D. J. (Daniel John) Cunningham.

Cunningham's manual of practical anatomy (Volume 1) online

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Lateral epicondyle -^ j M

Medial epicondyle -4"T~J /

Ant. sup. spine of ilium

Greater trochanter ^
Styloid process of radius
Styloid process of ulna V



Junction of manubrium
With body of sternum




Medial condyle of femur

Lateral condyle of femur

Patella

Lateral condyle of tibia
Head of fibula




Symphysis
of pubis
Distal end of

radius



Lateral malleolu



FIG. 104. Anterior Surface of Body.

prominent landmarks of the anterior, medial, and lateral
femoral regions and of the anterior region of the knee.



220 THE INFERIOR EXTREMITY

A faint sulcus at the proximal extremity of the anterior
region is the boundary line between the inguinal region of the
abdomen and the subinguinal region of the thigh. The
resistance felt deep to the sulcus is due to the ligamentum
inguinale, which is attached, at the lateral and superior end
of the sulcus, to the anterior superior iliac spine, and, at its
inferior and medial end, to the pubic tubercle. From the
anterior superior iliac spine the iliac crest can be traced
backwards to the posterior superior spine ; from the pubic
tubercle the ringer should be carried medially, along the pubic
crest, to the upper end of the symphysis pubis. Next, the finger
should be passed downwards, along the front of the symphysis
pubis, to the apex of the pubic arch and thence downwards and
backwards along the rami of fas. pubis and ischium, which mark
the superior boundary of the medial femoral region, to the tuber
ischiadicum. About ten centimetres below the highest part
of the iliac crest, and on the plane of the pubic crest, is
the trochanteric region, indicated by an eminence due to the
prominence of the trochanter major of the femur. Above the
trochanteric region, and between it and the iliac crest is the
region of the hip (regio coxce), and below the troehanteric region is
the lateral femoral region. At the distal end of the anterior
part of the thigh is the regio genu anterior. In the centre of
the anterior part of the knee lies the patella or knee- cap, the
outline of which can be seen as well as felt. From the distal
end of the patella the ligamentum patella should be followed
to the tuberosity of the tibia.

At the distal end of the lateral region of the thigh the
outline of the lateral condyle of the femur is easily recognised.
Directly distal to it is the lateral condyle of the tibia, and at
the distal and posterior part of the latter is the head of the
fibula. The tendon which can be traced proximally from the
head of the fibula, on the border line between the lateral
and posterior femoral regions, is the tendon of the biceps
femoris ; and the dense, longitudinal band of fascia immedi-
ately anterior to the tendon of the biceps is the ilio-tibial
tract of the fascia lata a fascial band which is more easily
distinguishable in the living than in the dead body.

At the distal end of the medial part of the thigh is the
outline of the medial condyle of the femur, which should be
palpated ; and immediately distal to it the medial condyle
of the tibia is easily recognised beneath the integument.



THE THIGH 221

The tendons behind the medial condyle of the femur are
more easily felt in the living than the dead body ; they are
the tendons of the semitendinosus and semimembranosus
muscles. The less easily palpated tendon of the adductor
magnus should be distinguished as it descends to the proximal
border of the medial femoral condyle.

The dissector should verify all these points of surface
anatomy not only on the dead body but also on the bodies
of himself and his friends, and he should examine them
repeatedly until he is quite familiar with them both by sight
and by touch.



THE ANTERIOR FEMORAL AND MEDIAL FEMORAL REGIONS
AND THE ANTERIOR REGION OF THE KNEE.

Superficial Dissection. This dissection comprises the
examination of the following parts :

1. Superficial fascia.

2. The great saphenous vein and its tributaries.

3. The superficial external pudendal artery.

4. The superficial epigastric artery.

5. The superficial circumflex iliac artery.

6. Lymph glands and vessels.

7. The fossa ovalis.

8. Cutaneous nerves.

9. The fascia femoris (deep fascia of the thigh).
10. The bursse patellae.

Dissection. Reflection of the Skin. Incisions. (i) From
the anterior superior iliac spine along the line of the inguinal
ligament to the symphysis pubis ; (2) from the medial extremity
of the first incision downwards along the margin of the scrotum,
then along the junction of the medial with the posterior aspect
of the thigh and across the medial aspect of the knee to the
level of the tuberosity of the tibia ; (3) from the distal end of the
vertical incision transversely across the anterior surface of the
leg to its lateral border. The quadrilateral flap of integument,
thus mapped out (9, Fig. 104), must be raised carefully from
the subjacent superficial fascia and turned laterally, particular
care being taken in the region of the knee to avoid injury to
the patellar plexus of cutaneous nerves.

To make a clean incision through the skin hold the scalpel
at right angles to the surface and force the point through the
skin into the subjacent soft superficial fascia at the point of
commencement of the incision, then incline the blade to an
angle of forty-five degrees and, pressing firmly on the back of
the blade with the forefinger, draw it along the line of incision.
When the opposite end of the incision is reached bring the
scalpel to a right angle with the surface again and withdraw it.



222 THE INFERIOR EXTREMITY

To reflect the skin take hold of the most convenient angle
of the flap the upper or the lower medial angle in the present
dissection with the forceps, and with the edge of the scalpel
detach it from the soft fat beneath.

As soon as the angle selected is sufficiently detached discard
the forceps, seize the detached angle between the thumb and
forefinger of the left hand, and pull it away from the fat, keeping
it stretched and tense ; then draw the edge of the scalpel across
the skin, at its junction with the fat, from one edge of the flap
to the other, always keeping the edge of the knife against the
skin. If the work is done properly the leathery-looking deep
surface of the skin will be entirely freed from fat, as the flap
is reflected, and the superficial nerves and vessels which lie in
the fat will not be injured. When the skin is reflected the
superficial fascia is exposed.

Superficial Fascia (Panniculus Adiposus). The superficial
fascia is found over the whole surface of the body. It varies
in structure in different parts, but in all parts, with the
exception of the region of the scrotum, it contains a greater
or a smaller amount of yellowish fat, the amount varying not
only with the part under consideration but also with the
general obesity or thinness of the subject In some regions,
such as the anterior part of the neck and the adjacent part of
the chest, reddish muscle fibres are present in the deeper part
of the fat ; in the scrotum the muscle fibres entirely replace
the fat. The fat is interspersed and divided into lobules by
lamellae of denser tissue called fibrous tissue, and in the deeper
part of the superficial fascia the fibrous tissue becomes more
predominant, forming a membrane which is the deeper or
membranous layer of the superficial fascia. In the superficial
fascia lie the cutaneous vessels and nerves and the deeper
parts of the hair follicles and skin glands and the superficial
lymph glands. Under the superficial fascia is a more firm
membranous layer, the deep fascia, surrounding the muscles
and deeper parts.

The superficial fascia intervenes therefore between the
skin and the deep fascia, and it is attached to both by fibrous
strands which pass through the fat. As it lies between the
skin and the deep fascia it provides a soft elastic cushion upon
which the skin rests, and which, by its elasticity, allows the
skin to be moved over the deeper parts. It rounds off the
angularities of the deeper parts and forms a bed in which
the cutaneous vessels and nerves ramify before they enter
the skin.

In most parts of the body the laxity of the superficial



THE THIGH



223



fascia allows the skin to be moved freely over the subjacent
deep fascia, but in other situations, such as the palms of the
hands and the soles of the feet, movement of the skin is
limited because the fibrous septa which pass from the skin to
the deep fascia are numerous and strong.

In the region now exposed the fat of the superficial fascia is
usually abundant. And the membranous deeper layer is well



fnQ/.Transversalis fascia

"Transversus abdominis
^""Internal oblique
31 External oblique



Transversalis'fascia



Skin

Camper's fascia
Scarpa's fascia

Inguinal ligament
Lyinph gland -

Fascia lata .




Ilio-psoas
Iliac fascia



FIG. 105. Diagram of the Fasciae and Muscles of the Inguinal and
Subinguinal Regions lateral to the Fossa Ovalis.

marked, especially in the proximal part of the region where
the lymph glands and the superficial vessels lie between the
two layers. Moreover, in the uppermost pait of the region
the deep membranous layer of the superfical fascia is closely
attached to the deep fascia immediately distal to the line of
the inguinal ligament, where it is continuous with the corre-
sponding layer of the superficial fascia of the abdominal
wall. This is a point of some practical importance, and to
demonstrate it the dissectors of the inferior extremity and the
abdomen must work in conjunction with each other. A



224 THE INFERIOR EXTREMITY

transverse incision must be made through the entire thickness
of the superficial fascia on the front of the abdomen from
the anterior superior spine of the ilium to the middle line of the
body. When the lower edge of the divided fascia is raised its
two layers are easily distinguished. The deeper membranous
stratum is known as Scarpa's fascia (Fig. 105). Insinuate
the fingers behind Scarpa's fascia between it and the pearly-
looking tendon of the external oblique muscle. Little
resistance will be encountered, for the fascia and the tendon
are only connected by some fragile areolar tissue, and the
fingers can be passed downwards as far as the inguinal
ligament. At or immediately beyond the inguinal ligament
the passage of the hand into the thigh is barred by the union
of Scarpa's fascia with the deep fascia of the thigh, which is
called the fascia lata. If the fingers are carried medially
along the line of union of the two fasciae, it will be found
that the line of attachment descends across the front of the
pubis to the rami of the pubis and ischium, that is, into the
region of the perineum, which is the interval between the thighs.
In the perineum the deep layer of the superficial fascia is no
longer called Scarpa's fascia ; it becomes Colics' fascia, and
has definite connections, which will be studied by the
dissector of the abdomen.

If urine or other fluid is effused into the anterior part of
the perineum, it cannot get into the medial femoral region
because of the attachment of the deep layer of superficial
fascia to the rami of the pubis and ischium and to the front
of the pubis, but it can ascend, in the areolar tissue between
the deep layer of superficial fascia and the deep fascia, to
the wall of the abdomen. Having reached the wall of the
abdomen it cannot descend into the anterior femoral region
because of the connection between the deep layer of the
superficial fascia and the fascia lata at or a short distance
distal to the inguinal ligament.

Dissection. The dissection of the contents of the super-
ficial fascia of the subinguinal and anterior femoral regions
is one of the most difficult dissections which fall to the
lot of the dissector of the inferior extremity. The structures
to be displayed are. (i) Four veins the great saphenous, the
superficial external pudendal, the superficial epigastric, and
the superficial circumflex iliac. (2 Three arteries the super-
ficial external pudendal, the superficial epigastric, and the
superficial circumflex iliac. (3) The proximal and distal groups
of subinguinal lymph glands and the lymph vessels which enter



THE THIGH 225

and leave them. The proximal group lies parallel with the
inguinal ligament, the distal group lies along the sides of the
proximal part of the great saphenous vein. (4) Six nerves
the ilio-inguinal, the lumbo-inguinal, the lateral cutaneous
nerve of the thigh, the intermediate cutaneous nerve of the
thigh, the medial cutaneous nerve of the thigh, the saphenous
nerve. The first three nerves mentioned are derived directly
from a plexus of nerves inside the abdomen called the lumbar
plexus and the last three are branches of the femoral nerve,
which is itself a branch of the lumbar plexus. (5) The fossa
ovalis. (6) The patellar bursa, and (7) the deep fascia of the
thigh.

Commence by cleaning the great saphenous vein. It is
easily found about the mid-length of the thigh, near the medial
border. Cut down upon it there and then, with the point
and handle of the scalpel, clean away the fascia from its walls,
but do not injure its tributaries. Follow the vein, distally, to
the posterior border of the medial side of the knee and, proximally,
towards a point situated about 4 cm. below and lateral to the
pubic tubercle.

As the proximal end of the vein is approached lift it from
the bed of superficial fascia in which it lies ; insert the handle
of the scalpel behind the vein and push it upwards, until it
slips through an opening in the fascia lata through which
the vein passes on its way to join to the femoral vein. The
opening in the fascia lata is the fossa ovalis. The layer
of the deep fascia which covers the fossa ovalis is called
the cribriform fascia. The centre of the opening is situated
about 35-40 mm. distal and lateral to the pubic tubercle,
and its distal margin is always easily demonstrated in the way
already indicated. Do not attempt at present to display its
other boundaries ; they will be dissected later. When the
proximal part of the vein is being cleaned a number of the more
distal subinguinal lymph glands will be seen, some lying lateral
and some medial to the vein. They are rounded or ovoid bodies
of greyish or yellowish-pink colour, and they vary greatly in
size, some being as small as a pin-head, others as large as a
large bean. Connected with them the dissector will find a
large number of fine white strands which are the lymph vessels
passing to and from the glands. Clean the glands and some of
the lymph vessels, but do not disturb them from their positions
at present. Then proceed to clean the other superficial blood-
vessels. They are the superficial external pudendal, the super-
ficial epigastric, and the superficial circumflex iliac veins and
arteries. Begin with the veins which terminate in the great
saphenous vein before it passes through the fossa ovalis. Follow
them from their terminations towards their commencements,
and at the same time clean the accompanying arteries, which
are branches of the femoral artery, but avoid injury to the
superficial lymph glands which will be met with as the dissection
proceeds. Two of the arteries, the superficial external pudendal
and the superficial epigastric, emerge through the fossa ovalis :
the superficial circumflex iliac artery will be found, as a rule,
piercing the deep fascia lateral to the fossa. The lymph glands
will be recognised by their firm consistence and their greyish or
yellowish-pink colour.

VOL. I 15



226 THE INFERIOR EXTREMITY

If the subject is a male the dissector will have noted that as
the superficial external pudendal vessels pass towards the
symphysis pubis they cross superficial to a thick cord, the
funiculus spermaticus, which emerges from the abdominal wall
above the pubic tubercle, and descends across the upper and
medial angle of the front of the thigh into the scrotum. In the
female the round ligament of the uterus, which is less prominent
and less easy to define, lies in the position occupied by the sper-
matic cord in the male. At the upper part of the lateral margin
of the spermatic cord look for the ilio-inguinal nerve which
leaves the abdomen with the spermatic cord and sends branches
to the upper and medial part of the thigh (Fig. 107).

When the ilio-inguinal nerve has been secured clean the
subinguinal lymph glands which lie along the line of the in-
guinal ligament, and trace some of the fine white lymph vessels
which enter and leave them. The subinguinal lymph glands
form two groups : a proximal group which lies parallel with
the inguinal ligament and a distal group, already displayed, at
the sides of the proximal part of the great saphenous vein.
Many of them are usually of fairly large size ; indeed they are
so large that, as a rule, they can be felt easily through the skin
in the living subject. They are recognised in the dissection, as
already stated, by their firm consistence and their yellowish-
pink colour (Figs. 105, 106).

After the lymph glands have been located and cleaned proceed
to define the lateral and superior borders of the fossa ovalis
(Fig. 1 06). Commence at its inferior border, which has already
been displayed. Note that as the inferior border, which is
called the inferior cornu, passes medially it blends with the
upper part of the fascia lata which covers the muscles of the
medial part of the front of the thigh ; that part of the fascia
is known as the pectineal part of the fascia lata to distinguish it
from that part of the deep fascia which lies lateral to the fossa
ovalis and is called the iliac part of the fascia lata.

The lateral end of the inferior cornu is continuous with the
falciform margin of the fossa ovalis which curves upwards and
medially to terminate in the superior cornu. The superior cornu
bends medially as the superior margin of the fossa and is
attached to the tubercle of the pubis and to the ligamentum
lacunare, which is an expansion of the medial end of the inguinal
ligament. The edge of the scalpel is needed to define the falci-
form margin and the superior cornu, for both are closely blended
with the cribriform fascia which extends across the fossa from
the falciform margin and superior cornu to the pectineal part of
the fascia lata.

Clear away the cribriform fascia, dissecting out the arteries
and lymph vessels which pierce it, and display behind it the
anterior wall of the femoral sheath, a layer of fascia, which
surrounds the femoral vessels. Insinuate the handle of the
scalpel between the falciform margin and the femoral sheath
to demonstrate their independence, then pass the handle of
the scalpel behind the medial border of the femoral sheath to
demonstrate the fact that the pectineal part of the fascia lata
passes behind the femoral sheath.

After the relations of the margins of the fossa ovalis have
been defined seek the remaining superficial nerves. Close to



THE THIGH 227

the falciform margin of the fossa ovalis find the lumbo-inguinal
nerve which pierces the fascia lata a short distance distal to the
inguinal ligament. About 50 mm. (two inches) distal to the
anterior superior spine of the ilium find the posterior branch of
the lateral cutaneous nerve of the thigh as it pierces the fascia lata
and 50 mm. more distally the anterior branch of the same nerve.
About midway between the lateral cutaneous nerve and the
great saphenous vein seek for the intermediate cutaneous nerve
of the thigh, and along the anterior margin of the great saphenous
vein, in the distal third of the thigh, look for the anterior branch
of the medial cutaneous nerve of the thigh. Follow the lateral,
the intermediate, and the medial cutaneous nerves towards the
patella, where they join the patellar plexus (Fig. 107). Behind
the great saphenous vein, near the knee, look for the posterior
branch of the medial cutaneous nerve. Near the distal end of
the medial femoral region in front of the great saphenous vein,
find the infra-patellar branch of the saphenous nerve and trace
it to the patellar plexus, then, at the posterior border of the
medial side of the knee, behind the great saphenous vein, find
the saphenous nerve itself as it pierces the deep fascia (Fig. 163).

Superficial Inguinal Vessels. - - Three small arteries,
termed the superficial epigastric, the superficial external
pudendal and the superficial circumflex iliac, pierce the deep
fascia of the thigh below the inguinal ligament, and radiate
from each other for the supply of the lymph glands and
integument of the subinguinal and inguinal regions. They
all spring from the femoral artery immediately after it enters
the thigh.

Art. Pudenda externa superfirialis. The superficial external
pudendal artery passes forwards, through the fascia cribrosa,
which is spread over the fossa ovalis, and runs medially and
upwards across the spermatic cord. It supplies the skin of
the scrotum and penis or labium majus (Fig. 106).

Art. Epigastrica superficialis. The superficial epigastric artery
also pierces the cribriform fascia, turns upwards and leaves
the thigh by crossing the inguinal ligament about its middle.
It is distributed chiefly to the skin on the front of the
abdomen.

Art. Circumflexa ilium superficialis. The superficial circum-
flex iliac artery pierces the fascia lata lateral to the falciform
margin of the fossa ovalis. It is very small, and courses
proximally and laterally, along the inguinal ligament, towards
the anterior superior spine of the ilium (Fig. 106).

The veins which accompany these arteries converge to-
wards the fossa ovalis and join the great saphenous vein before
it pierces the fascia cribrosa.



228



THE INFERIOR EXTREMITY



Lymph Glands and Vessels. The disposition of the super-
ficial subinguinal lymph glands into two groups will now be
evident a proximal subinguinal group along the line of the
inguinal ligament, immediately distal to the attachment of



Cut edge of Scarpa's fascia
Lumbo-inguinal nerve
Femoral vessels

Superior horn of falciform margin

Subcutaneous inguinal ring
Pectineal part of fascia lata

Spermatic funiculus I
Superficial external |
pudendal artery



Superficial epigastric
rtery

Superficial circum-
flex iliac artery
Lymph gland

iac portion of
fascia lata

Lateral cutane-
ous nerve of the
thigh




Inferior horn of falciform

margin of fossa ovalis

Great saphenous



Two divisions of anterior /'
branch of the medial <
cutaneous nerve (O.T. ^
internal cutaneous)



FIG. 106. Superficial Dissection of the Proximal Part of the Front of the
Thigh. The fossa ovalis (O.T. saphenous opening), the superficial lymph
glands and vessels of the groin are displayed. The lymph vessels may
be recognised by their beaded appearance.

Scarpa's fascia to the fascia lata, and a distal group, which
extends for a short distance distally along the line of the
great saphenous vein. Both groups are separable into medial
and lateral parts.

In a spare subject, or, better still, in a dropsical subject, the



THE THIGH 229

general arrangement of the lymph vessels may also be made
out. To the subinguinal group of glands proceed the super-
ficial lymph vessels of the lower extremity, and lymph vessels
from the external genitals, the perineum, and the lower part
of the abdominal wall. These are termed the afferent vessels.
In addition to them, numerous other vessels connect the
glands with one another. The lymph vessels which lead the
lymph away from the glands are called the efferent vessels. A
large number of them pass through the fossa ovalis, others
pierce the fascia lata. They join the deep subinguinal glands
and the external iliac glands, which lie in relation to the
femoral and external iliac arteries (Figs. 159, 160).

Fossa Ovalis. The fossa ovalis is an aperture in the deep
fascia of the thigh, through which the great saphenous vein
passes before it pierces the femoral sheath and joins the
femoral vein. The fossa lies in the upper and medial angle
of the front of the thigh, its centre being situated about
37 mm. lateral and distal to the pubic tubercle (Fig. 106).
It is bounded, laterally, by a thin curved margin, the margo
faldformis. The margo falciformis is the medial margin of the
more lateral portion of the fascia lata, which, because it is
attached to the inguinal ligament superficial to the iliacus
muscle, and the anterior part of the iliac crest, is called the
iliac part of the fascia lata. The proximal end of the margo
falciformis is the superior cornu (Fig. 106). It turns medially



Online LibraryD. J. (Daniel John) CunninghamCunningham's manual of practical anatomy (Volume 1) → online text (page 23 of 44)