Hydraulic (mechanical) prosthetic knee
Prosthetic knee joint solutions without electronic control that aim to regulate the swing and stance phases during walking with mechanical or hydraulic resistance.
What is a hydraulic (mechanical) prosthetic knee?
A hydraulic or mechanical prosthetic knee joint is a prosthetic component that aims to regulate the forward swing of the leg during walking and the stance phase when weight is placed on the ground, without an electronic controller, by means of its mechanical structure and hydraulic resistance. The knee responds according to the user's movement and walking speed.
This group covers different designs, from single-axis knees offering constant resistance to hydraulic/pneumatic knees that adapt to walking speed to some extent. Which design is suitable is assessed by the specialist physician and team, taking into account the person's amputation level, muscle strength, activity level and general health.
Key functions
The headings below introduce the general functions of this component group; the contribution of each function to the person is assessed individually.
Mechanical stance stability
A mechanical structure intended to limit unintended bending of the knee during the stance phase aims to provide support while standing.
Hydraulic swing control
Hydraulic or pneumatic resistance aims to contribute to a more balanced gait by smoothing the forward swing of the leg.
Design open to speed adaptation
Some hydraulic knees are designed to adapt to changing walking speeds to a certain extent.
Manual lock option
Some models may have an option allowing the knee to be locked manually for additional confidence while standing.
Use without electronics
Designed to work without the need for a battery or charging.
Durable and simple design
Its mechanical structure with relatively few components is designed with different everyday conditions of use in mind.
Stance phase and safety
When using an above-knee (transfemoral) prosthesis, it is important that the knee does not bend unexpectedly while standing and taking a step. Hydraulic and mechanical knees aim to support this safety with structures that provide resistance during the stance phase. Appropriate settings and alignment are decisive for comfort and control.
- A mechanical structure intended to provide support during the stance phase
- Alignment and resistance settings adjusted to the individual
- Check-ups after use and adaptation when necessary
How it differs from microprocessor-controlled knees
Microprocessor-controlled knees aim to change resistance in real time by means of sensors and an electronic controller and usually require charging. Hydraulic and mechanical knees, on the other hand, carry out this regulation without electronics, through their mechanical structure. The two groups respond to different needs; there is no general rule that one is superior to the other.
Which approach is suitable is determined by a specialist physician's assessment, taking into account factors such as the person's activity level, lifestyle, balance and muscle strength.
Fit, adjustment and maintenance
Alignment
The alignment of the knee and prosthesis is adjusted individually for walking safety and comfort.
Resistance adjustment
Swing and stance resistance can be adapted by the specialist team according to the user's experience.
Regular check-ups
A check-up is recommended at certain intervals and whenever a change in function, a noise or a loss of comfort is noticed.
Frequently asked questions
Who is a hydraulic prosthetic knee suitable for?
Suitability is assessed individually by the specialist physician and team, taking into account the person's amputation level, muscle strength, activity level and requirements.
Does it need to be charged?
Hydraulic and mechanical knees do not contain an electronic controller; they are designed to work without the need for a battery or charging.
How does it differ from a microprocessor-controlled knee?
The main difference is how resistance is regulated: hydraulic knees do this through their mechanical structure, while microprocessor-controlled knees do it by means of sensors and an electronic controller. The suitable option varies from person to person.
How often are check-ups needed?
A check-up is recommended at regular intervals and whenever a change in function, a noise or a loss of comfort is noticed in the component.
Let's assess the suitable solution together
The choice of prosthetic knee is individual and is determined by a specialist physician's assessment. You can contact us for information.
ContactThis content is for information purposes; please consult your physician for diagnosis and treatment. Fittings are carried out at our licensed center locations in line with a specialist physician's prescription/medical report.
