Week 4 - A - Anatomy 4 - O&G Surgical Incisions (LSCS, Laparotomy, Laparoscopy, Hysterectomy)

Question 1

What are the lines that relate to normal cell development in the skin known as? What are the lines that correspond to the natural orientation of collagen fibers in the dermis?

Answer 1

Blachko’s lines relate to normal cell development Langer’s lines correspond to the natural orientation of collagen fibres in the dermis

Question 2

When incising - for common surgical incision in obs and gynae - what lines do the surgeons use? (Common surgical incisions include, LSCS, laparotomy, laparoscopy, abdominal and vaginal hysterectomy) It will result in better healing and less scarring

Answer 2

Langers lines are used - run in the direction of collagen fibres Layers incised will vary depending on location of incision

Question 3

What is the most common location type of section for a cesarean section? This type of incision is also known as a Pfannenstiel section, give some other names for the insciions?

Answer 3

Lower segment casarean section Pfannenstiel incision - also known as a suprapubic incision or bikini-line incision

Question 4

The layers incised will vary depending on location of incision What are the layers of the anterior abdominal wall? What forms the rectus sheath layer?

Answer 4

Skin Superficial fascia Rectus sheath - formed by the aponeurosis from the external oblique, internal oblique and transversus abdominus Then the rectus abdominus

Question 5

The aponeurosis from the external oblique, internal oblique, transversus abdominus form the rectus sheath What is the midline fibrous band separating the rectus abdominus muscles formed from the apnoeurosis of these structures known as? What is its attachment points?

Answer 5

Midline fibrous band - linea alba Attaches from pubic symphysis to xiphoid process

Question 6

What direction do the external oblique fibres run in?

Answer 6

External oblique runs in the same direction as the external intercostals (hands in pockets direction)

Question 7

Anterolateral wall muscles All three attach to the lower ribs, iliac crests and linea alba What is the one other attachment of the different muscles?

Answer 7

External oblique - attaches to the lower ribs superiorly, lina alba medially, iliac crests inferiorly and pubic tubercle Internal oblique and transversus abdominus - attaches to the lower ribs, iliac crests, linea alba and the thoracolumbar fascia

Question 8

What does the external oblique muscles form with its attachment from what point on the iliac crests to the oubic tubercle? What is the relevance of the spinal umbilical line and external oblique muscle?

Answer 8

External oblique muscle aponouerois forms the inguinal ligament running from ASIS to the pubic tubercle The spinal umbilical line is the level at which the inferior end of the external oblique becomes aponeurotic - becomes aponueoritc meidally at the mid-clavicular line

Question 9

External obliqe, internal oblique and transversus abdominus all attach to lower ribs, iliac crests and linea alba What is the different thing they attach to?

Answer 9

External oblique- also attaches to the pubic tubercle Internal oblique and transversus abdominus - attaches to the thoracolumbar fascia

Question 10

What runs between the transversus abdominus and the internal oblique muscles?

Answer 10

The plane between the transversus abdominis and internal oblique is wehre the neurovascular bundles will runs (same as that in the thorax, the bundles run between the internal intercostals and the innermost intercostals)

Question 11

What is the curved tendinous intersection found on either side of the rectus abdominis muscle known as?

Answer 11

Curved tendinous intersection is known as the linea semilunaris

Question 12

Both the rectus abdominus and linea albea are wider at the top and narrow at the bottom (the rectus abdomins is also thinner at the top and chunkier at the bottom

The rectus abdominus is 3or4 paired smaller muscles

• What runs inbetween?

Answer 12

Tendinous intersections run inbetween the rectus abdominus muscles - linea albea is the tough fibrous layer in the midlines - linea semilunaris is the curved tendinous intersection running either side of the rectus abdominus

Question 13

What is the small triangular muscle, anterior to the rectus abdominis muscle, and contained in the rectus sheath? It attaches between the pubic crest and linea alba

Answer 13

This small triangular muscle is known as the pyramidalis muscle - present in 80% of people

Question 14

What is the fucntion of the pydramidalis muscle? What nerve supplies it?

Answer 14

Function of the muscle is to tense the linea alba - remember it attaches to the linea albea and pubic crest - it lies anterior to the rectus abdominus muscle enclosed within the rectus sheath Supplied by the subcostal nerve T12

Question 15

What is immediately deep to the superficial fascia? It is formed by the collective aponeurosis of the three anterolateral abdominal wall muscles

Answer 15

This is the rectus sheath

Question 16

This sheath almost completely encloses the rectus abdominus muscles The internal oblique aponeurosis splits into two and goes both anteriorly and posteriorly around the rectus abdominus When does the rectus sheath become only anterior to the rectus abdominus muscle?

Answer 16

This is at the level of the arcuate line - The arcuate line occurs about 1/2 of the distance from the umbilicus to the pubic crest

Question 17

At the level of the arcuate line, what happens to the aponeurosis of the anterolateral abdominal wall muscles?

Answer 17

These muscles aponeurosis run only anterior to the rectus abdominus

Question 18

When undertaking a suprapubic incision, which of the following layers/structures will be incised? OPTIONS: A - Both the anterior and posterior rectus sheath B - The anterior rectus sheath C - The external oblique muscle D - The posterior rectus sheath E - The transversus abdominis muscle

Answer 18

B - The anterior rectus sheath

Question 19

What are the nerve supply to the anterolateral abdominal wall? The nerves arise in the spine and curve round to supply the muscles and skin etc What muscles to the nerves travel within?

Answer 19

The 7th to 11th intercostal nerves T12 - subcostal nerve L1 - ilihypogastric and ilioinguinal nerve The muscles travel within the plane betweeen the internal oblique and transversus abdominus muscles

Question 20

The blood supply to the anterior abdominal wall comes from two main arteries, what are these? The blood supply to the lateral abdominal wall comes from the intercostal and subcostal arteries. What do they travel round to the abdominal wall between?

Answer 20

The superior and inferior epigastric arteries supply the anterior abdominal wall - they run posterior to the rectus abdominus The intercostal and subcostal arteries travel with the neurovascular bundles (with the nerves and veins) between the internal oblique and transversus abdominus muscles

Question 21

What does the superior epigastric artery come from? Where does the inferior epigastric artery come from? Where do they anatomose?

Answer 21

Superior epigastric artery is a direct continuation of the internal thoracic (mammary) artery Inferior epigastric artery is a branch of the external iliac artery

Question 22

When incising muscle for surgical incisions, it is good to incise in the same direction as the running muscle Why is this good that langers lines are followed then?

Answer 22

Langer’s lines are generally parallel to the orientation of the underlying muscle fibers Avoid damaging nerves especially motor nerves Avoid interrupting blood supply

Question 23

What muscle of the anterolateral abdominal wall is the exception for incising in a parallel direction?

Answer 23

The one exception is the rectus abominus muscle – can be cut transversely

Question 24

LSCS incision – aka suprapubic, bikin-line, pfannenstiel inscions LSCS incision is the most coomon type of caesarean session used * Does this incision cut, anterior, posterior or both rectus sheath? * Is the rectus abdominus muscle cut in a lower segment cesarean section?

Answer 24

Lower segment cesarean section cuts through the anterior rectus sheath - below the arcuate line The rectus abdominus is not cut in a LSCS - it is instead separated from each other in a lateral direction

Question 25

What are the layers to be opened during a LSCS?

Answer 25

• Skin - incised
• Superficial fascia - incised
• Rectus sheath anteriorly - incised
• Rectus abdominus muscle - pulled apart laterally
• Fascia and preitoneum - incised
• Retract bladder to visualise uterine wall
• Uterine wall - incised
• Amniotic sac - incised

Question 26

What are the layers which require stitching after a LCSC?

Answer 26

Uterine wall with visceral peritoneum Rectus sheath Skin

Question 27

A laparotomy is another type of surgical procedure involving a large midline incision through the abdominal wall to gain access into the abdominal cavity. What layers are cut through in a lapartomy? Which layers require stitching?

Answer 27

Skin Superfical fascia Linea alba Peritoneum Layers requiring stitchin - skin, linea alba, peritoneum

Question 28

In both laparotomy and LSCS, when is the superficial fascia stitched?

Answer 28

This is only stitched in patients with an increased BMI

Question 29

Although the midline incision is relatively bloodless (superior and inferior epigastric arteries are slightly lateral), what can this mean for wound healing?

Answer 29

can mean that healing is not as good increases the chance of wound complications e.g. dehiscence, incisional hernia Wound dehiscence is a surgical complication in which a wound ruptures along a surgical incision

Question 30

A laparotomy is a surgical procedure involving a large incision through the abdominal wall to gain access into the abdominal cavity. Laparoscopy is a type of surgical procedure that allows a surgeon to access the inside of the abdomen (tummy) and pelvis without having to make large incisions in the skin. This procedure is also known as keyhole surgery or minimally invasive surgery. Where are the incisions in laparoscopy?

Answer 30

Sub umbilical incision - may be all that is needed 2 lateral ports also Viewing pelvic organs position of uterus can be manipulated by grasping the cervix with forceps inserted through the vagina

Question 31

What must be carefully avoided for the lateral ports (incisions) in laparoscopy?

Answer 31

Must be careful to avoid the inferior epigastric arteries which run superomedially

Question 32

The inferior epigastric artery emerges just medial to the deep inguinal ring What is the inferior epigastric artery a branch of? What direction does the artery pass whilst posterior to what muscle? Where is the deep inguinal ling located?

Answer 32

The inferior epigastric artery is a branch of the external iliac artery The artery passes in a superomedial direction whilst posterior to the rectus abdominus muscles The deep inguinal ring is located halfway between the ASIS and the pubic tubercle

Question 33

What are the different types of hysterectomy? What are the methods of carrying out a hysterectomy?

Answer 33

Total hysterectomy - uterus and cervix Sub-total hysterecomty - just uterus Total hysterectomy with bilateral salpingo-oopherectomy - uterus, cervix, uterine tubes and ovaries Radical hysterectomy - uterus, cervix, uterine tubes, ovaries, part of vagina, lymph glands and fatty tissue Types - abdominal, laparascopic and vaginal hysterectomy

Question 34

What is often the incision used for an abdominal hysterectomy? What must be careful not to be damaged during the hysterectomy?

Answer 34

Often the LSCS is the type of incision used in an abdominal hysterectomy The ureter must not be incised during ligation of the uterine tubes

Question 35

During hysterectomy, extreme care must be taken to differentiate the ureter from the uterine artery Is the ureter anterior or posterior to the uterine artery? What happens when it is touched? What crosses theureters in men instead of the uterine arteries?

Answer 35

The ureter runs posterior to the uterine artery (water under the bridge) When touched it vermiculates -wiggles

In men, instead of the uterine arteries, the vas deferens crosses the ureter anteriorly