GI , Snell Flashcards
Cutaneous supply to the anterior abdominal wall is derived from (2)
1) Anterior rami of lower six thoracic nerves (lower 5 intercostals and subcostal)
2) Anterior rami of first lumbar nerve
First lumbar nerve is represented by (2)
1) Iliohypogastric nerve
2) Ilioinguinal nerve
Dermatome of T7
Xiphoid process
Dermatome of T10
Umbilicus
Dermatome of L1
Just above the inguinal ligament and symphysis pubis
Arterial supply of abdominal skin: Midline
Superior and inferior epigastric
Arterial supply of abdominal skin: Flanks (3)
1) Intercostal
2) Lumbar
3) Deep circumflex iliac
Venous drainage of abdominal skin (2)
1) Axillary vein via lateral thoracic vein
2) Femoral vein via superficial epigastric and greater saphenous veins
Lymphatic drainage of abdominal skin: Above umbilicus
Anterior axillary LN
Lymphatic drainage of abdominal skin: Below umbilicus
Superficial inguinal LN
Superficial fascia of abdomen is divided into
1) Camper fascia (fatty)
2) Scarpa fascia (membranous)
Camper fascia is continuous with
Superficial fascia of the rest of the body
Scarpa fascia fades at
1) Lateral
2) Superior
Scarpa fascia continues inferiorly over the inguinal ligament to fuse with
Deep fascia of the thigh (fascia kata) ~1 finger breadth below the inguinal ligament
Scarpa fascia continues in the midline to form
A tubular sheath for the penis/clitoris
Scarpa fascia continues in the perineum to attach at the
Margins of the pubic arch to form the Colles’ fascia
Strongest layer of the anterior abdominal wall
Deep fascia
The cremaster muscle is derived from
Lower fibers of the internal oblique
The rectus sheath is formed by
Aponeurosis of the 3 lateral abdominal muscles
Arrangement of abdominal aponeurosis at the level of the ASIS
All 3 aponeuroses pass anteriorly to the rectus muscle, leaving the sheath deficient posteriorly
All 3 aponeuroses fuse with each other and with their fellows of the opposite side in the midline between the recti muscles to form the
Linea alba
Linea alba extends from
Xiphoid process above to symphysis pubis below
The transverse tendinous intersections that divide the rectus abdomens into segments are usually ___ in number
3
Abdominal tendinous intersections levels
1) Level of the xiphoid
2) Level of the umbilicus
3) Between the the xiphoid and umbilicus
Muscle fibers that form the conjoint tendon
Internal oblique and transversus abdominis
The lower free border of the internal oblique arches over the spermatic cord/round ligament of uterus, descends behind and attaches to
Pubic crest and pectineal line
Role of the conjoint tendon
Strengthens the medial half of the posterior wall of the inguinal canal
The inguinal ligament is formed by
Lower border of the aponeurosis of external oblique
Lower border of the inguinal ligament is attached to
Deep fascia of thigh (fascia lata)
The fascia transversalis lines the
Transversus abdominis
The fascia transversalis is continuous with (2)
1) Lining of the diaphragm
2) Lining of the iliacus
Fascia transversalis forms part of what sheath
Femoral sheath
Femoral sheath is formed by (2)
1) Fascia transversalis
2) Fascia iliaca
Content of inguinal canal in females
Round ligament
Content of inguinal canal in males
Spermatic cord
Inguinal canal leads to ___ in males
Testis
Inguinal canal leads to ___ in females
Labium majus
Inguinal canal: Length
4 cm
Inguinal canal: Extends from
Deep/internal inguinal ring laterally to superficial/external inguinal ring obliquely and medially
Inguinal canal: Lies parallel and immediately above the
Inguinal ligament
Deep inguinal ring: Oval opening in the
Fascia transversalis
Deep inguinal ring: Lies approximately ___ above the inguinal ligament
1.3 cm
Deep inguinal ring: Margins give attachment to
Internal spermatic fascia
Superficial inguinal ring: Shape
Triangular
Superficial inguinal ring: Aponeurosis of
External oblique
Superficial inguinal ring: Lies immediately above and medial to
Pubic tubercle
Superficial inguinal ring: Margins give attachment to
External spermatic fascia
Inguinal canal walls: Anterior
EOM aponeurosis
Inguinal canal walls: Posterior
Conjoint tendon medially, fascia transversalis laterally
Inguinal canal walls: Superior wall (roof)
IO and TA