30-Second Demonstration of the CIR Sand Casting System





Introduction: 30-Second Demonstration of the CIR Sand Casting System

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In only 50 seconds, the CIR Sand Casting System allows for the replication of a residual limb. This model can then be modified and used to create a final transtibial (below-the-knee) prosthetic socket. The technique eliminates the need for plaster bandages and Plaster-of-Paris, and requires only:

1. A large container
2. Silica sand
3. An air compressor capable of maintaining a vacuum
4. A metal pipe for connecting to vacuum pump
5. Thin plastic bags
6. Rubber bands

The contents of this presentation/publication were developed under a grant from the Department of Education, National Institute on Disability and Rehabilitation Research grant number H133E980031. However, those contents do not necessarily represent the policy of the Department of Education, and you should not assume endorsement by the Federal Government.



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    seeing it used with an amputee, start to finish would be nice. I would be concerned when it came to the vaccum with the limb in the sand

    I hope this site is still being moderated. It would be great if you could answer my question: If I understand correctly, the final positive cast is made of sand that is being held in shape by vacuum, and that presumably once the vacuum is cut off, the sand would just fall from the mandrel. How then is this cast used to fabricate a lamination? How is the vacuum maintained throughout the process of lay-up, etc.?

    Thanks so much for your questions!

    The positive cast is in fact made of sand and is contained within a second plastic bag. It is sealed in this bag using rubber bands and/or tape, making it possible to maintain the shape for a short period without vacuum applied - this also allows for modifications to the positive model if needed. After creating the positive model, the cast of the socket can be made using a draping method as would traditionally be done for a plaster positive model.

    The Forbes logo has to be displayed for at least 2 seconds, right?

    I just voted from the link on Facebook. I think this is very clever. Awesome. It seems very simple, almost too simple. Has this actually been used on a person yet?

    Thank you so much for voting!

    The CIR Sand Casting System was developed and tested in Chicago, and underwent independent evaluation in Hanoi, Vietnam in 2004. In 2005, the BMVSS-Jaipur Limb Program in Jaipur and New Delhi, India adopted the technology, which (as of 2007) was replaced by an improved version of CIR Casting System. Currently, this newer casting method is widely used in India and Thailand. A modified version of the CIR Casting System was used in Thailand to fabricate prostheses for two elephants who were injured by landmines.

    To date, the CIR Sand Casting System and the newer CIR Casting System have been applied to between 2,000 and 3,000 individuals with below-the-knee amputations.

    So this is a prosthetic leg made out of sand?

    Thank you very much for your question. This technique allows for the creation of a positive sand model of a residual limb that can then be modified and used to fabricate a prosthetic socket. It is designed to be used to replicate the residual limbs of individuals with lower limb amputations. The difference between the traditional plaster-based approach for creating a positive model and the CIR Sand Casting approach is that when the socket is made, a model made of plaster will require portions of the plaster inside to be chipped off (left) while with the sealed-sand model, the plastic bag can be cut open to drain the sand (center). De-molding the formed socket (right) with the CIR Sand Casting approach is rapid and safe.