Definition
Swollen legs can occur on one or both sides. There can be different causes and the therapy varies depending on the causes.
Causes for swollen legs
There are several possible causes for swollen legs. Often, a weak heart (heart failure) is responsible for leg swelling. The leg swelling in heart failure is caused by the accumulation of water (= oedema) in the legs.
This is called cardiac oedema. The water retention occurs because the heart no longer has enough strength to transport the blood volume sufficiently, resulting in a backlog. Heart failure can also lead to a build-up of fluid in the lungs, which can lead to shortness of breath and a bubbling sound when breathing.
Another cause of leg swelling is thrombosis. If a thrombosis is present, usually only one of the two legs is affected. The leg is often painful and shiny more than the other.
A thrombosis occurs when a blood clot moves a venous vessel in the leg, which leads to a blood accumulation. Lymphedema is also a relatively common cause of leg swelling. The swelling usually occurs on both sides, but can also be localized on one side.
In lymphedema, there is insufficient transport of lymph fluid from the legs to the lymphatic stations located further up the leg. The swelling often begins in the area of the foot, or more precisely the toes, this is indicated by the fact that the skin can no longer be “lifted” off the toes. A venous weakness of the legs can also lead to swelling of one or both legs.
Frequently, additional bluish-lilac skin discolorations can be seen here. Another cause of leg swelling can be medication. In this case, drugs from the group of calcium antagonists which can cause lower leg edema are particularly suitable.
The swelling of the legs is then usually reversible after stopping the medication, i.e. it disappears again. Another possible cause of unilateral leg swelling is erysipelas. A bacterial infection causes the leg to become infected.
This manifests itself in a swelling and severe redness of the leg. The leg is also usually clearly overheated, the redness is usually sharply limited. Lipedema can also lead to swelling of the legs.
A leg swelling that is accompanied by overheating of the leg can also have various causes. In the case of erysipelas, the leg is usually significantly warmer than the opposite side. This is due to the inflammation underlying the swelling.
A thrombosis can also be accompanied by overheating of the affected leg section. If unilateral leg swelling occurs after a long flight, this may be an indication of a thrombosis. If such a thrombosis exists, the affected persons usually complain of additional pain in the affected leg and a feeling of tension.
A long journey with a predominantly sitting position is generally considered a risk factor for the development of thrombosis. Like air travel, an operation or the condition after an operation is a risk factor for the development of a thrombosis. This is due to immobilization (lack of physical activity) after the operation.
If immobilization lasts for several days, the risk of thrombosis is generally increased. For this reason, a blood thinning agent is usually injected under the skin once a day after surgery. This serves to avoid thrombosis. Patients who are initially not allowed to put full weight on one of their legs after an operation (for example, because it has been operated on) are also usually treated with blood thinning agents until they can put full weight on the leg again.
