Urogenital System PDF

PMS Block Anatomy ANATOMY OF URINARY& GENITAL SYSTEM BY DR HAIDY REFAAT D E PA R T M E N T O F H U M A N A N AT O M Y A N D E M B R Y O L O G Y FA C U LT Y O F M E D I C I N E...

PMS Block Anatomy ANATOMY OF URINARY& GENITAL SYSTEM BY DR HAIDY REFAAT D E PA R T M E N T O F H U M A N A N AT O M Y A N D E M B R Y O L O G Y FA C U LT Y O F M E D I C I N E ASSIUT UNIVERSITY  The urinary system is composed of 2 kidneys, 2 ureters, urinary bladder and urethra. The kidneys One on each side of the vertebral column. They extend from the level of the 12th thoracic vertebra to the level of the third lumbar vertebra. The right kidney is slightly lower than the left one. It has 2 surfaces, 2 borders, and 2 ends. The lateral border is convex; the medial border is convex at both ends and concave in the middle and presents the hilum of the kidney where the passage to the renal vessels and nerves and the pelvis of the kidney. The kidney is surrounded by a thin fibrous capsule. The tissue of the kidney is differentiated into an outer cortex and an inner medulla. The pelvis of the kidney is a dilated sac which extends outside the hilum to be continuous with the ureter. Coverings of the kidney: 1) Fibrous capsule is closely surrounds the kidney. 2)Perirenal (perinephric)fat: 3) Renal fascia. 4) Pararenal (paranephric) fat Arteries of kidneys The renal arteries arise from the aorta at L1. The ureter passes obliquely in the wall of the bladder for 1 inch before it opens into its cavity at the lateral angle of the trigone. This part of the ureter is the narrowest and is called the intramural part. 3 sites of constrictions, these sites are liable for stone impaction and they are: 1. At the pelvi-ureteric junction. 2. Where the ureter crosses the common iliac artery. 3. At the uretero-vesical junction. The urinary bladder : The urinary bladder is a hollow viscus with strong muscular wall which serves as a reservoir for urine. The capacity of the bladder is 220 cc of urine, but can accommodate up to 500 cc without discomfort. It lies in the lower and anterior part of the pelvis. Its shape is a three sided pyramid placed on one of its angles. The apex of the bladder is directed anteriorly immediately behind the upper border of the symphysis pubis, while its base is directed posteriorly. The neck is continuous with the urethra. The three surfaces of the bladder are one superior and two inferolateral. Each surface and the base are triangular in shape. The superolateral angles of the base are joined by the ureters, and the inferior angle gives rise to the urethra. In male, the neck rests on the prostate gland and continuous with the prostatic part of the urethera, in female it is continuous with the urethera. Internal urethral orifice: It is placed at the lowest part of the bladder. It is surrounded by an involuntary non-striated muscle forming the sphincter vesicae.  Male urethra: It is 20 cm long. It is divided into 3 parts: 1- The prostatic part: Is 3 cm long, begins at the neck of the urinary bladder. It is surrounded by the prostate. It is the widest and most dilatable part of the entire urethra. The ejaculatory ducts open into the prostatic urethra. 2- The membranous urethra: is one cm long. It is the narrowest, shortest and least dilatable part of male urethra. It is surrounded by the sphincter urethra. 3- The spongy part: is 16 cm long and is the longest part. It traverses the penis, and ends at the glans by the external urethra orifice (meatus). Female urethra: It is very short. It is about 4 cm long. It is wider and more dilatable than the male urethra. It begins at the neck of the bladder. Its upper part is surrounded by the sphincter urethra. MALE GENITAL SYSTEM The male reproductive organs are: the testes, epididymes, ductus deferens, seminal vesicles, ejaculatory ducts, prostate and bulbouretheral glands. The external genital organs are the penis, the urethera and the scrotum The testes: The testes are the primary sex organs in male. They lie in the scrotum (one on each side) where the temperature is less than that of the body which is suitable for the process of spermatogenesis (formation of spermatozoa). The testis is composed of numerous convoluted, seminiferous tubules. They produce the male sex cells (the sperms). From the upper part of the testis about 6-12 fine ducts (ductules) arise. They open into the duct of the epididymis The epididymis: It is a curved body applied to the posterior border of the testis. It is formed of a head, body and a tail. The head caps the upper pole of the testis where it is connected with the efferent ductules. Spermatozoa are stored and matured in the epididymis until ejaculated.  The vas deferens: Each vas deferens connects the duct of the epididymis to the urethera. It is 45 cm long. It ascends through the upper part of the scrotum to the abdominal wall, where it passes into the pelvis from the deep inguinal ring It descend & reach the base of the urinary bladder. It unites with the duct of the seminal vesicle to form the ejaculatory duct. The seminal vesicle: The seminal vesicles are two pear shaped lobulated pouches on each side of the base of the urinary bladder, They secrete alkaline secretion of the seminal fluid. Each is 5 cm long. Their ducts unite with the vas deferens to form the ejaculatory ducts. The ejaculatory ducts: Each ejaculatory duct is 2 cm long and pierces the prostate to open into the prostatic urethra close to its fellow The prostate: The prostate is a fibromuscular accessory gland which encircle the neck of the urinary bladder. The base is directed upwards, continuous with the neck of the urinary bladder. The apex is directed downwards. The bulbouretheral glands: A pair of pea sized yellowish glands. They lie within the fibers of the sphincter urethra. Their ducts open into the spongy part of urethra. The penis: The penis if formed of two main parts the root which lies in the perineum and the body which is the free part of the penis. The scrotum: It is a bag of skin and subcutaneous tissue in which the testes lie. Female Genital System The female reproductive organs are two ovaries, two uterine tubes, a uterus and a vagina. The parts of external genitalia are clitoris, mons pubis, labia major, labia minora, greater vestibular glands and vaginal orifice Ovaries: The ovaries are present in the pelvis one on each side of the uterus. Each ovary is almond-shaped. It has smooth surface before puberty, and become irregular with aging. At birth each ovary contains about 200.000 immature ova, from puberty to the end of reproductive period; one ovum is released every other month from each of the two ovaries. The monthly release of an ovum is called ovulation.  Uterine tubes (Fallopian tubes): They are two tubes, one on each of the uterus. The uterine tube is about 10 cm long. The abdominal opening is funnel shaped (the infundibulum). The uterine tube receives the ovum from the ovary and propels it into the uterine cavity. The uterus: It is a hollow thick, muscular pear-shaped organ in which the fertilized ovum is implanted until the fetus is fully developed. The uterine tube receives the ovum from the ovary and propels it into the uterine cavity. It lies between the urinary bladder anteriorly and the rectum posteriorly. Above, it receives the openings of the uterine tubes; while below the uterus opens into the vagina. Divisions: The uterus is divided into 3 parts: 1- Fundus: It is the part above the entrance of the uterine tubes. 2- Body: It is the main part of the uterus. It narrows from the fundus to the cervix. 3 -Cervix: Is about 1 inch long So, the normal position of the uteruis is a position of anteversion anteflexion. In some abnormal condition the uterus may acquire a position of retroversion and retroflexion. Vagina: It is a musculomembranous canal which connects the uterus with the vestibule. It lies between the bladder and the urethera anteriorly and the rectum and anal canal posteriorly. It anterior wall is 7 cm and its posterior wall in 9 cm. Questions??