Swelling (oedema) of the lower legs and feet happens when fluid in the lower legs has difficulty returning back up to the heart. There are many things that can cause this but in every case of chronic oedema you will find that lymphatic drainage is impaired in some way. This damage can be caused by two things: an underlying abnormality (‘primary’ or ‘secondary’) of the lymphatic system; or by the lymphatics being overloaded by a high lymph load, which results in ‘lymphatic failure’
Causes of swollen legs and feet / oedema
Venous hypertension / insufficiency
Swelling in the lower legs is often caused by problems with the veins in the lower legs. Blood is pumped from the heart to the rest of the body through arteries and returns through the veins. The blood is propelled back to the heart by the heart pumping and by being pushed by the leg and foot muscles during walking and ankle movement.
The veins contain one-way valves to stop back flow or the blood falling back towards the toes. These valves can become weak or damaged, which causes venous back flow. It’s this back flow which leads to venous hypertension and / or varicose veins.
What does oedema look like?
People’s legs and feet can also swell if there are problems with the lymphatic system. The lymphatic system can be thought of as a waste disposal system that takes tissue fluid and waste products away from the tissues around the skin, fat, muscle and bone. Once inside the lymphatic vessels (which initially are barely visible just under the surface of the skin), the tissue fluid becomes known as ‘lymph’ and is transported in one direction by increasingly larger and deeper lymphatic vessels. Collection of fluid and waste products from the tissue spaces by the lymphatic capillaries is entirely dependent on movement of surrounding tissues. Not having a pump like the heart to propel movement of lymph, the lymphatic system depends on muscle activity and deep breathing to work well and to reduce lymphatic swelling. Therefore being active is essential for a healthy lymphatic system and is a key part of Lymphoedema management.
You can read more about lympoedema on the information pages of the British Lymphology Society and download the leaflet “What is Lymphoedema?” or see a short video about “What is Lymphoedema?” below.
Swelling in the lower legs can also be caused by right-sided congestive heart failure. This is known as cardiac oedema and also causes shortness of breath and weight gain. It is important that you consider cardiac oedema when treating patients presenting with these symptoms, and before you consider compression therapy. However, someone with a cardiac problem may also have other problems, such as lymphoedema which must be treated.
Assessment of a patient with oedema
Effective management of chronic oedema generally involves prompt application of appropriate compression therapy. However it is critical to first carry out a comprehensive assessment of anyone who presents with a chronic (more than 3 months) oedema of their lower legs.
Your assessment should include:
- Possible risk factors for venous insufficiency, arterial disease, lymphoedema
- Exclude lipoedema as a possible diagnosis
- A clinical assessment for significant arterial impairment. This may include, but should not be solely based on, measurement of Ankle Brachial Pressure Index (ABPI), particularly because a reading may not be possible in a swollen limb. Please refer to the Best Practice for ABPI and the British Lymphology Society guidance on Assessing vascular status in the presence of chronic oedema which includes an assessment tool to guide decision making when an ABPI reading is not possible.
- If you suspect that your patient may have problems with their veins or arteries you should refer them for further vascular tests to see if they are suitable for (modified) compression therapy and or intervention to the veins or arteries
If you suspect that your patient has cellulitis an urgent medical referral is required. Please also refer to the BLS consensus guidelines
If your patient has leakage of lymph from their legs, please refer to the Lymphoedema Network Wales Pathway
If your patient appears to have problems with their lymphatic system or you suspect they could have lipoedema, refer them to a lymphoedema service.
Best Practice Statements – Wound Management, Skin Care, Compression, ABPI, Dressings, Lipoedema (PDF Download – Open access – registration required to download)
Doppler ultrasound (Web page)
ABPI (PDF Download)
Chronic Oedema Wet Leg Pathway (Web page with PDF Download)
BLS position paper for assessing vascular status in the presence of chronic oedema (PDF Download)
Treatment of oedema
The treatment of swollen legs depends on what has caused it.
The first line treatment for venous hypertension should be a combination of compression therapy and assessment of need for venous intervention. If there is soft, mild oedema in the presence of an ulcer, a leg ulcer kit may be appropriate.
The key components of treatment are:
Lifestyle changes – give your patients advice on
- How to care for their skin and prevent cellulitis
- Activity, deep breathing, movement and standing/sitting
- How to achieve and maintain a healthy diet and weight
Compression therapy for lymphoedema
This may involve singly, or in combination, bandaging, compression garments or wraps.
Compression garments are usually the mainstay of long term treatment. Generally, higher levels of compression are needed when treating lymphoedema than if treating venous oedema alone (minimum RAL Class 1 (18-23mm Hg).
Flat knit and/or custom made garments are often used. This is because lymphoedema changes the shape of the limb so off-the-shelf garments can create a tourniquet effect, which exacerbates swelling.
Multi-layer lymphoedema compression bandaging (MLB)
Bandaging is an alternative to compression garments. Short-stretch bandaging is generally used to create a low resting pressure and high working pressure. You should consider bandaging if:
- Skin is fragile, damaged or ulcerated skin or there is lymphorrhoea (weeping skin)
- There are chronic skin changes, e.g. hyperkeratosis or papillomatosis
- There is distortion in shape or exaggerated skin folds
- The patient’s limb is too large to fit hosiery
You should apply compression bandaging with caution if the patient has signs of:
- Severe arterial disease
- Untreated deep vein thrombosis (DVT)
- Uncontrolled heart failure
- Uncontrolled hypertension
- Severe peripheral neuropathy
- Cellulitis – compression may be suspended or reduced for a few days if the patient is unable to tolerate normal compression, otherwise, it may be continued.
Wraps may be used as an adjunct to treatment or as an alternative to compression garments or bandaging (as long as there is minimal or well-managed exudate) if the patient is unable to apply stockings, or long term bandaging is not an option.
Manual lymphatic drainage
This is a specialised light massage technique that stimulates and reroutes lymph flow to viable drainage areas
Simple (self or carer-administered) lymphatic drainage
Patients or their carers can be taught a simplified form of lymphatic drainage.
Other adjunctive therapies to consider include sequential pneumatic compression, kinesiotaping or low level laser therapy. These all need to be carried out by practitioners with specialist training.
What information, advice and support should be provided for those at risk of lymphoedema? (Web page with option to download PDF for members)
Lymphoedema facts, activity and exercise (Web page with option to download PDF)
Get moving with lymphoedema (PDF Download)
The main components of lipoedema management are:
- Lifestyle changes, including advice on healthy eating and weight management, physical activity and mobility, and skin care and protection
- Psychosocial support and management of expectations
- Education, including family planning, pregnancy advice and genetic counselling
- Compression therapy, usually under the guidance of a lymphoedema practitioner
- Management of pain
Publications & Evidence for oedema
Click below for resources to help in your everyday work
Patient information for oedema
The patients, family and friends section has lots of useful, accessible information for your patients.
If you need further information or support, we’d recommend the following organisations as trusted partners and reliable sources.
Accelerate We have a clear vision at Accelerate – Our vision is to boldly transform chronic wound and lymphoedema care. And we do this by developing and increasing access to world-class treatments and thinking in chronic wound and lymphoedema care. We're based in East London but can accept national referrals from your GP / specialist to our world-class centre where we pioneer and trial experimental new treatments for chronic wounds, lymphoedema and mobility challenges.
The British Lymphology Society (BLS) is a dynamic and innovative body providing a strong professional voice and support for those involved in the care and treatment of people with lymphoedema and related lymphatic disorders, including lipoedema.
Find out more on the British Lymphology Society website
Lymphoedema Support Network (LSN) is a national UK charity which provides information and support to people with lymphoedema.
020 7351 0990
Find out more on the Lymphoedema Support Network website
Tell us what you think
If there’s anything you want to ask us or tell us, whether it’s a suggestion about our website, a complaint, or a compliment, drop us a line at