abdominal wall Flashcards
what structures can be found in the right upper quadrant
liver and gall bladder
what can be found in the left upper quadrant
jejunum
what can be found in the left lower quadrant
sigmoid colon
what can be found in the right lower quadrant
ileum, caecum and appendix
what lines divide the abdomen into quadrants
the transumbilical line at L3/4 and the median plane
what lines divide the abdomen into 9 regions
the midclavicular lines
the subcostal plane just below the costal margin at L3
the trans tubercular plane between the iliac crests at L4/5
what name is given to the top corners of the abdomen
left and right hypochondrium
what name is given to the top centre quadrant of the abdomen
epigastric region
what name is given to the centre of the abdomen
the umbilical region
what name is given to the centre sides of the abdomen
lumbar/ flank/ loin / lateral region
what name is given to the bottom left and right regions
groin/ inguinal region/ iliac fossa
what name is given to the bottom centre of the abdomen
pubic region/ supra pubic/ hypogastric
what is the superficial fatty layer of superficial fascia called
Camper’s fascia
what is the deep membranous layer of superficial fascia called
Scarpa’s
why is skin loosely attached to underlying structures
to allow movement and distension
if bruising is trapped under scarpa’s fascia what will be the appearance
blue swimming trunks anteriorly
what is camper’s fascia replaced by in the scrotum
dartos fascia
what is scarper’s fascia in the penis and scrotum known as
Buck’s and Colles’
it fuses with the fascia lata of the thigh and perineal body
where is the transversalis and extraperitoneal fascia
deep to the muscle layer
transversalis lines the inside of transversus abdominus
extra peritoneal fascia is between the transversalis fascia and the parietal peritoneum
where is the thoraco lumbar fascia
iliac crest to the 12th rib and is in 3 layers -ant, mid and post. they surround the back muscles and fuse together and give origin to transversus abdominis and internal oblique.
It is thicker and almost aponeurotic
what is the reason for lumbar hernias
external oblique is not attached to the thoracolumbar fascia
in what direction does external oblique go
downwards and medially
what are the functions of the abdominal muscles
supports abdom contents
raise intra abdo pressure
support vertebral column and create movement
respiration
which parts of the pelvis are on the same coronal plane
ASIS and pubic tubercle
what are the attachments of external oblique
lower 8 ribs, lateral lip of iliac crest, aponeurosis to linea alba via rectus sheath, forms inguinal ligament
there is a free edge posteriorly
what is the nerve supply to external oblique
T7-12
where is the inguinal ligament
ASIS to pubic tubercle
what does the inguinal ligament continue as
lacunar and pectineal ligaments
what is the superficial ring
triangular opening in external oblique aponeurosis with a base at the pubic crest
what are the attachments of internal oblique
thoraco lumbar fascia, iliac crest, lateral 2/3rds of inguinal ligament, lower 3/4 ribs and costal cartilages, aponeurosis to linea alba via rectus sheath, pubic crest behind the superficial inguinal ring via conjoint tendon
what is the nerve supply to internal oblique
T7 to 12 plus L1 via the iliohypogastric nerve to the fibres that form the conjoint tendon
what may predispose to inguinal hernias
injury to the iliohypogastric nerve which may weaken the conjoint tendon
what is the attachment of transversus abdominus
Attachments: thoracolumbar fascia; iliac crest (inside int obl); lateral 1/3rd or half of inguinal ligament; lower 6 ribs and costal cartilages; aponeurosis to linea alba (xiphoid to pubic symphysis) via rectus sheath; pubic crest behind the superficial inguinal ring via conjoint tendon (with internal oblique)
in what direction do the transvesus abdominis fibres pass
transversely
what is the nerve supply to trans. abdo
lower intercostal nerves (thoracoabdominal, nerve roots T7-T11), as well as the iliohypogastric nerve and the ilioinguinal nerve.
same as internal oblique
what makes up the conjoint tendon
formed from the aponeurosis of internal oblique and trans. abdom
what does the conjoint tendon attach to
the pubic crest and pectineal line behind the superficial inguinal ring, thereby supporting the ring
what are the attachments of rectus abdominis
costal cartilages ribs 5-7, xiphoid, pubic symphysis, pubic crest and pectineal line
what is the nerve supply of rectus abdominis
t7-12
where is pyramidalis
anterior to RA, from pubic crest to linea alba
which aponeurosis encloses RA
external oblique, int obl and trans abdom which form the rectus sheath
what is the linea alba
midline fusion of the rectus sheath
what happens at the arcuate line
all the aponeuroses pass anteriorly and the posterior sheath ends
demarcates the lower limit of the rectus sheath
the inferior epigastric vessels enter the sheath, behind rectus abdominis
Superior to the arcuate line, the internal oblique aponeurosis splits to envelop the rectus abdominis muscle.
Inferior to the arcuate line, the internal oblique and transversus abdominis aponeuroses merge and pass superficial (i.e. anteriorly) to the rectus muscle.
the arcuate line is well below the umbilicus
how long is the inguinal canal
4-6 cms
what does the inguinal canal contain
vas, testicular blood vesses, ilioinguinal nerve and genital branch of genitofemoral nerve
where is the superficial inguinal ring
in external oblique with its base on the pubic crest
it is supported from behind by the conjoint tendon
where is the deep inguinal ring
evagination of the transversalis fascia
overlain by internal and external oblique
Lies lateral to the inferior epigastric vessels, about 1 cm above the mid-point of the inguinal ligament – half way between the ASIS and the Pubic Tubercle
what does the deep inguinal ring transmit
vas and gonadal vessels
what is a hernia
a protrusion of a viscus through the wall of its containing cavity
may also be fat
where is an inguinal hernia found
above and medial to the pubic tubercle
where is a femoral hernia found
below and lateral to the pubic tubercle
it passes through the femoral canal
how might inguinal hernias present
a lump in the groin or testicle
describe the course of a direct inguinal hernia
through the posterior wall of the inguinal canal medial to the inferior epigastric vessels
usually a mature adult male
will pass through Hesselbach’s triangle
the viscera is covered by parietal peritoneum and pushes against a weakened conjoint tendon
will not be covered by spermatic fascia
describe the course of an indirect inguinal hernia
through the deep inguinal ring lateral to the inferior epigastric vessels
usually congenital or pre adolescent but can be any age
is within the spermatic cord
what are the boundaries of Hesselbach’s inguinal triangle
lateral: rectus abdominis muscle and inf epigastric vessels
inferior: inguinal ligament
what are the signs of a hernia
increases in size on coughing or straining
reduces in size when supine
may be painful if obstruction, also emesis and distension
strangulation: red and tender
what is the posterior abdominal wall made of
Quadratus lumborum
psoas major and minor overlying
iliacus
diaphragm superiorly
what is the function of QL
stabilises rib 12 for diaphragmatic movement in respiration and may weakly laterally flex the trunk
what is the insertion of iliopsoas
lesser trochanter
it is a hip flexor
where is the iliolumbar ligament
transverse process of L5 to the post sup iliac spine and iliac crest
what is the attachment of quadratus lumborum
iliac crest, iliolumbar ligament, L5 transverse process, 12th rib and L1 to L4 TPs
what is the nerve supply to quadratus lumborum
T12-L4
what is the attachment of psoas major
TP, bodies and IV discs of t12- L5
what is the nerve supply of psoas major
L1-3
what is the attachment of psoas minor
t12-L1 vertebral bodies to pectineal line and pectineal eminence on pelvic bone
what is the nerve supply of psoas minor
L1
what is the attachment of iliacus
iliac fossa
what is the nerve supply of iliacus
L2,3,4 via the femoral nerve
what does the femoral sheath surround
the femoral artery, vein and canal which transmits lymphatic and may be the site of a femoral hernia
the nerve is just outside the sheath
what is the femoral sheath made of
an extension of the abdominal transversalis fascia
what nodes does the femoral canal contain
Cloquet’s lymph nodes that receive directly from the glans
what is the medial boundary of the femoral canal
lacunar ligament
what is the proximal boundary of the femoral canal
femoral ring
what is the lateral boundary of the femoral canal
femoral vein
what is the posterior boundary of the femoral canal
pectineus or pectineal ligament
what is the anterior boundary of the femoral canal
inguinal ligament
what does the sup epigastric artery branch from
internal thoracic
describe the route of the sup epigastric artery
enters the upper part of the rectus sheath between the sternal and costal origins of the diaphragm
it descends behind the rectus muscle, supplying the upper central part of the anterior abdominal wall and anastomoses with the inferior epigastric artery
what artery supplies the upper lateral abdo wall
branches from the musculophrenic artery which is a branch of internal thoracic
what artery does inferior epigastric branch from
external iliac
describe the course of the inferior epigastric artery
it runs upwards and medially along the medial side of the deep inguinal ring and pierces the transversalis fascia to enter the rectus sheath anterior to the arcuate line
it ascends behind the rectus muscle, supplying the lower central part of the anterior abdominal wall, and anastomoses with the superior epigastric artery
what is the deep circumflex artery a branch of
external iliac just above the inguinal ligament
describe the course of the deep circumflex iliac
runs upwards and laterally towards the anterior iliac spine and then continues along the iliac crest
what does the deep circumflex iliac supply
lower lateral part of the abdominal wall
where are the superficial circumflex iliac and superficial epigastric arteries
they arise from the femoral just below the inguinal ligament
they supply the lower abdominal wall
what do the posterior intercostals and four lumbar arteries arise from
descending aorta
they pass forward between the muscle layers and supply the lateral part of the abdominal wall
where do the superficial circumflex iliac and superficial epigastric veins drain to
the proximal end of the great saphenous vein along with superficial and deep external pudendal veins
this is important in varicose surgery
in which direction do veins travel around the umbilicus (skin and fascia deep only)
they radiate away from it
they eventually drain into the femoral and external iliac inferiorly and axillary superiorly
how do para umbilical veins connect the system
they go to the portal veins of the liver forming a porto systemic anastomosis
what might result from obstruction of the portal vein
venous back pressure into the veins of the abdominal wall resulting in caput medusae
describe superficial lymph drainage of the anterior abdo wall
above umbilicus to the axillary nodes
below umbilicus to the superficial inguinal nodes
describe superficial lymph drainage of the posterior abdo wall
above the iliac crests to axillary nodes and below the iliac crests to the superficial inguinal nodes
which axillary nodes does the posterior superficial wall above iliac crests drain to
posterior or subscapular group
which axillary nodes does the anterior superficial wall above umbilicus drain to
anterior or pectoral group
where do axillary nodes empty into
subclavian lymph trunk
where is the T shaped superficial lymph node group
below the inguinal ligament and extending inferiorly along the great saphenous vein
what does the T group drain
anterior and posterior lower superficial abdo wall below umbilicus and iliac crest
where do the superficial nodes drain
deep inguinal nodes in the femoral canal which drain to external iliac and the para aortic nodes
where does deeper abdominal wall lymph drain
in parallel with epigastrics
inferiorly to the external iliac and then para aortic nodes
superiorly to the parasternal nodes alongside the thoracic artery and mediastinal nodes
what is the function of iliopsoas
pass to the lesser trochanter and are powerful hip flexors
what is the iliohypogastric nerve
originates from the lumbar plexus that supplies sensation to skin over the lateral gluteal region and motor to the internal and transverse abdominal muscles.
skin of L1 dermatome
L1
what is the ilioinguinal nerve
supplies internal oblique, spermatic cord, skin over penis and scrotum, skin covering mons pubis and labia majora
skin of L1 dermatome
L1
what nerves make up the lumbar plexus
iliohypogastric ilioinguinal genitofemoral lateral femoral cutaneous obturator femoral
plexus is in psoas major
what nerve is at risk if an incision is extended laterally during appendicecetomy
iliohypogastric
which arteries may form a collateral circulation in an obstructed aorta
inferior and superior epigastrics
is the deep inguinal ring medial or lateral to the inferior epigastrics
lateral
what is the nerve supply of the anterior abdominal wall
T7-12 and L1
