What is a prosthesis?

A prosthesis is an artificial prosthesis that is specially designed and assembled to make up for amputees or incomplete limb defects by using engineering techniques and methods, also known as “prosthetics”. Its main function is to replace some of the functions of the limbs, so that the amputee can restore a certain degree of self-care and work ability. It is applicable to amputees due to diseases, traffic accidents, industrial accidents, sports injuries, etc.

 

Classification of prostheses:

Prostheses can be classified by structure, function, assembly time, amputation site, power source, and selected materials. But the most commonly used classification method is to divide the upper limb prosthesis and the lower limb prosthesis according to the amputation site.

The materials used to make prostheses are mainly aluminum plates, wood, leather, plastics and metal mechanical parts. A good prosthesis must have the conditions such as good function, comfortable and convenient to wear, light and durable, and appearance similar to a healthy limb. Among the many prostheses we use, there are many different categories and names according to the purpose, location, and control system of the prosthesis. The following is a brief introduction to the frequently used and more advanced prostheses.
 

(1) Decorative upper limb prosthesis: This kind of prosthesis does not have the function of self-care for work and life. Its main function is to make up for the appearance of the upper limb and maintain the balance of the limb. It is mainly used for high upper arm amputation, shoulder joint disengagement, and shoulder girdle disengagement.
 

(2) Tool hand: It is specially designed and made for upper limb amputees, and it is mainly composed of two parts. One is the arm tube installed on the residual limb. The arm tube is fixed on the residual limb. The end of the arm tube has a decorative upper limb prosthesis: This kind of prosthesis does not have the function of self-care for work and life, and the main function is to compensate for the appearance and appearance of the upper limb. Maintain the balance of the limbs. Tool adapter. The second is a variety of labor tools and daily life tools, such as hammers, screwdrivers, knives, multi-purpose hooks and other labor tools, toothbrushes, spoons and other daily life tools. Through the adapter, various tools and living utensils can be replaced at any time according to needs, and to a certain extent, the patient's working ability and self-care ability can be restored. However, the tool hand does not have the normal physical shape of a person, and the range of use is also very limited.
 

(3) Traction-type mechanical prosthetic hand: This kind of prosthetic hand is also called motorized prosthetic hand and mechanical prosthetic hand, which is a substitute for human hand. This kind of prosthetic hand relies on the coordinated movement of the user's own residual limbs and healthy limbs to drive the traction cable, manipulate and control the opening and grip of the prosthetic hand, and realize the action of grasping the extracted object. This kind of prosthetic hand is mainly suitable for the disabled forearm and upper arm. Because it is simple in structure, reliable in performance, easy to master, easy to use, and low in price, it is more commonly used in China.

(4) Electric prostheses: Electric prostheses are externally powered prostheses, which rely on a small electromechanical drive system to complete the predetermined movements of each joint of the prosthetic hand, so that the disabled can basically take care of themselves and participate in appropriate work. This kind of prosthesis is suitable for forearm or even full arm defect.
 

The electric prosthesis is composed of three parts: an electromechanical drive system, a control system, and a shell. The electromechanical drive system relies on micro-batteries to provide energy, and the control system relies on touch-press microswitches to switch the circuit, and sends out control information to manipulate the electromechanical drive system to complete the action.