System Knee Joints

for Producing a KAFO (Knee Ankle Foot Orthosis)

Upon choosing a system knee joint, you get to pick one of three different functions: free moving, automatic or locked. Within each function, each system joint has different features, alternative functions and adjustment possibilities.

To use the automatic knee joint systems NEURO MATIC and NEURO TRONIC, you need a personal certification. Thereby, we can ensure that orthopaedic technician and patient have been trained in how to use the knee joint systems. Here you can find the dates of the certification workshops.

For an optimum selection of system components based on patient data, we recommend using the Orthosis Configurator.

Free Moving System Knee Joints and Articulated System Side Bars

NEURO CLASSIC zero System Knee Joint

The NEURO CLASSIC zero system knee joint is a free moving, monocentric joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The bumping noises are minimised by extension stop dampers. The NEURO CLASSIC zero system knee joint additionally provides a small posterior offset.


Manual NEURO CLASSIC zero system knee joint
Catalogue pages NEURO CLASSIC zero system knee joint
Online tutorial “KAFO Joint Lamination Technique”

NEURO VARIO zero System Knee Joint

The NEURO VARIO zero system knee joint is a free moving, monocentric joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The bumping noises are minimised by extension stop dampers. The NEURO VARIO zero system knee joint additionally provides a small posterior offset.

Furthermore, it is possible to limit the range of motion in extension as required by exchanging the extension stops.


Manual NEURO VARIO zero system knee joint
Catalogue pages NEURO VARIO zero system knee joint
Online tutorial “KAFO Joint Lamination Technique”

NEURO CLASSIC System Knee Joint

The NEURO CLASSIC system knee joint is a free moving, monocentric joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The bumping noises are minimised by extension stop dampers. Through an integrated posterior offset, it provides secure standing.


Manual NEURO CLASSIC system knee joint
Catalogue pages NEURO CLASSIC system knee joint
Online tutorial “KAFO Joint Lamination Technique”

NEURO VARIO System Knee Joint

The NEURO VARIO system knee joint is a free moving, monocentric joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The bumping noises are minimised by extension stop dampers. Through an integrated posterior offset, it provides secure standing.

Furthermore, it is possible to limit the range of motion in extension, as required, by exchanging the extension stops.


Manual NEURO VARIO system knee joint
Catalogue pages NEURO VARIO system knee joint
Online tutorial “KAFO Joint Lamination Technique”

NEURO ACTIVE System Knee Joint

The NEURO ACTIVE system knee joint is a free moving, polycentric joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. Through its integrated posterior offset, it provides secure standing.

Furthermore, it is possible to limit the range of motion in extension and flexion, as required, by exchanging the stops.


Manual NEURO ACTIVE system knee joint
Catalogue pages NEURO ACTIVE system knee joint
Online tutorial “KAFO Strong Light Technique”

NEURO ACTIVE Articulated System Side Bar

The NEURO ACTIVE articulated system side bar provides motion control and a free moving, polycentric joint. The articulated system side bar is pre-assembled in a physiological joint angle of 5°. It provides secure standing through its integrated posterior offset.

Furthermore, it is possible to limit the range of motion in extension and flexion, as required, by exchanging the stops.

The system side bars form u single unit with the system joint. Thus, you do not have to order or mount them separately.


Manual NEURO ACTIVE articulated system side bar
Catalogue pages NEURO ACTIVE articulated system side bar
Online tutorial “KAFO Strong Light Technique”

Automatic System Knee Joints

NEURO MATIC System Knee Joint

The NEURO MATIC system knee joint is an automatic joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The system joint is controlled mechanically through the plantar flexion aided by the system ankle joint. It has no electronic components. When the system joint is delivered, it is set on Auto mode. Alternative functions are provided by the Lock and Free mode. The mode can be manually switched by the patient with a lever on the system joint.

  • Auto mode: The system joint is automatically locked or unlocked.
  • Lock mode: The system joint is permanently locked.
  • Free mode: The system joint is permanently unlocked.

Furthermore, the NEURO MATIC system knee joint can be converted into a NEURO TRONIC system knee joint by exchanging specific system components.


Manual NEURO MATIC system knee joint
Patient information NEURO MATIC system knee joint
Catalogue pages NEURO MATIC system knee joint
Leaflet NEURO MATIC/NEURO TRONIC system knee joints
Online tutorial “NEURO MATIC System Knee Joint”

NEURO TRONIC System Knee Joint

The NEURO TRONIC knee joint system consists of the following components:

  • system knee joint,
  • component set including controller (optionally with integrated lithium-ion battery or exchangeable batteries),
  • remote control for the patient (optionally with microprocessor-controlled quick charger or USB charging cable),
  • multi-purpose device for the orthotist including batteries.


The NEURO TRONIC system knee joint is an automatic joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. Moreover, it offers an electromechanical automatic stance phase control. When standing with the orthosis, the stance phase control is not achieved mechanically but through the integrated posterior offset and the patient's remaining function of the hip and knee extension muscles.

The NEURO TRONIC is the first system joint in the FIOR & GENTZ range that can be controlled via a Bluetooth connection. This requires a multi-purpose device, a controller and a remote control with Bluetooth. You can order these, as well as the standard devices without Bluetooth, via the webshop after the configuration has been completed.

After purchasing a multi-purpose device with Bluetooth, you can install the free NEURO TRONIC Expert app on one or multiple mobile devices of your choice and use the app to set up your orthosis. Patients can use the NEURO TRONIC User app to switch between the individual modes, just like they would do with the remote control.

When the system joint is delivered, it is set on Auto mode. Alternative functions are provided by the Lock and Free mode.

  • Auto mode: The system joint locks and unlocks automatically.
  • Lock mode: The system joint is permanently locked.
  • Free mode: The system joint is permanently unlocked.


The system joint can also be unlocked mechanically. The patient can unlock it with the lever of the system joint. To change the modes with the remote control or the app, the system joint must not be mechanically unlocked.

In Auto mode, the NEURO TRONIC system joint can be activated by the sensor technology e-Motion. The system joint is controlled by motion sensors integrated in the controller of the orthosis.


Manual NEURO TRONIC system knee joint
Manual NEURO TRONIC multi-purpose device
Patient information NEURO TRONIC system knee joint
Catalogue pages NEURO TRONIC system knee joint
Leaflet NEURO MATIC/NEURO TRONIC system knee joints
Online tutorial “NEURO TRONIC in e-Motion”

Locked System Knee Joints

NEURO LOCK System Knee Joint

The NEURO LOCK system knee joint is a locked joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The patient can unlock the system joint with its lock lever.

Furthermore, the NEURO LOCK system knee joint offers various alternative functions:

  • Alternative Function 1: With accessory parts, it is possible to achieve a locking in different flexed positions. For this, it is necessary to exchange the extension stops and to adjust the system joint by filing the joint's lower part.
  • Alternative Function 2: In addition, it is possible to convert the NEURO LOCK system knee joint from a locked into a free moving, monocentric system joint with integrated posterior offset by removing the locking parts.



Manual NEURO LOCK system knee joint
Catalogue pages NEURO LOCK system knee joint
Online tutorial “KAFO Joint Lamination Technique”

NEURO LOCK MAX System Knee Joint

The NEURO LOCK MAX system knee joint is a locked joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The patient can unlock the system joint with its lock lever.  Furthermore, the NEURO LOCK MAX system knee joint offers various alternative functions:

  • Alternative Function 1: With accessory parts, it is possible to achieve a locking in different flexed positions. For this, it is necessary to exchange the extension stops and to adjust the system joint by filing the joint's lower part.
  • Alternative Function 2: In addition, it is possible to convert the NEURO LOCK MAX system knee joint from a locked into a free moving, monocentric system joint with integrated posterior offset by removing the locking parts.

Temporarily, the system joint can also be used as a free moving system joint.  Then, the lock lever is fixed with a pin. This function, including its reversion, can be switched by the patient any time.


Manual NEURO LOCK MAX system knee joint
Catalogue pages NEURO LOCK MAX system knee join
Online tutorial “KAFO Joint Lamination Technique”

NEURO FLEX MAX System Knee Joint

The NEURO FLEX MAX system knee joint is a locked joint, which provides motion control. It is pre-assembled in a physiological joint angle of 5°. The patient can unlock the system joint with its lock lever.
Furthermore, the NEURO FLEX MAX system knee joint offers various alternative functions:

  • Alternative Function 1: With the accessory parts, the system joint can be locked in different flexed positions. To do so, it is necessary to exchange the extension stops and to adjust the system joint by filing the pre-assembled flexion stop disc.
  • Alternative Function 2: In addition, it is possible to convert the NEURO FLEX MAX system knee joint from a locked into a free moving, monocentric system joint with integrated posterior offset by removing the locking parts.
  • Alternative Function 3: With the accessory parts, a step lock function with locked flexion can be integrated into system joint. This can be achieved by mounting a step lock stop disc and a step lock pawl.

    Note: There is always the option to order the NEURO FLEX MAX system knee joint with its already assembled Alternative Function 3. To order Alternative Function 3 right away, select the NEURO FLEX MAX system knee joint (pre-assembled Alternative Function 3) in the joint overview. Select also the system width you need.

  • Alternative Function 4: With the accessory parts, it is also possible to limit the maximum knee flexion angle. Therefore, an AF4-specific flexion stop disc and cover plate must be mounted to the system joint. As for Alternative Function 1, this alternative function also enables the system joint to lock in different flexed positions. For this, it is necessary to exchange the extension stops, to adjust the system joint by filing the flexion stop disc and to mount the specific cover plate.

Temporarily, the system joint can also be used as a free moving system joint. Then, the lock lever is fixed with a pin. This function, including its reversion, can be switched by the patient any time.


Manual NEURO FLEX MAX system knee joint
Catalogue pages NEURO FLEX MAX system knee joint
Online tutorial “KAFO Joint Lamination Technique”