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The Cheetah is a custom-built, high performance carbon fibre foot designed primarily for sporting activities.

This is the optimal sprinting foot for both transtibial and transfemoral amputees. It attaches posterior to the socket, making it agile, strong and a proven performer for professional athletes around the world. 

Cheetah Features

Oscar Pistorius

Some people want to run before they can walk – and who can blame them! Össur understands what it takes to move freely and most fast, hence its range of high performance prosthetic feet for people who want to achieve.

Experience the comfort, power and agility that make up the building blocks of high energy activity. From chasing world records to jogging with the dog, Össur’s sports feet are renowned for keeping people moving.

Superior biomechanical expertise, combined with invaluable feedback from top athletes and active people, has helped guide the following designs. Watch them in action when Team Össur get on the field, and prepare to be inspired.

Flex-Foot Cheetah®

It has broken all manner of records and, like its namesake, the Cheetah runs like the wind. Just watch athletes like Marlon Shirley, Oscar Pistorius or April Holmes, all three of whom are world record holders who ran their way into the history books on the Cheetah. An agile sprinting foot, it is used mainly by people with below-knee amputations, but is also suitable for some above- knee users. The design captures the running characteristics of the Cheetah, the world’s fastest land animal. It replicates the big cat’s hind leg, whose foot extends and reaches out to paw at the ground while the large thigh muscles pull the body forward.

Comfort, power and agility

If you think Össur’s sports feet could help you achieve your sporting ambitions, discuss the different options with your prosthetist.





Flex-Foot Cheetah User Information
Amputation level: Transfemoral and Transtibial
Impact level: Sport
Max Patient Weight: 147kg (325lbs)

Flex-Foot Cheetah Product Information
Warranty: 12 month limited warranty.
Categories:  2-9
Sizes: One Size Per Category
Weight of foot: 512g (18.1oz)
Build height: 411mm (16 3/8")
Adapter Options: Lamination Connector

For almost 15 years, scores of dedicated athletes have been using Össur’s legendary prosthetic sprinting foot the Flex-Foot Cheetah to compete at every level of sport. Today, it is internationally recognized as the gold standard in sports feet for elite athletes with limb loss.

The technology used in the Flex-Foot Cheetah from Össur has existed since 1997, and has not experienced any significant updates since that time.

What is it?

The Flex-Foot Cheetah from Össur is a J-shaped, high performance sprinting foot. Made of light, but extremely strong carbon composite, this prosthetic foot is designed to store and release energy in order to mimic the actions of the anatomical foot/ankle joint.

Who is it for?

The Flex-Foot Cheetah from Össur was designed for all types of lower-limb amputees who wish to sprint at a competitive and/or recreational level. 

How does the Flex-Foot Cheetah work?

The Flex-Foot Cheetah from Össur is a passive prosthetic foot that uses patented carbon technology to efficiently store and release the energy produced its user while running. The shape, which resembles the hind leg of a Cheetah – hence the name – acts like a shock absorber and spring. The "J" curve is compressed at impact, storing energy as well as absorbing high levels of stress that would otherwise impact the user’s knee, hip, and lower back.  At ‘toe-off’, the "J" returns back to its original shape, releasing a percentage of the stored energy in the same way that the anatomical leg does and helping to propel the user forward.

The foot’s design incorporates extra layers of carbon at higher stress points, such as the apex of the "J" curve, and less carbon where more flexibility is needed, such as the toe portion. Importantly, the Flex-Foot Cheetah from Össur has no heel component. This ensures that the reaction of the foot accurately mimics that of an able-bodied runner by keeping the user on the "balls of their feet," as well as producing a quicker reaction from the loading response in comparison with traditional prosthetic feet.

What does this mean for the amputee?

Ultimately, the Flex-Foot Cheetah from Össur allows athletes to train harder and longer, which can help to support higher levels of performance. The smooth reaction and dampening effect of the foot allows the user to focus on the task at hand, and not on what the foot is doing.

Customization of the Flex-Foot Cheetah from Össur 

The carbon technology is sometimes customized for the user. The optimum thickness or stiffness of the foot is dependent on the user’s body weight, residual limb length and alignment of the foot in relation to running style. Customization can help optimize individual performance, as well as improving the durability of the foot. Prosthetists can also customize the toe shape and tread plate attached to the bottom of the foot, applying a spike plate from a sprinting shoe or the sole of a tennis shoe for example to assure traction and conformity to the running surface.

Is the Flex-Foot Cheetah a bionic foot?

No. Bionic limbs incorporate sophisticated technology such as sensors, microprocessors and motors that have the ability to supply powered movement and responses for the user, based on feedback captured throughout the gait cycle.

The Flex-Foot Cheetah from Össur is a passive prosthetic foot, which means it is limited to returning a portion of the energy stored during the loading phase of running. Studies have shown that the Flex-Foot Cheetah can return up to 90% of the load applied to it. In contrast, the anatomical foot/ankle/gastroc system can return up to 249%.