Echelon 61 Small (1)

Hydraulic Ankle Technology

Advanced Technology Can Advance Functional Ability

It is common for health services to prescribe inexpensive devices with restricted function to limited community walkers.

Prosthetic interventions that are specifically designed for the biomechanical requirements of the older user could help reduce the risk of falls, maintain greater mobility and independence, improve quality of life and help reduce the long term burden on health care services.

Hydraulic Ankle Technology

Conventional prostheses are usually firmly attached to the shin or ‘pylon’ and rely on the deflection or deformation of polymeric foot components to replicate the dorsiflexion and plantarflexion behaviour of the natural ankle.

Models of the biological foot have shown that this elastic behaviour is present at normal walking speeds43. However, at slow speeds, the ankle becomes a net absorber of energy and the elastic model no longer fits43. The viscoelastic behaviour of hydraulic ankles better replicates natural ankle biomechanics.

Hydraulic Ankle Reduction in Pressure

Hydraulic ankle technology has been proven to provide a number of benefits to elderly amputees. During walking, the deformable components of a prosthesis are deflected when loaded and return to their original position when unloaded.

With a hydraulic ankle, when unloaded, the ankle joint remains in a dorsiflexed position, meaning that the toe clearance during swing phase is increased by 18%44 so there is less chance of catching the foot on the ground or another object and a trip occurring.

The damped motion of the ankle joint also absorbs energy and reduces the loading on the residual limb within the socket. One study measured reductions in peak pressures by up to 81% and in the rate of loading by up to 87%, during a number of different everyday activities45.

Hydraulic prosthetic ankles seek to mimic biological ankle action with a hydraulically-damped, articulating joint in combination with the deformable foot.

Hydraulic Ankles - Patient Benefits Overview

Biomimicry Allows for Safer Movement

Blatchford hydraulic ankles respond to the design specifications that natural movement dictates, fine-tuning joint position to align the body for optimum posture and comfort.

By continuously adjusting to absorb and release energy, our hydraulic ankles allow for an efficient roll-over, remaining perfectly aligned with the user for the next step to help reduce the risk of falls.

Biomimetic Foot Design

The best prosthesis replicates the dynamic and adaptive qualities of natural limb movement. This approach has resulted in the design of the world’s first hydraulic ankle-foot and award-winning technology by the Blatchford team.

Avalonk2 (1)

Avalon K2

AvalonK2 is our biomimetic hydraulic ankle that has been designed specifically for the complex needs of limited community ambulators. For K-2 level patients.


Avalon K2VAC

AvalonK2VAC combines the award winning AvalonK2 biomimetic hydraulic ankle with an integrated elevated vacuum system. This combination offers K2 users a unique product that both improves safety and long term health, and increases the feeling of socket security. For K-2 level patients.

Echelon (1)


The award-winning Echelon is a waterproof hydraulic ankle that absorbs and damps on impact, self-aligns on rough and sloping surfaces, then remains dorsiflexed at toe-off. These design features help reduce abnormal pressures at the socket interface and other joints, promote comfort and postural symmetry to help reduce the risk of falls and preserve musculoskeletal health. For K-3 level patients. PDAC approved for the USA.

Echeloner (1)

Echelon ER

Featuring an all-new robust and waterproof design, the extended range provides users with even more ground compliance on steep slopes and uneven terrain. Combined with improved accommodation of heel height, users have greater flexibility with footwear choice and a seamless transition to barefoot walking is possible.

Echelonvt 2018 Right

Echelon VT

EchelonVT combines the advanced hydraulic technology of Echelon with an additional rotation and vertical shock absorption element, to reduce the shear forces at the socket interface. This means the user is able to move and adapt more freely, making EchelonVT ideal for taking part in activities such as golf and hiking.

Echelonvac (1)

Echelon VAC

By harnessing natural ankle motion, EchelonVAC quietly creates elevated vacuum, helping to maintain an optimally fitting socket throughout the day.

Elan (1)


Elan is a microprocessor foot that mimics natural muscle resistance and ankle motion by adapting hydraulic resistance levels to optimise stability when standing and walking, on slopes and uneven terrain.

Elanic (1)

Elan IC

ElanIC is the world’s lightest and most compact waterproof microprocessor hydraulic ankle.

Hydraulic Ankle Technology Cover

Hydraulic Ankles

Clinical Evidence

Over a decade after challenging conventional wisdom, new scientific evidence continues to be published on the medical advantages of hydraulic ankles.

Clinical Compendium Cover

Clinical Compendium

Blatchford Biomimetic Hydraulic Technology mimics the dynamic and adaptive qualities of muscle actuation to encourage more natural gait.

Multiple independent scientific studies, comparing Blatchford hydraulic ankle-feet to non-hydraulic feet, have shown:

  • Greater comfort, reduced socket pressures
  • Improved safety, reduced risk of trips and falls
  • Smoother, easier and more natural gait
  • More evenly balanced inter-limb loading
  • Greater satisfaction
Orion Angle



A microprocessor controlled hydraulic knee with intelligent speed control.


• Situational Awareness – senses movement and speed to respond accordingly, in real time.
• Enhanced Stability Performance – 5 levels of stance resistance 
    - Controlled Stance Support
    - Standing Support
    - Dynamic Slope and Stair Descent
    - Stumble Recovery
    - Supported Sitting
• Natural Efficient Motion - MPC pneumatics ensure smooth swing at multiple speeds
    - Optimal Stance Release
    - Adaptive Speed Control
    - Terminal Swing Damping
• Cycling Mode and Fixed Angle Flexion Lock Mode
• Knee Flexion to 130°
• Intuitive Programming Software via PC or App
• Lithium Ion batteries with up to 3 days life
• Battery Life Indicator and Low Power Mode

Hydraulic Ankle Technology

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