The present disclosure relates to the medical field and, more specifically to an orthotic device in the form of a moldable splint for immobilizing, embracing and supporting a body part, preferably comprising an articulation, of a human or animal. The present disclosure also relates to an orthotic system including the orthotic device and to methods of manufacture and use thereof.
Immobilization devices such as a cast, a splint, a brace (orthosis) and stiffening apparatuses are used to impart a desired position to a supported portion of the body or to immobilize the supported portion relative to other parts of the body. Traditionally, plaster casting materials have been used because they are very low cost. However, plaster casting materials are heavy and cannot be cleaned or easily removed. Recently, plaster casting materials have been replaced by synthetic casting materials which are lighter in weight and can be cleaned but have a rough exterior surface and are still relatively heavy and bulky.
Plaster materials are associated with important disadvantages such as its weight, the development of dust, the occurrence of sharp and hard edges, and the time required for its application. In addition, it is also often necessary that a cast or other immobilization device be removed for medical consultation or exercise by a therapist and then put back on the patient. The plaster material casts cannot be removed intact and put back on the patient.
Braces have been described which are made of a sheet material impregnated or coated with a curable resin. For example, a known orthopedic casting article comprises a flexible sheet material impregnated or coated with two different resins. The article may be in the form of an orthopedic casting tape or a protective pad comprising a fabric backing that is longitudinally impregnated or coated with two different curable resins, preferably water-curable resins. The orthopedic casts are made by providing a curable casting tape; initiating the cure of the casting tape, e.g., by exposing the casting tape to water; and allowing the casting tape to cure to form an orthopedic cast.
Another known orthopedic casting article comprises a curable resin (e.g., a water curable resin) and a filler (e.g., fibrous materials) associated with the resin. Yet another known orthopedic cast comprises a sheet formed of an open-celled foam sheet impregnated with a water curable resin. Upon activation of the resin impregnated foam sheet and molding the same around the body part, an orthopedic splint is formed.
However, a common drawback of the braces comprising a curable resin is that the curing process takes a considerably time, e.g., around 30 minutes or more, before an orthopedic cast functional enough to support the injury is obtained. Moreover, the curing process is irreversible and it is impossible to shape the cured cast or splint in another position. Therefore the cast or splint has to be changed, i.e., a a new cast or splint needs to be applied at different phases of the injury healing process. In addition, to supply the cast or splint a technician needs to wear gloves.
Another problem is that casting or splinting may be very difficult, especially when it is required to build casts having different angles, e.g., a 90° angle between the foot joint and low leg, since at the same time it is necessary to make sure that a good angle is obtained, that the lamination and pressure is optimal, and that contours are followed. Furthermore, a cast or splint like those available in the prior art, wherein the casting material consists of a water-curable resin, and/or currently used products such as synthetic casts and/or P.O.P. ((Plaster of Paris), have a cure (setting) time that can take more than one hour. During all that time the required casting position needs to be maintained, otherwise the casting material can lose the required position and it might be necessary to start all over again. It is very difficult to keep a patient for 30 minutes or more to up to one hour or more to sit still when he/she is in pain, or when he/she is, like most children, scared.
Thermoplastic materials are now being used for forming casts and braces and other immobilization devices. These thermoplastic materials can be produced in extruded sheets which, when brought to a melt point (50° C. to 100° C.), can be molded and manipulated to conform to and shape around a body part, such as a limb, and then allowed to cool to hardness. These materials can also be reheated, brought back to their original shape and then remolded into a different shape. Compared to other casting materials, the thermoplastic materials provide many advantages including simplicity of use and ease of cleaning.
A known thermoplastic apparatus for immobilization or support of a body part of a human or animal is formed from a sheet of thermoplastic moldable material that is substantially rigid at ambient temperatures and pliable at higher temperatures. The apparatus consists of two elements, which are fastened to one another by means of a fastener for fastening. The fastener is directly attached to the thermoplastic material, so that the fastener allows the thermoplastic apparatus to be removed from and put back on the human or animal body part.
However, a problem associated with the above-mentioned braces made of thermoplastic material is that they lack flexibility, and do not allow the injured body part to undergo slight movements, e.g. swelling. In addition, differences in pressure in the brace (orthosis), e.g., due to movements of a patient carrying the brace or due to swelling of the body part, may induce deformations or distortions in the brace configuration and/or create pressure contacts on the body part. In addition, application of the above-mentioned type of braces on impaired limbs, arms or other body parts, involves the adjustment and fastening of the fasteners to a patient, which is a time-consuming process. Another problem associated with this type of braces is that they are relatively heavy.
It has also been suggested to use cork-like material for manufacturing braces and the like. For instance, there is known a splint made of a disposable material containing a cork-like material such as EVA (ethylene vinyl acetate). However, a problem associated with such material is that it is not breathable. This is an important disadvantage, since for improving wound healing and for permitting better transpiration, it is highly recommended to use braces or the like which are capable of some oxygen/air diffusion. It has been shown in the art that braces that are not sufficiently breathable can cause skin irritation, skin maceration, or skin dryness.
Another problem with currently known braces made of softer materials is that the braces may be or become too soft once applied on a body part, and loose sufficient hardness. Such braces may easily bent or form folds or pressure contacts on the body part, which may result in injury or sub-optimal recovery of the injured body part.
In view of the foregoing, there is a need for an orthotic device and system for immobilizing, embracing and supporting a body part, preferably comprising an articulation, of a human or animal, and corresponding methods of manufacture and use thereof which overcome the foregoing drawbacks of the conventional art.
In a first aspect, the present disclosure relates to an orthotic device formed of a single sheet of moldable Polylactic Acid (PLA) material for embracing and supporting a body part of a human or animal comprising an articulation and configured to maintain the body part in an optimal position for development and treatment.
According to features of the present disclosure, the PLA sheet is breathable, light-weight, sanitary and moisture-resistant.
In one embodiment, the PLA sheet is formed with a plurality of perforations uniformly distributed over the total surface area of the PLA sheet. Preferably, the perforations are distributed over 75% to 95% of the total surface area of the PLA sheet.
In another embodiment, the PLA sheet has a thickness in the range of about 1.5 mm to about 5.0 mm, and more preferably in the range of about 1.5 mm to about 3.5 mm, and even more preferably in the range of about 1.8 mm to about 2.0 mm.
In other embodiments, the PLA sheet is breathable, light-weight, waterproof and recyclable.
In yet another embodiment, the PLA sheet is formed with at least one aperture for passage therethrough of a body part of the human or animal.
According to a feature of the orthotic device, the PLA sheet is pre-cut to a preselected configuration suitable for forming to shape for a custom application.
In another aspect, the present disclosure is directed to an orthotic system including the orthotic device according to any of the foregoing aspect and embodiments. In one embodiment, the orthotic system further includes an inner protective layer applied directly onto the body part, and the orthotic device is applied directly onto the inner protective layer. In one exemplary embodiment, the inner protective layer comprises a bandage. In another exemplary embodiment, the inner protective layer comprises a single moldable sheet of polyethylene foam. The orthotic system may further include a fastener for releasably securing the orthotic device onto the body part.
In yet another aspect, the present disclosure is directed to a method of forming a splint using the orthotic device according to the foregoing aspects and embodiments.
Still another aspect of the present disclosure relates to methods for manufacturing the orthotic device according to the foregoing aspects and embodiments.
The following detailed description of the embodiments of the disclosure will be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the disclosure, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the disclosure is not limited to the precise arrangement and instrumentalities shown.
The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the disclosure are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
It should also be understood that the terms “about,” “approximately,” “generally,” “substantially” and like terms, used herein when referring to a dimension or characteristic of a component of the present disclosure, indicate that the described dimension/characteristic is not a strict boundary or parameter and does not exclude minor variations therefrom that are functionally the same or similar, as would be understood by one having ordinary skill in the art. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.
In the embodiment shown in
According to a feature of the present disclosure, orthosis 1 is made of a thermoplastic material which is moldable (e.g., above 50° C.) and breathable. By this construction, when orthosis 1 is heated above a specific temperature it becomes flexible and can be adjusted to the unique skeletal characteristics of the body part to be treated. After orthosis 1 cools down, it becomes rigid again.
The term “flexible” as used herein, refers to a material which is able to adjust readily to different conditions and in particular refers to a material which is able to easily flex and/or bend without breaking.
As used herein, the term “breathable” refers to a material, which allows air to pass to some degree. Such materials keep out water, but also release perspiration/transpiration vapor. This term refers to materials that have been made breathable by means of human mediation, for instance by means of perforation. In this regards, in the present embodiment perforations 2 are provided in the sheet of thermoplastic material for breathability of orthosis 1 once in place on the patient, that is, perforations 2 permit ventilation of the patient's skin when orthosis 1 is in place upon the body part of the patient. Perforations 2 may also facilitate molding of the sheet when shaping the sheet into a splint on the patient. Preferably, between about 75% to about 95% of the total surface area of orthosis 1 is perforated, and for instance about 75%, about 80%, about 90% or about 95% of the total surface area of orthosis 1 is perforated. Perforations 2 are uniformly distributed over the total surface area of orthosis 1. As shown in
Another feature according to the present disclosure is that the orthosis may also be perforated to provide apertures for body parts, such as thumbs, toes, etc. in the embodiment of
According to another feature of the present disclosure, the thickness of orthosis 1 designated by reference numeral 4 in
As another feature of the orthosis according to the embodiment of the present disclosure, the thermoplastic sheet of material is formed of Polylactic Acid (PLA). While PLA is a thermoplastic material that allows for flexibility and adjustability, the use of PLA allows the orthosis according to the present disclosure to provide sufficient rigidity to the injured body part. The inventors of the present disclosure have discovered that PLA imparts a rigidity on the orthosis of the present disclosure that cannot be achieved by other types of thermoplastic materials, such as Polycaprolactone (PCL), particularly when the orthosis 1 has a thickness within the ranges described above. The flexible and adjustable nature of the PLA orthosis according to the present disclosure allows the injured body part to which the orthosis is mounted to undergo slight movements, e.g., swelling. The flexibility of the PLA material makes the orthosis of the present disclosure suitably deformable in order to conform to contours and the physical reactions of the treated body part (e.g. swelling/de-swelling) while not compromising the rigidity and hardness of the orthosis. Another advantage of using PLA for the orthosis according to the present disclosure is that PLA is a biodegradable, biocompatible, non-toxic and eco-friendly polymer.
Mechanical and material properties of PLA for the orthosis according to the present disclosure are provided below:
As a production process, there are two methods for manufacturing polylactic acid (PLA) from lactic acid: the first method uses the cyclic lactic acid dimer called lactide as an intermediate stage; the second method is direct polymerization of lactic acid. The method using the lactide intermediary yields polylactic acid (PLA) with greater molecular weight. This production process is described in the publication Fibre Chemistry Vol, 41, Nov. 6, 2009, by Ozan Avinc and Akbar Khoddami, which is incorporated herein by reference in its entirety.
Suitable PLA's for the orthosis according to the present disclosure include the following commercially available products:
As noted above, the thickness of orthosis 1 according to the present disclosure allows orthosis 1 to be lightweight but also as rigid as required. Advantageously, the orthosis according to the present disclosure is considerably lighter than prior art orthotic devices. For example, orthosis 1 according to the present disclosure preferably has a weight higher than 60 grams but preferably less than 180 grams.
Orthosis 1 according to the present disclosure, which is preferably made of a single flat sheet of pre-cut PLA material, may be shaped onto the patient's body part (i.e., the wrist) by applying heat using a heat source. In one embodiment, the heat source may be a heated water container 7 as shown in
According to another feature of the present disclosure, are inner protective layer is applied directly onto the patient's body part for protecting the body part from the heat applied by the heat source during the forming/molding process. In one embodiment, the inner protective layer is a bandage (e.g., as elastic bandage) that is applied onto the patient's body part in preparation for forming orthosis 1 on the body part. For example,
In an alternative embodiment, the inner protective layer (e.g., bandage) is not applied, and orthosis 1 is applied directly onto the patient's body part 6, as for example shown in
According to an embodiment of the present disclosure, orthosis 1 is initially formed so that it does not completely encircle the patient's body part. As shown in
During application of heat, as shown in
According to the present disclosure, various means are provided for applying the requisite compressive force to orthosis 1. In one embodiment, compression is applied to orthosis 1 by quickly wrapping an elastic band 11, as a fastener of the first type, around the warm and pliable orthosis 1 as soon as it is installed, as for example shown in
The application of orthosis 1 is completed on injured body part 6 by releasably securing orthosis 1 with a fastener. In one embodiment, one type of fastener may be in form of an elastic band such as described above for elastic band 11. For example, after being used to apply the requisite compressive force to orthosis 1 as described above, elastic band 11 may be completely applied and retained (i.e., is not removed) over orthosis 1 to secure orthosis 1 about body part 6 as shown in
It will be appreciated that the use of elastic band 11 or retaining strap 12 as the fastener allows orthosis 1 to be rapidly applied to and removed from injured body part 6 by increasing or decreasing the amount of overlap to more closely fit the injured body part. Alternatively, a plurality of retaining straps or other means for securing orthosis 1 relative to body part 6 are suitable without departing from the spirit and scope of the disclosure.
Orthosis 13 shown in
Orthosis 14 shown in
Orthosis 15 shown in
Orthosis 16 shown in
The structural features and advantages for orthoses 13-16 in
The flowchart in
The flowchart in
The flowchart in
The PLA splints manufactured by any of the foregoing methods according to the present disclosure exhibit the various preferred structural characteristics and advantages described above with reference to
At the start of the process (Step 50), orthosis 1 (splint) according to the present disclosure is first provided (Step 51). Orthosis 1 is provided as a kit to the individual, the orthopedic specialist, physician, technician, first responder or other entity. In certain embodiments as described above, the kit further includes an inner protective layer (e.g., elastic bandage 5) and a fastener (e.g., elastic band 11 or retaining strap 12) as describe above which, together with orthosis 1, defines an orthotic system according to the present disclosure. The appropriate kit type and size for the injured body part to be supported is selected. Depending on the kit type selected, the orthosis is applied on the protective layer (
In this embodiment, bandage 5 (
Once orthosis 1 is sufficiently heated and pliable, approximately 5-10 minutes, for example, it is mounted and molded onto injured body part 6 (Step 54;
The heated orthosis 1 remains elastic and pliable for several minutes at room temperature, generally long enough for one skilled in the art to form a physiologically conforming splint, but orthosis 1 may be subjected to the heat source at any time to effect additional small changes in the forming/molding of orthosis 1 on injured body part 6 (Step 55) and/or to restore elasticity and prolong working time. The physiological conforming splint is then allowed to cool at room temperature on injured body part 6 to complete the forming process (Step 56).
After formation of orthosis 1 on injured body part 6, bandage 5 is taken off (Step 57). This can be accomplished, for example, by cutting bandage 5 along overlap slit or opening 10 that is formed by overlap edges 1a, 1b of orthosis 1, as described above, and removing cut pieces of bandage 7 via opening 10 and/or aperture 3 (
When the technician is satisfied with the final shape and fit of the physiologically conforming splint, the formation of orthosis 1 is done (Step 56). Application of orthosis 1 onto injured body part 6 is completed by releasably securing orthosis 1 with a fastener as described above. For example, the fastener may be in the form of a retaining strap 12 as shown in
In the present embodiment, the PEF sheet is formed of a single, flat sheet of material which is pre-cut to a preferred configuration that may be later formed to shape for a custom application together with a corresponding orthosis according to the present disclosure. As the inner protective layer, the PEF sheet is used in this embodiment in place of the bandage as described above for the previous embodiments.
PEF is a durable (wear and tear resistant), semi-rigid and lightweight closed-cell material. As compared to open-cell foams, PEF exhibits strength, rigidity, and resistance to water and moisture. PEF is also resistant to solvents and petroleum products (including chemicals and grease), and its antimicrobial property inhibits the growth of mold, mildew, and bacteria (i.e., is impervious to mildew, rot and bacteria). As a resilient material, PEF returns to form after compression, while still yielding enough to provide cushion and security where it is needed. In addition to the foregoing, the inventors of the present disclosure have discovered that PEF is particularly suitable for orthopedics due to the following additional characteristics and properties:
Flexibility
Cushioning
Uniform cell structure
Dimensional stability
Tear/puncture-resistant
Temperature resistant between 60° C. and 90° C.
Thermally insulative
Naturally resistant to low fire that can be improved by a suitable formulation
Non-abrasive
Non-dusting
Odorless
Cost/labor efficient (cost effective and easy to fabricate)
Excellent in shock absorption & vibration dampening properties
CFC (Chlorofluorocarbons) free
Ozone friendly
Recyclability
Example properties for PEF are provided below:
PEF sheet 17 may be adhered to orthosis 1 using a suitable adhesive. For example, a surface of PEF sheet 17 on which orthosis 1 is applied may be coated with an adhesive an adhesive on which a peelable backing sheet is applied. During use, after PEF sheet 17 is applied on the patient's body part, the backing sheet is peeled off and orthosis 1 is attached to the surface of PEF sheet coated with the adhesive. Alternatively, orthosis 1 may be applied directly over PEF sheet 17 without using an adhesive.
It will be appreciated that retaining strap 12 as described above for the embodiment of
According to a feature of the present disclosure, PEF sheet 17 effectively protects the body part from the heat during the forming/molding process. In addition to protecting the body part from the heat applied by the heat source during the forming/molding process, PEF sheet 17 provides further capability to custom fit the orthosis to the particular body part of a particular patient. The inventors of the present disclosure have discovered that due to the thermal insulation property of PEF sheet 17, the splint (e.g., PLA sheet) remains moldable for more than 1 minute, providing sufficient time for medical professionals to mold the splint onto the patient's injured body part. Because of its rest properties, the resulting orthosis is waterproof and lightweight, as well as resistant to odors, bacteria, mildew and rot and with increased sock absorption and vibration dampening properties, among other properties and characteristic described above for PEF sheet 17.
In the splinting process of
The orthotic device according to the present disclosure may be provided in a relatively flat shape or generally in the shape for a specific body part, such as a wrist, ankle, knee or other body part as well as in general sizes, such as large, medium or small. The orthotic device may also be pre-formed in some cases to approximately fit the body part for trial of size or in the case where a more complex structure requires it. The orthotic device can then be heated and custom shaped as described above to specifically fit the body part that it is to support.
Due to its flexibility, healthcare professionals may easily fit the orthosis to the injured body part and adjust the angle by gently allowing the orthosis to conform to the contours of the injured body part. In addition, if necessary, by temporarily and locally heating the material of the orthosis, a required angle for rehabilitation (e.g. spasticity of forearm) may be easily achieved if required to adopt another desired position.
The orthosis according to the present disclosure is easy and fast to use since it is formed of a pre-cut single sheet of material. The orthosis is also reliable to use, due to its anatomical design, with a high level of patient comfort. During the healing process sometimes it is required to change the angle of the injured body part, and this can be achieved with the orthosis of the present disclosure because it can be reshaped a number of times (e.g., more than ten times) to adopt another required position. As such, the orthosis according to the present disclosure is reshapeable and reusable.
Furthermore, the orthosis of the present disclosure is easy and quick to install. The orthosis offers the advantage of being able to be easily and rapidly removed and reapplied to a human or animal body part. The orthosis can therefore be recycled during injury healing. Because the orthosis of the present disclosure is formed of a single sheet of material and not of two or more separate elements which need to be affixed to each other by one or more fastening means, a physiotherapist or physician may rapidly apply and remove the orthosis to/from the injured body part.
The orthosis according to the present disclosure is soft when heated in order to provide optimal wearing comfort to the patient. The orthosis is in particular very light, even three to four times lighter than conventional orthotic devices made of thermoplastic materials other than PLA. Additionally, the orthosis of the present disclosure is clean and free of dust, translucent for X-rays, can be heated and formed in situ onto the patient's body part, can be worn until complete recovery of the injured body part, and has improved resistance to abrasion as compared to conventional orthotic devices. Another advantages of the orthosis according to the present disclosure is that due to its design it lowers both the cost to manufacture and apply the orthosis on the patient's body part, as compared with prefabricated orthotic devices, for example.
Additional advantages are achieved when the orthosis formed of a PLA sheet according to the present disclosure is further used in combination with an inner protective layer formed as a PEF sheet as described above with reference to
In one embodiment, the orthosis as well as the PLA sheet according to the present disclosure can be fabricated in different colors (e.g., fluorescent colors) and sizes for both children and adults.
In another embodiment, various accessories can be used with the orthosis according to the present disclosure to make each unique. For example, decorative elements may be embedded in the sheet of orthosis material at a depth at which the decorative elements remain joined to the sheet when it is heated and molded into the orthotic shape. Various accessories can also be added to the orthosis (e.g., splint) after it is fully set.
In yet another embodiment, biometric sensors are incorporated onto the orthosis of the present disclosure to permit doctors to monitor various conditions, including temperature, blood flow, swelling sweating, and mechanical pressure applied by the orthosis. Information obtained by the biometric sensors can be transmitted to a hospital/doctor via the internet to allow monitoring of the patient's condition.
The orthosis according to the present disclosure provides a ready to use orthosis solution to healthcare professionals, as compared to conventional orthotic devices comprised of thermoplastic plates that need cutting and trimming in order to form the orthosis. For example, the process for forming and applying an orthosis using thermoplastic plates is both time consuming and cumbersome. It could take anywhere from 1 to 2 hours to form the orthosis because, among other things, the healthcare professional needs to cut the thermoplastic plates, form the plates into the patient's injured part, and trim all of the edges of the resulting orthosis, all before the procedure of applying the orthosis to the patient's injured part is started. In contrast, due to its unique construction, the orthosis according to the present disclosure can substantially reduce the time it takes to apply the orthosis on to the patient's injured body part. The ready-to-use nature of the orthosis according to the present disclosure substantially reduces the average application time required by healthcare professionals. Furthermore, unlike many comparable orthosis devices, the orthosis of the present disclosure is also reusable.
Moreover, the orthosis according to the present disclosure is ready for use anytime needed. The orthosis is not custom, so it can fit any patient. This feature allows doctors and nurses to spend their time more efficiently. Thus, the orthosis according to the present disclosure allows healthcare professionals to reduce their costs and limit their inefficiencies, whilst patients are provided with an excellent quality orthotic device.
The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but are to be accorded the widest scope consistent with the principles and novel features disclosed herein.
This application claims the benefit of U.S. Provisional Patent Application No. 62/693,971, filed on Jul. 4, 2018.
Number | Date | Country | |
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62693971 | Jul 2018 | US |