NK-6 Symphony

The NK-6 Symphony Knee has a unique 6-Bar polycentric structure, providing a high level of stability in the stance phase. Its innovative mechanical sensor, the p-MRS system, automatically detects the walking status from the position of the centre-of-mass, and controls the stability of the knee joint accordingly. A hydraulic cylinder provides a smooth swing phase, and works with the NK-6’s adjustable stance flexion feature to enhance walking and provide a comfortable, confident gait to the user.

Features and benefits

p-MRS system

  • Polycentric-Mechanism of Reaction force Sensing system
  • Anticipates and adjusts to user's movements by monitoring the underfoot position of the ground reaction force
  • Prevents knee instability from heel-strike to mid-stance by locking knee geometrically
  • Naturally and smoothly releases from locking during pre-swing for transition into the swing phase

Adjustable stance flexion

  • Absorbs shocks at the heel-strike
  • Instantly locks to prevent sudden knee buckling while allowing slight flexion
  • Reduces centre-of-gravity displacement

Hydraulic cylinder

  • Eases the initiating swing, reducing initial knee flexion resistance
  • Decreases energy consumption compared to conventional hydraulic knee joints

Optional selective lock

  • Provides maximum stability whenever needed
  • Prevents knee buckling, whilst still allowing stance flexion in the lock mode


Weight limitBuild body heightDistal adaptorMaterialActivity levelWarranty
125kg156mmPyramidTitanium & aluminiumLow to medium (K2 to K3)2 years

Ordering information

Part numberNK-6NK-6LNK-6-SHNK-6-SH-L
Selective lockNoYesNoYes
Proximal adaptorPyramidPyramidScrew headScrew head
Product weight890g940g930g980g
Total build height197mm197mm191mm191mm


NK-6 Symphony Sales Sheet
NK-6 specifications
NK-6 Knee User Guide
NK-6 instruction manual

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