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The superficial veins of the lower limb (Fig. 43.1)
is assisted upwards against gravitational forces by muscular contrac-
The superficial system comprises the great and small saphenous veins.
tion during exercise. Failure of this ‘muscle pump’ to work efficiently,
These are of utmost clinical importance as they are predisposed
as occurs, for instance, during long flights in cramped conditions, may
towards becoming varicose and consequently often require surgery. posterior compartment of the calfathe soleal plexus from which blood
They are also the commonly used conduits for coronary artery surgery. cause deep venous thrombosis (DVT).
• The great saphenous vein arises from the medial end of the dorsal
venous network on the foot. It passes anterior to the medial malleolus, Varicose veins
along the anteromedial aspect of the calf (with the saphenous nerve), These are classified as:
migrates posteriorly to a handbreadth behind patella at the knee and • Primary: due to inherent valve dysfunction.
then courses forward to ascend the anteromedial thigh. It pierces the • Secondary: due to impedance of flow within the deep venous circula-
cribriform fascia to drain into the femoral vein at the saphenous open- tion. These can occur in pregnancy or due to obstruction caused by
ing. The terminal part of the great saphenous vein usually receives pelvic tumours or previous deep venous thrombosis.
superficial tributaries from the external genitalia and the lower abdom- In both cases the superficial veins are subjected to increased pres-
inal wall (Fig. 43.2). At surgery these help to distinguish the saphenous sure and become varicose.
from the femoral vein as the only tributary draining into the latter is the
saphenous vein. Anteromedial and posterolateral femoral (lateral The lymphatics of the lower limb (Fig. 43.1)
accessory) tributaries, from the medial and lateral aspects of the thigh, The lymph nodes of the groin are arranged into superficial and deep
also sometimes drain into the great saphenous vein below the saphen- groups. The superficial inguinal group lie in the superficial fascia and
ous opening. are arranged in two chains:
The great saphenous vein is connected to the deep venous system at • Longitudinal chain: these lie along the terminal portion of the saphen-
multiple levels by perforating veins. These usually occur above and ous vein. They receive lymph from the majority of the superficial tis-
below the medial malleolus, in the gaiter area, in the mid-calf region, sues of the lower limb.
below the knee and one long connection in the lower thigh. The valves • Horizontal chain: these lie parallel to the inguinal ligament. They
in the perforators are directed inwards so that blood flows from receive lymph from the superficial tissues of the: lower trunk below the
superficial to deep systems from where it can be pumped upwards level of the umbilicus, the buttock, the external genitalia and the lower
assisted by the muscular contractions of the calf muscles. The deep sys- half of the anal canal. The superficial nodes drain into the deep nodes
tem is consequently at higher pressure than the superficial and thus, through the saphenous opening in the deep fascia.
should the valves in the perforators become incompetent, the increased The deep inguinal nodes are situated medial to the femoral vein.
pressure is transmitted to the superficial system and these veins become They are usually three in number. These nodes receive lymph from all
varicose. of the tissues deep to the fascia lata of the lower limb. In addition they
• The small saphenous vein arises from the lateral end of the dorsal also receive lymph from the skin and superficial tissues of the heel and
venous network on the foot. It passes behind the lateral malleolus and lateral aspect of the foot by way of the popliteal nodes. The deep nodes
over the back of the calf to pierce the deep fascia in an inconstant posi- convey lymph to external iliac and thence to the para-aortic nodes.
tion to drain into the popliteal vein. Obstruction of lymphatics results in lymphoedema (Fig. 43.3). This
can be congenital, due to aberrant lymphatic formation, or acquired
The deep veins of the lower limb such as post radiotherapy or following certain infections. In develop-
The deep veins of the calf are the venae comitantes of the anterior and ing countries infection with Filaria bancrofti is a significant cause of
posterior tibial arteries which go on to become the popliteal and lymphoedema that can progress to massive proportions requiring limb
femoral veins. The deep veins form an extensive network within the reduction or even amputation.

The veins and lymphatics of the lower limb 97