Amputation is not a failure of treatment. For a limb that is beyond salvage, or salvaged but useless and painful, a well made below knee stump with a good prosthesis restores more walking than years of failed reconstruction.
A below knee amputation removes the leg below the knee joint while preserving the knee itself. Keeping the knee roughly halves the energy needed to walk compared with an above knee amputation, so it is preserved wherever the blood supply and tissue allow. The stump is shaped deliberately for a prosthesis, and most patients walk again with rehabilitation.
The knee does most of the work of walking. Someone with a below knee amputation and a well fitting prosthesis uses roughly a quarter more energy than normal walking. An above knee amputee uses closer to double. That difference decides whether an older or frailer person walks again at all, which is why the knee is preserved whenever the tissue and blood supply permit.
This is also why amputation is sometimes the right recommendation rather than further reconstruction. A foot that has been operated on repeatedly, is insensate, painful and will never bear weight, keeps a patient in hospital and out of life. A below knee amputation with a prosthesis frequently gives more function and more independence than continuing to salvage it.
The operation itself is reconstructive. The aim is a stump of the right length, usually a hand's breadth below the knee, with the calf muscle brought round and secured over the bone end to provide padding, the bone edges bevelled so nothing presses through the skin, and nerves cut cleanly and allowed to retract so they do not form painful nodules in a pressure area.
Where the patient's circulation is marginal, getting that healing is the whole challenge, and the level is chosen on blood supply rather than on how much can be preserved.
The level is chosen by blood supply and tissue quality, not by preference. Healing at the chosen level matters more than the level itself.
Blood supply, tissue quality and the extent of infection determine the level. Healing at a slightly higher level beats a failed longer stump.
A long posterior flap of calf muscle and skin is marked, because that tissue has the best blood supply and provides the padding.
Tibia and fibula are divided, the tibia bevelled at the front so no sharp edge presses into the skin, and the fibula cut slightly shorter.
Nerves are drawn down, divided cleanly and allowed to retract into muscle, away from the weight bearing surface, to reduce painful neuroma formation.
The calf muscle is brought over the bone end and secured, giving a padded, stable stump rather than skin directly over bone.
Skin is closed without tension and a rigid or soft dressing applied to control swelling and protect the stump.
Pain control, including for phantom sensation. The knee is kept straight with a board or splint to prevent contracture. Sitting out of bed early.
Wound heals. Stump shrinker or compression begins to shape the limb. Physiotherapy for strength, balance and transfers. Early walking aid training.
First prosthesis fitted once the wound is sound and the stump shape is settling. Gait training begins.
The stump continues to shrink and the socket is refitted, often more than once. Walking distance and confidence build.
Most patients who were walking before surgery walk again with a prosthesis, and many describe being more mobile than in the months of failed salvage beforehand. It takes time: around six to twelve weeks before a definitive prosthesis is fitted, and several months of rehabilitation after that. Phantom sensation is normal and usually settles; phantom pain affects a minority and is treated. The stump changes shape over the first year and the socket needs refitting more than once, which is expected rather than a problem.
These patients often have significant vascular disease, diabetes and infection, and the risks reflect that.
Stump shaping and preventing knee contracture are the two jobs of the first weeks.
Often it is the option that restores the most function. A painful, insensate, unusable foot after years of surgery leaves people less mobile than a good below knee stump with a prosthesis.
Most patients who were walking before surgery walk again with a prosthesis, particularly when the knee has been preserved and rehabilitation is followed.
Not if it will not heal. A stump at a level with good blood supply that heals first time is far better than a longer one that breaks down and needs revising.
Feeling the missing limb is normal and experienced by most amputees. Painful phantom sensation affects a minority and there are effective treatments for it.
A below knee stump is a reconstruction, and it is built for the prosthesis that will be fitted to it. Muscle padding, bone contour and nerve handling all decide whether the socket is comfortable a year later.
Amputation and the rehabilitation that follows are commonly covered by health insurance and by government schemes including PM JAY. Prosthetic costs vary widely by type and are planned separately. A written estimate covers the surgery and admission.
Almost always asked with fear, and usually about walking.
Ask your question →Most patients who were walking beforehand do, with a prosthesis and rehabilitation. Keeping the knee is the single biggest factor, which is why it is preserved wherever the blood supply allows.
The level is chosen where there is enough blood supply to heal and enough tissue to pad the bone. A foot level amputation that will not heal leads to repeated surgery, which is worse than a below knee stump that heals first time.
Usually six to twelve weeks, once the wound is sound and the stump shape has begun to settle. An early training prosthesis is sometimes used sooner. The socket will need refitting as the stump shrinks over the first year.
Feeling the missing limb is normal and most amputees experience it. Painful phantom sensation affects a minority, usually improves with time, and there are medications and techniques that help.
Because a knee that sits bent for a few weeks can become fixed in that position, and a prosthesis cannot be fitted to a permanently bent knee. It is the most important thing you can do in the first fortnight.
Seeing patients from across the city and beyond: read about the practice on the plastic surgeon in Surat page, or check what a written estimate covers on the costs and insurance page.
