ABDOMINAL SURFACE

ANATOMY & RELATIONSHIPS

by

O.W. Henson, Jr., Ph.D.

University of North Carolina, Chapel Hill

PLANES

a) Xiphisternal........................ T9

b) Transpyloric ...................... Ll, midway between upper border of symphysis pubis and jugular notch; midway between xiphisternal junction and umbilicus; Crosses point where lateral border of rectus abdominis muscles cross costal margin, i.e., tip of 9th rib.

c) Subcostal .......................... L3, (anteriorly at the lowest part of the margin of the 10th costal cartilage).

d) Transumbilical .................... Disc between L3 and L4.

e) Transcristal (supracristal.......... Spine of L4; extends across highest part of iliac crest.

f) Transtubercular (intertubercular). Spine of L5; at level of tubercle of iliac crest.

g) Transpinous (interspinous)....... Level of S2; through anterior superior iliac
spines.

ORGANS AND VESSELS

a) Inferior vena cava ................. Pierces diaphragm at T8; formed by confluence of common iliac veins at level of L5. Runs just to right of midline

b) Esophagus ......................... Pierces diaphragm at T10.

c) Aorta ................................ Pierces diaphragm at Tl2; celiac artery arises at this point. Divides at L4, just inferior to umbilicus; lies just to left of midline.

d) Superior mesenteric artery .. .... Origin at L1.

e) Inferior mesenteric artery ........ Origin at L3

f) Pyloris of stomach................ Transpyloric plane (L1).

g) Duodenum ........................ First part at L1; second part at L2; third part
crosses midline at L3; fourth part ascends to L2.

h) Gallbladder (tip) ................... At tip of 9th rib; where semilunar line meets costal margin in transpyloric plane.

i) Spleen............................... Lies along axis of left 10th rib.

j) Cecum and appendix.............. At McBurney's point; one third of the distance along a line extending from the right anterior superior iliac spine to the umbilicus.

k) Kidneys ............................ Tl2 to L3; hilus slightly below transpyloric plane. 12th rib cuts diagonally across kidney. Ascending colon ascends on anterior surface of right kidney; descending colon descends on anterior surface of left kidney. Medial surface lies against lateral margin of psoas major muscle.

l) Ureter............................... First part ca L2, covered anteriorly by second part of duodenum. Runs vertically down surface of psoas major muscle; lies close to tips of transverse processes of lumbar vertebra when viewed in AP radiographs.

m) Right colic flexure ................ Near tip of gallbladder, tip of 9th rib, against pylorus.

n) Fundus of stomach................ Surface under left dome of diaphragm. Marked by fundic air bubble in radiographs.

o) Root of mesentery................. Oblique line extending from ileocecal junction (McBurney's point) to duodenojejunal junction at L2.

p) Urinary bladder.................... Directly behind symphysis pubis; when full, it extends above the level of the symphysis.