Referred pain

Question 1

what is referred pain?

Answer 1

the perception of visceral pain some way away from the organ involved

Question 2

what sort of nerve fibre is visceral pain transmitted along?

Answer 2

afferent autonomic nerves (visceral afferent)

Question 3

where can autonomic afferent nerve fibres enter the CNS?

Answer 3

only where visceral efferent fibres leave it

Question 4

somatic pain

Answer 4

pain arising from the skin
sensitive, well-localised, often sharp
many sensory receptors

Question 5

visceral pain

Answer 5

fewer sensory endings in viscera
often in SM
pain poorly localised
dull, heavy or gripping
may be referred

Question 6

what sensations are viscera insensitive to?

Answer 6

crushing, cutting, burning

Question 7

what can cause pain in the viscera?

Answer 7

excessive stretching/contraction of their walls

Question 8

what is a difference between visceral afferent and visceral efferent fibres?

Answer 8

visceral afferent fibres don’t have a peripheral synapse

Question 9

visceral afferent fibres

Answer 9

join a spinal or cranial nerve and enter the CNS along a dorsal nerve root
cell body is found in the dorsal root ganglion

Question 10

mechanism for referred pain?

Answer 10

nociceptors from several locations converge on a single ascending tract in the spinal cord
pain signals from the skin are more common
brain associates activation of the pathway with pain in the skin (brain confuses it with somatic part of pathway and thinks signals are coming from skin)

happens when nerve fibres from regions of high sensory input (such as skin) and nerve fibres from regions of normally low sensory input (such as internal organs) happen to converge on the same levels of the spinal cord

Question 11

where might pain be felt from a myocardial infarction and why?

Answer 11

base of neck, jaw, shoulder and arm
pain signals from the heart enter the spinal cord at T1-4/5. When these regions are activated, brain thinks that the pain is coming from the skin there

Question 12

where is pain from foregut structures felt?

Answer 12

epigastrium

Question 13

where is pain from midgut structures felt?

Answer 13

umbilicus

Question 14

where is pain from hindgut structures felt?

Answer 14

hypogastrium (sigmoid and rectum - S2-4)

Question 15

where might pain from the appendix be felt?

Answer 15

right lower quadrant, umbilicus

Question 16

where might pain from the bladder be felt?

Answer 16

lower abdomen and upper thighs

S2-4, T12-L2

Question 17

where might pain from the diaphragm be felt?

Answer 17

shoulders

Question 18

where might pain from the oesophagus be felt?

Answer 18

along sternum, left upper thorax

Question 19

where might pain from the intestines be felt?

Answer 19

back (backache or sharp pain in the back), umbilicus

Question 20

where might pain from the kidneys be felt?

Answer 20

posterior costovertebral angle, radiating forward around the flank
T10-L1

Question 21

where might pain from the liver be felt?

Answer 21

right shoulder

Question 22

where might pain from the pancreas be felt?

Answer 22

directly behind the pancreas, lower left quadrant, umbilicus

Question 23

where might pain from the spleen be felt?

Answer 23

left shoulder and upper third of arm

Question 24

where might pain from the ureter be felt?

Answer 24

costovertebral angle, radiating to the lower abdomen, testicles and inner thigh
L1/2

Question 25

where might pain from the uterus be felt?

Answer 25

T12-L1

Question 26

where might pain from the cervix be felt?

Answer 26

S2-4