Posterior Abdominal Wall and Diaphragm Flashcards
1
Q
What are the bones associated with the posterior adbomen?
A
5 lumbar vertebrae + associated intervertebral discs, XI and XII ribs, sacrum, ala (wing) of sacrum
2
Q
How do the lumbar vertebrae differ from the cervical and thoracic vertebrae?
A
lumbar vertebrae are much larger, their pedicles are short and stocky, their transverse processes are long and slender, and the spinous processes are large;
no costal facet like thoracic vertebrae; no transverse foramen like cervical vertebrae
3
Q
Which are the free/floating ribs? why?
A
XI and XII, because they do not fuse with the sternum or with eachother (costal cartilage like other false ribs)
4
Q
What is located inferior to the 5th lumbar vertebrae?
A
the upper margin of the sacrum (formed by the fusion of the five sacral vertebrae into a single wedge shaped structure)
5
Q
Describe the anterior and posterior surface of the sacrum
A
anterior = concave posterior = convex
6
Q
What forms the sacroiliac join (be specific!)
A
upper part of illium articulates with the ala transeverse process of S1 (sacral vertebrae 1)
7
Q
what is the promontory of the sacrum?
A
the anterior edge of S1 that projects forward
8
Q
Where is Rib XI located with respect to the kidney? (which kidney?)
A
located posterior to the superior part of the LEFT kidney
9
Q
where is rib XII located with respect the kidney? which kidney?
A
located posterior to the superior part of the LEFT and RIGHT kidneys
10
Q
What muscles make up the posterior abdominal wall? Where are they located with respect to each other?
A
Psoas Major + minor = medial
Quadratus lumborum = lateral
iliacus = inferior
diaphragm = superior
11
Q
Where is the psoas major muscle located with respect to the lumbar vertebrae?
A
lateral
12
Q
Where does the psoas major muscle tendon run with respect to the inguinal ligament? hip joint?
A
runs POSTERIOR to inguinal ligament;
ANTERIOR to hip joint
13
Q
what does the psoas major muscle insert on?
A
the lesser trochanter of the femur
14
Q
What is the origin of the psoas major muscle?
A
- bodies of all 5 lumbar vertebrae and + T12
2. transverse process + intervertebrael discs of lumbar vertebrae
15
Q
what is the psoas major muscle innervated by?
A
lumbar plexus (Ventral rami of L1 L2 L3)
16
Q
what is the action of the psoas major?
A
acting superior with iliacus: flexion of the thigh
acting inferior alone: flexion of the vertebral column laterally
acting with other psoas major + iliacus: flexion of the trunk
17
Q
what is the psoas minor attached to superiorly?
A
the sides of T12 and L1 + intervening intervertebral disc
18
Q
what is the psoas minor attached to inferiorly?
A
iliopubic eminence on the pelvic rim
19
Q
what is the psoas minor innervated by?
A
ventral ramus of L1
20
Q
where is the psoas minor located with respect to psoas major?
A
psoas minor is anterior to the psoas major
21
Q
what is the function of the psoas minor?
A
helps the psoas major to flex the pelvis and lumbar region of the vertebral column
22
Q
what is the chief flexor of the thigh?
A
iliopsoas (iliacus + Psoas major)
23
Q
where is the iliacus located with respect to the psoas major muscle?
A
lateral and inferior to the psoas major
24
Q
What is the origin of the iliacus?
A
superior 2/3 of the iliac fossa
25
what is the insertion of the iliacus?
join the fibers of the tenos od psoas major and attach to the lesser trochanter of the femur
26
what is the iliacus innervated by?
femoral nerve (L2, L3, L4)
27
what muscle extends across the sacroiliac joint?
iliacus
28
what is the function of the iliacus muscle?
flexes the thigh and stabilizes the hip joint with the psoas major
29
what is the iliopsoas? what is its action?
iliacus + psoas major
| action = chief flexor of the thigh + help to maintain erect posture at the joint
30
How is an abscess resulting from tuberculosis in the lumbar region related to the psoas muscle?
the abscess tends to spread from the vertebrae in the fascia enclosing the pasoas major muscle and could produce a psoraes abscess; pus from the abscess could pass inferiorly along the the psoas over the pelvic brim, deep to the inguinal ligament and into the femoral triangle
31
what overlaps the quadratus lumborum medially?
psoas major
32
what is the origin of the quadratus lumborum
tips of the transverse processes of all 5 lumbar vertebrae and the medial half of the inferior border of rib XII
33
what is the insertion of quadratus lumborum
iliolumbar ligament and internal lip of the iliac crest
34
what does the iliolumbar ligmanet connect?
the tips of L5 to the iliac crest
35
what is the innervation of quadratus lumborum
ventral branches of T12, L1, L2, L3, L4
36
what is the action of the quadratus lumborum
extends and laterally flexes the vertebral column; fixes rib XII during inspiration
37
what is the principal muscle of respiration?
diaphragm
38
what forms the floor of the thoracic cavity and roof of the abdominal cavity?
diaphragm
39
How does the diaphragm move during inspriation
descends; only the dome moves, the peripheral parts are unable to move because they are attached to the inferior margin of the osteocartilagenous thoracic cage and the superior lumbar vertebrae
40
why does only the dome of the diaphragm move during inspiration?
because the peripheral parts are unable to move because they are attached to the inferior margin of the osteocartilagenous thoracic cage and the superior lumbar vertebrae
41
what does the muscular portion of the diaphragm insert onto?
the central tendon (central aponeurotic part of the diaphragm)
42
what are the divisions of the diaphragm?
sternal, coastal, lumbar
43
what are the attachments of the sternal portion of the muscular diaphragm?
1. posterior aspect of the xiphoid process of the sternum
| 2. converge onto central tendon and form a sternocostal hiatus
44
what is the sternocostal hiatus? where is located? what forms it? what goes through it?
a small anterolateral gap formed by the sternal diaphragm muscle inserting on the central tendon of the diaphragm;
superior epigastric artery runs through it
45
what is the origin of the costal muscle fibers of the diaphragm?
the internal surface of the inferior six ribs on their costal cartilages on each side
46
what does the costal muscle fibers of the diaphragm form? what is their function?
form the right and left hemidiaphragm/domes;
| move during inspiration
47
what is the vertebrocostal triangle/trigone? what is it formed by? what is its contents in the living person?
an interval that separate costal part of the diaphragm that arises from the Xi and XII ribs from the lumbar part;
filled with loose CT in the adult
48
what is the origin of the lumbar muscle fibers of the diaphragm?
the lumbar vertebrae by two musculotendinous crura (L-Leg),
49
what are the left crus of the diaphragm attached to?
attached on each side of the aorta to the anterolateral surfaces of the superior two (left) or three (right) lumbar vertebrae and their intervertebral discs
50
how does the right crus differ from the left crus?
right = broader and longer than the left crus
51
Where are the crura of the diaphragm united? by what?
united opposite the disc between T12 and L1;
| by median arcute ligmanet = a tendinous band arch
52
what is the diaphragm attached to?
the medial and lateral arcuate ligaments
53
what are the medial arcuate ligaments formed by?
thickening of the psoas fascia over the superior part of the psoas major muscule
54
where do the medial arcuate ligaments radiate towrards?
the central tendon
55
what are the lateral arcuate ligaments formed by?
thickenings of the anterior layer of the thoracolumbar fascia over the superior part of the quadratus lumborum muscle;
56
what muscle does the medial arcuate ligament travel over? the lateral arcuate ligament?
```
medial = psoas major
lateral = quadratus lumborum
```
57
where do the lateral and medial arcuate ligaments unite?
the mediaN arcuate ligament
58
What is the central tendon? what does it fuse to? What are its divisions?
a strong aponeurosis that the muscle fibers of the diaphragm converge radially to;
It is fused with the inferior surface of the fibrous pericardium;
Divided into 3 areas which resembly a clover leaf
59
Where is diaphragmatic herniation most prone? what is caused by?
Herniation prone at areas where the diaphragm muscle fuses to the aponeurosis;
Herniation results from sudden increase in intrathoracic or intra-abdominal pressure (ie: car accident);
60
where do most diaphragmatic ruptures occur?
On the left side, through the weak vertebrocostal triangle (an area where muscle fibers of the costal and lumbar parts of the diaphragm fuse)
61
What is a congenital hernia?
an esophageal or sternocostal opening when the diaphragm ruptures and the stomach (most common), intestines, or spleen herniates into the thorax
62
At what thoracic level is the vena caval foramen located?
T8
63
what is the vena caval foramen? How does it function in inspiration?
a foramen that allows the inferior vena cava to descend through the diaphragm to the abdomen;
When the diaphragm contracts during inspiration, it widens the foramen and stretches and dilates the inferior vena cava
64
where is the esophageal hiatus located with respect to the (vena) caval opening?
posterolateral to the caval opening
65
what is the esophageal hiatus formed by?
the right crus
66
At what vertebral level is the esophageal hiatus located?
T10
67
What runs though the esophageal hiatus?
esophagus, anterior and posterior vagal trunks
68
what forms the esophageal sphincter?
muscle fibers of the right crus
69
what is the function of the esophageal sphincter?
it constricts the distal end of the esophagus during inspiration to prevent reflex of gastric contents into the esophagus;
the sphincter closes the esophagus when not eating to prevent stomach juices from getting back into the esophagus
70
Does the aorta pierce through the diaphragm?
NO
71
Is the aorta affected by contractions of the diaphragm during inspiration?
NO!! the aorta does NOT pierce the diaphragm (aorta hiatus is posterior to the mediaN arcuate ligament)
72
where is the aortic hiatus located?
posterior to the mediaN arcuate ligament
73
At what vertebral level is the aortic hiatus located?
T12
74
what runs through the aortic hiatus?
aorta, thoracic duct, azygous vein
75
where is the sternocostal hiatus located? what runs through it?
located between the sternal and costal parts of the diaphragm; the superior epigastric vessels usually pass through it
76
where do the subcostal nerves and vessels pass through the diaphragm?
posterior to the lateral arcuate ligaments
77
where does the sympathetic trunk pass through the diaphragm?
posterior to the medial arcuate ligament
78
where do the greater and lesser splanchnic nerves pass through the diaphragm?
they pierce the crura
79
where does the hemiazygous vein pass through diaphragm?
through the left crus of the diaphragm r medial arcuate ligament
80
what happens to the central tendon during inspiration?
the diaphragm contracts which brings the central tendon down, allowing the volume of the thorax to increase
81
where is diaphragm pain referred?
to shoulder because phrenic nerve = C3,4,5 (and C5 = part of brachial plexus)
+ costal margin of abdomen (due to sensory impulses traveling with the intercostal nerves)
82
what arteries supply the diaphragm superiorly?
superior phrenic branch of the thoracic aorta + musculophrenic (internal thoracic) + pericardiacophrenic (internal thoracic)
83
what arteries supply the diaphragm inferiorly?
inferior phrenic artery (from abdominal aorta)
84
what nerves innervate the diaphragm (motor + sensory)
1. phrenic nerve = sensory (pain/propriorecption) + motor
2. Intercostal nerve 6 + 7 (ventral spinal T6 + 7) = peripheral sensory
3. subcostal nerve (ventral spinal T12) = peripheral sensory
85
Describe the lymphatic drainage of the thoracic surface of the diaphragm
lymph nodes drain into the phrenic nodes and then parasternal and posterior mediastinal lymph nodes
86
Describe the lymphatic drainage of the abdominal surface of the diaphragm
drains into superior lumbar lymph nodes
87
What is the action of the diaphragm? what happens to the domes during contraction?
diaphragm = chief muscle of inspiration;
when it contracts, the right and left domes inferiorly which increases the volume of the thorax which allows air to be taken into the lungs
88
How is diaphragmatic contraction related to venous return?
when the diaphragm contract, the inferior vena cava dilates (due to the caval foramen) with allows the return of venous blood into the heart
89
How is the diaphragm related to abdominal straining?
it assists the anterior abdominal muscles in raising intra abdominal pressure during micturition, defecation, and parturition (child birth)
90
Where is endoabdominal fascia located?
between the parietal peritoneum and the muscles of the posterior abdominal wall
91
What does the iliac fascia cover?
encloses the psoas and iliacus muscles
92
what forms the medial arcuate ligament of the diaphragm?
the iliac fascia thickening (superiorly)
93
What does the iliac fascia fuse with/continuous with?
superiorly the iliac fascia fuses with the anterior layer of the thoracolumbar fascia;
iliac fascia is continuous with the transversalis fascia laterally
94
what does the thoracolumbar fascia enclose?
deep muscle of the back
95
where does the lumbar part of the thoracolumbar fascia extend?
between the 12th rib and the iliac crest
96
what does the thoracolumbar fascia attach to laterally?
the internal oblique an transversus abdominis
97
what lies between the anterior and middle layer of the thoracolumbar fascia (medially)
the quadratus lumborum
98
what lies between the middle and posterior layers of the thoracolumbar fascia (medially)
deep back muscles
99
what do the lumbar nerves exit the spinal cord through?
the intervertebral foramina, inferior to the corresponding vertebrae (then they divide into dorsal and ventral primary rami)
100
what do the lumbar posterior rami supply?
the muscles of the skin of the back
101
what do the lumbar ventral primary rami supply?
the psoas major muscle (connect with the sympathetic trunk)
102
Do the lumbar ventral rami receive rami communicantes? which communicantes?
all five receive gray rami from sympathetic trunk;
| L1 + L2 also send white rami communicates to the sympathetic trunk
103
what is the lumbar plexus formed by? where?
formed by the ventral rami of L1 - L4 within the psoas major muscle
104
What nerves are located lateral to the psoas major muscle? (superior to inferior)
1. Iliohypogastric (L1)
2. Ilioinguinal (L2)
3. Lateral Femoral Cutaneous (L2 + L3)
4. Femoral (L2 L3 L4)
105
From what lumbar nerve is the iliohypogastric nerve derived from
L1
106
where does the iliohypogastric nerve travel (course)
anterior to the fascia of the quadratus lumborum and near the anterior superior iliac spine, it pierces the transversus abdominis and divides into lateral/anterior branches
107
What does the lateral branch of the iliohypogastric nerve supply? course?
pierces through the internal and external oblique muscles and supplies the skin of the lateral side of the gluteal region
108
What does the medial branch of the iliohypogastric nerve supply? course?
runs BETWEEN the internal and external obliques and pierces the aponeurosis of the external oblique to supply the skin of the abdomen superior to the pubis (skin on top of the pubis)
109
From what lumbar nerve is the ilioinguinal nerve derived from
L2
110
where is the ilioinguinal located with respect to the iliohypogastric nerve?
located inferior to the iliohypogastric nerve
111
what is the course of the ilioinguinal nerve?
pierces the transversus abdominis, runs medially in the inguinal canal and exits through the superficial inguinal ring
112
what does the ilioinguinal nerve supply?
anterior side of the thigh and skin over the anterior scrotum and labia majora
113
From what lumbar nerve is the lateral femoral cutaneous nerve derived from?
L2 + L3
114
what is the course of the lateral femoral cutaneous nerve
runs obliquely on the iliacus muscle towards the anterior superior iliac spine and enters the thigh BELOW the inguinal ligament; then it is generally located between the sartorius and tensor fascia lata muscles;
divides into anterior and posterior branches
115
what does the lateral femoral cutaneous nerve supply?
anterior and lateral skin of the thigh
116
From what lumbar nerve is the femoral nerve derived from?
L2, L3 , L4
117
what is the course of the femoral nerve?
emerges from the psoas major muscle and descends inferiorly between psoas and iliacus and reaches the thigh POSTERIOR to the inguinal ligament
118
what is the function of the femoral nerve?
primary motor innervation to the iliacus and extensor muscles of the thigh;
sensory to the anterior and medial side of the thigh
119
what is the saphenous nerve?
terminal branch of the femoral nerve
120
what is the course of the saphenous nerve?
passes deep to the sartorius muscle while accompanying the femroal artery; runs with the great saphenous vein in the leg; in the distal part of the leg it divides into two terminal branches
121
what does the saphenous nerve supply?
sensory to skin of the anterior and medial side of the foot
122
what nerves located anterior to the psoas major?
Genitofemoral (L1, L2)
123
From what lumbar nerves is the genitofemoral nerve derived from?
ventral rami L1 + L2
124
what is the course of the genitofemoral nerve?
runs anterior to psoas major muscle and divides into the genital and femoral branches
125
what is the course of the genital nerve?
enters the inguinal canal through the deep ring
126
what is the function of the genital nerve?
motor to the cremasteric muscle (in males)
| sensory to anterior scrotum and anterior labia majora and adjacent parts of the thigh
127
what does the femoral branch of the genitofemoral nerve supply? course?
enters the femoral sheath and supplies the skin of the femoral triangle
128
what nerves are located medial to the psoas major?
1. obturator (L2 L3 L4)
| 2. Lumbosacral (L4,L5)
129
From what lumbar nerve is the obturator derived from?
L2, L3, L4 ventral rami
130
what is the course of the obturator nerve?
emerges from the medial side of the psoas at the inlet of the pelvis; runs inferiorly on the lateral wall of the pelvis (obturator internus) and enters the medial thigh through the obturator forament
131
what does the obturator nerve supply?
motor to all three adductor muscles (magnus, longus, brevis) and to gracilis
sensory to the skin of the medial side of the thigh and to the hip joint
132
from what lumbar nerves is the lumbosacral trunk derived?
inferior part of the ventral ramus of L4 + L5
133
what is the course of the lumbosacral trunk?
descends into the pelvis to help from the SACRAL plexus
134
does the lumbosacral trunk contribute to the lumbar plexus?
no
135
Where does the abdominal aorta start/end?
begins at the aortic hiatus at the intervertebral disc between T12/L2 and ends around L4 by dividing into two common iliacs
136
what does the abdominal aorta run adjacent to?
lies against the vertebral bodies
137
Where does the celiac trunk branch from the abdominal aorta?
At vertebral level T12; immediately inferior to the aortic hiatus
138
what does the celiac trunk supply?
abdominal foregut
139
where does the superior mesenteric artery branch from the abdominal aorta?
at the level of LV1; immediately inferior to the celiac trunk
140
what does the superior mesenteric artery supply?
the small intestine (jejunum + Ileum), and ascending and transverse parts of the colon
141
where does the inferior mesenteric artery branch off of the abdominal aorta?
at the level of L3; inferior to the renal arteries and from the left side of the aorta
142
what does the inferior mesenteric artery supply?
the descending colon, sigmoid colon and its terminal branch to the upper rectum
143
what is the terminal branch of the inferior mesenteric artery? what does it supply?
superior rectal artery, supplies the upper rectum
144
where do the middle suprarenal arteries arise? run? supply?
arise close to the origin of the superior mesenteric artery; run laterally to the suprarenal glands; supply supra renal glands
145
where are the renal arteries located? supply?
located inferior to the superior mesenteric artery; supply the kidneys
146
what is the course of the gonadal arteries? supply?
branches arise inferior to the renal arteries and run inferior on the psoas major muscle; the right artery passes over the IVC gives rise to testicular and ovarian arteries
147
what is the course of the testicular artery?
passes through the deep ring and enters the inguinal canal to become part of the spermatic cord
(Off of gonadal artery)
148
what is the course of the ovarian artery? supply?
from Gonadal artery; crosses the ends of the external iliac vessels to enter the pelvis where it supplies the ovary and uterine tube
**does not exit the abdominal cavity!
149
what vessels arise from the posteriolateral surface of the aorta?
inferior phrenic arteries and lumbar arteries
150
what is the course of the inferior phrenic arteries?
arise from the abdominal aorta just inferior to the diaphragm (lateral to the celiac trunk) ; pass superolaterally over the crura of the diaphragm
151
what do the inferior phrenic arteries supply?
the inferior surface of the diaphragm
152
How many lumbar arteries are there?
4
153
what is the course of the lumbar arteries? what do they supply?
Each pair passes around the sides of the four superior lumbar vertebrae and divides into anterior and posterior branches to supply the body wall
154
where does the median sacral artery arise? course?
arises from the posterior side of the aorta just proximal to its bifurcation and descends in the midline anterior to L4 and L5
155
Does the IVC have any valves?
Has a non-functional valve near its orifice
156
What is the IVC formed by? where?
union of the two common iliac veins anterior to L5 vertebrae, 2.5 cm to the RIGHT of the median plane and INFERIOR to the bifurcation of the aorta
157
what is the course of the IVC?
ascends on the right psoas major muscle, to the right of the aorta, and passes through the caval opening at the level of T8
158
where do lumbar veins drain into?
either IVC or ascending lumbar vein (vertical connecting vein)
159
where is the ascending lumbar vein located in the abdomen?
posterior to the psoas major muscle
160
where does the ascending lumbar vein enter the thorax?
enters the thorax posterior to the medial arcuate ligament
161
what does the left ascending lumbar vein join? right?
left ascending lumbar joins the LEFT SUBCOSTAL VEIN to form the HEMIAZYGOUS
right ascending lumbar joins the RIGHT SUBCOSTAL VEIN to form the AZYGOUS VEIN
162
how would the abdomen drain if the IVC were occluded?
blood can be channeled through the lumbar veins to the ascending lumbar veins to the azygous (or hemi then azygous) to the RA
163
what is the cisterna chyli?
a sac-like expansion at the inferior end of the thoracic duct (frequently absent); that receives lymph from lumbar lymph nodes and passes it to the thorax via the thoracic duct
164
where is the cisterna chyli located?
on the right side of the bodies of L1 and L2 vertebrae posterior to the right crus of the diaphragm
