SE541344C2

SE541344C2 - Method for production of an openable orthopaedic cast

Info

Publication number: SE541344C2
Application number: SE1650484A
Authority: SE
Inventors: Paul Ipsen; Per Flink; Thorleif Strand
Original assignee: Paul Ipsen; Per Flink; Thorleif Strand
Priority date: 2016-04-11
Filing date: 2016-04-11
Publication date: 2019-07-23
Also published as: SE1650484A1

Abstract

The present invention discloses an orthopaedic cast (1000) for functional support in secondary casting, comprising a resealable cast opener (100) and a support element (1050). The support element (1050) defines an inner space for the encompassment of a bodily part of a patient, and the surfaces of the upper side and the lower side of a first pre-adhesive sheet (111) of the resealable cast opener (100) and the surfaces of the upper side and the lower side of a second pre-adhesive sheet (112) of the resealable cast opener (100) being mechanically adhered to or within the support element (1050). Methods for production of the orthopaedic cast (1000) of the invention are also disclosed.

Description

METHOD FOR PRODUCTION OF AN OPENABLE ORTHOPAEDIC CAST TECHNICAL FIELD The present invention relates to orthopaedic casts, more particular to methods for production of openable and resealable ortopaedic casts for functional support in secondary casting.

BACKGROUND In common medical practice, immobilization of a bodily part, e.g. an arm or leg, is achieved by casting and/or splinting in order to facilitate the healing process of the related injury or medical condition and to prevent further medical complications. In an acute phase, splints are preferred for primary immobilization in comparison to rigid cast due to inflammatory swelling of the tissue. In a non-acute phase, rigid or semi-rigid casts provide suitable means for secondary immobilization and for functional support. Secondary immobilization by casting is technically more challenging than splinting and requires a high degree of experience and craftsmanship among the practitioners. Various devices and methods have been developed to facilitate secondary immobilization, following either primary immobilization or a first secondary immobilization.

Delta-Cast® casting tapes and stripes by BSN Medical, which may be used for secondary casting, consist of knitted substrates impregnated with a polyurethane resin. The casting is conducted by wrapping the tapes and/or stripes around a bodily part, followed by curing by exposure to ambient humidity or water. Casts of this type may be cut open and fully or partly removed from the bodily part, e.g. for inspection or treatment of the skin, followed by closure and wrapping with straps, e.g. Velcro straps, to provide subsequent means for mechanical support.

Disadvantages of this type casts include the limited control of distribution of pressure by wrapping with straps after partial or full removal from the bodily part, whereby the degree of pressure on specific sub-regions needed for medically optimal immobilization becomes insufficient.

Rebound® Air Walker by ÖSSUR, which may be used for secondary casting, comprises rigid elements having a geometry and curvature adapted to fit the bodily part being casted. Upon casting, these elements are linked together by straps to provide mechanical support to the encompassed bodily part. Internal air chambers, which may be operated by the user, are additionally provided to control internal pressure on regions of the surface of the encompassed bodily part.

Disadvantages of this type casts include the limited control of distribution of pressure by internal air chambers, which often fail to provide the degree of pressure on specific subregions needed for medically optimal immobilization.

In view of at least above mentioned disadvantages, improved methods for production of orthopaedic casts and related supports, e.g. openable and resealable orthopaedic casts or related supports, for use in medical applications, e.g. secondary casting, are needed.

SUMMARY It is an object of the invention, considering the disadvantages mentioned above, to provide a method for production of an orthopaedic cast that is openable and resealable to permit facilitated inspection and cleaning of the bodily part which is compassed within the cast in its sealed, i.e. closed, state.

It is another object of the invention, to provide a method for production of an orthopaedic cast that is openable and resealable to permit facilitated physiotherapy and/or rehabilitation exercises of the bodily part which is compassed within the cast in its sealed, i.e. closed, state.

It is yet another objective of the invention, to provide a method intended for medical personnel for the provision of an orthopaedic cast that is openable and resealable.

It is yet another objective of the invention, to provide a method for production of an openable and resealable cast which may be opened and resealed by the patient wearing the cast, without substantial assistance by medical personnel.

These and other objects, which will appear from the following description, have now been achieved by a method for production of an orthopaedic cast for immobilization of a bodily part of a patient by functional support in secondary casting, the orthopaedic cast comprising a resealable cast opener and a support element, wherein: the resealable cast opener comprising a central zip-fastener with a zip-fastener handle for user controlled closure and opening of the zipfastener, a first pre-adhesive sheet and a second pre-adhesive sheet; the central zip-fastener having a first zip-fastener half and a second zip-fastener half being mechanically attached, essentially along its full longitudinal extensions, to one edge of the first pre-adhesive sheet and to one edge of the second pre-adhesive sheet, respectively; the resealable cast opener exists in one state selected from the group of states consisting of an open state, in which open state the first zip-fastener half and the second zip-fastener half are fully separated from direct mechanical contact with each other, a partially open state, in which partially open state the first zip-fastener half and the second zip-fastener half are partially separated from direct mechanical contact with each other and simultaneously partially reside in a constant spatial relationship relative each other along the longitudinal extension of the first zip-fastener half and the second zip-fastener half, and a closed state, in which closed state the first zip-fastener half and the second zipfastener half fully reside in a constant spatial relationship relative each other along the longitudinal extension of the first zip-fastener half and the second zip-fastener half; the surfaces of the upper side and the lower side of the first pre-adhesive sheet and the surfaces of the upper side and the lower side of the second pre-adhesive sheet being adapted, by being provided with a pre-adhesive composition, to mechanically adhere to a support element when activated by an activation event; the activation event being a user controlled activation event comprising at least one of the group of activation events consisting of removal of protective physical matter from the pre-adhesive composition, addition of an organic or inorganic compound to the pre-adhesive composition, which organic or inorganic compound initiates a chain of chemical reactions leading to the formation of covalent chemical bonds between the first pre-adhesive sheet or the second pre-adhesive sheet and the support element when being in contact with each other, and exposure of the pre-adhesive composition to electromagnetic radiation, which electromagnetic radiation initiates or increases the rate of chemical reactions leading to the formation of covalent chemical bonds between the first pre-adhesive sheet or the second pre-adhesive sheet and the support element when being in contact with each other; the support element being a bent structure comprising a first limiting longitudinal end and a second limiting longitudinal end, essentially facing towards each other, and the support element defining an inner space for the encompassment of the bodily part of a patient; the surfaces of the upper side and the lower side of the first pre-adhesive sheet of the resealable cast opener and the surfaces of the upper side and the lower side of the second pre-adhesive sheet of the resealable cast opener being mechanically adhered to or within the support element to provide the first zip-fastener half of the resealable cast opener in an essentially constant spatial relationship relative the first limiting longitudinal end of the support element, and the second zip-fastener half of the resealable cast opener in an essentially constant spatial relationship relative the second limiting longitudinal end of the support element; and the method comprising the steps of: (i) providing the bodily part with an inner layer of the support element; (ii) applying the resealable cast opener, being in the closed state, on the outer surface of the inner layer; (iii) providing the inner layer and the resealable cast opener of step (ii) with an outer layer of the support element, to achieve placement of the resealable cast opener between the inner layer and the outer layer; (iv) activating the preadhesive composition by performance of the activating event, prior to step (ii) or after step (iii) or partly prior to step (ii) and partly prior to step (iii), to provide mechanical adherence between the upper side and the lower side of the first pre-adhesive sheet, the upper side and the lower side of the second pre-adhesive sheet with the inner side of the outer layer, the outer side of the inner layer, the inner side of the outer layer and the outer side of the inner layer, respectively; (v) cutting through the outer layer along the extension of the zip-fastener of the resealable cast opener, to expose the zip-fastener; (vi) setting the resealable cast opener in the partially open state or in the open state, to partially expose the inner layer; (vii) cutting through the inner layer along the extension of the open part of the zip-fastener of the resealable cast opener; and (viii) setting the resealable cast opener in the closed state.

Further features of the invention and its embodiments are set forth in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects, features and advantages of which the invention is capable will be apparent and elucidated from the following description of non-limiting embodiments, . reference being made to the accompanying drawings, in which Fig. 1 shows a resealable cast opener 100 in a partially open state, comprising a rectangular first pre-adhesive sheet 111 and a rectangular second pre-adhesive sheet 112, being joined together edge-to-edge by a central zip-fastener 120 of a closed proximal end type with a zip-fastener handle 129, via a first inner sheet 127 and a second inner sheet 128, respectively, in which the first zip-fastener half distal ending 125 of the first zip-fastener half 121 and the second zip-fastener half distal ending 126 of the second zip-fastener half 122 are spatially separated from each other, and the first zip-fastener half proximal ending 123 and the second zip-fastener half proximal ending 124 are residing in a constant spatial relationship relative each other, according to one embodiment; Fig. 2 shows the resealable cast opener 100 of Fig. 1 in a closed state, in which closed state the first zip-fastener half distal ending 125 and the second zip-fastener half distal ending 126 are residing in a constant spatial relationship relative each other, according to one embodiment; Fig. 3 shows an orthopaedic cast 1000 arranged for providing support and protection of the right arm and hand 510 of a patient, in which the orthopaedic cast 1000 is comprising a support element 1050 with an inner soft layer 1200 being in immediate contact with the patient’s skin, and a resealable cast opener 100 in a closed state with its first pre-adhesive sheet 111 and its second pre-adhesive sheet 112 mechanically integrated within the physical matter of the support element 1050, according to one embodiment; Fig. 4 shows the orthopaedic cast 1000 of Fig. 3 in a partially open state exposing a wound 520, according to one embodiment; Fig. 5 shows the orthopaedic cast 1000 of Fig. 4 without the resealable cast opener 100, with a first limiting longitudinal end 1061 and a second limiting longitudinal end 1062 of the support element 1050, which are essentially facing each other, according to one embodiment; Fig. 6 is a de-mounted partial view of an orthopaedic cast 1000 showing, in order from the outside towards the inside of the inner open space of the orthopaedic cast 1000, an outer semi-rigid layer 1102 of a support element 1050, a first pre-adhesive sheet 111 of a resealable cast opener 100, an semi-rigid inner layer 1101 of the support element 1050, and a soft layer 1200 for contact and protection of the skin of a bodily part of a patient, according to one embodiment; Fig. 7 is a partial view of a resealable cast opener 100 in an open state, comprising a zip-fastener 120 of an open proximal end type, according to one embodiment; Fig. 8 A shows the surface of a support element 1050 facing the surface of a preadhesive sheet 111,112 of a resealable cast opener 100, comprising a pre-adhesive composition 115 in the form of an adhesive paste or glue covered with a protective film 116, which support element 1050 and resealable cast opener 100 are mechanically separated from each other prior to the activation by an activation event, according to one embodiment; Fig. 8B shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 8 A being mechanically attached to each other after the activation by an activation event comprising the steps of removal of the protective film 116 and allowing contact between the surface of the support element 1050 and the thus exposed pre-adhesive composition 115, according to one embodiment; Fig. 9A shows the surface of a support element 1050 comprising hook-shaped semiflexible extensions facing the surface of a pre-adhesive sheet 111,112 of a resealable cast opener 100, comprising a pre-adhesive composition 115 in the form of a plurality of hook-shaped semiflexible extensions covered with a protective film 116, which support element 1050 and resealable cast opener 100 are mechanically separated from each other prior to the activation by an activation event, according to one embodiment; Fig. 9B shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 9A being mechanically attached to each other after the activation by an activation event comprising the steps of removal of the protective film 116 and allowing contact between the surface of the support element 1050 and the thus exposed pre-adhesive composition 115, according to one embodiment; Fig. 10A shows the surface of a support element 1050 comprising hydroxyl groups, attached thereto via -X-W-linkage, being in contact with the surface of a pre-adhesive sheet 111,112 of a resealable cast opener 100, comprising a pre-adhesive composition 115 in the form of isocyanate groups, attached thereto via -Y-Z-linkage, which support element 1050 and resealable cast opener 100 are devoid of substantial mechanical connection in the form of covalent chemical bonds between each other prior to the activation by an activation event, according to one embodiment; Fig. 10B shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 10A being mechanically attached to each other by covalent chemical bonds, comprising carbamate groups, after the activation by an activation event comprising the step of provision of a chemical catalyst or initiator, according to one embodiment; Fig. 11 A shows the surface of a support element 1050 comprising isocyanate groups, attached thereto via -Y-Z-linkage, being in contact with the surface of a pre-adhesive sheet 111,112 of a resealable cast opener 100, comprising a pre-adhesive composition 115 in the form of hydroxyl groups, attached thereto via -X-W-linkage, which support element 1050 and resealable cast opener 100 are devoid of substantial mechanical connection in the form of covalent chemical bonds between each other prior to the activation by an activation event, according to one embodiment; Fig. 11B shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 11 A being mechanically attached to each other by covalent chemical bonds, comprising carbamate groups, after the activation by an activation event comprising the step of provision of a chemical catalyst or initiator, according to one embodiment; Fig. 12A shows the surface of a support element 1050 comprising isocyanate groups, attached thereto via -Y-Z-linkage, being in contact with the surface of a pre-adhesive sheet 111,112 of a resealable cast opener 100, comprising a pre-adhesive composition 115 in the form of isocyanate groups, attached thereto via -Y-Z-linkage, which support element 1050 and resealable cast opener 100 are devoid of substantial mechanical connection in the form of covalent chemical bonds between each other prior to the activation by an activation event, according to one embodiment; Fig. 12B shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 12A being mechanically attached to each other by covalent chemical bonds, comprising urea groups, after the activation by an activation event comprising the step of provision of water as a chemical reagent, according to one embodiment; Fig. 12C shows the support element 1050 and the pre-adhesive sheet 111,112 of Fig 12A being mechanically attached to each other by covalent chemical bonds, comprising carbamate groups, after the activation by an activation event comprising the step of provision of a diol HO-L-OH as a chemical reagent, wherein “L” is a linker group, according to one embodiment; and Fig. 13 shows a resealable cast opener 100 in an open state, comprising a first preadhesive sheet 111, having an irregular lateral edge, and a second pre-adhesive sheet 112, having an irregular lateral edge, being separated from each other by a fully open central zip-fastener 120 of an open proximal end type, according to one embodiment; DETAILED DESCRIPTION Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings (Figs. 1 to 13) in order for those skilled in the art to be able to carry out the invention. The invention 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 invention to those skilled in the art. The embodiments do not limit the invention, but the invention is only limited by the appended patent claims. Furthermore, the terminology used in the detailed description of the particular embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention.

The openable orthopaedic cast 1000 of the invention essentially comprises a resealable cast opener 100 and a support element 1050. The resealable cast opener 100 thereof is mechanically attached to the support element 1050 in order to form a functional unit. When the cast opener 100 of the openable orthopaedic cast 1000 is closed, i.e. existing in a closed state, the support element 1050 provides adequate support for the bodily part, e.g. an arm or a leg, encompassed by the openable orthopaedic cast 1000. In such a closed state, a first zip-fastener half 121 and a second zip-fastener half 122 fully reside in an essentially constant spatial relationship relative each other along the full longitudinal extension of these. In the corresponding open state or partially open state, i.e. when the cast opener 100 is fully or partly opened, the support of the bodily part is fully or partly decreased, whereby the openable orthopaedic cast 1000 may be fully or partly removed from the bodily part. In the open state, the first zip-fastener half 121 and the second zip-fastener half 122 are essentially fully separated from direct mechanical contact with each other. In the partially open state the first zip-fastener half 121 and the second zip-fastener half 122 are partially separated from direct mechanical contact with each other and simultaneously partially reside in a constant spatial relationship relative each other. Transition from the closed state to the open state or the partially open state, followed by transition from the open state or the partially open state to the closed state, may be accomplished by a user, e.g. a patient or medical personnel, repeatedly a plurality of times, e.g. 5 to 100 times, such as 5 to 20 times. Advantageously, the present openable orthopaedic cast 1000 thereby enables facilitated inspection and/or treatment of the encompassed bodily part as compared to traditional casts of the prior-art. For example, the skin hidden under the openable orthopaedic cast 1000 in its closed state, may be inspected and potentially treated in a suitable way by the enabling sequence of transition from the closed state, via the open- or partly open state, and back to the closed state. Furthermore, the bodily part may be subjected to periodic physiotherapy to minimize the risk of undesired effects on tendons and ligaments during the casting period by the same enabling sequence.

The present resealable cast opener 100 essentially comprise a central zip-fastener 120, constituted by the first zip-fastener half 121 and the second zip-fastener half 122, and preadhesive sheets or fabrics, i.e. a first pre-adhesive sheet 111 and a second pre-adhesive sheet 112, each attached to the respective opposite longitudinal edge of the zip-fastener 120, such that they are mechanically separated from each other when the zip-fastener 120 is opened and mechanically joined together when the zip-fastener 120 is closed. A zip-fastener handle 129 may typically be attached to the slider of the zip-fastener 120 to provide maneuverability by a user. Selection of a suitable zip-fastener 120 is readily understood by the skilled person. A suitable zip-fastener 120 may, for example, be made of a radiolucent polymeric material with a relatively mechanical strength to allow x-ray examination of the encompassed bodily part and simultaneously permit sufficient mechanical support of the same in its closed state. The surfaces of the pre-adhesive sheets or fabrics are provided with a suitable pre-adhesive composition 115 which, upon an activation event and when brought in close contact to the support element 1050, becomes mechanically connected to the same. Non-limiting examples of such pre-adhesive compositions include suitable glues known in the art, which may be activated by removal of a protective film, Velcro type mechanic interaction element, which may be activated by removal of a protective film, and compositions comprising chemical groups which, upon activation by e.g. provision of electromagnetic radiation or addition of a chemical reagent or catalyst, reacts with corresponding chemical groups of the support element 1050 to form covalent chemical bonds between the pre-adhesive sheets or fabrics and the support element 1050.

In similarity to traditional casts, the support element 1050 is a bent structure defining a hollow space, in which the bodily part is comprised when supported by the same. The zipfastener 120 of the openable orthopaedic cast 1000 is placed along a cut in the longitudinal extension of the support element 1050. Hence, such a cut defines a first limiting longitudinal end 1061, at one side of the cut, and a second limiting longitudinal end 1062, at the other side of the cut, which ends are essentially facing towards each other. In the openable orthopaedic cast 1000, the surfaces of one or both of the upper side and the lower side of the first pre-adhesive sheet 111, and the surfaces of one or both of the upper side and the lower side of the second preadhesive sheet 112 are mechanically adhered to, e.g. to a surface of the support element 1050, or within, e.g. between an inner layer 1101 and an outer layer 1102 of the support element 1050. The first zip-fastener half 121 is thereby brought in an essentially constant spatial relationship relative the first limiting longitudinal end 1061. Accordingly, the second zip-fastener half 122 is set in an essentially constant spatial relationship relative the second limiting longitudinal end 1062.

Casting a bodily part of a patient with the orthopaedic cast 1000, i.e. producing the orthopaedic cast 1000, is conducted by sequential operative steps. Such casting or production may, for example, typically include the following steps: • Providing the bodily part with at least one, preferably two, protective and soft stockinette(s). At this point and as suitable, local bolstering may be conducted to provide, for example, spots with additional pressure or protection.

• Providing the bodily part with an inner layer 1101 of the support element 1050, around and on the outer surface of the stockinette(s). Such an inner layer 1101 may, for example, be a curable casting tape or similar used in general casting, which may be easily cut after curing. At this point and as suitable, additional reinforcement stripes or splints may be included to provide, for example, spots with additional rigidity.

• Providing a resealable cast opener 100 in its closed state on the outer surface of the inner layer 1101, such that the central zip-fastener 120 thereof is extending along a line suitable for resealable opening of the final orthopaedic cast 1000. Depending of the type of pre-adhesive composition 115 employed, activation as described elsewhere herein may be conducted at this stage or at subsequent stages, as readily understood by the skilled person. The outer surface of the central zip-fastener 120 may be covered by a protective layer, e.g. e plastic film or another suitable such layer with an ability to protect the zip-fastener 120 from direct contact with e.g. an outer layer 1102 of the support element 1050. Such a protective layer facilitates the steps of cutting through the outer layer 1102 along the extension of the zip-fastener 120 and the opening of the same, as described in further detail herein below. The outer layer 1102 may otherwise, depending on type, interact mechanically in an undesirable way with the zip-fastener 120 to make opening of the same more difficult.

• Providing the bodily part with an outer layer 1102 on/over the previously provided inner layer 1101 and on/over the resealable cast opener 100. The latter is thereby placed in between the inner layer 1101 and the outer layer 1102. Such an outer layer 1102 may, for example, be of the same type as the previously provided inner layer 1101. At this point and as suitable, additional reinforcement stripes or splints may be included to provide, for example, spots with additional rigidity.

• Allowing, when applicable, the inner layer 1101 and the outer layer 1102 to cure.

In addition, allowing the first pre-adhesive sheet 111 and the second preadhesive sheet 112 to develop a mechanical connection with the inner layer 1101 and/or the outer layer 1102 by carrying out, or having carried out in a previous step, a suitable activation event.

• Cutting through the outer layer 1102 along the extension of the zip-fastener 120 to expose the same. Suitable means for doing this is dependant on the type of material of the outer layer 1102 and readily understood by the skilled person. For example, a pair of scissors or a suitable oscillating cast saw may be used. • Fully open the zip-fastener 120 to transition from a closed state to the open state.

• Cutting through the thereby exposed inner layer 1101 along the extension of the zip-fastener 120. When using one stockinette, this may be simultaneously cut through. When using a plurality of stockinettes, such as two, all of these but the most inner, or also the most inner, may be simultaneously cut through.

• Setting the resealable cast opener 100 in its closed state by closing the zip-fastener 120.

By carrying out above steps, or variants thereof, an orthopaedic cast 1000 of the invention is obtained in its closed state to provide support of the enclosed bodily part. By suitable variations of individual steps as readily understood by the skilled person, e.g. by suitable local bolstering, reinforcement stripes and/or splints, the orthopaedic cast 1000 may advantageously be individually adapted to facilitate the healing and/or amelioration of a bodily part in need of medical treatment by casting. Openable and closable devices of the prior-art, e.g. such used for secondary casting, cannot as easily be individually adapted to the same degree as the present orthopaedic cast 1000.

Advantageously, the present orthopaedic cast 1000 may be fully or partly opened, i.e. set in the open or partially open state, for inspection or treatment of the encompassed bodily part, followed by closure, i.e. transition to the closed state, for renewed immobilization and support of the bodily part. Such cycling between closed states via an open state or partially open state may, for example, typically include the following steps: • Providing a bodily part with an orthopaedic cast 1000 comprising a resealable cast opener 100 set in the closed state, to achieve immobilization of the bodily part.

• Setting the resealable cast opener 100 of the orthopaedic cast 1000 in the partially open state or in the open state, to partially expose the bodily part. At this point, the orthopaedic cast 1000 may be fully removed and separated from the bodily part, typically when set in the open state.

• Inspection or treatment of the exposed part of the bodily part.

• Setting the resealable cast opener 100 of the orthopaedic cast 1000 in the closed state, after placement around the bodily part if previously fully removed, for reimmobilization of said bodily part.

According to one embodiment, the resealable cast opener 100 may be provided with one or two intermediate inner sheets 127, 128, for the provision of an intermediate force transferring zoon between the zip-fastener 120 and at least one of the first pre-adhesive sheet 111 and the second pre-adhesive sheet 112. Such intermediate inner sheets 127, 128 may be made of a suitable elastic or semi-elastic material well known in the art. Advantages of one or two such intermediate inner sheets 127, 128 include reduction of the magnitude of peak force applied on the zip-fastener 120 upon internal movement of the bodily part encompassed by the orthopaedic cast 1000. Examples of suitable elastic or semi-elastic materials include, but is not limited to, curable polyurethane based casts of the prior-art described elsewhere herein.

According to one embodiment, the pre-adhesive composition 115 may be essentially constituted by a suitable glue or adhesive. The selection of suitable glue or adhesive is dependent on the type of support element 1050 employed, as readily understood by the skilled person. A resealable cast opener 100 equipped accordingly may be further provided with suitable plastic or polymeric protective films, e.g. to protect the glue or adhesive such a pre-adhesive composition 115, prior to activation by removal of the same. Examples of suitable plastic or polymeric protective films include, but is not limited to, vinyl chloride-vinyl acetate copolymers, plastic paraffins and modified cellulose.

According to one embodiment, the pre-adhesive composition 115 may be essentially constituted by a plurality of suitable hook-shaped semi-flexible extensions. Such extensions may be adapted to mechanically interact with another corresponding set of extensions to provide a mechanical connection between two associated surfaces, e.g. between a surface of a pre-adhesive sheet 111, 112 of the resealable cast opener 100 and an outer or inner surface of the support element 1050. An example of materials, systems or products comprising such suitable hookshaped semi-flexible extensions include, but is not limited to, Velcro.

According to one embodiment, the pre-adhesive composition 115 may comprise a chemical group selected from the groups consisting of hydroxyl, amino and isocyanate. Such a chemical group may be covalently bond to one or both of the surfaces of the first pre-adhesive sheet 111 and the second pre-adhesive sheet 112. The chemical group may be bond via a direct bond or via a chemical linker moiety. Examples of such chemical linker moieties include, but is not limited to, C1-20-alkyl ene, oligomers of ethylene oxide or propylene oxide independently comprising 1 to 30 consecutive -OCH2CH2- or -0(CH)CH3CH2- units. The linker moiety may further comprise aromatic units such as benzene group, e.g. one or several diphenylmethane units. In order to provide a sufficient mechanical connection by formation of covalent bonds between one or both of the surfaces of the first pre-adhesive sheet 111 and the second preadhesive sheet 112 and the support element 1050 upon activation, an appropriate reacting group of the latter is selected as well understood by the skilled person. Suitable combinations between chemical groups which may react to form such covalent bonds include, but is not limited to, hydroxyl : isocyanate, amino : isocyanate, isocyanate : amino and/or hydroxyl.

According to one embodiment, the support element 1050 may comprise a chemical group selected from the groups consisting of hydroxyl, amino and isocyanate. Such a chemical group may be covalently bond to the surface or region of the support element 1050 which forms a mechanical connection to the resealable cast opener 100 upon or after activation. The chemical group may be bond via a direct bond or via a chemical linker moiety. Examples of such chemical linker moieties include, but is not limited to, C1-20-alkylene, oligomers of ethylene oxide or propylene oxide independently comprising 1 to 30 consecutive -OCH2CH2- or-0(CH)CH3CH2- units. The linker moiety may further comprise aromatic units such as benzene group, e.g. one or several diphenylmethane units. In order to provide a sufficient mechanical connection by formation of covalent bonds between one or both of the surfaces of the first preadhesive sheet 111 and the second pre-adhesive sheet 112 and the support element 1050 upon activation, an appropriate reacting group of the former surfaces is selected as well understood by the skilled person. Suitable combinations between chemical groups which may react to form such covalent bonds include, but is not limited to, hydroxyl : isocyanate, amino : isocyanate, isocyanate : amino and/or hydroxyl.

According to one embodiment, at least one, such as both, of the pre-adhesive composition 115 and the support element 1050 may comprise a di- or poly-functional isocyanate, e.g. 4,4'-methylenediphenyldiisocyanate. Both of the pre-adhesive composition 115 and the support element 1050 may further comprise hydroxyl and/or amino groups, such as e.g. by comprising cellulose or a chemically modified cellulose. One or both of the pre-adhesive composition 115 and the support element 1050 may optionally comprise a polyether polyol, such as e.g. a polymer of 2-propenenitrile with ethenylbenzene, methyloxirane and oxirane. Upon activation, e.g. by provision of water or humidity, by provision of heat, by provision of a tertiary amine catalyst, e.g. 2,2'-dimorpholino diethyl ether, or a combination thereof as dependent on the combination of polymerizing regents describe above and as readily understood by the skilled person, polymerization reactions will occur to form covalent bonds between the resealable cast opener 100 and the support element 1050. A sufficient mechanical connection there between is thus provided.

According to one embodiment, the activation event may be achieved by provision of an organic or inorganic compound selected from the group consisting of polyols, polyisocyanates, amines and water. For example, when both of the pre-adhesive composition 115 and the support element 1050 comprise hydroxyl and/or amino groups, activation may be achieved by provision of a suitable di- or poly-functional isocyanate, e.g. 4,4'-methylenediphenyldiisocyanate. In another example, when both of the pre-adhesive composition 115 and the support element 1050 comprise a covalently bond isocyanate, activation may be achieved by provision of water. In yet another example, when the pre-adhesive composition 115 and the support element 1050, taken together, comprise an isocyanate and a di- or polyol, activation may be achieved by provision of a tertiary amine catalyst such as e.g. 2,2'-dimorpholino diethyl ether. In the latter example, the isocyanate may be covalently bond to both of the resealable cast opener 100 and the support element 1050 and the di- or polyol may be free.

According to one embodiment, the support element 1050 may be semi-flexible by being essentially constituted by an organic polymer. The orthopaedic cast 1000 may thereby be more easily fully removed from a bodily part in its open state as compared to the case of a more rigid support element 1050.

According to one embodiment, the zip-fastener 120 may be of an open proximal end type. The orthopaedic cast 1000 may thereby be more easily fully removed from a bodily part in its open state as compared to the case of type of zip-fasteners 120 which does not allow full separation of the zip-fastener halves 121, 122.

According to one embodiment, one or both of the first pre-adhesive sheet 11 land the second pre-adhesive sheet 112 may have an irregular lateral edge. The design of such irregular lateral edges may depend on the anatomy of the bodily part encompassed by the orthopaedic cast 1000 and be adapted to provide sections thereof with varying degree of flexibility. Advantages of such irregular lateral edges include thus, for example, the ability to further optimize zones of local variability of flexibility of the orthopaedic cast 1000, leading to e.g. improved healing of the treated bodily part.

In the claims, the term “comprises/comprising” does not exclude the presence of other elements or steps. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms “a”, “an”, “first”, “second” etc do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.

Claims

1. Method for production of an orthopaedic cast (1000) for immobilization of a bodily part of a patient by functional support in secondary casting, said orthopaedic cast (1000) comprising a resealable cast opener (100) and a support element (1050), wherein: - said resealable cast opener (100) comprising a central zip-fastener (120) with a zip-fastener handle (129) for user controlled closure and opening of said zip-fastener (120), a first preadhesive sheet (111) and a second pre-adhesive sheet (112); - said central zip-fastener (120) having a first zip-fastener half (121) and a second zip-fastener half (122) being mechanically attached, essentially along its full longitudinal extensions, to one edge of said first pre-adhesive sheet (111) and to one edge of said second pre-adhesive sheet (112), respectively; - said resealable cast opener (100) exists in one state selected from the group of states consisting of an open state, in which open state said first zip-fastener half (121) and said second zipfastener half (122) are fully separated from direct mechanical contact with each other, a partially open state, in which partially open state said first zip-fastener half (121) and said second zipfastener half (122) are partially separated from direct mechanical contact with each other and simultaneously partially reside in a constant spatial relationship relative each other along the longitudinal extension of said first zip-fastener half (121) and said second zip-fastener half (122), and a closed state, in which closed state said first zip-fastener half (121) and said second zipfastener half (122) fully reside in a constant spatial relationship relative each other along the longitudinal extension of said first zip-fastener half (121) and said second zip-fastener half (122); - the surfaces of the upper side and the lower side of said first pre-adhesive sheet (111) and the surfaces of the upper side and the lower side of said second pre-adhesive sheet (112) being adapted, by being provided with a pre-adhesive composition (115), to mechanically adhere to a support element (1050) when activated by an activation event; - said activation event being a user controlled activation event comprising at least one of the group of activation events consisting of removal of protective physical matter from said preadhesive composition (115), addition of an organic or inorganic compound to said pre-adhesive composition (115), which organic or inorganic compound initiates a chain of chemical reactions leading to the formation of covalent chemical bonds between said first pre-adhesive sheet (111) or said second pre-adhesive sheet (112) and said support element (1050) when being in contact with each other, and exposure of said pre-adhesive composition (115) to electromagnetic radiation, which electromagnetic radiation initiates or increases the rate of chemical reactions leading to the formation of covalent chemical bonds between said first pre-adhesive sheet (111) or said second pre-adhesive sheet (112) and said support element (1050) when being in contact with each other; - said support element (1050) being a bent structure comprising a first limiting longitudinal end (1061) and a second limiting longitudinal end (1062), essentially facing towards each other, and said support element (1050) defining an inner space for the encompassment of said bodily part of a patient; - the surfaces of the upper side and the lower side of said first pre-adhesive sheet (111) of said resealable cast opener (100) and the surfaces of the upper side and the lower side of said second pre-adhesive sheet (112) of said resealable cast opener (100) being mechanically adhered to or within said support element (1050) to provide said first zip-fastener half (121) of said resealable cast opener (100) in an essentially constant spatial relationship relative said first limiting longitudinal end (1061) of said support element (1050), and said second zip-fastener half (122) of said resealable cast opener (100) in an essentially constant spatial relationship relative said second limiting longitudinal end (1062) of said support element (1050); and - said method comprising the steps of: - (i) providing said bodily part with an inner layer (1101) of said support element (1050); - (ii) applying said resealable cast opener (100), being in said closed state, on the outer surface of said inner layer (1101); - (iii) providing said inner layer (1101) and said resealable cast opener (100) of step (ii) with an outer layer (1102) of said support element (1050), to achieve placement of said resealable cast opener (100) between said inner layer (1101) and said outer layer (1102); - (iv) activating said pre-adhesive composition (115) by performance of said activating event, prior to step (ii) or after step (iii) or partly prior to step (ii) and partly prior to step (iii), to provide mechanical adherence between said upper side and said lower side of said first preadhesive sheet (111), said upper side and said lower side of said second pre-adhesive sheet (112) with the inner side of said outer layer (1102), the outer side of said inner layer (1101), the inner side of said outer layer (1102) and the outer side of said inner layer (1101), respectively; - (v) cutting through said outer layer (1102) along the extension of said zip-fastener (120) of said resealable cast opener (100), to expose said zip-fastener (120); - (vi) setting said resealable cast opener (100) in said partially open state or in said open state, to partially expose said inner layer (1101); - (vii) cutting through said inner layer (1101) along the extension of the open part of said zipfastener (120) of said resealable cast opener (100); and - (viii) setting said resealable cast opener (100) in said closed state.

2. Method according to claim 1, wherein said support element (1050) is semi-flexible and comprises an organic polymer.

3. Method according to claim 1, wherein said first zip-fastener half (121) or said second zipfastener half (122) are being mechanically attached to one of said first pre-adhesive sheet (111) and said second pre-adhesive sheet (112) via an intermediate inner sheet (127, 128), for the provision of an intermediate force transferring zoon between said zip-fastener (120) and at least one of said first pre-adhesive sheet (111) and said second pre-adhesive sheet (112).

4. Method according to claim 1, wherein said protective physical matter is a plastic or polymeric protective film and said pre-adhesive composition (115) is a glue or adhesive.

5. Method according to claim 1, wherein said pre-adhesive composition (115) comprises a plurality of hook-shaped semi-flexible extensions.

6. Method according to claim 1, wherein said pre-adhesive composition (115) comprises a chemical group selected from the groups consisting of hydroxyl, amino and isocyanate, said chemical group being covalently bond to the surface of one of said first pre-adhesive sheet (111) and said second pre-adhesive sheet (112) via a direct bond or via a chemical linker moiety.

7. Method according to claim 1, wherein said organic or inorganic compound is selected from the group consisting of polyols, polyisocyanates, amines and water.