The problem with loads on non-weightbearing casts is that the flesh of the heel easily develops ulcers when contact over 5 pounds is applied. Applicant has found no notable solutions to this problem in the prior art.
This inventor arrived at this design as an orthopedist, in a Technician's capacity, over the course of 30 plus years of experience. It is a necessary improvement to the art of cast making.
This disclosure provides the methods for installing such an apparatus, and similar nonlimiting exemplary apparatuses.
What is needed and not found in the prior art is a method to install devices that prevent heel sores in non-weightbearing casts. This is done through braces that both redirect common forces and create awkward obstructions that discourage certain improper placements of the cast.
This disclosure provides a preferred method and alternate methods. These methods teach a user to install various apparati which are not claimed as a part of this specification. The methods can be used to install similar apparati that accomplish the same objectives. It is imperative to clarify that the braced cast is still a non-weightbearing cast, and that routine loading is still limited to nearly zero loading.
About the Apparatus and Similar Conceptual Nonlimiting Apparatuses
In the specification, the preferred loading of the casts discussed is zero pounds. However, to accommodate loads up to approximately 5 pounds, this method installs types of bracing that are helpful. LOADING OVER 5 POUNDS IS IN NO WAY IMPLIED OR RECOMMENDED BY THIS METHOD.
The solution herein disclosed redirects common axial forces from the heel area to points of contact above and points of contact forward of the heel. The primary embodiment includes two braces that protect the bottom and back of the heel from contacts. In an embodiment, the braces are secured to a finished leg cast. Securing is done by means that do not compromise the integrity of the finished cast by using fiberglass rolls, plaster or other methods familiar to those in the field of orthopedics.
The solution also discourages placement of the non-weightbearing cast in two general and improper positions. First is resting the weight of the body on the cast. The placement of a brace below the heel creates awkward, unbalanced loading on the cast and leg. Additional features are contemplated such as installing uneven braces, creating further awkwardness. Similarly, installing a brace behind the foot creates another awkward loading when resting the cast horizontally, with the toes up.
In this specification the word brace is considered synonymous with other terms used herein, including “bracket” and “spacer”. The finished assembly, produced using this method is also described as a “braced non-weightbearing cast”.
In this specification the concept of a cast is used as an exemplary application. One of ordinary skill in the art would see that this method would apply to bracing other non-weightbearing applications such as splints.
Common loading refers to loads that many cast wearers would apply to the heel in normal activities for an injured person. For example a forward force directed from the heel area toward the toes during the frequent placement of the cast horizontally aligned and resting on a horizontal surface—picture a coffee table. Other common loads include resting some amount of the wearer's bodyweight on a non-weightbearing cast, in a generally vertical loading where the ground contacts the cast at the heel, and applies a reactionary force upward along the leg and cast.
In the preferred embodiment, two braces are used on a single non-weightbearing leg cast. As a nonlimiting embodiment, any number of braces can be used from at least one, and up to an integral cap (also described herein).
In a nonlimiting embodiment, each brace is attached at 4 points including two points on the left side and two on the right. With multiple attachment points, it is possible to redirect common forces to any “best” part of the cast using eccentric torque loading instead of single mounting attachments. That is to say, the original design directs all forces to each point of attachment, with one attachment on either side. A better place to redirect a load is to the back of the ankle—along the Achilles. To redirect the load, the rear brace attaches with at least two points on either side of the ankle for at least 4 points total. Thereby, common forces would impact the brace and create a torque instead of a direct impact. To be clear, a single, common force applied to the cast in a direction toward the heel, would in turn be applied “off center” to multiple eccentrically located attachments, to create a torque around the braced cast assembly.
In an embodiment, there are two attachment points on each side, in the ankle area. The first attachment point is lower than the other—one toward the sole of the foot and the other higher in the ankle area—perhaps ½″ apart. The attachment points are also slightly (e.g. ¼″) offset forward and rearward. With this 4 point mounting, any common load directed toward the back of the heel would be received by the multiple attachment points unevenly—eccentrically. This would cause a torque and apply the force at the back of the leg or on the sole of the foot. With an alternative positioning of the 4 mounting points a common force and resulting torque could be applied wherever is best.
An alternative embodiment that is installed by the method herein disclosed comes from the objective of the device—to prevent contact at the heel. The idea is to add an audible “click” at the brace to notify the wearer that a load of more than 5 pounds has been experienced by the cast. The click should reset—spring loaded perhaps—so that it is repetitive, notifying the wearer of his/her many 5# overloads. The intent is to be disruptive, and to create an incentive to avoid overloading the cast.
Another alternative embodiment speaks to children—who are notorious for overloading the cast at the heel. It is important to reiterate that: LOADING OVER 5 POUNDS IS IN NO WAY IMPLIED ENCOURAGED OR RECOMMENDED BY THIS METHOD. The suggestion is to install attachments or to install reshaped braces with decorative and aesthetically appealing, but functional brace designs. As an example, floral shapes of suitable size, shape and material can be attached as part of the method. As another example, the braces themselves may be formed from the supplier with pair of ears shape and a tail shape. In another example, the reshaping elements are formed and attached to the braces at the factory, or the same elements can be attached to the braces by the practitioner.
Another embodiment continues to use electronics that would allow both notice that an overload has occurred and there is an aesthetic advantage for younger wearers. Again: LOADING OVER 5 POUNDS IS IN NO WAY IMPLIED, ENCOURAGED OR RECOMMENDED BY THIS METHOD.
In an embodiment, Other electronics include a molded pressure pad with at least one pressure sensor that respond to 5 # loading. Schmersal sms4-500-500 is an exemplary pressure mat with about 244 sensors. This would be overkill, but offers the concept of a low profile mat with multiple input sensors. In this application, only 4 to 6 sensors are needed in a minimal arrangement.
In an embodiment, in place of the braces, a single molded cap is installed using the methods herein disclosed, and used as a shield around the entire heel area. Again: LOADING OVER 5 POUNDS IS IN NO WAY IMPLIED, ENCOURAGED OR RECOMMENDED BY THIS METHOD. The cap would secure to the cast similar to the braces—at two opposite sides of the heel. The cap, however could be closer to the cast than ¼″ previously outlined. The installer of the cap can install a seal around the edges of the cap, to seal the cap to the surface of the cast. This seal can also be made of a rigid material sufficient to create a ring of contact between the cap and the cast where the redirected forces would be applied along a sizeable contact area. In an embodiment, the method includes installing caps that have electronic switches and lighted outputs that mount and operate similar to those previously discussed. A familiar and similar concept is used to protect a broken nose from contact (often used for basketball). In this exemplary concept, the mask redirects any forces away from the nose area and to other parts of the face. One of ordinary skill in the art would be familiar with materials appropriate to the application, including but not limited to plastics, carbon fiber and metal.
In an embodiment, a direct force testing system is employed and installed using the disclosed method. This embodiment would be useful as a test mechanism or in applications that required the accurate measurement of the forces applied to a cast and in turn applied to the leg and foot of the patient. Force sensing pads (for example a pair of pads electronically connected by a normally open switch) are used at force transfer contact points and molded onto the cast by applying an additional pad at the places where the load is more optimally applied. The concept of a broad, soft pad at the heel was rejected because it could result in undesired contact and a resulting ulcer. However, the top of the foot, the bottom sole of the foot and the back of the ankle are mentioned herein as good places to direct/redirect forces. At these locations an applied force can be measured properly. An installer places the force pad is placed in contact with the cast (or even inside the cast to the cast liner or to the foot/leg) at the best points for measuring redirected contact forces—and then secures to the completed cast as needed. Force pad readings are communicated using direct wiring or externally mounted wireless devices.
Certain nonlimiting embodiments are outlined herein, and one of ordinary skill in the art would be aware of modifications or alternatives that would be similar. One of ordinary skill in the art would also be aware of tools and hardware to aid in the installation process, and would use such items to brace, stabilize, locate, prepare, install, secure and similarly apply the methods herein disclosed.
In the 300 attachment concept, application of forces is usually along eccentric axes. When these forces are applied, there is a resulting torque. This torque, in turn realigns and displaces the force to impact points that are remote from the heel. As a result, the installer of this 4 point brace should be aware of the resulting impact points and may provide padding or reinforcement to accommodate the resulting forces.
For embodiments using electrical features, battery holders must be installed and secured by methods obvious to anyone familiar with the art. For this type of bracing the mechanism should be tested before and after installation using a load of an appropriate weight, for example a 5# weight. The reset mechanism should also be tested. The mechanism should be demonstrated for the user, parents or other available responsible person.
The drawings provided are exemplary to demonstrate the details shown. The shapes, orientations, materials, modifications, alternatives and substitutions that are obvious to one of ordinary skill in the art are included. Further, tools and alternative fastening systems are also contemplated by the inventor and this specification. Finally, the shape of the braces are contemplated as rounded, eccentric, triangular, and others.
This specification claims the benefit of the prior filed provisional application No. 62/894,696.