TYPES OF AMPUTATIONS
Partial foot and Symes Amputation:
A partial foot amputation is the removal of one or more toes, or the removal of part of the foot, while still leaving the ankle joint intact and functioning. The amputations a commonly seen in older patients and would most often be done because of a non-healing, often infected neuropathic plantar ulcer. These ulcers are usually accompanied by sensory impairment, weakness of the intrinsic muscles of the foot and impaired circulation.
Partial foot amputations can be divides into subsections including:
- Toe amputations: Just the removal of one or more toes.
- Ray resections: The removal of one or more toes as well as sections of or the entire metatarsal bone.
- Transmetatarsal amputations: This is basically ray resections of all 5 toes and would sometimes be referred to as a forefoot amputation.
A Symes amputation involves removing the entire foot but keeping the fat pad and soft tissue from the heel so that the patient will be able to stand on the residual limb. Al though this type of amputation allows the patient to stand on it, it is not recommended that the patient does a lot of walking on the residual limb. This because the amputated leg is shorter than the sound leg and prolonged walking on the residual limb could result in secondary postural; conditions due to the leg length discrepancy.
Transtibial amputation:These amputations are also referred to as below knee amputations and involves the removal of the lower leg while keeping the knee joint intact and functioning. Transtibial amputations come in many shapes and sizes, with certain characteristics being more favourable than others. Short transtibial residual limbs tend to be a challenge because of the small surface area available to carry weight when walking. An ideal below knee residual limb usually has 15cm length below the knee (tibial length).
The shape of the residual limb is not the only factor to consider when designing a prosthesis. Most patients need to do a lot of rehabilitation after the amputation to ensure that their muscles are strong enough to walk with a prosthesis and to avoid contracture of the residual limb. With this type of amputation the patient is not able to carry any weight on the bottom of the residual limb, this is because there is no fat pat or wide bony distal end to transfer the weight over a larger area.
With a transtibial amputation the patient carries the bulk of their weight on the patella tendon which is just below the kneecap, but it is not always the case and it depends mainly on the type of suspension and socket.
Knee Disarticulation:This type of amputation is done right though the knee joint and is in some cases consider more favourable in comparison to a very short transtibial amputation. A knee disarticulation has many benefits in comparison to an above knee amputation. The patient can easily carry weight on the distal end and all the upper leg muscle are still intact, so most knee disarticulation patient have a very functional residual limb. One of the only disadvantages of this type of amputation is that it has a negative effect on the knee placement and this result in the prosthetic knee not bending at the same point as the sound leg’s knee. Few patients notice the effect of it initially, but it can affect the hip and lower back later in life.
Transfemoral:A transfemoral amputation is a lower extremity amputation done by cutting through the femur, the large bone in the upper leg. It is also known as an above-the-knee amputation, and the precise height of the amputation varies, depending on the case. When preparing for a transfemoral amputation, the doctor takes some time to plan ahead, selecting the optimal position for the patient's future ability to balance and use a prosthesis without compromising the quality of medical care. This amputation is challenging to adapt to, as the loss of the knee joint makes it harder to learn to walk again, and the experience can be emotionally traumatic.
Studies on people with transfemoral amputations have shown that they invest more energy in walking than people with below-the-knee amputations and individuals with both legs intact. During recovery, this can lead to rapid onset of fatigue as the patient learns to walk and adjusts habits to adapt to the limb loss. In the case of double amputees, the recovery period can be long as the patient develops adaptations and new life skills.
Hip disarticulation:This amputation involves removing the entire leg at the level of the hip. This isn’t a very common type of amputations and surgeons try and avoid it as much as possible, because patients who have undergone this type of amputation usually struggle to adapt to prosthetic use. Some studies have shown that hip disarticulation patients are the most likely to not use their prosthesis in comparison to lower levels of amputation. A proper rehabilitation plan is of utmost importance for these patients, because that we determine how likely they are to keep using a prosthesis.
A hemipelvectomy is an amputation similar to a hip disarticulation but involves the removal of a part of the pelvis as well. The prosthetic design of the prosthesis would be very similar to that of a hip disarticulation with a few minor changes depending on how much of the pelvis has been removed.