Most venous disorders occur in the lower limb. Here the superficial veins are prone to cosmetically unsatisfactory, dilated tortuous (varicose) veins, and the deep veins are a common site of thrombosis, following inactivity, as with postoperative state, and in pregnancy, autoimmune disorders and malignancy. Figure 94 is a normal venogram, and figure 95 demonstrates a vein using ultrasound. Complications of thrombosis are swelling (which in extremes cases may produce venous gangrene) and pulmonary emboli. Late sequelae are secondary varicose veins and leg ulceration (figure 96). (See table 2 for the differential diagnosis of leg ulceration, and table 3 (page 262) for the causes of a swollen leg.)
Superficial venous thrombosis (thrombophlebitis migrans; over the breast, this is termed Mondor’s disease) is usually a manifestation of deep malignancy that may be difficult to locate. It also occurs after local trauma.
Table 2 Leg Ulcers
|VASCULAR||NEURO- PATHY||HAEMATO- LOGICAL||MALIG- NANCIES||MISCELL- ANEOUS|
|Primary and Secondary venous insufficiency||Diabetes mellitus||Sickle Cell disease||Kaposi’s sarcoma||Infection|
|Arterial obstructive disease||Alcohol||Leukemia||Melanoma||Syphilis|
|Arteriovenous malformations||Syringomyelia||Hemolytic jaundice||Basal Cell carcinoma||Tropical Pyoderma gangrenosa|
|Note: flat sloping (venous, septic, often with transparent healing edge along part of its circumference); punched out (syphilitic, trophic, diabetic, leprosy, ischemic); undermined (tuberculous, pressure necrosis, particularly over the buttocks, carbuncles); raised (rodent ulcer, often a slightly rolled appearance); raised and everted (carcinoma)|
Varicose veins are usually assessed with a hand held Doppler instrument, but a good deal of information can be obtained from clinical examination. Palpation of the lower leg can often define the sites where large perforating veins have produced palpable defects in the deep fascia (figure 97a). The normal impulse felt proximally along a vein, following a distal tap, may also be felt passing distally, through defective valves (figure 97b); there is usually a cough impulse demonstrating incompetence at the saphenofemoral junction (figure 97c).
Place a venous tourniquet (i.e. occluding the superficial but not the deep veins or arterial flow) around a leg sequentially from above downwards (after first emptying the superficial veins by raising the leg above the horizontal), and ask the patient to stand up (figure 98a–d). This technique can be used to define the level of greatest leakage from the deep to the superficial system (Trendelenburg test).
Place a venous tourniquet below the knee in a patient with varicose veins, and ask them to stand on their toes ten times (Perthe’s test – figure 99). This is usually sufficient for the muscle pump to empty engorged superficial veins into the deep system. However, if there is gross incompetence or thrombosis in the deep system, emptying is prevented: the superficial veins become more rather than less engorged with activity.