Abdomen Flashcards
Subcostal Incision
Following the curve of the ribs; incision avoids the internal thoracic artery & musculophrenic artery.
McBurney point
gives good access to the appendix
Gridiron Incision
Muscle splitting, from the belly button to the hip; Also where the McBurney point is made.
Suprapubic Incision (aka Pfannenstiel)
Is an incision used commonly for female surgeries (c-sections, etc.), also for males (hysterectomies, etc.)
Median Incisions
Gives greater access for complex surgeries. This incision used to be used for c-sections in the U.S.
Paramedian Incisions
used instead of median incisions if patient has a history of terrible adhesions
Camper’s layer
it is the most superficial fat layer in the abdominal wall right underneath the skin
Scarpas layer
Is located underneath the Camper’s layer; it extends and fuses with the fascia of deep thigh; it goes over the inguinal area & gonads as it turns to Darto’s and Colle’s fascia
Surgically, this layer will be closed off to prevent blood and urine from affecting abdominal wall/incision after a c-section/hysterectomy.
Endoabdominal fat
thin layer of fat underneath the deep abdominal muscles
Extraperitoneal fat
small layer of fat underneath the endoabdominal fat
Investing fascia
tightly adhered to the layers of the abdomen (external oblique, internal oblique, transverse oblique)
Transversalis Fascia
underlies the transverse abdominus muscle
Dartos Fascia
Technically, is Scarpa’s fascia but is called Dartos once it is over the gonads.
Serves to support and protect against blood and urine spreading
Colles’ Fascia
Technically is Scarpa’s/ Dartos fascia but is called Colles when it extends further below gonads. Purpose is to help support and protect against blood and urine spreading.
External Oblique m.
Most superficial abdominal muscle, its inferior portion will form the inguinal ligament (that connects ASIS-pubic tubercle); direction of muscle fibers is inferomedial
Internal Oblique m.
Underneath the external oblique muscle, fibers have a horizontal superior (kind of) direction,
Transverse Abdominal m.
Deepest layer of abdominal muscle, it is underneath the internal oblique m. Main function is to hold viscera in place which assists with the diaphragm in (expiration and inspiration); fibers are in horizontal directioin.
All Abdominal m.
ALL ab muscles help with maintaining posture, urinating, defecating, and child birth.
Pyramidalis muscle
Down the midline, right above gonad area. It is important for gynecology surgery because it is used to identify the midline especially in overweight people. This muscle is absent in 20% of people.
Linea semilunaris
straight lines down the midclavicular line that encloses the rectus sheath. (vertical ab lines)
Linea alba
down the midline where all the aponeurosis (flat sheet-like) unite. In thin people, you can see it above the umbilical button, but tends to fade below it.
Arcuate line
lower part to the posterior layer of the rectus sheath. It is where the inferior epigastric vessels perforate the rectus abdominis; beneath the arcuate line, all ab muscles will aponeurosis will run anterior to rectus abdominis muscles.
Falciform ligament
attaches to the liver
Urachus-Median Umbilical Fold
Connection between the fetal bladder and umbilicus; fetus can drain its bladder into this connection
Medial Umbilical Ligament
Houses umbilical arteries
Rectus Abdominus
primary vertical muscles in the middle. Each muscle is anchored by fibrous attachments called teninous intersection
Teninous Intersection
Fibrous attachments that anchor the rectus abdominus muscle. Mid lines between each rectus abdominus muscle.
Psoas Major
Originates from T12-L5; long, thick muscle located in the posterior abdominal wall and attaches (with iliacus muscle) to the lesser trochanter of femur; contributes to flexion and rotation of the hip
Psoas Minor
Originates from T12-L1; Stabilizes the hip joint.
Quadratus lumbordum
runs from rib 11 to the iliac crest; provides a lot of support and stability to the back
Iliacus Muscle
joins psoas at lesser trochanter of femur; helps to flex and externally rotate femur and also hip flexor
Thoracoabdominal nerves
Originates from T7-T11; Consist of the Anterior & Lateral cutaneous branches; runs between the interior and transverse abdominal muscles; provides motor, sensory, sympathetic fibers to anterior wall muscle, skin, hair follicles, & sweat glands.
L1 dermatone
consists of inguinal area
illioinguinal nerve
travels down the inguinal ligament, between the internal and transverse ab muscles; enters the inguinal canal midway, will emerge out of canal and innervates medial thigh; gonad area (penis/clitoral). This nerve plays important role in cremasteric reflex.
Genital branch of the genitofemoral nerve
Originates from L1-L2; enters the inguinal canal and travels all the way down to innervate the cremaster muscle IN the spermatic cord; stimulation of this nerve helps to elevate the testis in the scrotum to keep them from being overheated. Only in males
Cremaster muscle
extension of the internal oblique muscle; in the spermatic cord
Cremaster reflex
by lightly stroking the medial/inner part of the thigh, it will illicit a response for the testis to elevate; involves the genital branch of the genitofemoral nerve
Hesselbach’s Triangle
bordered by rectus abdominus muscle, inguinal ligament, and inferior epigastric vessels; area that is prone to direct hernias
What branches off femoral artery to supply abdominal wall?
Superficial epigastric artery, superficial circumflex iliac artery, external iliac artery, deep circumflex iliac artery, inferior epigastric artery
what supplies blood to the lateral and superior abdomen?
musculophrenic artery, superior epigastric artery, 10 & 11th posterior intercostal artery, subcostal artery
Abdomen main lymphatic drainage
Superficial inguinal lymph nodes and axillary lymph nodes
Abdomen venous drainage
mainly into the femoral vein, but also through internal thoracic vein, peri-umbilical vein, hepatic portal vein, thoracoepigastric vein, and superficial epigastric vein.
Inguinal canal
formed during embryonic development; in males: inside inguinal canal will be the spermatic cord; inside females inguinal canal will be the round ligament
Deep inguinal ring
passage into the inguinal canal; located lateral to the inferior epigastric artery; prone to indirect hernias
Superficial inguinal ring
exit of the inguinal canal; located superolateral to the pubic tubercle.
Medial and Lateral Crus
fibers that border the superficial inguinal ring.
Subinguinal Space
inferior to the inguinal ligament; this space is where the hip flexors and neurovascular structures serve the lower limb
Inguinal ligament
formed mostly by aponeurosis of external oblique but also a little bit of the fibers from transverse abdomen muscle
Gubernaculum
a fibrous tissue that is connected to the testes and ovaries and pulls them down to form the scrotum and labia majora. Will enter the deep inguinal ring and pass through the inguinal canal and out the superficial inguinal ring.
Processus Vaginalis
a pouch of peritoneal that is carried into the scrotum during the descent of the testes. Will then turn into the tunica vaginalis.
What are the layers of the spermatic cord?
- External spermatic fascia (originates from external oblique abdomen)
- Internal spermatic fascia (originates from transversalis fascia)
- Cremasteric muscle (originates from internal oblique abdomen)
- Processus vaginalis (originates from peritoneum)
Hernia
peritoneum protrudes out of the abdominal wall; happens when there is a weakening of the anterior abdominal wall. Can happen for a number of reasons (ex: surgeries, chronic cough, obesity, pregnancy, lifting, genetic, etc.)
Indirect Hernias
are congenital; Are the ones that most commonly occur (usually because lack of processus vaginalis closure)
Indirect=lateral to the inferior epigastric vessels; usually found within the inguinal canal (both deep ring and superficial ring)
Direct Hernias
will not pass through inguinal canal but rather will usually protrude in the hesselbach triangle region. Occurs medial to the inferior epigastric vessels.
What is the difference between omphalocele and gastroschisis?
Gastroschisis- intestines are outside of the abdomen (without sac) through hole in abdomen; usually related to disruption in bloody supply that prevents closures.; NOT related to chromosome abnormality
Omphalocele- intestines, liver, other organs are outside of the abdomen in a sac; can be caused by chromosomal abnormalities
