There are different types of prosthetic leg knee prosthesis, and there are many varieties. The functions and performances they achieve are also different. The types of prosthetic leg knee prosthesis generally include mechanical knee joints, lockable knee joints, hydraulic knee joints, and pneumatic knee joints, smart knee joint, etc.
1. Mechanical prosthetic knee joints include single-axis knee joints and multi-axis knee joints.
The uniaxial knee joint is a prosthetic knee joint with a single axis of rotation. It has high flexibility in the swing phase, but it is not stable enough in the support phase. It is more suitable for young patients with long residual limbs who have a lot of activities and good control over the residual limbs.
Most of the multi-axis knee joints use a linkage mechanism, and the center of rotation is designed to move up and down, forward and backward in a wide range with the flexion and extension angle of the knee joint, and its flexibility is relatively poor. This kind of prosthetic leg knee prosthesis is suitable for patients with relatively small activities. , the functional level of the prosthesis is not very high, but the patients with high stability requirements.
2. Knee joints with locks include manual locking knee joints and load-bearing self-locking knee joints.
The manually locked knee joint looks stiff and clumsy, but it has very good security. It will be automatically unlocked at the beginning of walking. This kind of prosthetic leg knee prosthesis is very suitable for patients with weak control of the prosthesis and often on uneven ground. Active patients who walk on terrain.
The load-bearing self-locking knee joint uses body weight to apply pressure to generate resistance on the knee shaft to brake. The swing block of the knee joint is connected to the upper part of the joint body through the shaft, and connected to the lower part of the joint body through the shaft of the knee joint. Together, they form a locking device based on body weight, which ensures the safety and stability of the stance period. This prosthetic leg knee prosthesis is suitable for amputees with medium or low functional levels who do not like to use the locked knee joint.
3. Hydraulic knee joint. Due to the incompressibility of the fluid, the stance phase of the hydraulic knee joint is more stable and is more suitable for patients with high activity levels.
4. Pneumatic knee joint. Due to the strong compressibility of the gas, there is still a certain amount of compression after the valve of the pneumatic cylinder is closed, so its stability in the support period is slightly poor. The advantage of this prosthetic leg knee prosthesis is that it is lighter in weight and more flexible in the swing period. it is good.
5. Intelligent knee joint. The smart knee joint is a relatively new technology. It has many built-in sensors to detect the state of motion, and then automatically adjusts the control cylinder according to the state. This kind of prosthetic leg knee prosthesis reduces the learning cost that patients must pay for using the knee joint, and the gait is more natural. But they weigh more.
A good prosthetic leg knee prosthesis can ensure the stability of the patient in the stance phase and the flexibility in the swing phase, complete walking naturally, and enable the patient to have a good gait, which is also the determining factor for the performance and lifespan of the entire prosthesis.