Call us for assistance: 309.676.2276

Home » Prosthetics » Lower Extremity

According to the National Limb Loss Information Center, in the United States there are approximately 1.7 million living with limb loss. It is estimated that one out of every 200 people in the U.S. has had an amputation. The most common reason for amputation are vascular complications (mainly diabetes), cancer, and trauma. Regardless of the reason for your amputation, you are not alone. While your personal experience of limb loss is unique, many others have successfully overcome the loss or absence of a limb and regained function and a positive outlook.

There will be many questions along the way as you prepare for your life as an amputee and the best course to take is to communicate with those on your rehabilitation team. Your physician, physical therapist, occupational therapist, and prosthetist are those who are here to help you become a successful wearer of a prosthetic device, but it it ultimately up to you to take charge of your care and your life as an amputee.

leg-amputation-types

Levels of lower extremity amputations:

Post-Operative Management:

There are several methods of post-operative care your surgeon may use, depending mostly on your level of health, condition of the residual limb and potential as a prosthetic candidate. Typically, after surgery your surgeon will apply a dressing that is intended to reduce swelling and protect your limb. After the initial surgical dressing is removed, you may receive one of the following devices.

dressing-1

A rigid dressing is typically applied 2-3 days after surgery.  The purpose of this cast is to keep your leg in extension (straight), protect your residual limb from bumps or accidental falls, and to keep your limb clean and un-disturbed so that the healing process can take place.  A foot section may be applied which helps with gait training and light touch weight bearing while in the hospital.  This cast is non-removable and remains in place for 7-10 days at which time is removed and your limb is inspected by your surgeon.  There are typically 2-3 cast changes involved with this process.

dressing-2

A rigid removable dressing or protector as it is commonly called may be used initially after surgery or once the series of rigid casts have been utilized.   This is approximately 4 weeks post-operative.  The purpose of this device is to control edema, protect, and shape the limb for future prosthetic fittings.  This device is removed several times per day and the fit is modified with prosthetic socks.  This device is used until a prosthesis is being worn consistently.

Flotech is another type of protector that has similar qualities as the rigid cast and the removable dressing.  This is not a custom protector like the other styles but does offer some protection from accidental bumps.  Compression and prosthetic socks are utilized with this device as well.

dressing-prosthetics-

Compression or AK/BK Shrinkers are used to control edema and shape the limb.  Compression is used in all post-operative devices but is also used alone in some cases.  This is the minimal amount of post-operative management you may receive.   Shrinkers may be in the form of an open-ended tube which is rolled onto your limb and then reflected at the bottom of your limb for a second layer or a single layer sock that is stitched at the bottom.  Either way it is important that you pull the sock snug to the bottom of your limb to reduce the chance of swelling.

dressing-3

Immediate Post-Operative Dressing – is placed on your limb in the operating room immediately after surgery. The purpose of this dressing is for mild protection of the limb; keep any post-operative swelling under control and to allow for inspection of the incision. The surgeon’s initial dressing may vary and could be either a sterile post operative sock or an ace wrap bandage, both of which are wrapped over sterile dressing.

Compression Socks or AK Shrinker – are used to control edema and shape the limb. Compression is used in all post-operative devices but is also used along in some cases. This is the minimal amount of post-operative management you may receive. Shrinkers may be in the form of an open-ended tube which is rolled onto the limb and then reflected at the bottom for a second layer and held in place with a hip belt; or a single layer sock that is stitched at the bottom. Either way, it is important that you pull the sock sung to the bottom of you limb to reduce the chance of swelling.

Transfemoral Preparatory Prosthesis – is a rigid co-poly plastic socket that is made from a model of the limb. This is usually done 3-5 days after the surgery. This is a device that is worn with compression and prosthetic socks which will allow a patient to begin gait training soon after surgery. This device has a waist belt for suspension, a manual-locking knee, a pylon and a single-axis foot. This device is usually prescribed for those patients who are more mobile and able to utilize the prosthesis soon after surgery.

Post-Op Preparatory Prosthesis:

Transfemoral Preparatory Prosthesis (AKA) is a rigid co-poly plastic socket that is made from a model of your limb.  This is usually done 3-5 days after your surgery.  This is a device that is worn with compression and prosthetic socks which will allow a patient to begin gait training soon after surgery.  This device has a waist belt for suspension, a manual-locking knee, a pylon and a single-axis foot.  This device is usually prescribed for those patients who are more mobile and able to utilize the prosthesis soon after surgery.

This type of device can also be made for a Transtibial or Below Knee amputee (BKA) after surgery as well, usually 1-3 weeks after surgery.  Typically, the prosthesis is made out of a co-poly plastic socket, used with prosthetic socks, a suspension sleeve and a SACH prosthetic foot.

The Rehabilitation Process:

Rehabilitation begins soon after surgery. The amputee will work with physical therapy in the hospital and will most likely continue after being discharged. Typically, most people are fit with a prosthesis 6-8 weeks after surgery but it may take longer depending on personal circumstances. Once you have been fit with your first prosthesis your physician will order out-patient therapy (at a rehab facility) or therapy can be provided in the home if need be.

The Fitting Process – When your physician has given clearance to begin the prosthetic fitting, your prosthetist will take a cast or a scan of the limb; this will provide him/her with a model to make the prosthesis. Prior to this appointment he/she will have assessed your individual needs and goals for life as an amputee. This includes  but is not limited to determining how active you are or would like to be, your current weight, occupation or leisure activities, current health status (if there are other health factors that may need to be accommodated), and the condition of the residual limb. This information is extremely important when determining the components and which type of prosthetic device is most suitable for the individual amputee.

Check Socket and Component Selection – A clear plastic check socket (diagnostic socket) is made from the model; this is what the prosthetist will use for the initial fitting. The check socket allows the prosthetist to make changes to the fit of the socket or to change the alignment as you begin to walk. The check socket is typically utilized for one or two weeks while beginning therapy. Your prosthetist will follow-up with you as well as your therapist to ensure the fit and the function of you prosthesis is optimal and to address any issues immediately. As you become stronger, more flexible and confident on the prosthesis, your gait (the way you walk) will change and therefore your prosthetist will need to make changes to your alignment. Your check socket will consist of a clear socket, means of suspension, knee (for above knee amputees), pylon and a foot. The components that are used in your prosthesis are determined by your prosthetist.

Definitive Prosthesis – Once the fit of the prothesis has been determined and no immediate changes are needed, the definitive (permanent) prosthesis will be made; typically this is after you have completed physical therapy. Normally it takes about four days to finish a prosthesis, but maybe longer if there is a protective cover applied. A definitive prosthesis is a much stronger and more durable version of the check socket used in the fitting process. This socket is constructed of carbon fiber, nylon, resin, and other materials that give it its strength.

Typically, the limb will continue to change as you begin to wear the prosthesis more consistently. You will need to follow-up with your prosthetist regularly so that he/she can accommodate those changes. To become a successful wearer of a prosthesis it is best to follow the recommendations of your physician, prosthetist and physical therapist and it is imperative to follow through with all appointments and call when you are having issues. If you are having pain or discomfort call immediately so that your prosthetist may remedy any problems before they worsen.

Components of lower extremity prosthetics:

Socket Design: Depending on your level of amputation, there are several types of socket designs that one could be fit with. Your prosthetist will determine which socket design is best suited for you based on the shape and the condition of the residual limb. Other factors include length, circumference and skin integrity. The most common socket designs for below-knee-amputees (BKA) are Patellar Tendon Bearing (PTB) which means the pressures inside the socket are placed on pressure tolerable areas (muscle and tendon) and relieved in pressure sensitive areas (boney area). A Total Surface Bearing socket (TSB) means that the pressures are spread more evenly over the entire limb. The use of a silicone or urethane interface flows over the limb, thinning out over pressure tolerant areas and remaining thick over areas that are pressure sensitive.

For above-knee amputees (AKA) the most common socket design is the Ischial Containment design. The prosthetic socket for a transfemoral amputee needs to support your weight, contain your tissue and your limb comfortably, and provide stability so that you can walk as efficiently as possible.  Achieving a good fit is imperative to becoming a successful user of a prosthesis.  The main pressures inside the prosthetic socket are absorbed by the bony anatomy of your pelvis (ischial tuberosity), which are the bones you sit on and can feel when sitting on a hard surface.

Suspension Techniques: There are many ways to suspend a prosthesis. Some of the more common techniques are as follows: Supracondylar suspension which is suspension above the bony anatomy of the knee. Silicone suspension uses a liner that is rolled onto the limb which has a pin attached into a lock into a mechanism inside the prosthesis. Seal-in suction is also a liner that is rolled onto the limb but this design has a sealing ring, or rings, that seal against the walls of the prosthesis. Vacuum suspension is another technique that uses the TSB socket design ( for below knee-amputees ) and vacuum pump to mechanically hold the prosthesis on the limb with suction. This design provides excellent adhesion and improved wearer comfort.

dressing-4

Prosthetic Knees: Prosthetic knees today offer many different options for amputees of all levels.  Depending on your level of activity and specific circumstances, your prosthetist will choose a knee that will provide you with what is most appropriate.  A Manual Locking Knee is the most stable type of knee available.  A Single-Axis, Constant Friction Knee is simple, inexpensive and lightweight.  A Single-Axis, Constant Friction Knee with Stance Control has a breaking feature that prevents the knee from buckling when weight is put on the leg.  A Single-Axis, Fluid Friction Knee varies its resistance as walking speed varies or when running.  A Polycentric Knee is a very stable knee that allows for very fluid walking.  A Microprocessor Knee is a computerized knee that responds automatically to the walking patterns of the patient and has added stability.

prosthetics-with-vaccum

Prosthetic Feet: Prosthetic feet are categorized by levels of activity; this means how well you ambulate (walk). Examples are: if you walk with an assistive device (walker or cane), if you walk in varying speeds, or if you lead an active lifestyle and participate in sports or other recreational activities. The type of foot that is prescribed will vary. Other factors that determine the type of foot that is chosen are your body weight, if you walk on uneven surfaces, the type of job you have and the length of your residual limb.

foot-prosthetics

Prosthetic feet are categorized as: SACH (solid ankle cushioned heel), single-axis (one plane of movement), multi-axial (more then one plane of movement), and dynamic response (materials used in the foot return energy to the patient when walking). Speaking with your physician and prosthetist regarding your goals will help determine which prosthetic foot will be the most appropriate and which foot will help return you to a more active and independent lifestyle, much like you had prior to limb loss.

ankle-prosthetics
 

Ask The Expert

If you have any queries regarding our practice or how we can help you, fill out our Patient form or Physician form or call Comprehensive Prosthetics and Orthotics and speak with a Certified and Licensed Prosthetist. We would appreciate the opportunity to provide the most up to date and effective prosthetic care that can only be given by those who truly care about your health and well-being.