Ajajdjjcjkakjsjdj

1. Lecture 3
The posterior abdominal wall
10/4/2021 Human Anatomy 4 PH students

2. Introduction
• The posterior abdominal wall
consists
• Bones
• lumbar vertebrae
• sacrum
• ilium
• Muscles
• Psoas
• quadratus lumborum
• transversus abdominis muscle
• posterior part of the diaphragm
and its crura

3. Posterior abdomen…
• It is posterior to the abdominal part of GIT, as
well as the spleen and pancreas.
• Posterior abdominal viscera include:
– the abdominal aorta and its associated nerve
plexuses,
– the inferior vena cava,
– the sympathetic trunks, and lymphatic's.
– the lumbar plexus of nerves
– the suprarenal glands, kidneys and abdominal part of
ureters.

4. 4
10/4/2021 Human Anatomy 4 PH students

5. Lumbar vertebrae (L1-L5)
• Bodies are thick and robust and kidney shaped
• Transverse processes are thin and tapered
• Spinous processes are thick, blunt, and point
posteriorly
• Vertebral foramina are triangular
• Superior and inferior articular facets directly
medially
 Allows flexion and extension – rotation
prevented
By Merga Sh. (Anatomist) 5

6. Lumbar vertebrae
By Merga Sh. (Anatomist) 6

7. Muscles
• Psoas major
• O= the transverse processes, sides
of the bodies and intervertebral
discs of the 5 lumbar vertebrae
• passes with iliacus (Iliacus arises
from the inner surface of ilium)
under the inguinal ligament
• I=lesser trochanter fusing with
iliacus (iliopsoas)
• N= by L1, 2 and 3 inside the
abdomen
• A=flexes the hip joint
10/4/2021 Human Anatomy 4 PH students

8. Iliacus
• O - iliac fossa
• I - lesser
trochanter of
femur
• N=femoral
• A - hip flexion
8
10/4/2021 Human Anatomy 4 PH students

9. Psoas minor
• An occasional small
muscle belly with its long
tendon lying over the
psoas major
• O - transverse processes
and bodies of T12 and L1
• I - rim of acetabulum
• N=L1
• A - flexes lumbar
vertebrae
9
10/4/2021 Human Anatomy 4 PH students

10. Quadratus lumborum
• Lies lateral to psoas, running
between the iliac crest and R12
• It is a side flexor of the trunk
• Innervated segmentally by the
adjacent lumbar nerves
10/4/2021 Human Anatomy 4 PH students

11. 11
10/4/2021 Human Anatomy 4 PH students

12. Anatomy of the Urinary System
04/10/2021 By: Merga S. (MSc.) 12

13. Introduction
• Urinary System is one of the four
excretory systems in our body.
US consists of:
Two kidneys
Two ureters
The urinary bladder
The urethra
The kidneys do the major work of the US
The other parts of the system are mainly
passageways and storage areas.
04/10/2021 By: Merga S. (MSc.) 13

14. Anatomy of the kidney
• Are paired reddish, bean-shaped organs.
• Located just above the waist in the
retroperitoneal cavity.
• Lie at level between T12 to L5 in supine position
• Partially protected by (11th and 12th Lt kidney and
12th Rt. kidney) pairs of ribs.
• If these lower ribs are fractured they can
slice/move easily into the kidneys and create
significant, even life-threatening, damage.
• A typical kidney in an adult is:
 Length => 10–12 cm (4–5 in.) long,
 Width => 5–7 cm (2–3 in.)
 Thickness => 3 cm (1 in.).
 Weight =>125–170 g (about 0.5% of TBW)
04/10/2021 By: Merga S. (MSc.) 14

15. External Features
• Each kidney is bean shaped.
 It has upper & lower poles
 medial and lateral borders, and
 anterior and posterior surfaces
• The upper pole is broad & is in close
contact with the corresponding suprarenal
glands.
• The lower pole is pointed.
04/10/2021 By: Merga S. (MSc.) 15

16. 04/10/2021 By: Merga S. (MSc.) 16

17. Right Kidney
1. It is slightly lower than the
left, 2.5 cm lower than the left
pole. Why?
2. Related to rib 12th only
3. Farther from midline
4. Narrower and thicker
5. Its superior pole lies near to
trans-ploric plane
Left Kidney
1. Slightly higher than right kidney
2. Related to rib 11th and 12th
3. Nearer to midline
4. Slender and longer.
5. Its Hilum lies near the
transpyloric plane, approximately
5cm from the median plane
04/10/2021 By: Merga S. (MSc.) 17

18. Kidney: Location
• The right lies
somewhat lower
than left as it is
positioned under
liver
10/4/2021 Human Anatomy 4 PH students

19. • Protected by three connective tissue layers
 Renal fascia
• Attaches to abdominal wall
Adipose capsule
• Fat cushioning kidney
 Renal capsule
• Fibrous sac
• Protects from trauma and infection
Why kidney moves with respiration?
04/10/2021 By: Merga S. (MSc.) 19

20. 04/10/2021 By: Merga S. (MSc.) 20

21. Relations of the
Kidneys
Anterior Posterior
Left Kidney Spleen
Stomach
Suprarenal gland
Pancreas
Small intestine
(Duodenum, jejunum and
ileum)
Left colic flexure
Splenic artery
Splenic vessels
11th and 12th ribs
Diaphragm
Quadratus lumborum
Transversus abdominis
Psoas major
Subcostal vessels
Subcostal nerves
Iliohypogastric nerve
Ilioinguinal nerve
Right Kidney Right suprarenal gland
Right lobe of liver
Right colic flexure
Small intestine
Duodenum
As for left except no 11th
rib
21

22. Figure: Structures related to the anterior surface of each kidney
22

23. Figure: Structures related to the posterior surface of each kidney.
23

24. 04/10/2021 By: Merga S. (MSc.) 24

25. Relations…posterior surface
04/10/2021 By: Merga S. (MSc.) 25

26. By: Merga S. (MSc.) 26

27. Hilum Of Kidney
On the medial margin of each kidney
Is a deep vertical slit
Through which renal vessels, lymphatics, and
nerves enter and leave the substance of the
kidney.
• At the hilum, the renal vein is anterior to the renal
artery, which is anterior to the renal pelvis.
i.e from anterior to posterior:-VAP
(Renal Vein -----> Renal Artery ----> Renal Pelvis)
04/10/2021 By: Merga S. (MSc.) 27

28. 04/10/2021 By: Merga S. (MSc.) 28

29. Internal Anatomy
• The kidney has
three distinct
regions
– Cortex
– Medulla
– Pelvis
10/4/2021 Human Anatomy 4 PH students

30. Internal Anatomy of the Kidneys.
Gross Appearance
1. Renal Cortex:
• Is a continuous band of pale tissue
• A superficial, light red area
2. Renal Medulla (a deep, darker red-brown region).
• Renal Columns are extensions of the renal cortex
Project into the inner aspect of the kidney
Dividing the renal medulla into discontinuous
aggregations of triangular-shaped tissue called
(the renal pyramids)=extensions of the renal
medulla
04/10/2021 By: Merga S. (MSc.) 30

31. 04/10/2021 By: Merga S. (MSc.) 31

32. 2. Renal Pyramids
 Their bases are directed outward, towards the renal cortex,
 Their apex (renal papilla) projects inward, towards the renal sinus.
 Each renal papilla is surrounded by a minor calyx.
3. Minor Calices (8-18 for each kidney) : receive urine
 Represent the proximal parts of the tube that form the ureter
 Unite to form a major calyx
4. Major Calyx: (2-3 for each kidney)
 Two or three major calices unite to form the renal pelvis (the
funnel-shaped superior end of the ureters).
5. Renal Pelvis: Superior dilated end of ureter.
 Formed by condensation of 2 or 3 major calices.
 Narrows as it passes inferiorly through the hilum of the
kidney.
 Continuous with the ureter at the ureteropelvic junction
04/10/2021 By: Merga S. (MSc.) 32

33. • The pyramids and their associated Cortex form the lobes of
the kidney. The lobes are visible on the external surfaces
of the kidneys in fetuses or infant and disappear by age
increases/very large adrenal glands and lobulated
kidneys in infants.
04/10/2021 By: Merga S. (MSc.) 33

34. Blood supply/renal vasculature
• Arterial Supply: Renal arteries which
are the direct branches of abdominal aorta
& are large in size.
• Venous Drainage: Renal veins, ends
in inferior vena cava. The left renal
vein is longer than the right. Why?
• Nerve Supply: Sympathetic fibers
derived from T10,L1 segments and
parasympathetic fibers from vagus
nerve.
• Lymphatic drainage: into lateral
aortic nodes.
04/10/2021 By: Merga S. (MSc.) 34

35. • Renal Blood Vessels
Arterial blood from AA enters the kidney through the Renal
Artery Segmental Arteries Interlobar Arteries
Arcuate Arteries  Interlobular  Afferent
Arterioles Glomeruli Capillary  Efferent
Arterioles Peritubular Capillaries Inter Lobular
Veins  Arcuate Veins  Interlobar Renal Veins
Inferior Vena Cava  Heart
04/10/2021 By: Merga S. (MSc.) 35

36. 04/10/2021 By: Merga S. (MSc.) 36

37. Ureters
• Thick walled muscular
duct with narrow
lumina
• Carry urine from
kidneys to urinary
bladder
• It measures 25cm (10
in.)
10/4/2021 Human Anatomy 4 PH students

38. Ureters
• Each leaves the renal pelvis, descends behind the
peritoneum to the base of the bladder, turns and
then runs obliquely through the medial bladder
wall
• Abdominal part
• runs down anterior to the psoas major,
retroperitoneally
• Right ureter lies closely related to inferior vena
cava, lumbar lymph nodes and sympathetic trunk
• Inferiorly, testicular or ovarian vessels cross over
the ureter
• Crosses pelvic brim and external iliac artery just
beyond bifurcation of common iliac arteries
10/4/2021 Human Anatomy 4 PH students

39. Ureters
10/4/2021 Human Anatomy 4 PH students

40. Obstruction of ureter
• Obstruction results from ureteric calculus (kidney
stones)
• Ureters dilate if obstructed
• Excessive distension causes severe pain – ureteric
colic, results from hyper-peristalsis in ureter
• Causes complete or intermittent obstruction of
urinary flow
• Occur any where along ureter, but often in the 3
narrow regions
• at the junction with the pelvis of the kidney
• where it crosses the brim of the pelvic bone
• as it enters the bladder
10/4/2021 Human Anatomy 4 PH students

41. Anatomical constriction site of ureter

42. • Arterial supply: It is well supplied by the
renal artery, aorta, gonadal arteries and
various pelvic vessels.
• Venous drainage: Testicular and ovarian
veins
• Lymphatic drainage: aortic, common
iliac, external iliac and internal iliac
lymph nodes
• Innervation: renal , testicular/ovarian,
inferior hypogastric plexus
10/4/2021 Human Anatomy 4 PH students

43. Abdominal aorta
• Continuation of thoracic aorta
• Lies in the midline against vertebral bodies
• It enters the abdomen through aortic hiatus
at T12 and L1 level
• Ends at L4, left of the midline by dividing into
the 2 common iliac arteries.
• The main continuation of the aorta is the
median or middle sacral artery
10/4/2021 Human Anatomy 4 PH students

44. 10/4/2021 Human Anatomy 4 PH students

45. Abdominal aorta: relations
• Superior: diaphragm
• Anterior: celiac trunk and plexus,
pancreas, left renal vein, duodenum,
mesentry
• Posterior: bodies of L1-L4 vertebrae,
cisterna chili
• Lateral: inferior vena cava (right), left
ciliac ganglion, sympathetic trunk
10/4/2021 Human Anatomy 4 PH students

46. 46
10/4/2021 Human Anatomy 4 PH students

47. Abdominal aorta: Branches
• Subdivided into groups of 4:
– 3 unpaired visceral
– 3 paired visceral
– paired parietal
– unpaired parietal
10/4/2021 Human Anatomy 4 PH students

48. Branches
• Inferior phrenic:
T12
• Celiac trunk:
T12/L1
• SMA: L1
• Renal & Gonadal:
L2
• IMA: L3
• Bifurcation: iliac
L4
10/4/2021 Human Anatomy 4 PH students

49. 10/4/2021 Human Anatomy 4 PH students

50. Unpaired visceral branches
• Ventral branches; arise from
anterior surface
• arteries to the fore-, mid- and
hindgut respectively
• celiac trunk
• superior mesenteric
• inferior mesenteric
• Coeliac trunk:
• Foregut oesophagus to D2
• Superior mesenteric
• Midgut D3 to distal 1/3
transverse colon
• Inferior mesenteric
• Hindgut distal 1/3 transverse
colon to upper 2/3 of rectum
10/4/2021

51. Paired visceral branches
• Arise from sides; lateral branches
• Supply the suprarenal glands, kidneys and
the gonads
• Renal arteries
• Arise just below the superior mesenteric
artery
• The right renal artery passes posterior to
the inferior vena cava
• They also send branches to the suprarenal
glands and the renal pelvis
• Pass to hilum of kidney between ureter
and renal vein
10/4/2021 Human Anatomy 4 PH students

52. • Gonadal (ovarian or testicular) arteries
• Arise from the aorta just below the renal
arteries
• They descend lying anterior to the surface of
the psoas to reach the ovary or pass into the
inguinal canal to go to the scrotum
• Middle suprarenal arteries
• Arise near the origin of SMA
10/4/2021 Human Anatomy 4 PH students 52

53. Paired parietal branches
• Arise from postero-lateral surface
• Are branches to the body wall
• The inferior phrenic arteries
– Gives branch to the suprarenal gland and ramify
on the inferior surface of the diaphragm
• The 4 lumbar arteries
– gives a posterior branch going through the back
and giving a spinal branch
– The anterior branch runs in the anterior
abdominal wall between the transversus and the
internal oblique muscle
10/4/2021 Human Anatomy 4 PH students

54. Unpaired parietal branches
• Arise from posterior surface
• The median (middle) sacral artery
– in the midline, anterior to the sacrum
– from bifurcation of aorta
10/4/2021 Human Anatomy 4 PH students

55. Inferior Vena Cava
• Returns blood from lower limbs,
abdominal wall and abdomino-pelvic
viscera
• begins in front of the body of L5 by
union of common iliac veins
• ascends, on right psoas muscle right to
aorta, to the diaphragm
• pierce the central tendon at T8 forming
vena caval foramen
• Relations
• posterior: bodies of L3-L5, right
psoas major muscle, right
sympathetic trunk, right renal artery,
right suprarenal gland
• anterior: superior mesenteric vessels,
head of pancreas, duodenum
• lateral: aorta (left), right ureter and
kidney (right)
10/4/2021 Human Anatomy 4 PH students

56. Tributaries
• Ventral tributary: right testicular or
ovarian vein
• Lateral tributaries: renal and right
suprarenal and hepatic veins
• Correspond to the named arteries except on
the left where the suprarenal and gonadal
veins open into the left renal vein
• Tributaries from the body wall: the inferior
phrenic and lumbar veins
• the median sacral opens into the left
common iliac vein
10/4/2021 Human Anatomy 4 PH students

57. 10/4/2021 Human Anatomy 4 PH students

58. Lumbar plexus
• Lies in the psoas major
• Formed by the anterior primary rami of L1, 2, 3, and 4
• The sacral plexus is from L4, 5, S1, 2, 3 and 4
• L4 is also called the nervus furcalis or lumbosacral
trunk because it splits itself between the lumbar and
sacral plexuses
• The sacral and lumbar plexuses overlap substantially
• Since many of the fibers of the lumbar plexus
contribute to the sacral plexus via the lumbosacral
trunk, the two plexuses are often referred to as the
lumbosacral plexus
10/4/2021 Human Anatomy 4 PH students
reading assignment

59. Branches
• Its proximal branches innervate parts of
the abdominal wall and iliopsoas
• Major branches of the plexus descend
to innervate the medial and anterior
thigh
• branches
• iliohypogastric nerve
• ilioinguinal
• The genitofemoral nerve
• The lateral cutaneous nerve of the thigh
• The femoral nerve
• The obturator nerve
10/4/2021 Human Anatomy 4 PH students

60. Branches
• Iliohypogastric nerve
• Supply skin of inguinal region
• Ilioinguinal
• This runs between the layers of the anterior abdominal
wall
• emerges from the superficial inguinal ring
• supplies the skin on the medial side of the thigh and the
scrotum or labium majus
• Genitofemoral nerve
• emerges from the anterior surface of the psoas major
• runs down deep to the psoas fascia
• supplies cremaster muscle via its genital branch and a
small area under the inguinal ligament by its femoral
branch
• Lateral cutaneous nerve of the thigh
• emerges from the lateral border of the psoas
• sweeps around the iliac fossa and leaves the abdomen by
passing under the inguinal ligament
60
10/4/2021 Human Anatomy 4 PH students

63. • Femoral nerve
• large and emerges from the lateral border
of psoas
• may give branches to psoas and iliacus
• It lies outside of the fascia covering psoas
and iliacus
• Obturator nerve
• emerges from the medial border of the
psoas near the brim of the pelvis
• lying posterior to the common iliac vessels
• It then travels anteriorly and inferiorly,
anterior to obturator internus and leaves
the pelvis by passing through the superior
part of the obturator foramen
10/4/2021 Human Anatomy 4 PH students 63

64. 64
10/4/2021 Human Anatomy 4 PH students

65. 10/4/2021 Human Anatomy 4 PH students

66. The autonomic nervous system in the abdomen
• The paravertebral chain of ganglia
• found along the anterior border of the psoas
• White rami from the first 2 lumbar nerves pass to the
ganglia and all ganglia have gray fibers passing back to
the lumbar nerves
• Celiac ganglia and plexuses
• lie around the celiac and mesenteric arteries
• Plexuses are joined by the 3 splanchnic nerves, branches
of the vagus nerves (parasympathetic) and branches from
the sympathetic trunk
• Postganglionic sympathetic fibers from plexuses travel
with all the major arteries, along with preganglionic
parasympathetic fibers to innervate viscera
• Plexuses around the aorta continue downward and
anterior to the aortic bifurcation forms the superior
hypogastric plexus
• This divides into the right and left inferior hypogastric
plexuses joined by the parasympathetic pelvic splanchnic
nerves (S2,3,4)
10/4/2021 Human Anatomy 4 PH students

67. 10/4/2021 Human Anatomy 4 PH students

70. By Merga Sh. (Anatomist) 70
THANK U FOR
YOUR
ATTENTION!!!!
!!!!!