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3C88-3~23C98-3 - Knee prosthetics

C-Leg 4

Choose the latest in proven performance
With over 100,000 fittings to date, the C-Leg is trusted by more users than any other microprocessor knee in the world. 1 And it’s no wonder: Studies show the C-Leg provides the exceptional reliability and performance users need to focus on what really matters — enjoying a healthy, active lifestyle.(Wismer, N., Mileusnic, M., Sreckovic, I., & Hahn, A. (2016))From descending stairs and ramps, to navigating uneven terrain, to walking backward, the C-Leg dynamically adapts to a wide variety of everyday situations.This legacy lives on in the C-Leg 4 update. With an innovative design and exciting new features, the C-Leg 4provides the knownreliability, next-level personalization, and an easier, more intuitive user experience for both patients and professionals alike.1 Wismer, N., Mileusnic, M., Sreckovic, I., & Hahn, A. (2016). First results on next generation C-Leg. Poster presentation at OTWorld, Leipzig, German
Product typeMicroprocessor
Mobility grade2, 3, 4
Max. body weight300 lbs
All specifications
Benefits at a glance

Proven performance at every step

A user with the C-Leg leg prosthesis walking to work outside a glass-fronted office building.
More freedom of movement

The key to fluid movement is a knee that responds quickly to different inclines and surfaces. With the new C-Leg 4, users get improved stance release and increased support for descending ramps and stairs, enabling noticeably smoother and more reliable movement.

Enhanced safety
Stumble Recovery Plus

Stumble Recovery Plus is active at all times with the C-Leg 4 Update. This ultra-precise feature automatically detects fall-like movements during the swing phase of users’ gait and activates the resistance they need to avoid a fall, recover their balance, and maintain greater stability.

The C-Leg user is sitting at the kitchen table with her friend.
Support and comfort for sitting

The C-Leg 4 detects when users sit down, mirroring their speed to keep them stable and in control — even if they’re using a chair or a walking aid for support. Once seated, they can enjoy a relaxed, comfortable position with a free-swinging joint thanks to the automatic sitting function.

C-Leg 4
Enhanced user experience

Now it’s easier than ever for users to get the most out of their C-Leg. Deep sleep mode saves battery during long flights, camping, or other activities where power supply is limited. A redesigned charger enables one-handed use. Plus, there’s a USB charging adapter available.

Training feature
Helpful training function

A new training function provides a feedback signal after every successful swing phase initiation to support troubleshooting and gait training as users get accustomed to their prosthesis. This feature can be activated and deactivated by the prosthetist or user via the Cockpit app.

A family scene in the garden: The son is spraying his father with a hose as he descends the stairs with his C-Leg.
Weatherproof design (IP67)

With the C-Leg 4, users don't have to worry about occasional water splashes. Whether they’re walking past a sprinkler, working in the garden, or caught in a sudden rain shower, the C-Leg is designed to stay protected as long as the joint and components are dried off afterward.

MyMode Plus
MyMode Plus

Now, users can easily get more support for their favorite activities. MyMode Plus offers a fantastic selection of options for work, leisure, and athletics. Together with their prosthetist, users can select two settings for easy activation in the Cockpit app or via a movement pattern.

A C-Leg user is painting her shield insert
Customizable shield cover

Users can personalize the look of their prosthesis thanks to a new customizable shield cover. Not only do these robust, durable covers protect the C-Leg 4 from environmental factors, wear, and tear, they also now empower users to show off their unique style with each step.

The new colour of the C-Leg 4 – Midnight Shadow.
New color option

Many of the updates to our signature C-Leg microprocessor knee are based on feedback we received from users and professionals. In fact, that’s why the C-Leg 4 is now available in two colors: the original lighter Desert Pearl as well as a new darker shade, Midnight Shadow.

The C-Leg 4 activates his MyMode Plus in the Cockpit App
Smart control via app

With the Cockpit app, users can fine tune MyMode Plus and other settings individually, switch between MyMode Plus options, check their knee’s battery life, set their volume, track their activities, perform a knee joint self-test if needed, and much more — all via their iOS or Android smartphone.

A C-Leg user is standing in a paint shop
Stance function selection

With their prosthetist’s help, users can choose between intuitive and deliberate stance functions. Intuitive stance uses subtle cues to detect whether users need support for standing or taking a step, while deliberate stance requires more conscious movements to resume flexion.

O&P professional – laptop keyboard
More support for prosthetists

Featuring C-Soft Plus 1.10 software, the new C-Leg 4 offers even more preset options and video tutorials to assist professionals and users throughout the fitting process.

User Experience

C-Leg users enjoy healthy, active lives

Georg’s C-Leg 4 Story

Georg maintains an unwavering positive attitude toward life. In fact, he believes his amputation has created new possibilities for him, such as realising his childhood dream of skiing, discovering a passion for the javelin, and becoming a para-athlete. Watch the video to see how the C-Leg 4 supports him during sports, daily routines, and everything in between.

Rebecca’s C-Leg 4 Story

Rebecca loves to express creativity in every facet of her life. And thanks to the new custom shield cover for her C-Leg 4, her unique style and personality are always on display for the world to see. Watch the video to see how the C-Leg 4 keeps Rebecca focused on what really matters — not every step she takes, but rather where each step will take her.


See why more users trust C-Leg

Intelligent system

Ottobock is continually developing the C-Leg to ensure users get the latest and greatest in microprocessor knee technology. The C-Leg supports users throughout the entire gait cycle, adjusting to their unique walking patterns in real time. So, whether they’re going downstairs step-over-step, descending slopes, or navigating uneven terrain, C-Leg users can truly trust their prosthesis as they move through their daily activities.


Twenty-five years of continuous development based on real practitioner and user experiences have made C-Leg the most preferred and trusted microprocessor-controlled knee joint in the world. It’s also the most widely studied and proven. In fact, 77 scientific publications featuring upwards of 2,500 subjects clearly support the benefits that C-Leg users across the globe enjoy every day.


Thanks to innovative new developments, C-Leg 4 users enjoy more harmonious, fluid movement patterns — even when taking small steps, changing walking speeds, or navigating different types of terrain such as sand, grass, and gravel. Even users who have never worn a C-Leg are able to adjust to the prosthesis over a relatively short period of time.


Many studies have proven that users fall significantly less frequently with the C-Leg than with conventional prostheses, making the C-Leg one of the most reliable leg prostheses in the world. In addition, the new C-Leg 4 provides even greater safety and stability via Stumble Recovery Plus and increased support for sitting down.

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Learn More

An amputee trials the Ottobock C-Leg 4 at a prosthetists office

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Interested in giving the C-Leg a try? Please provide additional information and we will connect you with a partnered O&P professional for a trial.

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Product information

Product typeMicroprocessor
Mobility grade2, 3, 4
Max. body weight300 lbs
Amputation levelHip disarticulation, Transfemoral amputation, Knee disarticulation

Product Data

Article number3C88-3=8.5-23C98-3=8.5-23C88-3=9.2-23C98-3=9.2-2
Mobility grade2, 3, 42, 3, 42, 3, 42, 3, 4
Distal connection

Tube clamp

Tube clamp

Tube clamp

Tube clamp

Proximal connection

Threaded connector


Threaded connector


Knee flexion angle130 °130 °130 °130 °
Moisture protectionIP67 (weatherproof)IP67 (weatherproof)IP67 (weatherproof)IP67 (weatherproof)
Weight (without tube adapter)1255 lbs1,250 lbs1255 lbs1,250 lbs
Max. body weight300 lbs300 lbs300 lbs300 lbs
ColourMidnight ShadowMidnight ShadowDesert pearlDesert pearl
Proximal system height to alignment reference point26 ″5 ″26 ″5 ″
Minimum distal system height with 257/2R67 tube adapter289 / 329 ″289 / 329 ″289 / 329 ″289 / 329 ″
Max. distal system height with 257/2R67 tube adapter494 / 534 ″494 / 534 ″494 / 534 ″494 / 534 ″
Min. build height with 2R57/2R67 tube adapter297 + 9* / 337 + 9* ″294 / 334 ″297 + 9* / 337 + 9* ″294 / 334 ″
Max. build height with 2R57/2R67 tube adapter502 + 9* / 542 + 9* ″499 / 539 ″502 + 9* / 542 + 9* ″499 / 539 ″
Proximal build height to alignment reference point26 + 9* ″23 ″26 + 9* ″23 ″
Min. distal build height with 2R57/2R67 tube adapter271 / 311 ″271 / 311 ″271 / 311 ″271 / 311 ″
Max. distal build height with 2R57/2R67 tube adapter476 / 516 ″476 / 516 ″476 / 516 ″476 / 516 ″



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Since its launch in 2015, the Kenevo microprocessor knee fundamentally changed prosthetics for low to moderately active amputees. This prosthetic knee was designed to provide you with a greater sense of security so you can live the life you deserve. Microprocessor-controlled knees have been shown to reduce the risk of uncontrolled falls by up to 80%1 in moderately active persons, as well as improve the indicators of fall risk, such as fear of falling.2 With key features such as Stumble Recovery Plus, supported stand-to-sit and sit-to-stand, wheelchair mode, and putting on the prosthesis while seated, it is no wonder users feel more confident and independent than ever before.   1. Kannenberg, A., Zacharias, B., & Pröbsting, E. (2014).2. Mileusnic et al. 2017