Anatomy of the lower extremity veins – varicose veins top universities for nursing

Thorough knowledge of the fascial compartments of the leg is a prerequisite of understanding the relationship between superficial and deep veins. Top universities for psychology the fascia surrounding the calf and thigh muscles separates two compartments: the superficial compartment, consisting of all tissues between the skin and the fascia, and the deep compartment, which includes all tissues between the fascia and the bones (see figure 2.6).11 superficial veins run in the superfical, deep veins in the deep compartments. Perforating veins pierce through the fascia and connect the superficial to deep veins.12 communicating veins connect veins within the same compartment: superficial to superficial or deep to deep veins. The saphenous veins are covered by a fibrous sheath, the saphenous fascia. The saphenous fascia is thinner than the deep fascia and it is more pronounced in the upper-mid thigh, than more distally.113 the space between the saphe-nous and muscular deep fascia is the saphenous compartment.

The saphenous compartment is a subcompartment of the superficial compartment.

The superficial venous system of the foot is divided into the dorsal and plantar subcutaneous venous network (see figure 2.7). Superficial vein tributaries drain blood into the dorsal venous arch on the dorsum of the foot at the level of the proximal head of the metatarsal bones. The medial and lateral end of this arch continues through the medial and FIGURE 2.7 superficial and perforating veins of the foot and ankle.

Small superficial veins drain the subpapillary and reticular plexuses of the skin and subcutaneous tissues to form bigger tributaries, which eventually all connect to the saphenous veins.1415 the GSV begins just anterior to the medial ankle, crosses in front of the tibia, and ascends medial to the knee (see figure 2.8).16-18 proximal to the knee, the GSV ascends on the medial side of the thigh and enters the fossa ovalis 3 cm inferior and 3 cm lateral to the pubic tubercle.19 the GSV is doubled in the calf in 25% of the population, in the thigh in 8%.20 the saphenous nerve runs in close proximity to the GSV in the distal two-thirds of the calf. Accessory great saphenous veins are frequently present and they run parallel to the GSV both in the thigh and in the leg; they lie either anterior, posterior, or superficial to the main trunk. The posterior accessory GSV of the leg (leonardo’s vein or posterior arch vein) is a common tributary, it begins posterior to the medial malleolus, ascends on the posteromedial aspect of the calf, and joins the GSV distal to the knee (see figure 2.8). The anterior accessory GSV of the leg drains the anterior aspect of the leg below the knee. The posterior accessory GCV of the thigh, if present, drains the medial and posterior thigh.11 the anterior accessory GSV of the thigh collects blood from the anterior and lateral side of the thigh (see figure 2.8). The anterior and posterior accessory gsvs join the GSV just before it ends at the confluence of superficial inguinal veins (saphenofemoral junction). The superficial circumflex iliac, superficial epigastric, and exter-

Nal pudendal veins join each other and the distal GSV to form the confluence of superficial inguinal veins (sapheno-femoral junction) (see figure 2.9).21 rarely, the GSV terminates high on the lower abdomen or joins the femoral vein very low and the superficial inguinal veins empty individually into the femoral vein.22 other occasional tributaries of the GSV in the groin include the posterior and anterior thigh circumflex veins.

The small saphenous vein (SSV) lies lateral to the achilles tendon in the distal calf (see figure 2.10).23 in the lower two-thirds of the calf the SSV runs in the subcutaneous fat, then it pierces the fascia and runs between the two heads of the gastrocnemius muscle. In the popliteal fossa at about 5 cm proximal to the knee crease, the main trunk of the SSV drains into the popliteal vein. A smaller vein, the cranial extension of the SSV, frequently continues in ceph-alad direction (see figure 2.10).24 uncommonly the main trunk of the SSV continues without draining into the popliteal vein and eventually empties into the femoral vein or GSV.11 the intersaphenous vein (vein of giacomini) is a communicating vein connecting the SSV to the GSV in the

Posterior-medial thigh. The sural nerve courses along the SSV in the distal calf. Superficial veins of the lateral leg and thigh form the lateral venous system. The lateral venous system is drained through multiple small tributaries into the GSV and SSV.

Deep veins of the foot form two divisions: the plantar and the dorsal veins. The richly anastomosing deep plantar venous arch drains the plantar digital veins through the plantar metatarsal veins. University rankings in usa the deep plantar venous arch drains into the medial and lateral plantar veins, which in turn continue in the posterior tibial veins behind the medial ankle (see figure 2.11).25 on the dorsum of the foot the pedal vein drains the deep dorsal digital veins through the dorsal meta-tarsal veins. The pedal vein continues in the anterior tibial veins. Pairs of the posterior and anterior tibial and peroneal veins accompany the corresponding arteries, and all drain into the popliteal vein (see figures 2.11 and 2.12). Large soleal and gastrocnemius (medial, lateral, and intergemellar) veins drain venous sinuses of calf muscles and join the popliteal vein. Venous sinuses are closely related to deep veins. They are embedded in the belly of calf muscles, such as the soleus and gastrocnemius, and are able to dilate and hold a large amount of blood. With the contraction of calf muscles at walking the blood is pumped to more proximal deep veins (calf muscle pump). The popliteal vein continues into the femoral vein as it is passing through the adductor FIGURE 2.12 deep veins of the leg.

Canal. The popliteal and femoral veins are frequently duplicated.26 distally the femoral vein runs lateral to the femoral artery; however, more proximally it runs medial to it. The deep femoral (profunda femoris) vein joins the femoral vein to form the common femoral vein at about 9 cm below the inguinal ligament.27 the common femoral vein is medial to the common femoral artery and it becomes the external iliac vein at the level of the inguinal ligament. The GSV joins the common femoral vein at the confluence of the superficial inguinal veins. Other tributaries of the common femoral vein are the circumflex femoral veins (lateral and medial). In the distal thigh the femoro-popliteal segment frequently communicates through a large collateral with the deep femoral vein providing an important alternative avenue for venous drainage in case of femoral vein occlusion. The sciatic vein, the main trunk of the primordial deep venous system, runs along the sciatic nerve.

There are as much as 150 perforating veins (pvs) in the lower extremity; however, only a few of these are clinically important. Significant variation exists in the location of individual pvs; however, distribution of clusters of pvs follows a predictable pattern. Dorsal, plantar, medial, and lateral foot perforators are the main groups of pvs in the foot.28 A large PV runs between the first and second metatarsal bones and connects the superficial dorsal venous arch to the pedal vein.29 clusters of pvs at the ankle are the anterior, medial, and lateral ankle perforators (see figure 2.13).30 the medial calf perforators have two groups: posterior tibial and para-tibial pvs. Three groups (lower, middle, upper) of posterior tibial pvs (cockett I-III perforators) connect the posterior accessory GSV to the posterior tibial veins (see figures 2.8, 2.11, and 2.13).31,32 the paratibial perforators drain the GSV FIGURE 2.13 relationship of the posterior tibial perforators to the deep and superficial posterior compartments (SPC) of the calf (ptvs, posterior tibial veins).

Into the posterior tibial veins.33,34 other perforators of the leg below the knee are the anterior, lateral, medial, and lateral gastrocnemius; intergemellar and achillean pvs (see figure 2.11). Best universities in texas infra- and suprapatellar and popliteal fossa pvs are located around the knee. Perforators of the femoral canal connect tributaries of the GSV to the femoral vein (see figure 2.8). Inguinal perforators drain into the femoral vein in the proximal thigh.

Valves in superficial veins of the lower extremity usually are located near to the termination of major tributaries. Some valves are well developed with marked sinusoid dilation at their base, others are more delicate in their structure. In the GSV there are about six valves, with more valves located below than above the knee. A nearly constant valve of GSV is at 2-3 cm distal to its confluence with the femoral vein. Top university ranking valves in the SSV are closer to each other than in the GSV. Valves in communicating branches between the SSV and GSV are oriented to direct blood from the small to the great saphenous vein. Similar to superficial veins, deep veins have more valves in the calf than in the thigh. Tibial veins are densely packed with valves, whereas there are only one or two valves in the popliteal vein. In the femoral vein there are three to five valves, with one of them located just distal to the junction of the deep femoral vein. There is usually one valve in the common femoral vein. Major pvs have one to three valves, all located below the level of the fascia, that direct flow toward the deep veins. Small pvs are usually valveless. PVs of the foot are without any valves or with valves that direct flow toward the superficial veins.

2. Caggiati A, bergan JJ, gloviczki P, jantet G, wendell-smith CP, partsch H. International interdisciplinary consensus committee on venous anatomical terminology. Nomenclature of the veins of the lower limbs: an international interdisciplinary consensus statement, journal of vascular surgery. 2002. 36(2): 416-422.