The term amputation describes an operative or in rare cases also traumatic separation of a body part, a limb or other appendages of the body. Such interventions are performed only if the preservation of the corresponding body part is no longer possible or if the life and health of the patient is irreversibly endangered.
If after a failed attempt of replantation the non-perfused limb must be removed again, one speaks of a reamputation.
Occurrence/Frequency
The absence of an amputation register in Germany makes stating the exact number of amputations impossible.
The German Society for Angiology estimates about 60,000 amputations performed every year in Germany, a relatively high number compared to other European countries.
According to the medical newspaper Ärzte-Zeitung, approximately 70-80% of the amputations in Germany are caused by the peripheral artery occlusive disease (PAOD) in diabetics. Usually it means lower leg amputation. (Leg amputation) Therefore diabetics have a 10-15 times higher amputation risk than non-diabetics. Men are more likely to be affected.
How can you be sure you really need an amputation?
There are many causes for an amputation, therefore different types of diagnosis should also be utilized.
At first there is of course a comprehensible patient interview (anamnesis), a survey of typical risk factors such as smoking or diabetes mellitus and physical examination.
If a circulatory disorder is present, it must be determined to what extent the blood flow in the affected vessels is restricted. Firstly, a physician tries to feel pulse in the affected extremity and measure the blood pressure. As the legs are usually affected, some functional test can also be performed. For example, a treadmill is used to test how far the patient can go.
Doctors can see the reduced blood flow using an X-ray with a contrast agent (angiography) or ultrasound (duplex sonography) vascular imaging. Based on these tests physicians decide whether the limb can be preserved.
Imaging techniques are also used for diagnostic tumors or traumatic injuries. These include:
- X-rays, e.g. for fractures
- Computed Tomography (CT)
- A radioactive imaging procedure (scintigraphy).
In addition, blood tests are often carried out.
Based on these examinations, the doctor can determine whether and where the limb must be removed.
Surgical complications
Following complications can be caused by the operation:
- Damage to surrounding tissues
- Bleeding
- Infections
- Wound healing disorders
- Scar formation
- Pressure damage from by the prosthesis
- Neuralgia
- Unnatural connections between veins and arteries (shunts) as well as
- Paralysis
A major problem for an amputee is the phantom pain. Despite the absence of a body part, patients still feel pain and discomfort in the no longer existing arm or leg.
The changed posture can also cause damage to the spine and joints.
Prognosis
The following indicates a successful healing of the operated body part:
- Good lymphotrophy of the local tissues
- Presence of arterial pulse above the amputated part
- A satisfactory blood circulation with healthy color and temperature of the skin
- Subsiding of local infection and swelling (edema)
- No redness in the amputation area in case of a hanging limb and a rapid filling of venous vessels
- No pain in the low perfused tissue (ischemia) when at rest
- Painless scars.
Since all damaged tissues were removed by the amputation, consequential damages are rather rare.
However, if the inflammation has already spread thought the body or if the tumor cells were scattered before the amputation was performed, the life of the patient can often not be saved despite the surgery.
Of course, the patient's state before the removal of a limb cannot be fully restored, but prosthetics can take over most of the limb functions.
In addition, a pain sensation can develop in the amputated body part, it is a type of neuralgia known as phantom pain.
Amputation causes
There can be as many causes for an amputation, as there are amputation points. If the lower leg needs to be surgically removed, the reason is usually diabetes mellitus, if the upper extremity is concerned, the most frequent cause for an amputation is an accident.
Firstly, there can be traumatological reasons for an amputation, if an accident is the cause.
After injuries, e.g. after a car accident, that are accompanied by a severe damage of:
- the skin and soft tissue mantle
- the blood perfusion
- the bone structure
it is often no longer possible to save the affected body part.
A septic cause can be an uncontrollable infection, e.g. after an accident (trauma) or a pathological tissue destruction (wet gangrene).
But amputation can also be necessary in case of tumor diseases. In the case of uncontrollable, malignant soft or bone tumors in the area of the arms or legs (extremities), surgical removal of the extremity can sometimes be inevitable in order to avoid progression or even spreading of the tumor.
In case of strong functional limitations, for example a rigid and curved finger, which impairs the movability of the hand and the other fingers, an amputation can be helpful, although at first it may not sound rational. The functional restriction can be so strong that an amputation of a finger becomes meaningful.
Another common reason for an amputation are angiological causes, hence vessel diseases. Incurable circulatory disorders with skin and soft tissues destruction (necrosis) near larger vessels plaqued by calcification and narrowing (arteriosclerosis) or by constipation by a blood clot (embolism) are also often a reason for an amputation.
Diabetic foot syndrome often leads to an amputation. The peripheral neuropathy associated with the disease leads to nerve damage which is accompanied by dysesthesia or even discomfort in the legs. The damage slowly progresses from the foot to the thigh. Together with the dysesthesia the patients also experience a reduced sensation of pain, so that the affected persons do not feel pain even under extreme pressure, which normally should serve as a warning symptom from the body about tissue destruction.
The paresthesia results in an incorrect distribution of compression load or wrong footwear which in turn can lead to skin defects (ulcers) that are detected too late.
The case is the same with burns. The untreated skin lesions become infected, bacteria can grow and cause massive changes leading to the destruction of the soft and bone tissue.
In addition to peripheral neuropathy, diabetics often suffer from peripheral arterial occlusive disease or a diabetic microangiopathy, i.e. calcification of small vessels.
Because of the vessel calcification, which leads to a limited oxygen and nutrients supply of the legs, there is no guaranteed sufficient supply of the tissues in critical conditions such as pressure loads or injuries. Thus, wound healing disorders with tissue destruction (wet gangrene) occur, which can lead to a complete natural separation of the toes and later of the tissue above.
Accompanying symptoms
Accompanying symptoms that can precede an amputation are badly healing or even not healing wounds on the arms or legs, as well as persistent pain. If these symptoms occur not only under load, but even at rest, an imminent amputation can no longer to be avoided.
A severe infection, which ultimately leads to an amputation, is often accompanied by symptoms such as fever, chills and fatigue.
After an amputation, if the wound heals well there should be no accompanying symptoms except for the functional loss caused by the amputated body part. However, since mostly patients with a weak immune system (for example diabetics) and insufficient circulation require an amputation, wound healing disorders are not uncommon especially in the case of larger amputations. In particular, pain in the area of the stump can occur. In some cases, patients also complain about the so called phantom pain. This means that the patient experiences pain or other unpleasant sensations (for example itching) in the amputated part of the body.
Amputation level
The fixed determination of the amputation level using the so-called amputation schemes with classification into valuable, expendable and obstructive parts of the extremity that was made in the past is today obsolete and being rejected.
When determining the amputation levels and forms it is important to take into consideration the load capacity and suitability of the stump for the attachment of a prosthesis.
Hand, elbow and shoulder amputation
The highest amputation of the upper extremity is through the shoulder belt, i.e. between shovel (scapula) and thorax.
Such amputation is usually caused by malignant tumors and induces considerable cosmetic and functional impairment. Similar are the consequences of a shoulder disarticulation, i.e. an upper arm amputation in the area of the shoulder joint.
In case of an amputation at the upper arm bone level, physicians must ensure that there is enough space for an artificial elbow joint at the height of the amputation.
Disarticulation (amputation) at the elbow joint level is difficult by itself, since the protruding bone parts produce painful pressure points in the area of the prosthetic socket.
In the hand area, in addition to the load capacity also the stump length, the sensitivity, the joint mobility and the possible grip forms have to be considered.
Leg, foot and lower leg amputation
In the area of the lower extremity, the type of load form differs from the one of the upper extremities.
In the case of a midfoot and tarsal amputation, the physicians need to ensure that enough stable foot sole skin and the underlying fat layer as well as the short foot flexor muscles is left to cover the stump and the scars on the extensor side, hence on the back of the foot, are out of the stress zone, otherwise they can create painful pressure points.
In case of a diabetic foot syndrome with necrosis (gangrene) or diabetic microangiopathy (smaller vessel disease), border zone amputations are performed at anatomically defined lines on the midfoot.
In the case of a lower leg amputation, the entire tibia and fibula can usually be retained and a separation is made just above the ankle joint (syme amputation), but this stump can only be equipped with a heavy prosthetic and often has some restrictions for weight carrying.
More often, however, an amputation is performed in the area between the upper and the middle thirds of the lower leg. The stump can be treated using myoplastic, which means that the antagonist muscles are connected around the end of the bone.
The muscle and skin flaps from the back (dorsal) are clapped to the front (ventral) to cover the stump.
The disarticulation of the knee joint, which was previously rejected due to the poor cover of the stump without musculature, is now more frequently performed in PAOD (peripheral arterial occlusive disease) patients. The advantages lie precisely in the stump length (lever arm) and the preserved muscles strength (retained thigh muscles).
In patients with vascular diseases, the amputation level is determined by the height of muscles perfusion. It may also be necessary to perform an amputation at the thigh level. The optimal height in this case is the middle of the thigh bone. The bone stump must be significantly shortened compared to the skin and soft tissue flap, so that the opposing (antagonistic) muscles can be sewn together over the thigh bone (femur).
In this type of the so-called myoplastic, the muscles are firstly fixed to the bone (myodesis), then sewn together. This helps to maintains good muscle tension and activity and ensures good cushioning.
Above all, the danger of neuroma formation is possible in the nerves supplying the thighs (sciatic nerves), so they must be suppressed (ligated) far above the amputation point.
A hip joint disarticulation is a much more difficult procedure involving a large soft tissue wound and high lethality. It should only be carried out in the case of severe infections or tumors.
Amputation of thigh
Amputations from the thigh downwards are necessary either after serious accidents or with a pronounced circulatory disorder. In the latter case, a thigh amputation is performed only if there is no longer sufficient perfusion of the lower parts of the leg and it cannot be recovered by medical means. In this case, amputations of parts of the foot or the leg have also been previously performed.
Rare diseases that may require amputation of the thigh are severe bone inflammation and some cases of bone cancer. During the thigh amputation, the bone and the surrounding soft tissues are cut close to the knee as possible to enable the maximum possible mobility of the thigh stump. However, if the thigh is poorly perfused, a higher amputation may also be necessary.
In many cases, a prosthesis can be individually adapted. However, this is significantly more difficult in case of a femur amputation compared, for example, to an amputation in the lower leg area. In particularly severe cases, the removal of the entire leg from the hip joint is required, leaving no movable stump. In addition, after this procedure phantom pain may occur.
Amputation of a toe
The amputation of a toe is usually required in case of circulatory disorder in patients with intermittent claudication or diabetes. If the toe is no longer adequately supplied with the blood filled with oxygen and nutrients, it must be amputated to avoid its necrosis that can cause inflammation.
In the case of an amputation in the foot area, doctors try to remove as little bone as possible so that the patient can still stand and walk freely. If one or more toes have to be amputated, the stability of the stand generally remains the same. However, the wound must first heal before the foot can be fully loaded again.
The amputation of a toe is a rather small procedure, which often lasts only 20 minutes. The operation can be performed either under general anesthesia or under local anesthesia of the affected leg.
The separated tissue is usually microscopically examined by a pathologist. Usually a short hospital stay after the procedure is sufficient. If necessary, the operation may even be performed on an outpatient basis.