Manufacturing and Prescription Protocols at RX Laboratories

Our range of custom-made foot orthotic devices has been designed by Ray Anthony. They represent a collection of the most biomechanically efficient, and aesthetically pleasing, foot orthoses available. Please visit our on-line catalogue to review the specifications of the full range by clicking here.

RX Laboratories uses the best shell materials available.

The devices in our ELITE range use TL-2100®, the only 100% graphite composite shell material available. Unlike other shell materials on the market that have been taken from other industries, TL-2100® has been specifically designed and manufactured for foot orthotic fabrication. It is the most researched, tried, and tested composite shell material available.

TL-Silver®, the latest continuous fibre composite matrial from Performance Materials Corporation, Inc., USA features in our PREMIUM range. In this range, you can get a pair of advanced composite orthotic devices for the same price as a pair of plastic devices at other laboratories. Our paediatric functional orthosis - the RX Child™ - has a TL-Silver® shell.

All of the devices in our ECONOMY range have high-density co-polymer polypropylene shells, including the RX Stride™ (adult functional), the RX Step™ (sports device), and the RX Cobra™ (slim-fit). Polypropylene shell are light, but retain high impact resistant properties.

The RX protect™ device, for diabetics has a low density EVA shell.

Due to the high quality of the shell materials used at RX Laboratories, all custom-made foot orthoses carry a lifetime warranty against shell fracture.

The most common posting materials we use are: dental acrylic (Methylmethacrylate), and high density (70-80 Shore A) EVA. We do not manufacture devices with acrylic posts on polypropylene shells as they avulse within a short period of time. EVA posts on sports orthoses may be supported with nylon post plugs to prolong the life of the prescription, and all EVA posts are covered with 1.0mm polypropylene, thin synthetic suede, or 1.0mm EVA post protectors.

High grade vinyl is used to cover our range of custom-made foot orthoses, although leather is available on request. 1.0mm EVA may be used as a top cover if a "non-slip" top surface is required.

RX Laboratories will manufacture custom foot orthoses to your individual specifications; however, our standard fabrication protocols are as follows:

For the sake of prescription accuracy, we recommend the use of intrinsic cast balancing for forefoot correction; although extrinsic forefoot posts are available on request. Intrinsic forefoot balancing is degree-for-degree accurate, avoids post avulsion, and makes for a lighter device: important for athletes requiring sports orthoses.

When polypropylene shells are pressed over casts with intrinsic forefoot correction, an EVA forefoot fill is applied to support the contours of the distal aspect of the shell, which limits shell distortion that may compromise of the forefoot correction. Please note that this is not a true post as there is no wedge incorporated. This method of forefoot 'control' is used on our unique range of polypropylene sports orthoses. The one exception in the sports range is the Trackstar™ device that has an extrinsic, sulcus length, EVA forefoot post.

Four methods of rearfoot correction are available at RX Laboratories:

An extrinsic acrylic or EVA post is added to the inferior aspect of the heelcup to promote orthosis stability, and to allow the incorporation of an accurate degree of 'pronation skive' or 'post motion' into the post. A properly applied acrylic extrinsic rearfoot post is biplanar on the frontal plane and both of these planes are accurately 'pitched' on the sagittal plane for correct shoe fit.

An EVA rearfoot post has only one frontal plane that is also pitched on the sagittal plane for correct shoe fit.

The inferior aspect of the heel of the positive cast is ground to zero degrees on the correct degree of pitch ('elevation'). A flat area is therefore produced in the heel cup portion of the orthosis shell. This flat plane replaces, and functions similar to, the medial plantar plane of an extrinsic acrylic rearfoot post, adding some stability to the shell during mid-stance.

The inferior aspect of the orthosis heel cup is ground to zero degrees on the correct degree of pitch (or 'elevation'). A flat area is produced under the heel cup portion of the orthosis shell. This flat plane replaces, and functions similar to, the medial plantar plane of an extrinsic acrylic rearfoot post, adding some stability to the shell during mid-stance. NB. TL-2100™ devices can be manufactured with this rearfoot correction incorporated.

For the sake of adequate rearfoot function, some prescriptions require the heel of the positive cast to be cut off and re-positioned in relation to the forefoot, thus changing the angle of the heelcup in relation to the supporting surface.

All fabrication methods and prescription protocols used at RX Laboratories are supported by published articles and research papers, ensuring a strong evidence base for our custom-made foot orthotic devices. The following established protocols are available individually or combined if required:

To ensure prescription accuracy and to guarantee a TRUELY custom-made product, we do not use computer aided design or manufacturing processes (CAD/CAM). All devices are manufactured over original cast impressions of the foot, and not computer generated images.

protocols.pdf