1196 SURFACE AND SURGICAL ANATOMY. 
lumbar spines, the pylorus itself bemg situated 1 in. to the right of the twelfth 
dorsal spine. The lesser curvature lies to the left of and below the tenth and 
eleventh dorsal spines. 
Viewed from behind, the large intestine on both sides overlaps the outer border 
of the kidneys and les parallel to the outer border of the erectores spine muscles. 
The peritoneum is reflected from the colon on to the posterior abdominal wall along 
a line drawn vertically upwards from the centre of the iliac crest, The splenic flexure, 
which reaches up to the level of the twelfth dorsal spine and the tenth rib, lies 
about 5 in. above the iliac crest. The hepatic flexure lies on a level with the first 
lumbar spine. 
Spleen.—The convex, postero-external, or diaphragmatic surface of the spleen is 
overlapped by the ninth, tenth, and eleventh ribs, the long axis of the organ nearly 
corresponding to that of the tenth rib (Fig. 785, p. 1150). The spleen is placed 
further back than is often supposed, its postero-internal or vertebral angle (apex of 
spleen, according to Cunningham) being situated on a level with,-and 13 in. external 
to, the tenth dorsal spine. Its antero-external angle (anterior basal angle of 
Cunningham), which lies on a level with the twelfth dorsal spine, reaches forwards 
as far as the mid- axillary line, where it is overlapped by the tenth rib. The 
posterior basal angle lies on a level with, and about 4 in. external to, the first 
lumbar spine, in a line drawn vertically upwards from a point 1 in. behind the 
centre of the iliac crest. This angle is situated opposite the eleventh intercostal 
space, behind the upper part of the descending colon and immediately external to 
the middle of the outer border of the kidney. 
Having placed a mark on the skin corresponding to these three angles, the out- 
line of the or gan 1s delimited as follows : Commencing at the vertebral angle, the 
upper border is arched upwards so as to reach the level of the ninth rib in the 
scapular line, thence it descends across the posterior axillary line, as the so-called 
anterior notched border, to end in the mid-axillary line at the antero-external angle. 
The postero-inferior or renal border is drawn from the, vertebral to the inferior 
(posterior basal) angle along the eleventh intercostal space. The short antero- 
inferior border unites the anterior and posterior basal angles. The upper third of 
the spleen is overlapped by the base of the lung ( diaphragm and pleura interven- 
ing), which crosses it horizontally at the level of the tenth dorsal spine; hence the 
upper limits of the spleen cannot be defined by percussion. The postero-interior 
limit of the splenic dulness merges into that of the kidney and the thick 
muscular tissues of the lom. The only parts of the splenic outline, therefore, 
which can be defined by percussion are part of the upper arched border, and the 
antero-external and short antero-inferior borders. The dull area les between the 
posterior and mid-axillary lnes, and reaches down to within about two inches of 
the costal region. 
Pancreas.—The head of the pancreas hes opposite the last dorsal and _ first 
lumbar spines ; the tail lies at the same level as the splenic flexure of the colon, a 
little above the posterior basal angle of the spleen (Fig. 755, p. 1089). 
TABLE INDICATING THE LEVEL OF THE MORE IMPORTANT STRUCTURES IN 
RELATION TO THE SPINES OF THE VERTEBRA 
| Spines of Vertebre. | Origins of Spinal Nerves. Level of other Structures. 
Cervical ‘ 2 Cervical .| Soft palate. 
2 Ek ; 3 and 4 se E Isthmus of fauces. 
3 y oie Ss . Upper part of epiglottis. 
4. a Sal 6 vs ! Vocal cords. 
5 5: | "i es 2 Crico-thyroid membrane. 
p Arch of thoracie duct. 
» *  \ Commencement of trachea and cesophagus. 
| Lower end of cervical enlargement of cord. 
/ [Inferior cervical ganglion. 
Apices of lung. 
ie Dorsaley = : Oe abte, . Summit of arch of subclavian artery. 
land 2 Dorsal 
