PROSTHESIS MUHAMMAD FARRUKH BASHIR FCPS(ORTHO) MUHAMMAD FARRUKH BASHIR FCPS(ORTHO)

Definition A prosthesis is an artificial replacement for any or all parts of the lower or upper extremities, it is a device that is designed to replace, as much as possible, the function or appearance of a missing limb or body part.

Purpose  A prosthesis is used to provide an individual who has an amputated limb with the opportunity to perform functional tasks, particularly ambulation (walking), which may not be possible without the limb.  The prosthesis may also be made for use during activities or sports, such as dancing, swimming, cycling, golfing, and climbing.  The type of prosthesis (artificial limb) used is determined largely by the extent of an amputation or loss and location of the missing extremity.amputation

Characteristics of a successful prosthesis:  Be comfortable to wear,  Easy to put on and remove,  Lightweight  Durable, and cosmetically pleasing.  Function well mechanically and require only reasonable maintenance.  Depends on the motivation of the individual, as none of the above characteristics matter if the patient will not wear the prosthesis

Considerations when choosing a prosthesis :  Amputation level.  Contour of the residual limb.  Expected function of the prosthesis.  Cognitive function of the patient.  Vocation of the patient (eg, desk job vs manual labor).  A vocational interests of the patient (ie, hobbies).  Cosmetic importance of the prosthesis.  Financial resources of the patient.

Problems may occur when using prosthesis are:  The poor fitting of the prostheses, causes unequal weight load to lower limbs. This may cause extra stress or pressure on the other (unaffected) leg, or on the stump. The increased pressure may lead to pain and skin problems. Skin breaks that are not treated can become infected. Over time, this may also make another amputation necessary.  Walking with prosthesis on takes extra energy.  The stump should be checked every day for redness, blisters, soreness, or swelling.  Prosthesis need to be adjusted several times before it fits well.

Steps in manufacturing  Measurement of the stump.  Measurement of the body to determine the size required for the artificial limb.  Creation of a model of the stump.  Formation of thermo-plastic sheet around the model of the stump – This is then used to test the fit of the prosthetic.thermo-plastic  Formation of permanent socket.  Formation of plastic parts of the artificial limb –  Different methods are used, including vacuum forming and injection molding.vacuum forminginjection molding  Creation of metal parts of the artificial limb using die casting.die casting  Assembly of entire limb.

Prostheses are either preparatory (temporary) or definitive (permanent).  temporary prosthesis is fitted while the residual limb is still maturing. A preparatory prosthesis allows the patient to train with the prosthesis several months earlier in the process. Use of a preparatory prosthesis often results in a better fit for the final prosthesis, since the preparatory socket can be used to mold the residual limb into the desired shape. During this period, the patient “test drives” the prosthesis and learns what it can and cannot do.

The advantage to using a temporary prosthesis :  It shrinks the residual limb more effectively than the elastic wrap.  It allows early bipedal ambulation.  Certain individuals can return to work.  It is a positively motivating.  It reduces the need for complex exercise program.  It can be used by individuals who may have difficulty obtaining payment for permanent prostheses.

Lower Limb Prostheses  There are several levels of lower limb amputation, including:  1) Partial foot,  2)Ankle disarticulation,  3) Transtibial (below the knee),  4) Knee disarticulation,  5) Transfemoral (above the knee),  6) Hip disarticulation.  The most common are transtibial (mid-calf) and transfemoral (mid-thigh).

Lower Limb Prostheses

Upper Limb Prostheses