Flex-Foot® was invented by prosthetic user and research prosthetist/inventor Van Phillips. Two critical breakthroughs made this product unique and revolutionised the everyday aspirations of amputees.
The first, energy storage and release, is a function inherent in the patented carbon fiber design of Flex-Foot. The second, vertical shock absorption, enables a more natural gait and protects the sound limb and remaining joints of the amputated limb from excessive shock.
Today, different functions are available within the Flex-Foot range to suit individual needs. All models offer significant advantages over conventional prosthetic feet. Twenty years of scientific material research lead to this unparalleled design, making Flex-Foot the ideal choice for durability, comfort and performance.
Vertical forces generated at heel contact are stored and translated into a linear
motion described as Active Tibial Progression. This action reduces the need to
actively push the body forward using the contralateral foot and also equalizes
stride length.
Benefit: More natural gait and reduced walking effort.
The Carbon-X Active Heel stores the energy during loading response as the
amputee transfers his or her body weight onto the prosthetic foot. Energy
is gradually released from the heel providing optimal return for forward
progression of the limb.
Benefit: Reducing impact to the joints and residual limb thus increases comfort, reduces joint and limb damage.
The EVO (Energy Vector Optimization) feature is generated by controlling how the ground reaction force is transferred to the prosthetic foot. Each step is optimized through the magnitude, placement and direction of forces for maximum efficiency. EVO enables the amputee to develop the most natural gait progression possible which reduces fatigue and puts less pressure on the sound side.
Benefits:
Fluent roll-over which mimics natural gait progression
Reduced fatigue
Effortless control of the ankle during stance phase
Less pressure on the sound side
Less pressure on the lower back
The full length keel/toe lever matches the length of the sound foot, providing improved support to the prosthetic limb during late stance. It ensures that users spend equal time on the prosthetic foot and natural limb, thus providing improved walking dynamics and reduced impact to the sound limb.
Benefit: Improved walking symmetry and reduced impact to the sound limb.
Heel height can be adjusted for various types of shoes to ensure correct alignment. Users can easily change shoes to fit most occasions as the heel height can be adjusted within the given range.
Benefits: Adjustable heel height minimizes misalignment of the prosthesis thus reducing walking fatigue and discomfort experienced with poor alignment.
Multi-axial compliance of the foot provides improved ground contact during ambulation on uneven surfaces.
Benefit: Maintain balance, stability and comfort when walking on uneven surfaces.
The layering of carbon fibre, optimised through extensive computer analysis and mechanical testing, ensures that the deflection of the carbon fibre heel and forefoot components are proportional to the user’s weight and impact level.
Benefit: Customized construction optimizes walking efficiency thus reducing fatigue for the user.
Trunk rotation is essential for good gait dynamics. If rotation is limited by loss of joints and the prosthetic interface, gait dynamics and comfort are compromised. Rotational forces are translated to more proximal joints and to the residual limb. Rotary torque absorbing components assist in restoring rotation thus improving joint health, comfort and gait dynamics.
Sandal toe foot designs incorporate a split between the first and second toe.
Benefit: More anatomical look for increased visual appeal and more functional compatibility with sandal shoes.
A split toe feature allows the foot to adjust to uneven surfaces, allowing amputees to walk with stability and comfort on uneven ground.
Benefit: Helps to maintain balance, stability and reduces peak impact during loading.
The vertical shock pylon reduces impact to the residual limb, joints and lower back during daily activities. It also ensures a more energy-efficient gait by minimising vertical displacement of the centre of gravity.
Benefit: Protection of joints, the spine and stump by reduction of the shock loading.
- Prosthetic foot habituation time of a subject with unilateral fibular hemimelia - a pilot study. Marchinda D, Honeycutt J, Alderink
- Influence of prosthetic foot design on sound limb loading in adults with unilateral below-knee amputations. Christhopher M. Powers MS, Leslie Toburn, MS, Jacquelin Perry, MD , Edmond Ayyappa, MS, CPO.
- Dynamics of below-knee child amputee gait: a comparative analysis of the Flex-Foot and SACH foot. W. Oppenheim, T. J. Hart, Y. Setoguchi, R. F. Zernicke, K. Schneider. University of California, Los Angeles.
- Physiological comparisons during multiple speed walking of physically active persons with transtibial amputation versus nonpathological gait. Hsu M, Nielsen DH, Yack HJ, Shurr DG. University of IOWA.
- Physiological measurements of walking and running in people with transtibial amputations with 3 different prosthesis. Miao-Ju Hsu MA, PT, David H. Nielsen PhD, PT, H. John Yack PhD, PT, Donald G. Shurr Ma,PT, CPO.
- Physiological measurements of gait during walking and running in transtibial amputees with conventional versus energy storing-releasing prosthesis. Miao-Ju Hsu MA, PT, David H. Nielsen PhD, PT, H. John Yack PhD, PT, Donald G. Shurr Ma,PT, CPO.
- Below-knee amputee gait in stair ambulation. Leslie Toburn MS, PT, Gregory P. Schweiger MD, Jaquelin Perry MD, Christopher M. Powers MS, PT.
- Transfemoral amputee physiological requirements: Comparisons between SACH foot and Flex-Foot. Pamela MacFarlane PhD, David H. Nielson PhD, PT, Donald G. Shurr MA, PT, CPO, Kenneth G, Meier CPO, Rex Clark MPT, Janelle Kerns MPT, Michele Moreno MPT, Beth Ryan MPT.
- Below-Knee Amputee Gait in Stair Ambulation. Leslie Toburn, M.S.P.T., GregoryP.Schweiger, M.D., Jaquelin Perry, M.D. , Christopher Powers, M.S.P.T.
- Physiological Comparison of Active Persons with Transtibial Amputation Using Static and Dynamic Prosthesis versus Persons with Nonpathological Gait during Multiple-Speed Walking. Miao-Ju Hsu,MA,PT, David H. Nielsen, PhD.PT, John Yack PhD,PT, Donald D. Shurr, MA,PT, CPO, Suh-Jen Lin,MS,PT.
-Gait Comparisons for Below-Knee Amputees Using a Flex-Foot Versus a Conventional Prosthetic Foot. Pamela MacFarlane PhD, David H. Nielson PhD, PT, Donald G. Shurr MA, PT, CPO, Kenneth G, Meier
- Gait assessment of a below-knee amputee during ambulation with multiple types of prosthetic feet. Marthur GB, Nielsen DH, Shurr DG, Physical Therapie Program, The University of IOWA City, IA;
- Biomechanical Analysis of the influence of prosthetic feet on below-knee amputee walking. Andrew Gitter, MD, Joseph M. Czerniecki, MD, David M. DeGroot, BS.
- Physiological comparisons during multiple speed walking of physically active persons with transtibial amputation versus nonpathological gait. Hsu M, Nielsen DH, Yack HJ, Shurr DG. University of IOWA.
- Transfemoral amputee physiological requirements: Comparisons between SACH foot and Flex-Foot. Pamela MacFarlane PhD, David H. Nielson PhD, PT, Donald G. Shurr MA, PT, CPO, Kenneth G, Meier CPO, Rex Clark MPT, Janelle Kerns MPT, Michele Moreno MPT, Beth Ryan MPT.
- Biomechanical analysis of the influence of prosthetic feet on below-knee amputee walking. Gitter A, Czerniecke JM, Degroot DM.
-Perception of Walking Difficulty by Below-Knee Amputees Using a Conventional Foot Versus the Flex-Foot. Pamela MacFarlane, Ph.D., David Nielsen, L.P.T.,Ph.D., Donald G. Shurr, L.P.T., CO. Kenneth Meier C.P.