Surface anatomy and surface markings
Be able to identify these landmarks on yourself or the patient .
The xiphoid.
The costal margin extends from the 7th costal cartilage at the xiphoid to the tip of the 12th rib (although the latter is often difficult to feel); this margin bears a distinct step, which is the tip of the 9th costal cartilage.
The iliac crest ends in front at the anterior superior spine from which the inguinal ligament (Poupart’s ligament) passes downwards and medially to the pubic tubercle. Identify this tubercle by direct palpation and also by running the fingers along the adductor longus tendon (tensed byflexing, abducting and externally rotating the thigh) to its origin at the tubercle.
Feel the firm vas deferens between the finger and thumb as it lies within the spermatic cord at the scrotal neck. Trace the vas upwards and note that it passes medially to the pubic tubercle and thence through the external inguinal ring, which can be felt by invaginating the scrotal skin with the fingertip.
Vertebral levels
•◊◊T9—the xiphoid.
•◊◊L1 — the transpyloric plane of Addison lies half-way between the suprasternal notch and the pubis, or approximately a hand’s breadth below the xiphoid. This plane passes through the pylorus, the pancreatic neck, the duodenojejunal flexure, the fundus of the gall-bladder, the tip of the 9th costal cartilage (felt as a distinct ‘step’), and the hila of the kidneys. It also corresponds to the level of termination of the spinal cord.
•◊◊L3 — the subcostal plane, a line joining the lowest point of the thoracic cage on each side, which is the inferior margin of the 10th rib. It passes through the origin of the inferior mesenteric artery
•◊◊L4—the plane of the iliac crests. This corresponds to the level of the bifurcation of the aorta. It is also a useful landmark in performing a lumbar puncture, since it is well below the level of the termination of the spinal cord, which is approximately at L1.
•◊◊The umbilicus is an inconstant landmark. In the healthy adult it lies at the junction of L3 and L4 vertebrae. It is lower in the infant and, naturally, when the abdomen is pendulous. It is higher in late pregnancy.
Surface markings
The abdominal viscera are inconstant in their position but the surface markings of the following structures are of clinical value.
X's mark the outline of the liver which reaches from the 5th intercostal space R to the 5th intercostal space L in mid clavicular line, and lower margin 10th rib The aorta bifurcates at L4 which is in line with the iliac crests
Liver
The lower border of the liver extends along a line from the tip of the right 10th rib to the left 5th intercostal space in the mid clavicular line; it may just be palpable in the normal subject, especially on deep inspiration. The upper border follows a line passing through the 5th intercostal space on each side.
Spleen
This underlies the 9th, 10th and 11th ribs posteriorly on the left
side commencing 2 in (5 cm) from the midline. It is about the size of the subject’s cupped hand.
Gall-bladder
The fundus of the gall-bladder corresponds to the point where the lateral border of the rectus abdominis cuts the costal margin; this is at the tip of the 9th costal cartilage, easily detected as a distinct ‘step’ when the fingers are run along the costal margin.
Pancreas
The transpyloric plane defines the level of the neck of the pancreas which overlies the vertebral column. From this landmark, the head can be imagined passing downward and to the right, the body and tail passing upwards and to the left.
Aorta
This terminates just to the left of the midline at the level of the iliac crest at L4; a pulsatile swelling below this level may thus be an iliac, but cannot be an aortic, aneurysm.
Kidneys
The lower pole of the normal right kidney may sometimes be felt in the thin subject on deep inspiration. Anteriorly, the hilum of the kidney lies on the transpyloric plane four finger breadths from the midline. Posteriorly, the upper pole of the kidney lies deep to the 12th rib. The right kidney normally extends about 1 in (2.5 cm) lower than the left. Using these landmarks, the kidney outlines can be projected on to either the anterior or posterior aspects of the abdomen. In some perfectly normal thin people, especially women, it is possible to palpate the lower pole of the right kidney and the sigmoid colon if loaded with faeces; in most of us, only the aorta is palpable.
Be able to identify these landmarks on yourself or the patient .
The xiphoid.
The costal margin extends from the 7th costal cartilage at the xiphoid to the tip of the 12th rib (although the latter is often difficult to feel); this margin bears a distinct step, which is the tip of the 9th costal cartilage.
The iliac crest ends in front at the anterior superior spine from which the inguinal ligament (Poupart’s ligament) passes downwards and medially to the pubic tubercle. Identify this tubercle by direct palpation and also by running the fingers along the adductor longus tendon (tensed byflexing, abducting and externally rotating the thigh) to its origin at the tubercle.
Feel the firm vas deferens between the finger and thumb as it lies within the spermatic cord at the scrotal neck. Trace the vas upwards and note that it passes medially to the pubic tubercle and thence through the external inguinal ring, which can be felt by invaginating the scrotal skin with the fingertip.
Vertebral levels
•◊◊T9—the xiphoid.
•◊◊L1 — the transpyloric plane of Addison lies half-way between the suprasternal notch and the pubis, or approximately a hand’s breadth below the xiphoid. This plane passes through the pylorus, the pancreatic neck, the duodenojejunal flexure, the fundus of the gall-bladder, the tip of the 9th costal cartilage (felt as a distinct ‘step’), and the hila of the kidneys. It also corresponds to the level of termination of the spinal cord.
•◊◊L3 — the subcostal plane, a line joining the lowest point of the thoracic cage on each side, which is the inferior margin of the 10th rib. It passes through the origin of the inferior mesenteric artery
•◊◊L4—the plane of the iliac crests. This corresponds to the level of the bifurcation of the aorta. It is also a useful landmark in performing a lumbar puncture, since it is well below the level of the termination of the spinal cord, which is approximately at L1.
•◊◊The umbilicus is an inconstant landmark. In the healthy adult it lies at the junction of L3 and L4 vertebrae. It is lower in the infant and, naturally, when the abdomen is pendulous. It is higher in late pregnancy.
Surface markings
The abdominal viscera are inconstant in their position but the surface markings of the following structures are of clinical value.
X's mark the outline of the liver which reaches from the 5th intercostal space R to the 5th intercostal space L in mid clavicular line, and lower margin 10th rib The aorta bifurcates at L4 which is in line with the iliac crests
Liver
The lower border of the liver extends along a line from the tip of the right 10th rib to the left 5th intercostal space in the mid clavicular line; it may just be palpable in the normal subject, especially on deep inspiration. The upper border follows a line passing through the 5th intercostal space on each side.
Spleen
This underlies the 9th, 10th and 11th ribs posteriorly on the left
side commencing 2 in (5 cm) from the midline. It is about the size of the subject’s cupped hand.
Gall-bladder
The fundus of the gall-bladder corresponds to the point where the lateral border of the rectus abdominis cuts the costal margin; this is at the tip of the 9th costal cartilage, easily detected as a distinct ‘step’ when the fingers are run along the costal margin.
Pancreas
The transpyloric plane defines the level of the neck of the pancreas which overlies the vertebral column. From this landmark, the head can be imagined passing downward and to the right, the body and tail passing upwards and to the left.
Aorta
This terminates just to the left of the midline at the level of the iliac crest at L4; a pulsatile swelling below this level may thus be an iliac, but cannot be an aortic, aneurysm.
Kidneys
The lower pole of the normal right kidney may sometimes be felt in the thin subject on deep inspiration. Anteriorly, the hilum of the kidney lies on the transpyloric plane four finger breadths from the midline. Posteriorly, the upper pole of the kidney lies deep to the 12th rib. The right kidney normally extends about 1 in (2.5 cm) lower than the left. Using these landmarks, the kidney outlines can be projected on to either the anterior or posterior aspects of the abdomen. In some perfectly normal thin people, especially women, it is possible to palpate the lower pole of the right kidney and the sigmoid colon if loaded with faeces; in most of us, only the aorta is palpable.
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