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Contact us today for more information on RHEO KNEE 3, to schedule a fitting or apply for a tryout.

A perfect balance of stability and dynamics

RHEO KNEE 3 incorporates tried, tested and proven technology, along with a number of improvements to make life that little bit easier.

Stable enough for Ellie...




RHEO KNEE 3 offers increased and smoother resistance across a wider range of stance flexion.

This enhanced support from heel strike to toe off helps increase the confidence of all users on varied terrain, ramps and stairs.

This is especially reassuring to lower activity users like Ellie.

..dynamic enough for Tim.



We didn't sacrifice the swing dynamics that the RHEO KNEE is known for and that higher active users like Tim expect.

In fact, we improved them! By further reducing swing phase resistance, we made it even easier for higher activity users to walk their way and lower activity users to initiate swing.

Now, whether he is cycling, hiking, or working in the garage, Tim feels he "wastes" less energy getting around.

Dynamic gait with added confidence

RHEO KNEE 3 helps users to feel in control at all times and takes confidence to a whole new level:

  • Feel totally confident and safe, even on stairs, ramps and uneven ground
  • Change speed and direction with absolute ease
  • Move more naturally, even in confined spaces
  • Think less about what to do and how best to move
  • Walk farther, using less energy, and maintain an active lifestyle

The bonus for the average user is that it is ultra stable, while the more active person will benefit from the extra functionality.

"RHEO KNEE 3 is so stable and easy to walk on, and now I can ride it down ramps and stairs"

User Benefits

1Improved Actuator design

  • Unmatched response to gait and speed changes
  • Complete and constant responsiveness to different and changing circumstances
  • Increased maximum torque on stairs providing improved stability
  • Easy, natural swing motion

2Faster and more natural swing extension

  • Smooth and natural swing extension
  • Improved toe clearance translates to less risk of falling

3Upgraded Software Technology

  • Advanced control features continuosly monitor and adapt resistance levels

4Kinematic sensor

  • Added stability in non-gait movements
  • Accurate stand-to-walk transitions

5Improved User Profile

  • Battery autonomy up to 3 days
  • User weight limit increased to 136kg (300lbs)
"I loved my hydraulic MPK but now I'm able to do more each day while feeling less tired."

Appropriate for wider range of people

100 %
of the lower active users reported a higher feeling of safety
83 %
of all users had an increased walking distance with the 2MWT
82 %
of all users reported a higher feeling of comfort
100 %
of the lower active users improved their time on the L-test
67 %
of the higher active users improved their time on the L-test
39 %
average reduction on Borg scale after 2MWT

RHEOLOGIC Workbench

Reduce Your Reimbursement Risk

RHEOLOGIC Workbench is designed to improve your clinical documentation for payers and better manage your reimbursement risk. Document your RHEO KNEE user's true activity level by printing an Activity Report of data collected on the RHEO KNEE.

RHEOLOGIC Brochure (pdf)

RHEO KNEE's Gait Cycle

Inital Contact to Mid Stance

  • Generates optimal knee resistance, based on cadence and gait
  • Increased comfort and confidence of support across walking speeds.

Late Stance to Pre Swing

  • Easy and effortless swing initiation.
  • Enables smooth and natural walking in confined spaces, such as crowds or in the kitchen.
  • Ideal for low-to-moderate K2 walkers.

Mid Swing

  • Minimal swing phase resistance and immediate response to speed changes.
  • Automatic Stumble Recovery provides knee support to help users regain balance.
  • Helps reduce trips and falls, enhancing user confidence.
  • Super responsive and keeps up with speed changes like no hyraulic cylinder can.

Terminal Swing

  • Automatically adjusts swing resistance as walking speed varies.
  • No excessive terminal impact regardless of walking speed.

Contact us for more information

Product demo

CPO's, have an Ossur rep contact you to schedule a product demonstration or provide more information.

Try out!

Users, get in touch with us to explore your options of a free trial or locate a RHEO KNEE 3 certified practitioner near you.

More information

If you'd like more information on the characteristics and specs of RHEO KNEE 3, take a look at the product information page.

Product Page

For more information on how RHEO KNEE behaves at each stage of the gait cycle, download the Gait Cycle Information Sheet (pdf).

RHEO KNEE Gait Cycle (pdf)

For more information on the RHEOLOGIC WORKBENCH download RHEOLOGIC Brochure (pdf).

RHEOLOGIC Brochure (pdf)