I have a question: Is a lower or upper limb prosthesis (prosthetic device) complicated to make properly? If your answer is “yes”, you are very correct. Artificial limbs involve quite a few steps that are directly related to the final intended design. What does this mean? Depending on several factors, the prosthesis is developed, and some of these factors are: intended activity level, patient weight, length of the residual limb (remaining limb) relating to overall body height , overall body condition (weak, heart or lung issues, diabetic), patient requests relating to specific functional intended use, allergies, limb joint contractures, swelling issues relating directly to the residual limb. All the above must be taken into consideration because this will then allow the prosthetist to provide a properly considered device.
What else needs to be considered to enable the providing of a complex limb prosthesis besides all of the above? Well now were talking about the fun part, fabrication!!! Yes, for me it’s the absolute fun part. For the first step, (no pun intended) a copy of the residual limb needs to be created with great accuracy. The prosthesis suspends from the remaining limb and also, especially for the lower extremity, weight is put directly around and on it. When the person missing a limb stands on the prosthesis and walks, total body weight is loaded on the remaining limb.
The socket fit, shape and design, must be very accurate to control the great pressures per square inch that develop quickly as one stands and walks. We take our weight normally through our skeleton all the way down to our feet. When the limb is cut and we no longer have a foot or possibly a knee, we can no longer take the weight directly through the skeleton any more. The weight bearing pressure in the prosthesis must now be spread all around the residual limb in a very precise way. We must properly balance the pressure. When done correctly, there is no discomfort because the skin adjusts over a short time to the new environment it is placed in. If the prosthesis is initially used in a controlled manner, wearing the prosthesis for short periods of time and then standing and walking for short periods of time as well, the adjustment is smooth and the joy of walking develops quickly!
Second, we need to put it all together, simple, correct? No, not simple at all. Where is the best place to put the foot under the body, it can be put anywhere, and the knee as well. Where is the best position under the body? If the foot is placed improperly like to far in front the effect felt will be like walking up hill all day. If the foot is placed to far behind the effect will be like walking down a hill all day. Placed to close to the other foot under the body will cause the knee to get pushed outwardly with each step. If the foot is placed to far away from the other foot the opposite effect will occur. If the prosthetic limb is to short the other knee and hip can be strained and if it’s made to long, uncomfortable pressures will occur rapidly and nice cosmetic walking will become impossible.
Below the knee type devices have alienable systems that offer 12 independent adjustments and above the knee types offer 20 different adjustments. Artificial limbs are very complex. Correctly made devices offer restored balance and an opportunity to resume an active life style. If the prosthesis is not contributing to an improved quality of life for you or someone you know, get it fixed. Do not give up if you’re having problems, get it fixed. You are entitled to a properly fitting comfortable prosthesis!!!
This is an organization with a wealth of information on this subject: www.oandp.com
Any questions, just ask, it will be my pleasure to help.
