Abdomen 1 Flashcards
Which abdominal organs are enclosed within the ribcage and pelvic bones?
Liver, pancreas and stomach
What is the abdominal wall?
A musculotendinous structure inferior to the costal margin, and superior to the ileum & pubic bones. Vertically, the abdominal wall traverses from the xiphisternum to the pubic symphysis.
What is the vertical boundaries of the abdominal wall?
Traverses from the xiphisternum to the pubic symphysis
What is the main function of the abdominal wall?
Encloses the abdominal cavity
Protects the abdominal viscera from injury, assist in forceful expiration by pushing the abdominal viscera upwards, involved in action that increases intra-abdominal pressure
What three functions increases intra-abdominal pressure?
Vomiting, coughing and defecation
What are the four main layers of the anterolateral abdominal wall? (Superficial to deep)
Skin
Superficial fascia
Muscles
Parietal peritoneum
What is superficial fascia above the umbilicus?
Connective tissue, single sheet
What two layers is the superficial fascia divided into below the umbilicus?
Superficial layer (Camper’s fascia)
Seep membranous fascia (Scarpa’s fascia)
Which layer of fascia contains the nerves and vessels (superficial epigastric veins) ?
Camper’s fascia
What are the three walls of the abdomen?
Anterior wall
Lateral wall
Posterior wall
Which structures are found within the anterior wall of the abdomen?
Rectus sheath
Rectus abdominis
Which muscles are located in the lateral wall of the abdomen (superficial to deep)?
External oblique
Internal oblique
Transversus abdominis
Which muscles form the posterior wall of the abdomen?
Psoas major Quadratus lumborum (Lateral to psoas major)
Which muscle lines the walls of the iliac bones?
Iliacus
Which deep fascia is the Fascia of Scarpa continuous with of the thigh below the inguinal ligament?
Fascia lata
Which fascia forms a sheath around the penis, and investment around the scrotum and superficial layer form fatty tissue of the mons pubic and labia major?
Fascia lata
What are the two main structures of the pelvis?
Anterior inferior iliac spine
Pubic tubercle
What are the three lateral flank muscle?
External oblique
Internal oblique
Transversus abdominis
How is the rectus sheath formed?
The flank muscles passes anteriorly and is replaced by aponeursosis, as the muscles continue towards the midline.
The aponeurosis intertwine forming the linea alba
What is formed from the midline of the aponeurosis of the flank muscles?
Linea alba
Where does the linea alba extend from?
From the diploid process to the pubic symphysis
What is the origin of the external oblique?
Outer surface of the lower 8 ribs (5 to 12)
Where does the external oblique insert?
Inserts into lateral lip of the iliac crest and public tubercle
What forms the free inferiorr border of the external oblique?
Anterior half of the iliac crest forming the inferior border, the lower border forms the inguinal ligament
The lower border of which flank muscle forms the inguinal ligament?
External oblique
The deficiency within which flank muscles forms the external opening of the inguinal ring?
External oblique
How is the superficial inguinal ring formed?
A deficiency within the inguinal ligament formed from the external oblique (external opening)
What is the function of the external oblique?
Compresses abdominal contents, flexion o the trunk and rotates the torso.
Guards viscera, contained within the abdominal and pelvic cavities
Raises intra-abdominal pressure in expulsion and exhalation.
what is the orientation of the external oblique muscles?
Inferomedial deep to the superficial fascia
Which muscle is deep to the external oblique?
Internal oblique
Which direction to the internal oblique fibres pass?
Superomedial direction
Where does the internal oblique originate from?
Originates from the lateral 1/3 of inguinal ligament, and anterior 2/3 of the iliac crest
Thoracolumbar fascia
Where does the internal oblique insert into?
Insert into the lower costal cartilages (7 to 12)
What forms medially of the internal oblique?
Aponeurosis forms linea alba, participating in the formation of the rectus sheath
What is the inferior border of the internal oblique?
The conjoint tendon of the iliopectinal line, pubic and ileum
What is the main function of the internal oblique?
Bilateral contraction compresses the abdomen, whereas unilateral contraction ipsilateral rotates the trunk.
Which muscle is deep to the internal oblique?
Transversus abdominis
In which direction do the fibres of the Transversus abdominis muscle orientate?
Transverse direction
What are the lateral attachments of the Transversus abdominis?
Continues line from lower 6 costal cartilages (7 to 12)
Thoracolumbar fascia, iliac crest, and lateral 1/3 of the inguinal ligament
What are the medial attachments of the Transversus abdominis?
Aponeurosis towards midline, forming the rectus sheath.
Most inferior fibres form the conjoint tendon of the aponeurosis of the internal oblique
Which two flank muscles form the conjoint tendon?
Internal oblique
Transversus abdominis
What is the function of the Transversus abdominis?
Compresses the abdominal connotes
Raises intrabdominal pressure
Which direction do the inferior internal oblique orientate themselves into?
Arches downwards towards the pubic, important for the inguinal canal
Which fascia covers each of the posterior and anterior surfaces of the flank muscles?
Transversals fascia
Which is the main muscle of the anterior abdominal wall?
Rectus abdominis
How is the rectus abdominis split from the midline?
The linea alba
What are the lateral borders of the rectus abdominis?
Linea semilunaris
What are the superior attachments of the rectus abdominis?
5-7 costal cartilages (laterally)
How many pairs of compartments are formed by the rectus abdominis?
Four
How are the rectus abdominis compartments separated?
Tendinous intersections
What types of contractions are initiated by the tendinous intersections of the rectus abdominis?
Segmental contraction
What forms the inferior attachments of the rectus abdominis?
Pubic crest
Pubic symphysis
What encloses the rectus sheath?
The aponeurosis of the internal/external oblique and transverses abdominis
What is the function of the rectus abdominis?
Assisting the flank muscles in compressing the abdominal viscera, the rectus abdominis stabilises the pelvis during walking and depresses the ribs.
Which muscle helps to stabilise the pelvis during walking?
Rectus abdominis
Which direction does the external oblique aponeurosis pass?
Passes anterior to the rectus sheath
Which direction does the internal oblique aponeurosis pass around the rectus abdominis?
Splits posterior and anterior
Which direction does the transverses abdominis aponeurosis pass the rectus abdominis?
Posterior direction
Which fascia is covers the flank muscles?
Flank muscles are covered by transversalis fascia which converge together
What is the arcuate line?
At the point midway between the umbilicus and the pubic symphysis
Which is found at a point midway between the umbilicus and the pubic symphysis?
The arcuate line
Which part of the rectus abdominis do the aponeuroses of the flank muscles move anterior to the rectus muscle?
Lower one quarter of the rectus abdominis
What happens to the flank muscles at the arcuate line?
Aponeuroses move anterior to the rectus muscle, there is no posterior wall of the rectus sheath, and the anterior wall of the sheath consist of aponeuroses of flank muscles
From which point, inferiorly, is the abdominis muscle in direct contact with the transversals fascia?
Arcuate line
Which muscle is positioned superficially to the psoas major?
Quadratus lumborum
Where does the quadratus lumburum originate?
Posterior iliac crest and the iliolumbar ligament
Where does the quadratus lumborum insert into?
Inserts into the transverse process of L1-L4 and the inferior border of the 12th rib.
In which direction to dh fibres of the quadratus lumborum travel?
Supermedially
What is the main function of the quadratus lumborum?
Extension an lateral flexion of the vertebral column
Stabiliser of the 12th rib during inspiration, preserving the contraction of the diaphragm
What is the relation of the psoas major and the posterior abdominal wall?
Resides beside the midline of the posterior abdominal wall, immediately alter to the lumbar vertebrae
What is the origin of the psoas major?
Transverse processes and vertebral bodies of T12 and l5
Where does the psoas major insert?
Moves inferiorly and laterally, running deep to the inguinal ligament and attaching to the lesser trochanter
What is the function of the psoas major?
Flexion of the thigh at the hip, and lateral flexion of the vertebral column, depending on which extremity is fixed in position.
Which two muscles form the combined tendon that inserts into the lesser trochanter of the femur?
Iliacus
psoas major
Which combined tendon is formed between the iliacus and psoas major?
Iliopsoas
Where does the iliospsoas insert into?
Inserts to the lesser trochanter of the femur
What is the iliacus?
The ilacus is a fan shaped muscle that is situated inferiorly on the posterior abdominal wall, combines with the psoas major. Major flexor of the thigh, lines the interior surface of the ileac wing.
Which two flank muscles form sheaths around the quadratus lumborum?
Internal oblique + Transversus abdominis form sheaths around the quadratus lumborum
What is the psoas minor?
The psoas minor muscle is present within 60% of the population, resides anterior to the psoas major. Originates from the vertebral bodies T12 & L2, attaches to a ridge on the superior ramus of the pubic bone Pectineal line; flexion of the vertebral column.
Which are the two main arteries of the abdominal walls?
Segmental arteries
Longitudinal arteries
What are the segmental arteries?
Segmental arteries (Axial plane): Intercostals 7-11; subcostal artery & lumbar arteries.
What are the longitudinal arteries?
Superior epigastric artery
Inferior epigastric artery
What does the superior epigastric artery arise from?
internal thoracic artery
Which artery does the superior epigastric anastomose with?
Ascending artery, the inferior epigastric artery
Which artery does the inferior epigastric artery arise from?
External iliac artery
What is the venous drainage of the abdominal wall?
Segmental veins, subcostal and the 1st and 2nd lumbar veins to form th ascending lumbar veins
azygous system
Which vein does the 3rd and fourth lumbar vein drain into?
Inferior vena cava
Which vein is superior to the umbilicus?
Anterior longitudinal vein s
Which vein does the epigastric vein drain into?
Internal thoracic vein
Which vein does the inferior epigastric vein drain into?
External iliac vein
What are the main spinal abdominal nerves?
T7-L1
Where do the neuromuscular bundles reside between?
Between the transverses abdominis, and the internal oblique
Which nerve supplies the epigastrium?
T7
Which nerve supplies the umbilicus?
T10
Which nerve supplies the inguinal ligament?
L1
Which nerves arise from the genitofermoal nerve`?
Genital branch and the short femoral branch
Which nerve is associated with t12?
Subcostal nerve
Which 2 nerves are associated with l1?
Ilioinguinal nerves
iliohypogastric nerves
what is the relationship of the inferior epigastric vessels?
Drain raise from the external iliac vessels,s
Describe the path to which the inferior epigastric vessels pass?
Pass medially to enter into the rectus sheath, the inferior regions are narrower in comparison to the superior regions
This exhibits a weakness. between the inferior epigastric and rectus sheath; lowest part of the aponeuroses of the anterolateral abdominal wall
Which nodes does the lymph above the umbilicus drain into?
Axillary nodes
Which nodes do the lymph below the umbilicus drain into?
Inguinal nodes
Which nods form a chain immediately inferior to the inguinal ligament?
Superficial inguinal lymph nodes
Where does the inguinal pass?
Extends inferiorly and medially through the inferior part of the abdominal wall
Which structure is transmitted by the inguinal canal in males?
spermatic cord
Which structure is transmitted by the inguinal canal in females?
Round ligament of the uterus
Where does the spermatic cord pass into?
Into the scrotum
Where does the round ligament pass towards?
The labium majora
What reinforces the posterior wall?
Transversalis fascia reinforced medially by conjoint tendon (Of internal oblique & transversus abdominis)
What forms the floor of the inguinal ligament?
Inguinal ligament, thickened medially by the lacunar ligament, and the most inferior part of the external oblique aponeurosis Bends posteroinferiorly to form a gutter appearance of surface of inguinal ligament, and medial pectineal region.
What forms the roof of the inguinal canaL?
Transversalis fascia, internal oblique & transversus abdominis. The roof is formed by the arching fibres of the internal oblique, these fibres initiate laterally anterior to the canal, pass over to form the roof; medially joining with the aponeuroses of the transversus abdominis to form the conjoint tendon.
What is the deep inguinal ring?
Abdominal entrance to the canal (transversalis muscle) is known as the deep inguinal ring.
what is an indirect hernia?
The peritoneal sac enters the inguinal canal through the deep inguinal ring
What is the direct hernia?
The peritoneal sac enters the inguinal through the posterior wall of the inguinal canal.
Which vessels lie medially to the deep inguinal ring?
The external iliac vessels
