Applied Anatomy of the
Lymphatics
F. P. Millard, D.O.
1922
CHAPTER THREE
APPLIED ANATOMY OF LYMPHATICS OF THE HEAD AND
NECK
In Relation to Acute Poliomyelitis
We have already mentioned that the most direct area
of infection in infantile paralysis is through the membranes of the nose
and throat. The virus gains entrance during respiration and deglutition.
We have also referred to the mode of infection through
the alimentary tract. The virus is carried along with the bolus of
food and enters the stomach. During the process of digestion it is
conveyed to the intestinal tract and the system takes up the virus and
its poisons by way of the lacteals and blood channels.
A more direct infection of the central nervous system
may take place through the lymphatics of the head and neck. The membranes
of the nose, nasopharyngeal region and mouth are rich in lymphoid tissue.
The close connection between the lymphatic tissues of these areas and those
found in the head and neck allow a conveyance of the virus to the membranes
of the brain and spinal cord. The openings for communication are
numerous and the paths for the conveyance of infection are closely connected.
The superficial and deep lymphatic vessels and nodes found in the neck
and throat allow of ready communication and transmission of the micro-organisms
and their toxic products. The central nervous system may be almost
directly invaded by the virus found in the membranes and lymphatics of
the nasopharyngeal region. Once the virus reaches membranes protecting
the central nervous system the upward invasion to the brain from the cervical
region is readily accomplished.
The cerebro-spinal fluid surrounding the cord also
supplies the area around the brain. There is a communication between
the cord and brain, as the same coverings that surround the cord are continuous
with those covering the brain.
One of the most noticeable symptoms in an acute case
of infantile paralysis is headache. There is also pain in the neck.
The temperature increases in a typical case until it reaches 103 degrees
or more. The congestion in the head and neck is marked. The
neck seems swollen; the lymph nodes are enlarged and indurated. The
lymphatics are involved as well as the blood vessels. The lymphatics
have carried the virus to the hidden membranes of the central nervous system.
The invasion may have taken the route found in the
cervical region, the cephalic membranes first becoming infected.
The virus in this case must needs travel downward in the central nervous
system if the case is one that is not abortive in type. General infection
of the cord may or may not take place. The cephalic membrane involvement
may be sufficient to cause a bulbar paralysis which will eventually affect
all points below and prove fatal in nature if sufficient destruction takes
place. Again, it is the amount of resistance the tissues have that
will determine the extent of the destruction in the nerve cells.
The lymphatic engorgement will depend upon the lack of freedom of circulation
and the quality of the blood and lymph.
The nodules will indurate in proportion to the amount
of blockage. The more regular the circulation the better the oxygenation
of the blood will be, and good blood, well acrated, is the best of germicides.
The microorganisms lose their power in proportion to the vitality of the
tissues they have to work in.
The extreme amount of congestion in the head and
neck is due in part not to the virulence of the virus as much as to the
amount of obstruction found in relation to the blood vessels and lymph
channels.
The involvement of the lymphatics is due in the first
place to the more ready infection and conveyance of the virus by the fact
that the tissues in which these vessels are found were devitalized by obstructed
or impeded circulation.
The normal tissues in the pharyngeal and nasal regions
of a child will not harbor nor convey to the same extent the virus as in
the case of a child in which adenoid growths and diseased tonsils are found.
The child with polypi and congested turbinate processes will likewise harbor
germs and propagate them in a soil that is suitable for germ development
through obstructed lymph and blood channels.
The cause of this static condition in the sinuses
of the head and the membranes lining these as well as lining the pharyngeal
region may be due to a variety of lesions. There is always a possibility
of hereditary weakening or diathesis with nervous instability, but we will
discuss here the part the osseous lesions play in the role of primary causative
factors.
PLATE VIII. Vascularization
of the central nervous system from which the lymph spaces receive their
supply.
The drainage of the lymphatics of the head and neck
is quite the same on both sides. Below the neck and for the rest
of the body we find a vastly different proposition. The lymphatics
of both sides of the head and neck tend to pass downward to a common collecting
centre, the subclavian veins. The superficial communicate in some
instances with those of the opposite side. Normally the nodes are
not over-sensitive unless pressed upon. Induration is pathological
if found to any extent. The same rule that governs the freedom of
circulation of blood is more or less applicable to that of the lymph channels.
Lesions that contract muscular tissue will obstruct lymph channels the
same as they will obstruct the blood vessels. Not all lymphatics
have vasomotors supplying them, it is true, but there are other ways of
obstructing the flow of lymph and blood than through the vasomotor nerves.
The lesions mentioned under the heading of “Cervical” in the preceding
chapter are applicable to lymph channels as well as to the blood vessels.
The lesions that produce a congested condition of the tonsils will invariably
affect the lymphatics that are so abundant in this region. The lymphatic
tissues that form the outer and inner defences of the naso-pharyngeal region
suffer obstruction and nodular enlargement whenever there is venous stasis.
The involvement of the membranes of the sinuses of
the head are either secondarily or simultaneously affected through a vascular
disturbance in the vault of the pharynx and the region of the nose.
The congestion in the membranes protecting the central
nervous system are the effects of lymph and blood vessel obstruction through
a lesion of some nature -- osseous or otherwise. Before congestion
there must be obstruction, and before invasion and toxic poisoning from
virus there must be a suitable soil or else the tissues would produce an
abortive condition.
Thus we see first, last and always the greatest preventataive
measure in infection of any nature will be the maintenance of normal circulation
both in the lymph channels and in the blood vessels. This accounts
for the numerous cases of the abortive type of infantile paralysis, and
also the noted fact that in many instances only one or possibly two in
a family of several children contract the contagion; the others not becoming
infected.
Fortunately, the microorganism of infantile paralysis
does not attack children as numerically as the germs that are connected
with some of the other and more common diseases. In scarlet fever,
measles, whooping cough, etc., there seems to be a condition that makes
the contagion spread with a more decided virulence. It is not uncommon
to see these children’s diseases go right through the family.
PLATE IX. The lymph
spaces found in the membranes of the cord are numerous. Right
lateral view of cord and the formation of spinal nerves. The lymph
bathing the cord and spinal nerves is found in abundance. -- (1)
Anterior horn. (2) Posterior horn. (3) Anterior median
fissure. (4) Posterior spinal nerve roots. (5) Ligamentum denticulatum.
(6 & 8) Dura mater. (7) Posterior ganglion.
PLATE X. Anterior view of
the cord and membranes. The lymph bathes all these cells and tissues. (1)
Posterior horn. (2) Anterior horn, (3) Spinal nerve with covering. (4)
Dura matter. (5) Turned back. (6) Spinal cord bared. (7) Arachnoid. (8)
Anterior nerve roots. (10) (Top number) Lateral surface of cord. (10) Anterior
nerve passing through dura mater.
In infantile paralysis the central nervous system
is directly involved, and the child who, due to lowered tissue resistance
from spinal lesions and other conditions, furnishes the most suitable tissue
soil, is the one that will be the victim. The others may have the germs
in their mucous membranes, but the soil is not favorable to infection and
they will have simply an abortive type or will not be affected in the least.
The obstruction of the lymphatics may be due to a
secondary condition. The presence of stasis in the region of the tonsils
may he somewhat chronic in nature. There may be repeated attacks of tonsillitis
which may last only a day or two. The disturbance may be almost wholly
vascular. Should the obstruction persist and the lymph nodes become enlarged
there will be a lymphatic involvement that will tend to complicate matters.
Infection will be a natural sequence. The correction of an atlas
or axis lesion that will remove any disturbance to the superior cervical
ganglion with its postganglionic fibres that control the vasomotors to
that region where stasis has been present will reestablish normal lymph
flow.
Lymphatic involvement may be secondary to a vasomotor
disturbance to the blood vessels in the same region when congestion exists.
The hyoid bone slightly misplaced will put tension upon one set of the
muscles attached to it and cause not only venous stasis but a blocking
of the lymph channels, and as a result we will note nodular enlargement
in the lymphatic chains. The enlargement of the nodes in the region of
the mastoid may be due to an obstruction of the lymphatic channels in the
region of the clavicle. The backward luxation of the clavicle with a subluxated
first rib may obstruct the drainage of the lymph into the subclavian veins.
The middle cervical ganglion may be involved and
we may have a thyroid disturbance as well as cardiac irregularity through
a cervical lesion. This may in turn cause pressure by thyroid enlargement
upon the lymph channels and produce toxic poisoning of the membranes and
tissues in the throat, head and central nervous system.
The presence of an aneurysm may, through mechanical
pressure, cause a greater disturbance than any single osseous lesion. A
cervical rib may cause irritation of the brachial plexus and the sympathetic
system that will not be relieved until surgical measures are used. Not
all disturbances are from osseous lesions in the way of vertebral rotation
or subluxations, and not all disturbances are from local interferences.
The lymph channels may be affected and infected through disorders in the
axillary and mammary region, or even lower down. There is a communication
between the lymph channels of the thorax and cervical
region back of the clavicles. That is why no diagnosis is complete that
does not include a complete systemic survey in each instance. The high
temperature of a child or an adult may be lowered by a single adjustment
in the upper thoracic, or a similar effect may be brought about through
the correction of a cervical lesion. The idea is to determine the exciting
cause, if from a lesion, and correct the irregularity if it is at all possible
to do so.
PLATE XI. Posterior
view of spinal cord. The lymph blocked in acute poliomyelitis prevents
the nerve and cord cells from functioning properly.
Lymphathics of the Thorax and Abdomen
Infection almost invariably complicates the lymphatic
system. We are prone to think only of the veins conveying impure blood
and producing congestion and stasis, but we must remember always that the
lymph channels are the conveyors of toxic products, and blockage in a node
or number of nodes will affect the elimination or retard the disemination
of toxic products.
There is a possibility of the virus found in infantile
paralysis cases entering through the bronchial tubes and infecting the
tissues in relation to the roots of the lungs. Dust particles include germs,
and their entrance via the bronchioles may cause infection and enlargement
of the lymph nodes in that area.
There is a possibility of the virus or microorganisms
of infantile paralysis lodging and becoming scattered through the lymphatics
in the thoracic region in relation to the bronchial terminations.
Around the cord the pia mater and arachnoid harbor
lymph space. These spaces are in communication with the vessels, and it
is through them infection enters the cord substance.
In the abdomen below the diaphragm the cisterni chyli
is located. Into this receptum the intestinal lymphatic drainage enters
and the beginning of the thoracic duct is found. This duct collects from
the abdominal viscera and passes through the diaphragm in relation to the
aorta.
The lacteals carry away some of the chyle absorbed
from the small intestines and convey the substance to the thoracic duct
that passes upwards to empty into the subclavian vein on the left side.
The peritoneum is a lymphatic sac in one respect.
The amount of absorption that takes place in the peritoneum is great.
The food taken into the stomach containing the microorganisms
of infantile paralysis are readily absorbed by the lymph channels and conveyed
to the blood circulation.
The possibilities of mixed infection is worthy of
consideration. If a lymph channel is already infected by other germs, it
is in no condition to combat the virus of infantile paralysis should it
be absorbed.
The lymphatic system is in danger of blockage and
sluggishness the same as the vascular system. The normality of the
nodes and channels of the lymphatic system will depend to a great extent
upon the condition of the blood vessels and the tone of their walls.
If we find stasis in the mesenteric blood vessels we are likely to find
nodular enlargement of the lymphatic system. The numerous nodes found
in the mesentery and along the vessels of the bowels are normal only so
long as the blood stream to and from the abdominal viscera is normal.
A diseased organ is one that has a disturbed circulation regardless of
the cause. If an organ is functioning abnormally we invariably find
its vascular supply disturbed. If an organ is mechanically interfered
with we also find the circulation to that organ affected. The cause
being removed the circulation may once more be re-established.
The infection of an organ is through its vasacular
channels, either the blood or the lymph. The better the circulation
the less chance of germ invasion. The more perfect the assimilative
mechanism the less liable the virus to be disseminated and propagated.
Lymph spaces are found around the cord in all regions.
The vascularization of the cord is complete at every segment. The
entrance of germs at any point is possible. The normality of the
lymph spaces in relation to the pia mater will depend to a great extent
upon the normality of the vascular system in relation to the cord and its
membranes.
If there exist lesions at any point along the length
of the cord we at once find a lowered tissue resistance to that area of
the cord.
PLATE XII. Vascularization
of a section of the spinal cord, showing the three spinal arteries and
correlating spinal branches from the intercostal. The cerebro-spinal
fluid is of a lymph formation, and the area is bathed by this fluid also.
There may be a trophic disturbance or a vasomotor
instability to the vessel walls, or we may find stasis from a contractured
musculature that will block the lymph spaces. In any of these conditions
the tissue vitality will be undermined and invasion is more apt to take
place.
In the thoracic region we may find costal lesions
as well as vertebral. The relation of the intercostal vessels to
the ribs may, in a costal subluxation, so disturb the sympathetic ganglia
that the tissues around the foramina will become irritated, and this will
extend into the cord through the blood channels.
The blockage of one vessel to the cord and membranes
may so lower the nerve and cell integrity that a cord segment will become
readily infected by the virus.
Remember that the cord segments and their cells must
be kept at a certain tone from a vascular standpoint or else the cells
will not function normally. In the ventral portion of the grey matter
of the cord the motor cells send forth their efferent impulses, and the
muscular tone of the limbs will depend upon the normality of these impulses
for their strength and motion. The lowered tone through disturbed
vascularization, plus the invasion of the virus or its toxins, even in
a mild or abortive case, will cause a disturbance to the efferent tracts
in proportion to the degree in which the cells resist the attack.
In the more severe cases of infantile paralysis,
where exudation accompanies congestion, we note a marked destruction of
the motor area.
If the spinal arteries and veins are obstructed to
any extent the lymph spaces are occluded, and nature’s effort to clear
the condition is sorely handicapped. Thus we see the prime importance
of keeping a child’s spinal tissues up to normal so that should the virus
gain entrance to the body there will not be lowered tissue resistance in
the region of the central nervous system.
The region of the diaphragm, with its many openings
for the passing of nerves, vessels, tubes, etc., is of interest.
The presence of lower rib lesions or vertebral misplacements may so affect
the attachments of the diaphragm and its crura that the openings found
in its central tendon and in the region in relation to the vertebral column
may cause undue pressure or obstruction to these various tubes, vessels
and nerves.
PLATE XIII. General
Scheme of Lymphatics.
The veins and thoracic duct are passing upward; the
nerves, aorta and esophagus are going downward. All have their functions
and any minor obstruction may cause a systemic disturbance.
The thoracic duct has a few valves to prevent backward
flow. It is a long tube, and gravity is against it the same as in
the saphenous veins. This duct has its vascular supply and nerve
tone, although it has not the marked muscular tissue within its walls that
is found in the blood vessel walls. The thoracic duct is a great
collecting system and the flow of lymph must be emptied into the veins
as regularly as possible.
From the fact that the lymphatic system has to deal
with toxic products, we must at all times determine the condition of this
duct and see that no lesion exists that will in any way affect its walls
or its conveying properties.
The cisterni chyli is located in front of the second
and third lumbar vertebrae. Lesions that are found at this region,
or even higher, including lower costal, may have a marked effect upon the
receptive properties of this collecting system.
The drainage of the mesenteric nodes into this cistern
will depend upon the normality of the blood vessel circulation. The
presence of obstipation, with poor peristaltic action, the finding of adhesions
or the noting of growths and thickening of the tissues, all have a bearing
upon the lymphatic system. Splanchnoptosic conditions will affect
drainage and obstruct the lymph channels. This will lower the general
tone of the tissues. In children colic, convulsions and constipation
will lower the vitality.
The tissues of the entire body in the child are not only growing,
but must be sustained in the way of complete nourishment as well.
In the adult the growth is complete and sustenance alone is
required. The activity of a child is much greater than in the adult,
as a rule. The resiliency of the tissues is greater, and the bones
are not as yet completely ossified. He takes up shock better than
an adult, and the nerves do not seem to suffer from accidents as do those
of the adult.
PLATE XIV. -- Section of
the spine. A vertebra with the spinal cord and its membranes.
The small cut to the left is an enlarged section of the cord. Lymph
spaces are found in this area.
The common point of tissue irritability is when we
find a lesion from a fall or strain. The disturbance to the vessels
and nerves, unless the proper adjustment is made, will continue to lower
tissue resistance through nerve irritation. If the sympathetic chain
is involved through its connection with the spinal nerves, the vasomotors
will suffer from impeded circulation, and the impulses will become irregular.
The spine of a child from the time it is born must
be inspected if we wish to keep him free from lesions and scoliosis.
Some children grow up with amost perfectly aligned spines, while others,
through traumatism, suffer irregularities that adjustment alone will rectify.
PLATE XV. The spinal cord
and nerves exposed. The lymph bathes the entire tract.