Lower Limb Prosthetics
The design of a prosthesis is based on considerations like your overall health, activity level, strength and flexibility, employment requirements, hobbies and interests. The prosthesis consists of a custom socket to fit your residual limb and component parts like knees and feet, which are selected to fit your specific needs. All parts of the prosthesis require regular maintenance and occasional replacement to ensure optimal function.
Partial Foot Amputation
Partial foot amputation is a common secondary to advanced vascular disease secondary to diabetes and its complications but may also occur due to injury, infection, or birth defect. This is associated with a significant failure rate and numerous complications including skin breakdown, ulceration and equines contracture which can lead to subsequent and more proximal amputation. PFA can include; toe amputations, trans-metatarsal (TMA) amputations and Chopart amputations.
Symes Amputation
A Syme’s amputation is an ankle disarticulation (the removal of the foot through the joint) while the malleoli stays intact (the two rounded protrusions on either side of the ankle) then forward rotation of the heel pad over the end of the residual tibia for weight bearing.
This is the term used to describe an amputation that is through the ankle joint. For a person with this type of amputation, they have a full-length tibia and fibula, but no ankle joint and foot. For most of these patients, the shape of the limb itself can be used to suspend the device with the use of either a foam or gel liner.
Trans-tibial /
Below the Knee
Amputation
A trans-tibial (TT) is an amputation often performed for foot and ankle problems. The TT often leads to the use of an artificial leg that can allow a patient to walk and is performed roughly in the area between the ankle and knee. This provides good results for a wide range of patients with many different diseases and injuries. The variety of prosthetic options for TT amputees has exploded in recent history. With motor powered foot prosthetics, shock absorbing feet, and auto-adjusting feet all now available, a skilled prosthetist is more important than ever to determine the best prosthetic foot for your needs. Socket designs, foot designs, and gel and silicone skin interfaces have all advanced dramatically.
These individuals still have control of their knee joint but do not have an ankle or a foot. For these clients, we sometimes incorporate the shape of their knee anatomy into the design of the socket for suspending the prosthesis. Other suspension techniques may include suction or mechanical locking devices used in conjunction with a roll-on gel liner. The gel liners provide a two-fold job. First, as a skin-socket interface to protect the limb from excessive irritation and second, to provide suspension. The liners can come with pin attachments that slide into a locking mechanism in the bottom of the prosthetic socket.
Trans-femoral /
Above the Knee Amputation
A trans-femoral (TF) amputation describes individuals that no longer have a foot, ankle and knee. This amputation can be a result of vascular complications, trauma , osteosarcoma, or a previous below knee amputation.
These patients may also take advantage of the same gel liner technology that incorporates a pin for suspension or traditional suction to suspend their prosthesis. With this type of amputation special care is taken in designing the socket, suspension and choosing the appropriate knee and foot that will best fit the activity level and needs of the patient. The most important portion of a prosthesis is the socket, which is the component that comes into direct contact with the residual limb.
The knee disarticulation prosthesis would have similar component make-up to that of an above knee amputation. This type of amputation is in which the person has lost their limb or had an amputation through the knee joint. This means they have a full-length femur, “thigh bone” but no functional use of an anatomical knee joint so a mechanical knee is used in its place.
Hip Disarticulation
Hip disarticulation is the surgical removal of the entire lower limb at the hip level. A traditional hip disarticulation is done by separating the ball from the socket of the hip joint, while a modified version retains a small portion of the proximal (upper) femur to improve the contours of the hip disarticulation for sitting. A hip disarticulation results most often from trauma, tumors and severe infections, such as necrotizing fasciitis. Less often, it results from vascular disease and complications of diabetes. A hip disarticulation prosthesis consists of three artificial joints, the hip, knee and ankle.
Amputee Care
Facing amputation through elective surgery or a traumatic event can feel overwhelming. Knowing what to expect during each step of the process can ease some concerns and being prepared has been proven to speed recovery and expedite the rehabilitation process.
Even though you won’t be cast for your prosthetic for a few weeks, you will start the process of rehabilitation and preparing your residual limb for your prosthetic immediately after your surgery. In these early weeks, your limb will be very bulbous and swollen and may have small “dog ears” where the skin comes together at the incision. The incision will be closed with stitches and staples, which will gradually be removed as you heal. You will likely wear a protective covering for your limb to protect it if you fall, prevent infection and keep your leg fully extended to prevent muscle contractures.
The early weeks of recovery are a crucial phase with three main goals:
Caring for your residual limb
Reducing your swelling
Keeping your residual limb clean.