FAQ

 

1. What is a trans-femoral amputation?

The trans-femoral amputation (above-knee) is a surgical procedure in which a portion of the femur (thigh bone) is cut and removed from the body along with the lower leg and foot. Amputation of the lower extremity is often the treatment of choice for an unreconstructable or a functionally unsatisfactory limb. Amputations are either caused by accidents, disease, and congenital disorders. Approximately 74% are due to peripheral vascular disease (poor circulation of the blood) and cancer; 23% are due to accidents, and 3% are due to a problem found at birth (Muilenburg & Bennett, 1996).

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2. Why does the residual volume change and how significant is it?

The problem with changing limb volume is both long term and short term. Firstly, there is the natural shrinkage of the limb that occurs over a long period; this change is permanent. This can be up to 5% in the first 200 days and is reported to be as large as 15% over two years. This volume change is not evenly distributed over the limb and is generally the result of postoperative muscle atrophy, discrete postoperative fluid collections, generalized potoperative edema, injuries to the limb, and muscle atrophy from inactiviy. Secondly, volume changes can happen on a daily basis and this presents a more consistent problem for liftime of all sockets. The amount of daily volume fluctuation is likely to vary greatly among individuals with amputation as a function of comorbidities, prosthesis fit, activity level, ambient conditions, body composition, dietary habits, and sex.

 

3. What are the major problems caused by an ill-fitting socket?

Three major problems caused by an ill fitting:

• the limb cannot fit into the socket or remain attached

• ill fitting prevents the support of transverse moments

• irregular contact leads to harmful pressure disparities