Amputation below knee overview

Overview

A below-knee amputation is surgery to remove the foot and part of the lower leg, but keep the knee joint. It is done when the leg below the knee is severely damaged or diseased and cannot be saved. After healing, most people can use an artificial leg called a prosthesis.

It is not very common in the general population, but it is one of the most common major amputations. In the UK, thousands of people have a below-knee amputation each year, often due to problems with blood flow or diabetes.

It mostly affects older adults, especially those with peripheral artery disease (narrowed leg arteries) or diabetes. It can also happen to younger people after a severe injury or infection.

Symptoms

Common symptoms

• Severe leg pain that does not go away, especially at night
• A leg wound or sore that does not heal after several weeks
• Skin on the leg that turns dark, black, or blue (gangrene)
• Swelling, redness, or foul-smelling discharge from a leg ulcer
• Coldness or numbness in the leg or foot

Symptoms in children

• Caused mainly by traumatic injuries or birth defects
• After surgery, children may experience phantom limb sensations (feeling the missing limb)
• Bone growth at the amputation site may require a second surgery

Symptoms in older adults

• Often related to diabetes, poor circulation, or infection
• Slower wound healing and higher risk of complications
• May need more help with rehabilitation and adapting to a prosthesis

Causes

Main causes

• Peripheral artery disease – narrowed leg arteries that limit blood flow
• Diabetes – high blood sugar can damage nerves and blood vessels, leading to infections and poor healing
• Severe injury – such as crush injuries, burns, or fractures that cannot be repaired
• Infection – serious infections like gangrene or bone infection (osteomyelitis) that do not respond to treatment
• Cancer – tumours in the leg bones or soft tissues that require removal

Risk factors

• Smoking
• Uncontrolled diabetes
• High blood pressure
• High cholesterol
• Being overweight
• Age over 60
• Previous leg ulcers or amputations

When to see a doctor

See a doctor urgently if:

• You have a leg wound that is not healing after 2 weeks of care
• You notice a part of your leg turning black or blue
• Your leg feels cold and has no pulse (can't feel a heartbeat in your foot)

Book a routine appointment if:

• You have leg pain when walking that goes away when you rest (possible sign of narrowed arteries)
• You have diabetes and notice any new sores, blisters, or changes in foot colour
• You have a family history of peripheral artery disease or amputation

Diagnosis

A doctor will ask about your symptoms and medical history, examine your legs, and check the pulses in your feet. They may listen to your leg arteries with a stethoscope and look at skin colour and temperature.

Tests that may be done

• Ankle-brachial index – compares blood pressure in your ankle and arm
• Doppler ultrasound – a scan to see blood flow in your leg arteries
• Angiography – an X-ray with dye to show blockages in arteries
• Blood tests – to check for infection, diabetes, or other conditions
• MRI or CT scan – if cancer or bone infection is suspected

What to expect at your appointment

Your doctor will explain the results and discuss all options. If amputation is recommended, they will explain why and what to expect before, during, and after surgery. You will meet with a surgeon, physiotherapist, and possibly a psychologist to help you prepare.

Treatment

Treatment focuses first on saving your leg if possible. If amputation is needed, the goal is to remove the damaged part and help you regain as much function as possible with a prosthetic limb. Treatment includes wound care, infection control, surgery, rehabilitation, and fitting of an artificial leg.

Self-care at home

• Stop smoking – this is the most important thing you can do to improve blood flow
• Manage your diabetes and blood pressure as advised by your doctor
• Check your feet daily for any cuts, blisters, or redness
• Keep your skin clean and dry, and moisturise cracked skin

Medical treatments

Doctors may prescribe medications to improve blood flow, control infection, or manage pain. They may also recommend wound dressings, antibiotics for infections, or angioplasty (a procedure to open blocked arteries) to try to save the leg. If these do not work, amputation may be the best option to stop the problem from getting worse.

When is surgery considered?

Surgery is recommended when the leg cannot be saved because of severe lack of blood flow, extensive tissue death (gangrene), uncontrollable infection, or cancer that cannot be removed in another way. The surgery is done under general anaesthetic (you are asleep) and usually takes 1–2 hours.

Living with this condition

After healing, most people use a prosthetic leg. It takes time and practice to learn to walk again. You may need a walking aid at first. Many people return to work, drive, and enjoy hobbies. Regular check-ups with your prosthetic team are important to adjust the fit and function of your artificial limb.

Lifestyle tips

• Keep a healthy weight to make walking easier and protect your other leg
• Wear proper footwear and check your remaining foot daily for any problems
• Avoid activities that could cause injury to your stump (the part left after amputation)
• Stay active with exercises that are safe for you, like swimming or cycling

Diet and exercise

A balanced diet rich in protein, vitamins, and minerals helps wound healing and overall health. Exercise such as gentle stretching, leg lifts, and balance exercises can strengthen your muscles. Your physiotherapist will give you a tailored programme. Activities like swimming are kind to your joints and great for fitness.

Mental health and emotional wellbeing

Losing a limb can bring feelings of grief, anger, or sadness. It is normal to need time to adjust. Phantom limb pain (feeling pain in the missing limb) is common but can be managed. Talking to a counsellor or joining a support group can help you cope. If you feel very down or anxious, please tell your doctor – there is help available.

Prevention

Many below-knee amputations can be prevented by managing underlying health problems. If you have diabetes or peripheral artery disease, regular foot checks, good blood sugar control, quitting smoking, and treating infections early can greatly reduce your risk. If you have leg pain or a wound that does not heal, see a doctor right away.

Screening programmes

If you have risk factors like diabetes or a family history of artery disease, your doctor may recommend regular checks of your leg pulses and ankle-brachial index. This can detect poor blood flow early, before it causes serious damage.

Complications

If left untreated

• Infection at the amputation site that may spread to the bone
• Poor wound healing requiring more surgery
• Phantom limb pain (pain felt in the missing limb) that does not improve
• Problems with the other leg due to the same underlying disease
• Stump (residual limb) pain or skin problems from the prosthesis

Long-term outlook

Most people do very well after a below-knee amputation. With good medical care, rehabilitation, and a properly fitted prosthesis, you can walk again and return to many of the activities you enjoy. Your chances of a good recovery are highest when you follow your healthcare team's advice and stay positive. Remember, you can still live a full, active life.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.