Ant. abdominal wall (3) anatomy pptsupdated

Ant. abdominal wall (3) anatomy pptsupdated

1. Anterior Abdominal Wall

2. Contents Borders Surface marking Layers – a) Skin b) Superficial fascia c) Deep fascia d) Muscles e) fascia Clinical aspect

3. Abdominal Wall The term of “Anterior Abdominal Wall” usually includes both the front as well as the side walls of the abdomen and needs to be called “Anterolateral Abdominal Wall”. The abdomen is the region of the trunk that lies between the diaphragm above and the inlet of the pelvis below.

4. Borders The border of anterior wall is defined superiorly by the xiphoid process of the manubrium sterni and the inferior aspects of the lower ribs that make up the subcostal margins. Caudally, the border is defined by the upper edge of the pubic symphysis, inguinal ligaments and the iliac crest.

5. Surface Marking

6. Layers – 1. SKIN it’s loosely attached to the underlying structures except at the umbilicus, there it’s tethered to scar tissue.The natural lines of cleavage in the skin are constant and run downward and forward almost horizontally around the trunk. Surgical incision – If possible all surgical incision should be made in lines of cleavage because of bundle of collagen fibers runs parallel rows.

7. b) Nerve supply The cutaneous nerve supply to anterior abdominal wall. It’s derived from ant. Rami of the lower six thoracic (T7 – T12) and L1 nerves. Thoracic nerves are lower 5 intercostal and subcostal nerves & 1 st lumber nerve is represented by iliohypogastric & ilioinguinal nerves. Dermatomes – T7 – Over the xiphoid process T10 – Includes the umbilicus. L1 – Above inguinal ligaments & pibic symphysis.

8. Nerve injuries Iliohypogastric or ilioinguinal nerve injury may be caused suture entrapment at the lateral folds of the transverse fascial incision, transection from incision, trocar placement during laproscopic surgery, thermal injury from electrosurgical devices or the formation of a neuroma during the normal healing process. Ilioinguinal nerve seems to be at greater risk than iliohypogastric nerve. Techniques to reduce the risk of nerve injury during laparotomy include the use of midline longitudinal incision as compared with a transverse incision. Avoiding the use cauterery on the perphorating branches of vessels help avoid to the terminal sensory nerve fibers, which typically run alongside these vessels.

9. c) Blood Supply Blood supply of the abdominal wall is comprised of superficial and deep vascular supplies. The superficial vasculature is located in the subcutaneous tissues and supplies the tissues superficial to the external oblique aponeurosis and anterior rectus sheath. The deep vasculature is located in the musculofascial layers. The superficial vessels composed – a ) superficial inferior epigastric artery. b) superficial circumflex iliac artery. c) superficial external pudendal artery. d) musculophrenic artery. The deep vessels composed – a ) superior deep epigastric artery. b ) inferior deep epigastric artery . c) deep circumflex artery.

10. Blood supply in skin of abdominal wall Skin of flank Branches of intercostal, lumber & deep circumflex iliac arteries. Skin near the midline Branches of superficial & inferior epigastric arteries. Skin of inguinal region Branches of superficial inferior epigastric , sup. circumflex iliac & sup. external pudendal arteries these are branches of FEMORAL ARTERY.

11. Blood Supply

12. d) Venus Drainage Above – Mainly into axillary vein via lateral thoracic vein. Below – Mainly into femoral via superficial epigastric & the great sephanous vein.

13. 2. Superficial fascia Divides into two parts – Fatty layer ( fascia of camper) Deep membranous layer (fascia scarpa ) Fatty layer – it’s continuous with superficial fat over the rest of the body and may be extremely thick (3 inc. or more thick in obese). It converts into dartose muscle into the scrotum.

14. Membranous layer – It’s thin and fades out laterally and above, where it becomes continuous with the superficial fascia of the back and thorax. Inferior membranous layer passes onto the front of thigh, where it fuses with deep fascia one finger breadth below the inguinal ligament. In the midline inferiorly membranous layer of fascia is not attached to the pubis but forms a tubular sheath for penis (or clitoris). Below in the perineum, it enters the wall of scrotum (or labia majora). From there it passes to be attached on each side of margins of pubic arch, it is there reffered to as COLLE’S FASCIA. Posteriorly it fuses with perineal body & post. margin of the perineal membrane.

15. 3. Deep Fascia It’s merely thin in the anterior abdominal wall deep of the membranous layer of the superficial fascia. It’s extention in the thigh is called FASCIA LATTA.

16. 4. Muscles Consist of 3 broad thin sheets are aponeurotic infront , 2 small muscles and 1 vertical muscle, they are :- 1) external oblique 2) internal oblique 3) transversus 4) rectus abdominis 5) pyramidalis 6) cremaster

17. External Oblique Muscle ORIGINE – Arises by eight flashy slips from the outer surface of middle of shaft of the lower eight ribs. The fibers runs downwards, forwards ,and medially. ISERTION – 1) Most of the fibers of the muscle end in a broad aponeurosis through which they are inserted from above to downwards into the xiphoid process, linea alba, pubic symphysis, pubic crest and the pectineal line of pubis. 2) The lower fibers of the muscle are inserted directly into the anterior 2/3 rd of outer lip of the iliac crest. NERVE SUPPLY – Lower six thoracic nerves.

18. Internal Oblique Muscle ORIGIN – Arises from;- the lateral 2/3 rd of inguinal ligament and the anterior 2/3 rd of the intermediate area of the iliac crest and the thoracolumbar fascia. From this origin, the fibres run upwards, forwards and medially crossing the fibres of the external oblique muscle at right angles. INSERTION – 1) the uppermost fibres are inserted directly into the lower three or four ribs and their cartilages. 2) the greater part of the muscle ends in an aponeurosis through which it is inserted into the 7 th , 8 th , 9 th costal cartilages, the xiphoid process, linea alba, pubic crest and the pectineal line of the pubis. NERVE SUPPLY – lower six thoracic nerves and the 1 st lumbar nerve.

19. Transversus Abdominis Muscle ORIGIN – the muscle has a fleshy origin from:- The lateral 1/3 rd of the inguinal ligament. The anterior 2/3 rd of the inner lip of the iliac crest. The thoracolumbar fascia. The inner surfaces of the lower six costal cartilages. The fibres are directed horizontally forwards. INSERTION – The fibres end in a broad aponeurosis which is inserted into the xiphoid process, linea alba, the pubic crest and the pectineal line of the pubis. The lowest fibres of the muscle fuse with the lowest fibres of the internal oblique to form the conjoint tendon . NERVE SUPPLY – Lower six thoracic nerves and 1 st lumbar nerve.

20. Rectus Abdominis ORIGIN – The muscle arises by two tendinous heads as follows. Lateral head from the lateral part of the pubic crest. Medial head from the medial part of pubic crest and ant. pubic ligament. The fibres runs vertically upwards. INSERTION - On the front of the wall of thorax, along a horizontal line passing laterally from the xiphoid process, and cutting in that order – 7 th , 6 th , and 5 th costal cartilages. NERVE SUPPLY – Lower six or seven thoracic nerves.

21. Pyramidalis ORIGIN – It’s arises from the anterior surface of the body of the pubis. INSRETION – It’s fibres pass upwards and medially to be inserted into the linea alba. NERVE SUPPLY – Supplied by subcostal nerve (T12). This is small triangular muscle. It’s rudimentary in human beings.

22. Cremaster muscle The cremaster muscle consist of muscle fasciculi embedded in the cremasteric fascia . The fasciculi form superficial loops from middle 1/3 rd of upper surface of inguinal ligament and the deep loops from pubic tubercle, pubic crest, and conjoint tendon. Here some fibres may be continuous with the internal oblique or transversus muscle. The medial end of the loops are attached to the pubic tubercle, the pubic crest or the conjoint tendon. This muscle is fully developed only in the MALE. NERVE SUPPLY – Genital branch of the genitofemoral nerve (L1). ACTION – The cremaster helps to suspend the testis and can elevate it. The muscle also tends to close the superficial inguinal ring when the intra abdominal pressure is raised.

23. Boundaries The anterior wall ;- Skin Superficial fascia External oblique aponeurosis The posterior wall ;- Fascia transversalis The extraperitoneal tissue The parietal peritoneum the conjoint tendon in it’s medial 2/3 rd Roof – It’s formed by the arched fibres of the internal oblique and transversus abdominis muscle. Floor – It’s formed by the grooved upper surface of the inguinal ligament and the medial end by the lacunar ligament.

24. 5. Fascia

25. Rectus sheath

26. Anatomical incisions Para median incision - It’s 2 to 5 cm Lateral to the mid plane. But now current scenario it’s not in much practice. Gridiron incision/ Rutherford Morision - it can be used to access the appendix predominantly for appendicectomy. It’s made at Mc Burney’s point ( 2/3 Lateral from the umbilicus to the ant. superior iliac spine). They involve passing through all the abdominal muscles. It’s oblique incision (superolateral to inferomedial). Lanz incision – It’s also used in appendicectomy at the Mc Burney’s point. It is an transverse incision. Due to it’s continuation with Langer’s lines the Lanz incision produces much more authentically pleasing results with reduce scarring.

27. Kocher incision – The kosher incision is subcostal incision Used to gain access for the Gallbladder biliary tree. The incision is made to run parallel to the  costal margin , starting below the xiphoid and  extending laterally . Classically it’s used for  open cholecystectomy . Two modifications and extensions of the Kocher incision are possible: - 1) Chevron / rooftop incision or modification - The extension of the incision to the other side of the abdomen.This may be used for oesophagectomy, gastrectomy, bilateral adrenalectomy, hepatic resections, or liver transplantation . 2) Mercedes Benz incision or modification - T he Chevron incision with a vertical incision and break through the xiphisternumThis may be used for the same indications as the Chevron incision, however classically seen in liver transplantation . all these subcoastal incisions provide the surgeon with  good exposure  to the abdominal viscera and tend to  heal well .

28. Midline incision - It is used for a  wide array  of abdominal surgery, as it allows the majority of the abdominal viscera to be accessed. A  midline laparotomy  can run anywhere from the xiphoid process to the pubic symphysis, passing around the umbilicus. The incision will cut through the skin, subcutaneous tissue, and fascia, the linea alba and tranversalis fascia, and the peritoneum before r eaching the abdominal cavity . this incision causes  minimal blood loss  or nerve damage, and can be used for  emergency procedures . Its positioning however does make it  susceptible to significant scars .

29. 6. Clinical Aspect C.A. of umbilicus - Ramnant of the vitellointestinal duct may form a tumour( raspberry or cherry red tumour). Faecal fistula, Meckel’s diverticulum and enter enterocoele. May umbilicus hernia seen if any weakness is present at umbilicus. C.A. of superficial fascia - Membranous layer of fascia of abdomen is continous with the superficial perineal pouch via scrotum and penis. At times, the urethra may rupture and urine extravasates into this space. Hernia - Hernia is a protrusion of any of the abdominal content through any of it’s wall. This is called external hernia. At times, the intestine or omentum protrudes into the ‘no entry’ zone within the abdominal cavity itself. The condition is called internal hernia.

30. THANK YOU