous tubules produce sperm cells; arterial supply is delivered via the testicular, cremasteric, and deferential arteries, while venous drainage is handled by the pampiniform plexus.

What are the structural role and functional purpose of the epididymis?

It is a long, coiled tube resting on the backside of each testicle that transports, stores, and brings sperm cells to maturity because sperm emerging from the testes are immature and incapable of fertilization.

What path does the vas deferens follow, and what is its role?

It is a long, muscular tube that travels from the epididymis into the pelvic cavity to just behind the bladder, transporting mature sperm to the urethra in preparation for ejaculation.

What fluid is produced by the seminal vesicles, and what is its physiological significance?

A sugar-rich fluid (fructose) that supplies sperm with energy for motility, constituting most of the volume of the ejaculate.

Where is the prostate gland located, and what is its role in male reproduction?

It is a walnut-sized organ located below the urinary bladder in front of the rectum that contributes additional nourishing fluid to the ejaculate.