Anatomy 4 - Obs and Gynae Surgical Incisions Flashcards
What are other names for suprapubic incision?
Bikini line
Pfannenstiel
What is the suprapubic incision used for?
Lower segment C-section
Abdominal hysterectomy
What method of cutting allows for better healing of skin?
Cutting along Langer lines
Or using relaxed skin tension lines
What is a relaxed skin tension line?
Parallel to dermal collagen bundles
Perpendicular to muscle contraction
WHat are the layers of the anterolateral abdominal wall?
Skin Superficial fasica Rectus sheath Anterior - Rectus abdominis Lateral - External oblique - Internal oblique - transverse abdominis
Describe the superficial fascia above the umbilicus
Single sheet of connective tissue
Describe the superficial fascia below the umbilicus
Superficial fatty layer (camper’s fascia)
Deep membranous layer (scarpa’s fascia)
What happens to the superficial fascia at the level of the perineum?
Scarpa’s fascia becomes Colles’ fascia
What is the deep fascia of the penis called?
Buck’s fascia
What are the flat muscles of the abdominal wall?
External oblique
Internal oblique
Transverse abdominis
What are the vertical muscles of the abdominal wall?
Rectus abdominis
Pyramidalis
(also sometimes the sternalis - not in everyone)
What is the largest and most superficial abdominal wall flat muscle?
External oblique
What direction do fibres run in external oblique?
Inferiomedially
Hands in pockets
What happens as the fibres of the external oblique approach the midline?
Form an aponeurosis - linea alba
What is an aponeurosis?
Broad flat tendon
Origin and insertion of external oblique?
Origin: ribs 5 - 12
Insertion: iliac crest, pubic tubercle and linea alba
What muscle is just deep to external oblique?
Internal oblique
What direction do fibres run in internal oblique?
Superiomedially
hands on chest
What happens as the fibres of the internal oblique approach the midline?
Form an aponeurosis - linea alba
What movements do internal oblique help with?
Twisting movements
Origin and insertion of internal oblique?
Origin: ribs 10 - 12
Insertion: thoracolumbar fascia, iliac crest and linea alba
What direction do fibres run in transverse abdominis?
Transversely
Origin and insertion of transverse abdominis?
Origin: lower ribs
Insertion: thoracolumbar fascia, iliac crest and linea alba
What divides the rectus abdominis into 3/4 smaller muscles?
Tendonus intersections
Why is the rectus abdominis broken up into smaller muscles?
Improve mechanical efficiency
What is main movement of rectus abdominis?
Flexion at trunk
What is formed at the lateral border of the two rectus abdominis muscles?
Linea semilunaris
Where does rectus abdominis stretch from and to?
From xiphoid process
To pubic symphysis
What is the pyramidalis?
Small triangular shaped muscle
What is deep to the pyramidalis?
Rectus abdominis
Where does pyramidalis stretch from>
Pubic bone
To linea alba
What is the function of the pyramidalis?
Tenses the linea alba
Where is the rectus sheath found?
Immediately deep to superficial fasica
What makes up the rectus sheath?
Combined aponeurosis of 3 flat muscles
What does the rectus sheath enclose?
Rectus abdominis
Why is the rectus sheath stitched closed after operations?
To increase strength of wound
Reduce risk of herniation
What makes up anterior wall of rectus sheath?
Aponeurosis of external obliques and half of internal oblique
What makes up posterior wall of rectus sheath?
Aponeurosis of half of internal oblique and the transverse abdominis
Where is the arcuate line found?
Third of way inferior between umbilicus and pubic bone
What happens to the aponeuroses at the arcuate line?
Here, all of the aponeuroses move to the anterior wall of the rectus sheath (i.e. there is no posterior wall)
Rectus abdominis is in direct contact with transversalis fascia
In what direction does the nerve supply to the anterolateral abdo wall enter?
From lateral direction
What do the 7th-11th intercostal nerves become?
Thoraco-abdominal nerves
What spinal nerve is the subcostal nerve?
T12 (anterior division of 12th thoracic nerve)
What spinal nerve is the iliohypogastric nerve?
L1 (superior branch of the anterior ramus of spinal nerve L1)
What spinal nerve is the ilioinguinal nerve?
L1 (inferior branch of the anterior ramus of spinal nerve L1)
Where do the nerves to the anterolateral abdo wall travel through?
Travel in plane between internal oblique and transverse abdominis
What arteries supply the anterior abdominal wall?
Superior epigastric arteries
Inferior epigastric arteries
What are the superior epigastric arteries a continuation of?
Internal thoracic (mammary) artery
What is anterior to the superior epigastric and inferior epigastric arteries?
Rectus abdominis
What artery foes inferior epigastric arteries branch from?
External iliac
What arteries supply the lateral abdominal wall?
Intercostal and subcostal arteries
What are the intercostal and subcostal arteries a continuation of?
Posterior intercostal arteries
How can you minimise injury to muscle when incising?
Incising in same direction as muscle fibre
What happens to the rectus muscles in lower segment C-section?
Not cut
Separated in opposite direction - moved towards nerve supply
Cut down linea alba
What layers are opened in lower segment C-section?
Skin and fascia Anterior rectus sheath Rectus abdominis Fascia and peritoneum Retract bladder Uterine wall Amniotic sac
What layers need to be stitched closed in lower segment C-section?
Uterine wall with visceral preitoneum
Rectus sheath
Fascial layer if large BMI
Skin
Why are lower segment C-sections better than large laparotomy?
Less risk of incisional hernias and dehiscence
What layers are opened in laparotomy?
Skin and fascia
Linea alba
Peritoneum
What layers are stitched closed in laparotomy?
Peritoneum and linea alba
Fascia if large BMI
Skin
What must be avoided if a lateral port is to be inserted via laparoscopy?
Inferior epigastric artery
Where does the inferior epigastric artery emerge?
Medial to deep inguinal ring
Where is the deep inguinal ring?
Midway between ASIS and pubic tubercle
In what direction does the inferior epigastric artery travel towards the rectus abdominis?
Superiomedial direction
What occurs at Hesselbach’s triangle?
Site of direct inguinal (i.e. into abdominal wall) hernia
Where is ureter in relation to uterine artery?
WATER UNDER BRIDGE
Ureter under/ inferior to artery