There are several potential causes of swollen legs and ankles. Some causes, such as standing or walking for long periods, are normal and generally harmless. However, sudden or chronic swelling in the legs and ankles may indicate an underlying health condition.
If you’ve begun to notice an abnormal amount of swelling in your legs and ankles, you may want to schedule an appointment with your primary care physician. Swollen legs and ankles along with red blotchy skin can occur for a variety of reasons, but several may require examination and treatment.
What Is Swollen Legs?
Leg swelling is a sign of fluid buildup or inflammation of the tissues or joints of the leg. Swelling can occur anywhere along the leg, including the thighs, knees, calves, ankles and feet. Mild swelling is a common occurrence after standing for a long time, especially in warm weather.
Leg swelling, which is also called edema, can result from serious infections, trauma, circulatory disorders, cardiac (heart) disorders, and other abnormal processes.
The influence of gravity on human anatomy affects the lower extremities differently than the upper extremities. Extreme leg swelling caused by poor circulation may appear minimal (or absent) in the arms. For the same reason, minimizing the amount of time spent standing and maximizing time reclining can often alleviate this type of leg swelling.
Depending on the cause, leg swelling can last for a short time and disappear quickly, such as when it occurs after standing for a long time or sitting during a long airline flight. Chronic leg swelling, or leg swelling that builds up over time, often indicates a potentially serious disorder, such as congestive heart failure or cardiovascular disease. Leg swelling can also be caused by orthopedic conditions, such as a bone fracture or a cast that is too tight.
Leg swelling generally occurs because of an abnormal accumulation of fluid in the tissues of the lower extremity. The medical term for leg swelling from excessive fluid in the tissues is peripheral edema. Persisting indentation of a swollen leg after pressure from a finger is known as pitting edema. Common causes of leg swelling include salt retention, cellulitis, congestive heart failure, venous insufficiency, pregnancy, and medication side effects.
Less common causes of leg swelling include blood clots in the leg (deep vein thrombosis), parasite infection, lymphedema, liver disease and cirrhosis, kidney disease and nephrotic syndrome, broken ankle, broken leg, and diseases that cause thickness of the layers of skin, such as scleroderma and eosinophilic fasciitis. In these diseases, the leg swelling is typically characterized by nonpitting edema. When leg swelling occurs for unknown reasons, it is referred to as idiopathic edema.
Symptoms that can be associated with leg swelling include
- leg pain,
- shortness of breath, and
- ulceration of the skin.
Having ‘swollen legs’ is a symptom itself, but legs can be swollen in different ways. The clue to the cause (and therefore the treatment) may well be in the type of swelling. The swelling can be:
- One-sided or both-sided. Oedema due to conditions of general body systems is usually on both sides and is symmetrical (for example, if due to heart failure or pregnancy or kidney problems.) One-sided swelling is more likely to be due to a problem with a particular part of that leg.
- In a specific area or generalised. Swelling around joints is usually caused by injury or a type of arthritis. Swelling in specific areas of skin may be caused by allergy or infection. Swelling around the back of the heel suggests a problem of the Achilles tendon, etc. Generalised swelling, especially if on both sides, is likely to be oedema.
- Painful or painless. Painful conditions include infections, deep vein thrombosis (DVT), injuries and joint problems. Oedema is not usually painful, although legs can ache and feel tight.
- Accompanied by red (inflamed) or normal skin colour. If the skin is reddened, it is likely to be due to an infection (such as cellulitis), or inflammation (for example, gout, rheumatoid arthritis or DVT).
- Pitting or not. Pitting means that if you press a fingertip into the swollen area and then take your fingertip away, a dent remains in the skin. (See photo earlier in leaflet.) Oedema tends to be pitting. Lymphoedema, a condition where there is a blockage to lymph fluid, does not usually pit so much.
Causes of Swollen Legs
The most common cause of swelling in both legs is oedema. This is a collection of fluid in between the cells, which are the building blocks of the tissues of our body. Oedema can occur in one particular part of the body, or it can be generalised. If generalised, gravity takes the fluid to the part of you which is hanging down, or ‘dependent’. This type may be called ‘dependent oedema’ by a healthcare professional. For most people, this oedema affects their legs and tends to improve overnight after you have had your legs up. See the separate leaflet called Oedema (Swelling).
If both legs are swollen to the same level, this is likely to be oedema. Causes of oedema affecting both legs symmetrically include:
- Heat. Some people will find their legs swell up a little in hot weather. Usually this is nothing to worry about and does not need treatment.
- Long journeys or being immobile for other reasons. If your legs are hanging down and not moving for long periods of time, you can develop swollen legs. This improves once you are walking about again, or once you lie down at night. This happens because your muscles are not working to move the blood in your blood vessels around. This means the blood pools in the bits of you which are hanging down, putting pressure on the blood vessels and forcing fluid out into the spaces between them. To avoid this, get up and walk around regularly if possible. If not, move your feet and legs around as much as you can.
- Pregnancy. Pregnant women may have swollen legs in late pregnancy. Usually this is par for the course and nothing to worry about, but if you are pregnant, your midwife will be doing regular checks to be sure you don’t have a blood pressure problem (pre-eclampsia) causing it.
- Heart failure. If you have this condition, your heart is not working as effectively to push the blood around your circulation. You may also feel out of breath, and this can be worse when lying down flat at night or on walking.
- Anaemia. This is a problem with the red blood cells of your body.
- Kidney diseases such as nephrotic syndrome, acute kidney injury and chronic kidney disease.
- Conditions where there are low levels of protein. If there are low levels of protein in the blood, less fluid is drawn into the blood from the surrounding areas. Conditions causing low protein levels include malnutrition, nephrotic syndrome, liver failure, and a gut condition called protein-losing enteropathy.
- Side-effects of medicines such as calcium-channel blockers.
- Having very low thyroid levels (hypothyroidism). This is normally accompanied by other symptoms such as tiredness and gaining weight.
- Idiopathic oedema. This means there is oedema but no specific cause has been found for it.
Questions For Diagnosing The Cause Of Leg Swelling
To diagnose the underlying cause of leg swelling, your doctor or licensed health care practitioner will ask you several questions related to your symptoms. You can best help your health care practitioner in diagnosing the underlying cause of leg swelling by providing complete answers to these questions:
- Have you experienced a recent animal or insect bite?
- Have you recently traveled outside the United States?
- What is the exact location of the swelling?
- Describe the swelling. When did the swelling start? Does it come and go or is it constant?
- Are any other body areas swelling?
- Are you are experiencing any pain, shortness of breath, or other symptoms?
- Provide your full medical history, including all medical conditions, surgeries and treatments, family history, and a complete list of the medications and dietary supplements that you take.
How to Reduce Swollen Legs
You may think swollen legs do not require a visit to the doctor. However, leg swelling could be a sign of a serious problem and may often be related to vein disease. Obtaining an expert evaluation of your veins is a logical step. A vein specialist can determine whether vein disease is the cause and the best-swollen leg treatment for you.
Quite often, non-vein specialist physicians may order a standard venous ultrasound. This is to rule out blood clots or deep vein thrombosis (DVT). This type of ultrasound does not always evaluate the one-way valves in leg veins to see if they are operating as they should. Checking your venous system for possible clots is very important. The problem is standard venous ultrasounds for DVT often miss the underlying cause of swollen legs: venous insufficiency. As a result, your initial clinical evaluation could result in a “normal” diagnosis or a “negative clot” result. You may need a more specialized ultrasound to rule out venous insufficiency as the underlying problem.
When to See a Doctor for Swollen Legs
Occasional swelling in your legs may not be a cause for concern. If it becomes an issue that cannot be controlled through lifestyle changes, it’s time to see a doctor. If you develop blisters or sores in the swollen areas, these are also signs you need an evaluation.
Swelling only on one side is perhaps the most worrisome sign you should seek expert vein care. One-sided swelling may indicate a blood clot or DVT, which, if untreated, can cause further issues for your health. A vein expert like Dr. Magnant will evaluate your symptoms. He can also look at your physical signs, discuss your medical history, and recommend a swollen leg treatment plan.
Steps to Prevent Swollen Legs
If you do experience symptoms of edema, make an appointment with your primary care physician before attempting any treatment. Your doctor may make the following recommendations:
Get more comfortable
Wearing more loose-fitting clothing and shoes can help ease swelling. Additionally, try to avoid being in the same position all day, in other words, don’t be on your feet all day and don’t sit all day. When laying down, elevate your feet with a pillow.
Your doctor may also recommend light exercise to help improve your leg circulation. This can include walking, stretching or bicycling. However, you may not be advised to walk or stand too much.
Avoiding salty and high-fat foods such as bacon, chips or french fries can help lower your risk of high blood pressure.
Support stockings help to support your veins and muscles in the lower legs, thus assisting with your lower leg circulation. You should put the stockings on first thing in the morning before your legs start to swell.