Put Your Best Foot Forward

You get big feet, small feet, white feet, black feet, clean feet and smelly feet! Just pulling your leg!

Prescribing a prosthetic foot for a patient is a bit more scientific than just picking the correct size and colour.

Shock absorption, energy return, load-bearing ability, flexibility, cost, activity level, weight, patients age, cosmetic finish, rollover behaviour, and materials are a few of the decisive criteria that must be fine-tuned to each patient’s individual needs.

Making a comparison of prosthetic feet according to the above criteria would be lengthy and confusing. In order to keep it simple I will compare only two products: the Sure Flex IV and the College Park Tribute as the activity levels and costs of both products are quite similar. 

Remember, any overseas product is only as good as its local agent and this should be one of the deciding factors in a Prosthetists product choice.

College Park Tribute The College Park Tribute

College Park Industries was incorporated in 1988 upon completion of the first Foot prototype. The company uses biomechanical design principles for the development and manufacture of a broad selection of prosthetic feet with anatomical function. College Park are the sponsors of the College Park Golf Cup in America.

The Tribute is one of the cheapest feet in their range and costs a patient about R14 903.00. The foot has a weight limit of 100Kg and is recommended for low to moderate impact levels, so mowing the lawn is about as active as you should get with this foot – according to College Park: “this foot gives the dysvascular population the mobility they require”.

The ankle offers movement in all directions (multi-axial) so it is ideal for uneven terrain and is also adjustable in all directions so it can be fine-tuned to a patient’s specific needs.

College Park Tribute Internal ViewThe foot shell is removable for replacement and cleaning and the building height is low, measuring only 6.1 cm, that is ideal for medium to long trans tibial stumps. The foot comes with a very handy rubber boot to keep the inside clean and it adds a nice cosmetic touch to the prosthesis for a patient that doesn’t want a cosmetic cover.

I have found this foot to be very durable, but despite that, they only carry a one year guarantee. The foot is not delivered with an alignment brochure. Alignment specifications are found in the product file that the supplier distributes to Prosthetists. If the local agent does not have stock it would take them approximately 5-10 days to order it from America.

It is evident that a lot of thought has gone into manufacturing this foot, attempting to make it anatomically functional.

Sure Flex IVSure Flex IV

Flex foot was introduced in 1984, invented by a prosthetic user named Van Phillips. On the WCA price list the Sure Flex IV was listed as a high activity foot whereas, in actual fact, it is only rated for low activities, so there are many of these feet out there being used and abused and coping very well. The Sure Flex IV foot stands at the bottom of the activity level scale as far as Flex feet are concerned. At the top end is the Cheetah Flex Foot that Oscar uses, so you can say it has a good pedigree.

This little foot has filled big shoes in the past. For years it has been the most affordable light-weight, carbon-composite, energy return foot on the market. At R10 430.00 it is also quite a bit cheaper than the Tribute plus Flex also offer a two year guarantee.

The foot also has a slightly higher weight limit of 136Kg and, whereas the foot shell is not removable, it is easy to clean with compressed air.

Flex Foot focuses a lot on energy return (spring action of the forefoot) and the Sure Flex has moderate energy return. This foot is ordered according to the patient’s exact weight and activity level.

Because of the flexibility of the carbon fibre blades the foot offers mild multi-axial movement at the ankle. The building height is 12cm so it might pose slight difficulties when fitting it to very long trans tibial stumps.

Flex Foot AssureIt is challenging to make a good cosmetic cover for this foot because the foot shell is soft and moves around a lot which, on the other hand, adds to the dynamics of the foot.

The technical support of the local agent is legendary and they always have stock of this particular product, so once ordered you should receive it within a day. They are also involved in various golf days locally.

Halfway through writing this article I learnt that the Sure Flex IV is to be discontinued and replaced (updated) with the, all new, Assure foot. This is exciting news; it should be a real knockout! My industry spies got a sneak preview!

Verdict

I like both these feet. The Sure Flex might be getting a bit long in the tooth but the new Assure should be fabulous.

The patient that tested the feet for me liked them both. He enjoyed walking on uneven terrain with the College Park and on even surfaces at differing speeds with the Sure Flex.

I would suggest that you ask your Prosthetist to see if he can get you a loan unit of both. By wrapping a foot in Glad Wrap you can walk with it for a day without damaging anything and feel the differences for yourself.

Please keep in mind that the manufacturers have other models in their product line-up to cater for various needs, so please visit the websites of College Park Industries (www.college-park.com) and Ossur (www.ossur.com) for more info.

         - Heinrich Grimsehl – Prosthetist Netcare Rehabilitation Hospital 011 489 1313

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