Lymphedema is extremity swelling resulting from a reduction in lymphatic transport. Reductions in lymphatic transport may result from a number of anatomic or functional abnormalities, such as dermal lymphatic hypoplasia; acquired stenosis or obliteration of the axial lymphatics; or acquired or congential absence or malfunction of lymphatic valves. The functional result common to all these abnormalities is pooling of lymph within the interstitial space and swelling of the subcutaneous tissues and skin. While most lymphedema of clinical importance to vascular surgeons involves an extremity, lymphedema can affect the skin and subcutaneous tissues anywhere.

The most widely used classification of lymphedema is based on whether there is a known etiology of the lymphedema. There are primary and secondary forms of lymphedema. Primary lymphedema results from an unknown cause. It may have a genetic component of uncertain phenotypic expression. Primary lymphedema is subdivided into congenital lymphedema, lymphedema praecox, and lymphedema tarda.

Congenital lymphedema can involve a single lower extremity, multiple limbs, the genitalia, or the face. The edema is typically present at birth. Milroy’s disease is a form of congenital lymphedema generally affecting the lower extremities. It results from an absence of the dermal lymphatics. The axial lymphatics are normal. The children typically develop lower-extremity swelling shortly after birth that becomes more pronounced with attempted ambulation.

Lymphedema praecox is the most common form of primary lymphedema, accounting for 94% of cases. It is far more common in women than men, with the gender ratio favoring women 10:1. The onset of swelling is during the childhood or teenage years and involves the foot and calf. Lymphedema praecox affects primarily the axial lymphatics with varying combinations of obliteration and reflux of the axial lymphatic vessels. The onset of the lymphedema often follows an injury so trivial that it is difficult to imagine how the injury could have directly resulted in limb swelling. It seems more likely that the minor injuries associated with the onset of lymphedema praecox are circumstantial and not actually related to the onset of the disease. Lymphedema praecox has an uncertain prognosis. It often begins with foot and ankle swelling. The swelling may remain confined to the distal aspect of a single extremity or may progress more proximally. Involvement of the opposite lower extremity and even upper extremities may occur.

Lymphedema tarda is uncommon, accounting for less than 10% of cases of primary lymphedema. The pathophysiology, anatomic abnormalities, and prognosis appear similar to lymphedema praecox except that the onset of the edema is later in life than in lymphedema praecox.

Secondary lymphedema is far more common than primary lymphedema. Secondary lymphedema is a result of acquired lymphatic obstruction or disruption. Lymphedema of the arm following axillary node dissection for treatment of breast cancer is the most common cause of secondary lymphedema in the United States and other developed countries. Other causes of secondary lymphedema include trauma, radiation therapy, or malignancy. World wide, filariasis, which causes elephantiasis, is the most common cause of secondary lymphedema.

The diagnosis of lymphedema is usually based on the combination of the history, physical examination, and the exclusion of other potential causes of limb swelling. Many conditions can cause edema, particularly of the lower extremities. Distinguishing lymphedema from other more common causes of leg swelling is, however, usually not difficult. If the onset of edema is bilateral, the cause of the limb swelling is likely not lymphedema secondary to an anatomic lymphatic abnormality. Bilateral pitting edema is typically associated with congestive heart failure, renal failure, or a hypoproteinemic state. The most common dilemma is to distinguish the swelling of lymphedema from that of venous insufficiency.

Patients with lymphedema and venous disease both commonly complain of fatigue and heaviness of the affected extremity. Lymphedema is usually, but not always, painless. Patients with lymphedema may complain of pain and discomfort but, in general, the pain
component of lymphedema is less than that of chronic venous insufficiency.

In patients with lymphedema, as in those with venous insufficiency, the limb circumference increases throughout the day and decreases overnight when the patient is in bed. The lymphedematous limb, however, rarely completely normalizes even with a prolonged period of bedrest and leg elevation. This is in contrast to swelling secondary to venous insufficiency where the response to bedrest and leg elevation is usually more dramatic.

Lymphedema swelling classically involves the dorsum of the foot. Venous swelling usually does not extend onto the foot. The toes in established lymphedema have a “squaredoff” appearance. There is usually no swelling of the toes in pure venous insufficiency. In advanced lymphedema, usually neglected and inadequately treated cases, hyperkeratosis of the skin develops (Fig. 72-1) and fluid weeps from lymph-filled vesicles. Hyperpigmentation, a hallmark of long-standing venous insufficiency, is not a part of lymphedema. While ulceration can occur with lymphedema, it is very unusual.

Recurrent cellulitis is a common complication of lymphedema. Repeated infection results in further lymphatic damage, worsening existing disease and putting the patient at increased risk of future infection. The clinical presentation of cellulitis ranges from subtle erythema and worsening of edema to a rapidly progressive soft tissue infection with systemic toxicity.

Management of lymphedema is primarily nonoperative and is directed toward maintaining as near-normal limb circumference as possible within the constraints imposed by the disease and necessary activities of daily living.