Anterior abdominal wall Flashcards
(33 cards)
What are the 9 regions of the abdomen?
- Left/right hypochondrium
- Epigastric
- Left/right lumbar
- Umbilical
- Left/right iliac fossa
- Suprapubic
What are the 2 longitudinal planes dividing the abdomen?
Mid-clavicular lines
What are the 2 transverse planes dividing the abdomen ?
- Subcostal plane (L2)
- Intertubercular plane (L4)
On slim individual, where does the umbilicus lie?
Opposite L3 vertebrae
What are the 2 layers of fascia overlying the anterior abdominal wall?
- Camper’s fascia (superficial): Fatty layer which is continuous with dartos fascia of scrotum in men.
- Scarpa’s fascia (deep): Membranous layer which is continuous with superficial perineal (Colles’) fascia.
What structures are located in the transpyloric plane?
Spinal:
- L1 vertebrae
- End of spinal cord
Vascular:
- Origin of the SMA
- Origin of hepatic portal vein
Visceral:
- Hila of the kidneys
- Pylorus of the stomach
- Neck of the pancreas
- Duodenojejunal flexure
- Fundus of gallbladder
Bony:
- Tip of 9th costal cartilage
Which muscles are found in the anterior abdominal wall?
- External oblique
- Internal oblique
- Transversus abdominis
- Rectus abdominis
What are the origins and insertions of external oblique?
Origin: Lower 8 ribs.
Insertions:
- ASIS and pubic tubercle (via inguinal ligament).
- Linea alba (forms anterior rectus sheath).
What is the innervation and function of the external oblique?
Innervation: (T7-12)
Functions:
- Compression of abdomen
- Flexion of trunk
- Bending of trunk
What are the origins and insertions of the internal oblique?
Origins:
- Thoracolumbar fascia
- Anterior 2/3 iliac crest
- Lateral 2/3 inguinal ligament
Insertions:
- Linea alba (via rectus sheath)
- Pubic crest
What is the innervation and function of the internal oblique?
Innervation:
- Lower 6 intercostal nerves (T7 – 12)
- L1 (ilioinguinal nerve)
Functions:
- Compression of abdomen
- Flexion of trunk
- Bending of trunk
What are the origins and insertions of the transversus abdominis?
Origins:
- Lower 6 costal cartilages
- Thoracolumbar fascia
- Anterior 2/3 iliac crest
- Lateral 1/2 inguinal ligament
Insertions:
- Linea alba (via posterior rectus sheath)
- Pubic crest (via conjoint tendon)
What is the innervation and function of the transversus abdomins?
Innervation:
- Lower 6 intercostal nerves (T7 – 12)
- L1 (ilioinguinal nerve)
Functions:
- Compression of the abdomen
What are the origins and insertions of the rectus abdominis?
Origins:
- Medial head (tendinous): Pubic symphysis
- Lateral head (muscular): Pubic crest
Insertions:
- 5th - 7th costal cartilages
What is the innervation and function of the rectus abdominis?
Innervation:
- T7-12
Functions:
- Compression of abdomen
- Flexion of vertebral column
- Accessory muscle of expiration
Which muscles form the conjoint tendon?
- Internal oblique
- Transversus abdominis
What is the roof and floor of the inguinal canal?
Roof: Conjoint tendon
Floor: Inguinal and lacunar ligament
What is the anterior and posterior walls of the inguinal canal?
Anterior:
- External oblique aponeurosis
- Inguinal ligament (at origin of internal oblique) Posterior:
- Medial: Conjoint tendon
- Lateral: Transversalis fascia
What is the roof and floor of the inguinal canal?
Roof: Conjoint tendon
Floor: Inguinal and lacunar ligament
What are the attachments of the inguinal ligament?
- Anterior superior iliac spine (ASIS)
- Pubic tubercle
What are the relations of the inguinal rings?
- Deep inguinal ring: Midline of the inguinal ligament
- Superficial inguinal ring: Medial to the inferior epigastric artery
What is the structure of the rectus sheath?
- In the upper abdomen, the aponeuronsis of the internal oblique divides into 2 layers, one anterior and one posterior to the rectus abdominis, forming rectus sheath.
- The aponeurosis of the external oblique fuses with the anterior layer.
- The aponeurosis of the internal oblique fuses with the posterior layer.
- 3-4 cm below umbilicus, aponeurosis of all 3 muscles become anterior to rectus abdominis.
- Free edge of the posterior rectus sheath is called the arcuate line.
What is the blood supply of the rectus abdominis?
- Superior epigastric artery
- Inferior epigastric artery (from external iliac artery and anastomoses with superior epigastric)
- Runs on posterior surface of rectus abdominis and anterior to posterior rectus sheath (above arcuate line)
- Runs medial to deep inguinal ring
What are the locationsof the 3 transverse tendinous intersections of the rectus abdominis?
- Xephisternum
- Between xephisternum and umbilicus
- At umbilicus
