PARAFERAL VASCULAR DISEASE:

 





Examine both femoral arteries by palpating and then

auscultating them. A bruit may be heard if the artery

is narrowed. Next palpate the following pulses: popliteal

(behind the knee—see Fig. 6.5(a): if this is difficult to

feel when the patient is supine, try the method shown

in Fig. 6.5(b)), posterior tibial (under the medial

malleolus, see Fig. 6.6(a)) and dorsalis pedis (on the

forefoot, Fig. 6.6(b)) on both sides.2

Patients with exertional calf pain (intermittent

claudication) are likely to have disease of the peripheral

arteries. More severe disease can lead to pain even

at rest and to ischaemic changes in the legs and feet

(see Good signs guide 6.1). Look for atrophic skin

and loss of hair, colour changes of the feet (blue or

red) and ulcers at the lower end of the tibia.3 Venous

and diabetic ulcers can be distinguished from arterial

ulcers (see Figs 6.7–6.9).

Look for reduced capillary return (compress the

toenails—the return of the normal red colour is slow).4

In such cases, perform Buerger’sb test to help confirm

your diagnosis: elevate the legs to 45° (pallor is rapid

if there is a poor arterial supply), then place them

dependent at 90° over the edge of the bed (cyanosis

occurs if the arterial supply is impaired). Normally

there is no change in colour in either position.

The ankle–brachial index (ABI) is a measure of

arterial supply to the lower limbs; an abnormal index

indicates increased cardiovascular risk.5 The systolic

blood pressure in the dorsalis pedis or posterior

tibial artery is measured using a Doppler probe and

a blood pressure cuff over the calf. 

DISEASE ChART:


LR = likelihood ratio.

SignLR+LR−

Sores or ulcers on feet5.90.98

Feet pale, red or blue2.30.80

Atrophic skin1.650.72

Absent hair1.60.71

One foot cooler5.90.92

Absent femoral pulse5.80.94

Absent dorsalis pedis or posterior tibial pulse3.70.37

Limb bruit present5.70.58

Capillary refill time >5 seconds1.90.84

Venous refill time >20 seconds3.60.83

ACUTE ARTERIAL OCCLUSION

Acute arterial occlusion of a major peripheral limb

artery results in a painful, pulseless, pale, ‘paralysed’

limb that is perishingly cold and has paraesthesias (the

six Ps). It can be the result of embolism, thrombosis

or injury. Peripheral arterial embolism usually

arises from thrombus in the heart, where it may be

secondary to:

1. atrial fibrillation

2. myocardial infarction

3. dilated cardiomyopathy, or

4. infective endocarditis.

CHAPTER 6 THE lImb ExAmINATION ANd PERIPHERAl vASCulAR dISEASE 115

FIGURE 6.8

Arterial ulcer.

This arterial ulcer has a regular margin and

‘punched out’ appearance. The surrounding

skin is cold. The peripheral pulses are absent.

(See List 6.4.)


(From McDonald FS, ed. Mayo Clinic images in internal medicine,

with permission. © Mayo Clinic Scientific Press and CRC Press.

Reproduced by permission of Taylor and Francis Group, LLC, a

division of Informa plc.)

FIGURE 6.9

diabetic (neuropathic) ulcer.

Neuropathic ulcers are painless and are

associated with reduced sensation in the

surrounding skin.

(From McDonald FS, ed. Mayo Clinic images in internal medicine,

with permission. © Mayo Clinic Scientific Press and CRC Press.

Reproduced by permission of Taylor and Francis Group, LLC, a

division of Informa plc.)

DEEP VENOUS

THROMBOSIS

Deep venous thrombosis (DVT) is a difficult clinical

diagnosis.7 The patient may complain of calf pain. On

examination, the clinician should look for swelling of

the calf and the thigh, and dilated superficial veins.

Feel then for increased warmth and squeeze the calf

(gently) to determine whether the area is tender.

Homans’

c sign (pain in the calf when the foot is sharply

dorsiflexed, i.e. pushed up) is of limited diagnostic value

and is theoretically dangerous because of the possibility

of dislodgement of loose thrombus.

The causes of thrombosis were described by

Virchowd in 1856 under three broad headings (the

famous Virchow’s triad):

1. changes in the vessel wall

2. changes in blood flow

3. changes in the constitution of the blood.

Deep venous thrombosis is usually caused by

prolonged immobilisation (particularly after lower

limb orthopaedic surgery), cardiac failure (stasis)

or trauma (vessel wall damage), but may also result

from neoplasm, sepsis, chronic inflammatory bowel

disease, disseminated intravascular coagulation,

the contraceptive pill, pregnancy and a number of

inherited defects of coagulation (the thrombophilias:

e.g. antithrombin III deficiency or the factor V Leiden

mutation).

VARICOSE VEINS

If a patient complains of ‘varicose veins’, ask him or

her to stand with the legs fully exposed.8 Inspect the

front of the whole leg for tortuous, dilated branches

of the long saphenous vein (below the femoral vein in

the groin to the medial side of the lower leg). Then

inspect the back of the calf for varicosities of the short

saphenous vein (from the back of the calf and lateral

malleolus to the popliteal fossa). Look to see whether

c John Homans (1877–1954), a professor of surgery at Harvard University,

Boston. He described his sign in 1941, originally in cases of thrombophlebitis.

He later became disenchanted with the sign and is reputed to have asked

why if a sign were to be named after him it couldn’t be a useful one.

d Rudolph Virchow (1821–1902), a brilliant German pathologist, regarded

as the founder of modern pathology, professor of pathological anatomy

in Berlin. He provided the first description of leukaemia. He died aged

81 after fracturing his femur jumping from a moving tram.the leg is inflamed, swollen or pigmented (subcutaneous

haemosiderin deposition secondary to venous stasis).

Palpate the veins. Hard leg veins suggest thrombosis,

whereas tenderness indicates thrombophlebitis. Perform

the cough impulse test. Put the fingers over the long

saphenous vein opening in the groin, medial to the

femoral vein. (Do not forget the anatomy—femoral

vein [medial], artery [your landmark], nerve [lateral].)

Ask the patient to cough: a fluid thrill is felt if the

saphenofemoral valve is incompetent.

The following supplementary tests are occasionally

helpful (and surgeons like to quiz students on them

in examinations):

• Trendelenburge test: with the patient lying down,

the leg is elevated. Firm pressure is placed on the

saphenous opening in the groin, and the patient

is instructed to stand. The sign is positive if the

veins stay empty until the groin pressure is

released (incompetence at the saphenofemoral

valve). If the veins fill despite groin pressure, the

incompetent valves are in the thigh or calf, and

Perthes’f test is performed.

• Perthes’ test: repeat the Trendelenburg test, but

when the patient stands, allow some blood to be

released and then get him or her to stand up and

down on the toes a few times. The veins will

become less tense if the perforating calf veins are

patent and have competent valves (the muscle

pump is functioning).

If the pattern of affected veins is unusual (e.g. pubic

varices), try to exclude secondary varicose veins. These

may be due to an intrapelvic neoplasm that has

obstructed deep venous return. Rectal and pelvic

examinations should then be performed.

CHRONIC VENOUS DISEASE

Chronic venous stasis is a common cause of leg oedema.

It is a result of increased pressure in the venous system.

There may be a history of previous deep venous

thrombosis or of varicose veins. These are associated

with incompetence of the valves of the perforating

e Friedrich Trendelenburg (1844–1924), a professor of surgery in Leipzig.

f

Georg Clemens Perthes (1869–1927), a German surgeon and professor

of surgery at Tübingen. He was the first to use radiotherapy for the

treatment of cancer (in 1903).

veins, which connect the deep and superficial veins

of the legs. This can lead to dilation of the upper part

of the long saphenous veins and make their valves

incompetent. Failure of the muscle pump mechanism

that directs blood up the veins can have similar effects. It

is common in elderly inactive patients. Chronic venous

stasis leads to oedema and a rise in tissue pressure,

which causes thinning of skin and subcutaneous tissue.

Skin ulceration and necrosis may occur.

Typically ulcers occur above the medial malleoli.

Eventual healing often has inadequate circulation and

skin will often break down again. The indurated skin

is often stained a purple black colour; this is a result

of staining with haemosiderin from red blood cells

that have been extravasated into the tissues. Chronic

venous eczema may complicate the condition. The legs

appear more swollen and erythematous (Fig. 6.10).

This is often misdiagnosed as cellulitis (skin infection),

but cellulitis is never bilateral.

This chronic oedema is described as brawny. It will

pit only slowly and unwillingly on compression. Signs

of right heart failure (raised JVP and pulsatile liver,

ascites) are absent.


CAUSES OF LEG ULCERS:

1. Venous stasis ulcer—most common

(see Fig. 6.7)

Site: around malleoli

Character: irregular margin, granulation tissue

in the floor. Surrounding tissue inflammation

and oedema

Associated pigmentation, stasis eczema

2. Ischaemic ulcer (see Fig. 6.8)

○ Large-artery disease (atherosclerosis,

thromboangiitis obliterans): usually lateral

side of leg (pulses absent)

○ Small-vessel disease (e.g. leucocytoclastic

vasculitis): palpable purpura

Site: over pressure areas, lateral malleolus,

dorsum and margins of the feet and toes

Character: smooth, rounded, ‘punched out’ pale

base that does not bleed

3. Malignant ulcer, e.g. basal cell carcinoma

(pearly translucent edge), squamous cell

carcinoma (hard everted edge), melanoma,

lymphoma, Kaposi’s sarcoma

4. Infection, e.g. Staphylococcus aureus, syphilitic

gumma, tuberculosis, atypical Mycobacterium,

fungal

5. Neuropathic (painless penetrating ulcer on sole

of foot: peripheral neuropathy, e.g. diabetes

mellitus, tabes [tertiary syphilis], leprosy) (see

Fig. 6.9)

6. Underlying systemic disease

○ Diabetes mellitus: vascular disease,

neuropathy or necrobiosis lipoidica (front of

leg)

○ Pyoderma gangrenosum

○ Rheumatoid arthritis

○ Lymphoma

○ Haemolytic anaemia (small ulcers over

malleoli), e.g. sickle cell anaemia


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