Abdomen Flashcards
Abdominal surface anatomy: demonstrate the bony and cartilaginous landmarks of the abdomen and surface projections of the abdominal organs, demonstrate the descriptive regions of the abdomen Abdominal wall: describe the anatomy, innervation and functions of the muscles of the anterior, lateral and posterior abdominal walls. Explain their functional relationship with thoracic and pelvic diaphragms, and their roles in posture, ventilation and voiding of abdominal/pelvic/thoracic contents Inguina
What is the anatomy of the pelvic girdle? What are the three main parts that make it up?
Made up of the pelvis, sacrum and coccyx. Iliac crest, iliac fossa, anterior superior iliac spine (ASIS). Pubic symphysis, pubic tubercle, superior pubic ramus.
How is the abdominopelvic cavity defined?
Shown in pink (abdominal cavity) and green (pelvic cavity). Abdominal cavity partly overlaps into the thoracic region. Pelvic cavity is backwards and downwards. Abdominal and thoracic cavity separated by the diaphragm. The pelvic inlet (pelvic brim) arbitrarily separates the abdominal from the pelvic cavity, though the abdominal and pelvic cavities are both CONTINUOUS.
What is the pelvic brim?
Photo
What visceral structures are found in the abdomen?
Stomach, duodenum, small and large intestines. Liver, pancreas, spleen. Kidneys, ureters and urinary bladder. Reproductive organs. Abdominal vessels.
What are the 9 regions of the anterior abdominal wall?
Photo.
What is the alternative name for iliac region?
Groin region.
What is the alternative name for lumbar region?
Flank region.
What are the 4 regions of the anterior abdominal wall?
Right upper quadrant, left upper quadrant, left lower quadrant, right lower quadrant.
How is the anterior abdominal wall divided into four regions?
Midline through the sagittal plane. Horizontal line called the trans-umbilical plane which runs through the umbilicus.
What organs are found in each of the four abdominal quadrants? (x2 for each)
RIGHT UPPER: liver and gallbladder. LEFT UPPER: stomach and spleen. RIGHT LOWER: cecum and appendix. LEFT LOWER: end of the descending colon and sigmoid colon.
What is the surface anatomy of the appendix?
The McBurney’s point which is 1/3rd of the way along a line from the right anterior superior iliac spine to the umbilicus.
What are the posterior abdominal wall muscles? (x6) Functions of the two major muscle groups?
PSOAS MAJOR: attachments to the bodies and discs of the lumbar vertebrae and lesser trochanter of femur (they are the FLEXORS of the hip and trunk). ILIAC MUSCLE: found inferior to the iliac crest. QUADRATUS LUMBORUM: attachments to the lower border of the 12th rib and transverse process of the 5th lumbar vertebrae and adjacent iliac crest. Stabilises the 12th rib and a lateral flexor of the trunk. TRANSVERSE ABDOMINUS. DIAPHRAGM. AND…ERECTOR SPINAE MUSCLES: found posteriorly to the vertebral column.
Lateral layers: Three flat-sheet muscles.
External obliques. Internal obliques. Transversus abdominus (or innermost). All separated by their own fascia. Contribute to the recuts sheath.
What are the functions of the three flank sheet muscles? (x3)
This describes the obliques and transversus abdominus. 1. Compress the abdomen and increase the intra-abdominal pressure to aid expiration (most important muscles in forces expiration), and evacuation of urine, faeces, parturition (childbirth) and heavy lifting. 2. Supports the viscera – “guarding” mainly the intestines. 3. Flex and rotate the trunk.
What are the attachments of the external obliques?
Attached to: (1) external surface of lower 8 ribs; (2) free posterior border (no attachments at all); (3) fans out to attach to xiphoid process, linea alba, pubic crest and tubercle, anterior half of iliac crest.
What is the aponeurosis?
A sheet of pearly white fibrous tissue that acts as a tendon, having a wide area of attachment. What is the anatomy of the aponeurosis? (x2 points) Fuses medially with the rectus sheath. Fusion of the aponeurosis in the midline forms the linea alba. Lower aponeurotic edge is rolled inwards and forms the inguinal ligament (from ASIS to pubic tubercle).
What is the rectus sheath?
A fascia formed by the aponeuroses of the transverse abdominal and the external and internal oblique muscles. Form in the middle to create the linea alba.
How does the rectus sheath differ above and below the umbilicus?
ABOVE: internal oblique aponeurosis split and encloses the rectus abdominus (pink). The aponeurosis of external oblique (green) is in front and the transversus (blue) behind the rectus muscle. BELOW: all three aponeurosis layers are interior to the recuts muscle.
What are the attachments of the internal obliques?
LATERALLY, there are attachments to the thoracolumbar fascia (connective tissue associated with posterior muscles), iliac crest (anterior 2/3rds) and the inguinal ligament (lateral half). MEDIALLY, there are attachments to the lower 3 ribs and costal cartilages, xiphoid process, rectus sheath and conjoint tendon.
What is the conjoint tendon?
Lowest fibres of the internal oblique aponeurosis and similar fibres of the transversus abdominis aponeurosis join to form the conjoint tendon. Conjoint tendon attached medially to linea alba.
What are the attachments of the transversus abdominus?
LATERALLY, there are attachments to the lower 6 costal cartilages, thoracolumbar fascia, iliac crest (anterior 2/3rd), inguinal ligament (lateral 1/3rd). MEDIALLY, there are attachments to the xiphoid process, linea alba (rectus sheath), symphysis pubis, conjoint tendon.
Where does the neurovascular plane lie in relation to the three flank muscles?
Lies between the internal and transversus abdominis muscle layers.
What directions to each of the three flanks point?
External obliques: downwards and forwards. Internal obliques: downwards and backwards. Transversus abdominus: directly horizontal.
What are the attachments and relative positions of the rectus abdominus muscles?
Long strap muscle of the anterior abdominal wall enclosed in rectus sheath. SUPERIOR ATTACHMENTS: 5-7 costal cartilages and the xiphoid process. INFERIOR ATTACHMENTS: symphysis pubis and the pubic crest. How is the rectus abdominus divided? Divided into segments by tendinous intersections (3 pairs – one on each side of the linea alba) which are attached to the anterior wall of the rectus sheath.
What are semilunar lines? Surface anatomy?
Called linea semilunaris: curved tendinous intersection found on either side of the rectus abdominis muscle. Each corresponds with the lateral border of the rectus abdominis. It extends from the cartilage of the ninth rib to the pubic tubercle, and is formed by the aponeurosis of the internal oblique.
What is the epigastric fossa?
Slight depression in the midline just below the sternum (where a blow can affect the solar plexus).
What is the blood supply of the rectus muscle? (x2) Branches of what?
SUPERIOR EPIGASTRIC ARTERY – terminal branch of internal thoracic artery. INFERIOR EPIGASTRIC ARTERY – branch of external iliac artery. These two arteries enter the rectus sheath and anastomose, forming a potential by-pass to abdominal aorta.
What is the internal iliac artery?
Branch of the external iliac artery and supplies tissues in the pelvic region.
What is the blood supply of the flank muscles? (x4)
Intercostal arteries 7-11. Subcostal artery. Lumbar arteries. Deep circumflex iliac arteries.
What regions of the dermatome are sensory to each of the 9 regions of the anterior abdominal wall?
Epigastric row = T7. Umbilicus region = T10. Inguinal region = T12 (inguinal ligament = L1).
What is the somatic sensory supply of the parietal peritoneum and the visceral peritoneum?
PARIETAL: same segmental nerves of the body wall. VISCERAL: has NO somatic sensory innervation.
What are the motor nerve supply for the external obliques, internal obliques, transversus abdominus and the recuts abdominus?
EXTERNAL: T7-T11. INTERAL OBLIQUE AND TRANSVERSUS: T7-T12 and L1. RECTUS: T7-T12 (no L1).
What nerves supply the antero-lateral abdominal wall? (x3)
Subcostal nerve (T12), ilio-hypogastric and ilioinguinal nerves (L1).
What are the motor nerves that supply the quadratus lumborum, psoas major and iliacus?
Quadratus lumborum: T12-L4. Psoas: L2-L4. Iliacus: femoral nerves L2-L4. The lumbar plexuses are mainly for the LOWER LIMBS.
What is the transumbilical plane?
The horizontal plane that separates the abdominal wall above and below the umbilicus.
How is the superficial tissue of the abdomen lymphatically drained? Above and below the transumbilical plane?
Superficial lymphatics accompany subcutaneous veins. Lymphatic drainage happens in QUADRANTS.
ABOVE PLANE: to the pectoral group of axillary nodes. BELOW PLANE: to the superficial inguinal nodes.
How is the deeper abdominal tissue lymphatically drained? Above and below the transumbilical plane?
Deep lymphatics accompany deep veins in the extraperitoneal tissues. ABOVE PLANE: to the mediastinal nodes (found in mediastinum). BELOW PLANE: to the external iliac and para-aortic nodes (describes the associated veins).
What does the inguinal area describe? Anatomical landmarks that outline it?
The groin. The junction between the anterior abdominal wall and the thigh. Area is between the ASIS and the pubic tubercle.
What is the nature of the strength of the anterior abdominal wall in the inguinal region? Clinical AND anatomical importance?
Wall is WEAKENED in the inguinal region. CLINICAL IMPORTANCE: potential site of abdominal hernias. ANATOMICAL IMPORTANCE: structures exit and enter the abdominal cavity here e.g. spermatic cord, round ligament, vessels.
Hernia in the inguinal region is more common in which sex?
Males.
What is the anatomy of the inguinal region?
Pay attention only to the big labels.
What is the inguinal ligament made from?
Rolled inferior edge of the external oblique aponeurosis – between ASIS and pubic tubercle.
What is the anatomy of the inguinal CANAL?
Inguinal canal lies above the inguinal ligament and extends FROM deep inguinal ring (found in transversalis facia) to superficial inguinal ring (a hole in the external oblique aponeurosis, above and medial to the pubic tubercle).
What are the walls of the inguinal canal?
Not sure I need to concentrate on learning this. Seems quite obvious and bit unnecessary.
What are the two areas of particular weakness in the inguinal region?
INGUINAL CANAL and FEMORAL CANAL.
What passes through the inguinal and femoral canal? (for Inguinal, x2 for males, x1 for females, x1 for both sexes). (for Femoral, x2).
INGUINAL: testis and spermatic cord descend into the scrotum. In females, the uterine round ligament descends through the developing inguinal canal. Inguinal nerve passes through also, in both sexes. FEMORAL: below the inguinal ligament – femoral artery and vein passes.
What is a hernia?
Part or whole of an organ or tissue abnormally protrudes through the wall of the structure containing the organ or tissue.
What is the anatomy of a hernia in the abdomen?
Hernial sac is made from the skin on the outside, abdominal wall and more internally, the peritoneum.
What are the signs of hernia? (x4) – very general.
- Lump or protrusion of groin. 2. Painless/painful and uncomfortable. 3. May be reducible or irreducible. 4. May be strangulated with tissue death and associated with vomiting, constipation, intestinal obstruction (this is an emergency situation).
What – out of inguinal or femoral hernias – are most common?
Inguinal.
What are the two types of inguinal hernia?
Indirect and direct.
Out of direct and indirect inguinal hernia, which is most common?
Indirect.
What are direct and indirect inguinal hernias?
DIRECT: defects go through Hesselbach’s Triangle (inguinal triangle), which is always MEDIAL to the inferior epigastric vessels, pushing through peritoneum and transversalis fascia of the POSTERIOR WALL of the inguinal canal.
INDIRECT: defects go through the internal (aka deep) ring which is LATERAL to the inferior epigastric vessels i.e. indirect path through the abdominal wall. Once it enters the deep ring, it passes through the inguinal canal, external inguinal ring and into the scrotum.
What are the causes of direct inguinal hernia? (x3)
- Older age. 2. Chronic straining. 3. Weak musculature.
What are the causes of indirect inguinal hernia? (x1)
Tends to be in younger adults and children.
Epidemiology of femoral hernias? (x2 points)
More common in elderly and females.
What are the borders of the femoral canal?
SUPERIOR: inguinal ligament. INFERIOR: pectineus fascia. MEDIAL: lacunar ligament. LATERAL: femoral vein.
What are the signs of femoral hernia? (x3)
Irreducible, hot and painful.
How can inguinal and femoral hernias be differentiated?
Femoral hernias appear BELOW and LATERAL to the pubic tubercle. Inguinal hernias appear ABOVE and MEDIAL to the pubic tubercle.
What are the two causes of hernia?
CONGENITAL and ACQUIRED.
What is a congenital hernia?
The descent of the testes requires the processus vaginalis, which is a finger-like projection of parietal peritoneum. This fetal structure normally closes, however, a persistently patent (open) processus vaginalis is a ready-made indirect inguinal hernial sac.
What is an acquired hernia? (x1 and x3 causes)
Any cause of increased intra-abdominal pressure can be exploit a weak abdominal wall, whether the weakness is purely due to the inguinal canal or because there is weakening of tissue with age, fatty infiltration associated with obesity, or the increase in circulating elastases that have weaken abdominal musculature.
What are the two types of hernial treatment?
Conservative and surgical.
What is conservative treatment for hernia?
Identifying risk factor for hernia and treating them.
How are hernias resolved surgically?
Excise the hernial sac (to cut out), and the defect closed – sometimes with a polypropylene mesh. There should be no tension in the sealed wound.
What is the surface anatomy of the inguinal ligament?
Line between the pubic tubercle and the anterior superior iliac spine. The inguinal ligament creates a crease in the skin which creates the definitive ‘V-lines’.
How is the iliac tubercle palpated?
On skeleton, it is laterally projecting bony tip 5cm behind the ASIS – so, on your side. At the L5 level.
What is the surface anatomy of the ASIS?
Found at the S2 vertebral level and is the projection on the anterior region of the abdomen and quite lateral.
Difference between pubic symphysis and tubercle? And how to palpate?
Symphysis – cartilaginous joint that sits between and joins left and right pubic bones. Tubercle – forward-projecting tubercle on the upper border of the medial portion of the pubis. Can be felt in the pubic area.
What is the mid-inguinal point?
Mid-point of a line joining pubic symphysis and ASIS.
What is the trans-tubercular plane? Alternative name?
Horizontal plane at the L5 level. Also called the intertubercular plane. Goes through the RIGHT and LEFT ILIAC TUBERCLES.
What is the subcostal plane?
Horizontal plane across the right and left costal margins in the mid-axillary line i.e. the lowest edge of the 10th costal cartilage. At the L2/3 level.
What is the position of the umbilicus in relation to the lumbar curvature?
L3/4.
What is the transpyloric plane?
Horizontal plane at the level of the tips of the right and left 9th costal cartilages. At the L1 level.
What is the supra-cristal plane?
Horizontal plane through the highest point on the iliac crest. Passes at the L4 level.
How is anterior abdominal wall divided into 9 regions?
MID-CLAVICULAR PLANES: vertical lines are drawn from the mid-clavicular to mid-inguinal points on each side. SUBCOSTAL PLANE: horizontal line joining the right and left costal margins in the mid-axillary lines. INTERTUBERCULAR PLANE: goes through right and left iliac tubercles.
How laterally do the rectus abdominus extend in the anterior abdominal wall?
Most lateral part touches the mid-clavicular plane.
What is the PSIS? Surface anatomy?
Posterior superior iliac spine found at the S2 level. It is directly posterior to the ASIS and marks the middle of the sacroiliac joint. At the surface, both PSIS are found as depressions of skin just above the buttocks.
What is a sacral dimple?
Found at the S2 level, and a prominent dimple found on the midline above the buttocks. It is a defect found in a small proportion of the population.
What is the sacroiliac joint?
The joint between the sacrum and the pelvis.
Describe the Peritoneum
•Lines the abdominal cavity.
•SINGLE continuous membrane of simple SQUAMOUS epithelium – MESOTHELIUM.
What is the peritoneal cavity
- The peritoneal cavity is a POTENTIAL space within the layer of peritoneum.
- Components of the GI tract are suspended in peritoneal reflections – MESENTERIES.
Viscera in the thoracic cage
Liver, Gall Bladder, Transverse Colon, Stomach, Spleen