Lower extremity lymphedema, also called rubbery swelling, is an obstruction of lymphatic fluid return lymphocyte movement, causing enlarged lymph nodes and dilated lymphatic vessels edema.
Causes of lymphedema of the lower extremities
The causes of the onset of lymphedema of the lower extremities can be divided into two main categories.
(i) Primary lymphedema.
It is caused by abnormal development of lymphatic vessels, most of which are dysplastic, and a few are enlarged by abnormal proliferation of lymphatic vessels.
(ii) Secondary lymphedema.
①Infection causing lymphatic vessel obstruction, such as streptococcal infection, filarial infection, etc.
②Lymphedema caused by radiation therapy and lymph node dissection of cancer or lymphedema caused by tumor compression.
③Lymphedema caused by malignant tumor blocking lymphatic vessels. Primary malignant tumors of the lymphatic system are seen in lymphoma, Kaposi’s tumor and lymphangioleiomyosarcoma. Secondary malignant tumors of the lymphatic system are metastases from malignant tumors of other organs. Sometimes the primary foci are small and not easily detected. The clinical presentation is chronic, painless, progressive lymphedema. Therefore, for lymphedema of unknown cause, the possibility of tumor should be alerted, and if necessary, lymph node biopsy should be performed to clarify the diagnosis.
④Other: systemic diseases (such as pneumonia, influenza, typhoid, etc.), pregnancy, etc.
Clinical manifestations of lower limb lymphedema
The main manifestation is swelling of one limb, starting at the ankle and later involving the whole lower limb. In the early stage, protein-rich lymphatic fluid accumulates in the tissue interstitial space, forming depressed edema, and the skin is still normal. In the late stage, it is due to the concentration of protein accumulated in the tissue interstitium, inflammation and fibrosis of the subcutaneous tissue. As a result, the edema is non-depressed, the skin is thickened, dry, rough, hyperpigmented, and warts or spines appear. The degree of lymphedema can be divided into.
①Mild: the limb edema is depressed and may subside or disappear after elevating the limb, and the skin has no fibrosis-like damage.
②Moderate: the edema is no longer depressed, and the edema does not subside significantly when the limb is elevated, and the skin has moderate fibrosis.
③Severe: elephantiasis-like skin changes appear, and secondary lymphedema often has recurrent lymphangitis and gradually worsening lymphedema. Lymphangitis attacks with local redness, pain, and swollen lymph nodes with pressure pain, often accompanied by sudden chills and high fever.
Examination and diagnosis of lymphedema of the lower extremities
Late stage lower limb lymphedema has typical elephant skin leg characteristics, and the diagnosis is not difficult. Since there are more diseases that can cause lower limb swelling, such as deep vein thrombosis, angioneurotic edema, arteriovenous fistula, etc., but all the above diseases have their own history and manifestations, the differential diagnosis is generally easier. For those with unknown causes of lower limb swelling, in order to exclude or distinguish the causes of lymphatic lesions, radionuclide lymphadenography and lymphadenography can be performed in patients, and the latter has two types of direct and indirect methods: the direct minute method is to inject melanin subcutaneously from the toe webs to make the lymphatic vessels show, and to inject iodine-containing contrast agent by direct puncture after exposure through superficial skin incision; the indirect method is to inject absorbable contrast agent intradermally in the edematous area, and then film is taken.
Prevention and prescription treatment of lower limb lymphedema
1. Active treatment of the primary disease. For lymphangitis caused by Streptococcus haemolyticus infection, the patient should be treated thoroughly at the first episode, with adequate dosage of antibiotics and an appropriately prolonged course of treatment. Tinea pedis is a common factor in the invasion of pathogenic bacteria and should be treated with antimycobacterial therapy.
2. Skin care, prevention of infection, injury. A certain amount of exercise.
3 Non-surgical temporary therapy: including elevation of the affected limb, wearing elastic stockings, limiting water and salt intake, using diuretics, preventing infection, and baking therapy. Baking therapy has two kinds of electric radiation heat treatment device and oven method, the temperature is generally adjusted between 80 to 100 ℃, once a day, each time 1 hour, 20 times for a course of treatment, while using elastic bandage will be the affected limb pressure bandage, each course of treatment 1-2 months apart, generally after 1-2 courses of treatment, the affected limb tissue softening, limb After 1-2 courses of treatment, the tissues of the affected limb will be softened, the limb will be gradually shrunken, and the dermatomycosis-like attacks will be significantly reduced. Through repeated thermal effect stimulation, the local tissue metabolic activity is strengthened, and the regeneration of lymphatic vessels and the recovery of lymphatic reflux are promoted.
4.Surgical therapy: There are four kinds of surgical therapies currently applied as follows.
① Total subcutaneous excision and implantation;
②Dermal flap embedding;
(iii) Tendonoplasty with large omentum graft;
④Lymphovascular-venous anastomosis or lymph node-venous anastomosis.