Scientists believe that the hand is the most distinctive organ of the human body, and the human hand is the most perfect tool that nature can create. At the same time, the rehabilitation of hand amputation is also the most difficult problem to solve in the field of prosthetic rehabilitation, because the function of hand is obviously superior to the lower limbs. Human fingers are very sensitive, and can feel the vibration of only 0.00002 mm. However, there is a long way to go to achieve this effect in prosthetic rehabilitation. With the development of science and technology, the rehabilitation of hand amputation patients has also improved. At present, there are two main rehabilitation schemes of hand prosthesis, decorative and functional. So, how can patients with such prosthetic limbs use their prosthetic hands flexibly? Today, Xiaobian will explain to you what needs to be understood in daily use.

1) Decorative prosthesis, generally as long as the residual limb receives the cavity appropriately, the suspension device is not a problem, does not need training, but the first installer should learn to wear the method, passive wrist rotation, passive change the finger position method. The upper arm amputees should learn to use passive elbow locking.

2) Cable-controlled upper limb prosthesis and electric upper limb prosthesis (including electromyographic prosthesis) belong to functional prosthesis. The difference is that the former is self-motive force, while the latter is external motive force. In order to improve the use function of these prosthetic limbs, correct use guidance and training are needed.

1. Prosthetic limb training

When wearing, the residual limb is inserted into the access chamber, and then the prosthesis is inserted into the shoulder strap. The time-out sequence is reversed.

2. Prosthetic manipulation training

Open and Close Hand Training: The cable-controlled prosthetic hand is opened by forcing forward on both shoulders, while the prosthetic hand is closed by elasticity when not using force. The upper arm cable-controlled prosthetic hand can only be opened by locking the elbow joints. Forearm electromyographic prosthetic hand is often used by amputees to perform phantom limb movement by stretching their hands, stretching their wrists to control the opening of their hands, bending their fingers forcefully, and closing their hands by flexing their wrists.

(3) Prosthetic limb training: The function of the hand is a complex process of sensory feedback and muscle coordination. If the prosthetic hand function is really required to be of practical value, it must be carefully trained.

The electromyographic prosthetic hand is driven by a miniature direct current motor through a gear drive mechanism to assist the patient's hand movement. The characteristics of the device are as follows: two electrodes for collecting EMG signals are set to be attached to the active area of the EMG signals of the patient's arm, and the EMG signals representing the opening and closing of the fingers are collected respectively. The two electromyogram signals are input into the control module including the single chip computer and the motor driving circuit, and the single chip computer outputs the opening of the prosthetic hand. The closed signal drives the micro DC motor forward or reverse by the motor driving circuit, and closes or opens the prosthetic hand by the gear transmission mechanism, thus driving the patient's hand to open and close. Therefore, the most important point of flexible use of EMG prosthetic hand is to place the EMG sensor correctly in the strong part of EMG signal selected by the technician.