The present invention provides improved hardenable orthopaedic supports and methods of making the same. One embodiment provides a support which includes a blank made of a permeable, flexible material and including a structural region impregnated with a hardenable material and a peripheral region which will remain flexible after the hardenable material is hardened. Another embodiment provides a method of manufacturing an orthopaedic support in which a permeable, flexible material is positioned adjacent a recess of a molding element; the flexible material is contacted with a hardenable material; and the hardenable material is placed under pressure in the molding element to impregnate the section of the flexible material with the hardenable material.

TECHNICAL FIELD

This invention relates to improved hardenable orthopedic supports, e.g., splints or casts.

BACKGROUND

Orthopaedic supports are used to provide structural support and/or limit movement of a portion of a patient's anatomy. Hardenable splints and casts are commonly formed by wrapping or otherwise positioning layers of a strip or “tape” of hardenable material about the afflicted area and allowing the material to harden in place. Gauze coated with calcined gypsum has been used for many years, but more modern hardenable supports are formed with other fabrics, e.g., knitted fiberglass, and employ hardenable organic resins instead of calcined gypsum. For example, U.S. Pat. No. 4,996,979, granted Mar. 5, 1991, and U.S. Pat. No. 4,683,877, granted Aug. 4, 1987 disclose water-hardenable organic resins used in this context. Other hardenable resins used in this field include epoxies and UV-curable materials.

When using such tapes in forming orthopaedic supports, multiple layers of the tape are wrapped about or positioned on the limb or other affected part of the patient's anatomy. In applying the tape to form a cast, for example, care must be taken to firmly engage the layers during the exotherm portion of the setting period to ensure unitary bonding of the entire layered cast or assembly. This step requires care and expertise to ensure that the layers are properly bonded without causing pain or discomfort to the patient, e.g., when forming a cast around a broken limb. Applying fiberglass tape to form a water-hardenable core of a splint or support requires considerable skill and practice to form splints or supports of varying thickness which may be required or which may be desirable for certain applications. Thus, for example, when a cast is to be provided for a foot and lower leg, it may be desirable to have greater thickness in the lower portion of the cast, and a lesser thickness in the vicinity of the shin or the calf of the user. Applying layers of fiberglass cloth requires considerable experience to form a varying thickness layered cast or support which will have proper inter-layer bonding and strength.

Not all hardenable orthopaedic supports are formed by winding an elongate strip of tape around the limb or other anatomical structure. For example, U.S. Pat. No. 6,186,966, granted 13 Feb. 2001 and entitled “Hardenable Orthopaedic Support With Improved Configuration”, suggests a support which, in one configuration, may be pre-shaped to be reliably placed on an anatomical structure, e.g., a palm, wrist and forearm. Certain embodiments include a pair of spaced interwoven layers formed of high-strength materials with an open matrix of filaments or threads interconnecting the layers. The support is flexible and can conform to the intended anatomical structure without forming wrinkles, which lend the product an unsightly appearance and can lead to patient discomfort. This approach also avoids the necessity to wrap plural layers of tape, contour the tape to appropriately fit the limb, and compress the layers together to avoid delamination.

Another problem encountered in this field is the fraying of the edges of material when fabric, such as fiberglass fabric, is cut. When the hardenable resin cures, the frayed edges may harden and may cause patient discomfort or abrade adjacent soft tissue. This difficulty often plagues orthopaedic supports, including pre-shaped hardenable supports. Typically, the material which carries the resin is coated in a continuous process, e.g., by spraying or dipping the material in a bath of the resin and squeezing out some of the excess resin between a pair of rollers. Many commercially available hardenable resins, e.g., urethane resins, are viscous, tacky fluids which may stick to a die or other cutting equipment, making it very difficult to cut desired shapes. As a consequence, most commercially successful hardenable orthopaedic supports to date are sold in the form of continuous tape or rectangular swatches of a predetermined size, which must then be arranged on the patient's limb.

Some hardenable orthopaedic supports employ an inner structure which carries the hardenable resin and one or more external layers. For example, one of the splint structures suggested in U.S. Pat. No. 6,186,966, noted above, includes a water-pervious outer layer and an inner layer adapted to keep the patient's skin dry. Water-hardenable orthopaedic supports are often stored and shipped in sealed, water-impervious packages, e.g., a plastic blister pack. The resin is in contact with the our layers during storage and shipment and, over time, resin can migrate through one or both of the outer layers. When this product is removed from the package, wetted (if necessary) and applied to the patient, the resin on the outside of the product can harden on the physician's or technician's hands and can harden on the patient's skin. This can also lead to an irregular, mottled surface, making the support less attractive and lending a less professional appearance.

DETAILED DESCRIPTION

Various embodiments of the present invention provide orthopaedic supports, subassemblies for such supports, methods of manufacturing orthopaedic supports, and apparatus for use in manufacturing orthopaedic supports. The following description provides specific details of certain embodiments of the invention illustrated in the drawings to provide a thorough understanding of those embodiments. It should be recognized, however, that the present invention can be reflected in additional embodiments and the invention may be practiced without some of the details in the following description. To facilitate understanding and readability, a few select shapes will be discussed, followed by a more detailed analysis of the internal structure of certain embodiments, and methods in accordance with other embodiments are then described.

In one embodiment, a hardenable orthopaedic support for providing orthopaedic care to a patient is disclosed. In this embodiment, the support comprises a layer of padding material having an outer portion, a layer of napped material, and a blank made of a flexible, permeable material. The layer of napped material may have a substantially smooth side, a napped side, and an outer edge portion, where the napped side faces the blank. The outer portions of the layers of napped material and padding material may be at least partially attached. The blank may be at least partially impregnated with a hardenable material, and the blank may be located between the layer of napped material and the layer of padding material.

In another embodiment, a method of using a hardenable orthopaedic support is disclosed. In this embodiment, the method comprises forming a blank, the blank being at least partially permeable to an activating agent and impregnating at least part of the blank with a hardenable material which will harden in response to application of the activating agent. The method may also comprise enclosing the blank between two layers of material, wherein at least one of the materials is a napped material, wherein the napped material has a napped side facing the blank. The method may also comprise connecting the two layers substantially near their edges to completely enclose the blank and form a support structure.

Exemplary Designs

FIGS. 1A–Dshow an orthopaedic support10in accordance with one embodiment for providing splinting or casting action for an extremity of a patient. The orthopaedic support10shown inFIG. 1is particularly well-adapted for use with an upper extremity, such as a patient's arm, and includes three laterally-extending lobes12a–cseparated by two narrowed joining regions14a–b. In this particular embodiment, the lobes12and joining regions14are generally symmetrical about a longitudinally-extending axis A. In the illustrated embodiment, each of the lobes12have a width (measured transversely at its widest point) at least about 1.3 times the width (measured transversely at its narrowest point) of the or each contiguous joining region14. In one embodiment, each of the lobes12has a width at least about 1.5 times the width of at least one contiguous joining region14. In the support10ofFIG. 1, the distal joining region14ahas a first width W1, the proximal joining region14bhas a second width W2, and middle lobe12bhas a third width W3. The third width W3is at least about 1.3 times both the first width W1and the second width W2and is at least about 1.5 times the first width W1.

The orthopaedic support10is designed to drape over a patient's limb and to minimize wrinkles in the final cast or splint, as wrinkles can cause pressure points and ultimately cause discomfort or injury to the patient. The support10also guides a medical professional in placing the support10on a patient, as each lobe12and joining region14corresponds to a particular part of a patient's anatomy. For example, the distal lobe12amay extend about a portion of the patient's hand distal of the thumb; the distal joining region14amay be aligned with the thumb to position the thumb and its web space between the distal and middle lobes12a–bof the support10; the middle lobe12bmay extend between the thumb and the wrist; the proximal joining region14bmay be aligned with the wrist to comfortably receive the ulnar styloid; and the proximal lobe12cmay extend proximally to at least partially encircle a length of the forearm.

In addition to facilitating positioning of the support10at the proper general location, the design shown inFIG. 1enables articulation of the support10to better conform to each patient's anatomy. More specifically, the narrower joining regions14can accommodate more lateral torsion, e.g., bending of the axis A inFIG. 1Ainto a non-linear shape to better accommodate a patient's anatomy. In this regard, the shape of the support10can be flexed and contoured to meet the needs of each patient, unlike more conventional rectangular supports. The multi-lobed design of orthopaedic support10can also be beneficial in that the lobes may be sized to ‘grab’ more of a patient, and thus keep the support more stable, without causing the patient undue discomfort.

As explained in more detail below, the orthopaedic support10may be formed of a flexible and/or stretchable material, e.g., an impregnated, hardenable double-knit material as described in relation toFIGS. 10–13, to permit the support10to readily drape over a patient's limb. This draping ability and the multiple-lobed shape of the support10can reduce the likelihood of developing wrinkles in the final, hardened cast or splint. Unless great care and expertise is used in applying conventional tape-type splints, such splints can wrinkle fairly readily, creating pressure points that may cause the patient discomfort or injury.

Once properly positioned, the orthopaedic support10may be held in place by a temporary aide such as an elastic bandage, a hook-and-loop tape (e.g., VELCRO® tape), gauze, a bias stockinette, or any other suitable means. The natural draping effect of the support10can also help stabilize the support while wrapping the elastic bandage or applying any other temporary aide. The orthopaedic support10can be used alone or, as discussed below, may be used as a subassembly of a more complex support (e.g., support15ofFIG. 12, which employs the device ofFIG. 1as a blank10within an envelope50having beneficial properties for some applications).

FIGS. 2–9show several different orthopaedic supports in accordance with alternative embodiments. The orthopaedic supports100–170depicted inFIGS. 2–9may be formed of similar materials and in similar methods to those outlined below, and may function similarly to the orthopaedic support10shown inFIG. 1and described above. These alternative supports100–170, however, are shaped differently from the support10ofFIG. 1.

The orthopaedic support100ofFIG. 2has a pair of lobes102a–bseparated by a single narrow joining region104. Such a 2-lobed design may be used to support an arm, but it may be more appropriate for other anatomical structures, e.g., a leg. Both of the lobes102a–bhave a width which is at least about 1.5 times the width of the joining region104; in the particular illustrated shape, the distal lobe102ahas a width at least about 1.75 times the width of the joining region104and the proximal lobe102bhas a width at least about 2.5 times the width of the joining region104.

The orthopaedic support110ofFIG. 3has a pair of lobes112a–b, a distal narrow length114awhich extends distally of the distal lobe112a, and a narrow joining region114bbetween the distal lobe112aand the proximal lobe112b. The orthopaedic support120ofFIG. 4has an elongate joining region124between a distal lobe122aand a proximal lobe122b. The joining region124in this embodiment has a proximal length124bof substantially constant width and a narrowed neck124aconnecting the proximal length124bto the distal lobe122a.FIG. 5illustrates an orthopaedic support130having a distal lobe132aand a proximal lobe132bseparated by a narrow joining region134aand a proximal length134bwhich extends proximally from, and is narrower than, the proximal lobe132b. InFIG. 6, orthopaedic support140includes a distal lobe142aand an elongate proximal lobe142b, which may be generally rectangular in shape or may taper outwardly in a proximal direction. A narrow joining region144may connect the two lobes142.

Unlike the multi-lobed designs ofFIGS. 1–6, the orthopaedic support150ofFIG. 7has a single wide proximal region152, which may flare out proximally, and a generally rectangular distal region154, which is narrower than the proximal region152. Although this shape does have utility, it is not considered to be as beneficial as some of the previously-described embodiments, e.g., the support10ofFIG. 1.FIG. 8illustrates a design which has a distal length162with a laterally-extending tongue163, a distal joining region164a, a distal flared region166a, a proximal joining region164b, and a proximal flared region166b. The orthopaedic support170ofFIG. 9has a distal length172with a laterally extending tongue173, a narrow joining region174, and an elongate proximal region. The asymmetrical designs ofFIGS. 8 and 9can be advantageous in some applications, but may not be as widely useful as the symmetrical design shown inFIG. 1, for example.

Exemplary Structures

Referring back toFIG. 1, the orthopedic support10may include a centrally-disposed structural region20and a peripheral region22extending outwardly beyond the structural region. In the illustrated embodiment, the peripheral region22extends about the entire periphery of the structural region20and has a substantially constant width about the entire periphery. As a consequence, the structural region20has the same general multi-lobed, nonrectangular shape as the entire support10. In other embodiments, the peripheral region22extends around only a portion of the circumference of the structural region20, with the structural region20extending to the edge of the support10along the remainder of its circumference. The width of the peripheral region22may be varied as desired. It is anticipated that a peripheral region22having a width of about ⅛ inch to about ½ inch, e.g., about ⅛ inch to about ¼ inch, will suffice for most applications.

Some or all of the support10may be impregnated with a hardenable material. The hardenable material is adapted to harden in response to a specific activating agent. For example, a water-hardenable material, such as a prepolymerized urethane material, may be employed. When the water-hardenable material contacts water, it will harden. Water-hardenable materials are well known, and have been used heretofore in orthopaedic devices. See, for example, U.S. Pat. Nos. 4,996,979 and 4,683,877, both of which are incorporated herein in their entirety. As is known in the field, other hardenable materials may instead be used, such as UV-curable resins or one component of a two-component epoxy.

In one embodiment, the structural region20of the support10is impregnated with the hardenable material, but the peripheral region may remain free of the hardenable material. As a consequence, when the support10is in place and the water or other agent is used to activate the hardenable material, the structural region will harden to support the limb or other anatomy to which it is applied. Because the peripheral region22is free of the hardenable material, the peripheral region will not harden when contacted with water. As a consequence, the peripheral region may flex with the patient's movements, both increasing patient comfort and avoiding abrasion or other damage which can occur with the stiff projecting edges of conventional casting tapes or the like.

A variety of cross-sectional structures may be suitable for the orthopaedic support10ofFIG. 1.FIG. 10is a schematic cross-sectional view of the orthopaedic support10in one such embodiment taken along line10—10ofFIG. 1. As shown inFIG. 10, the support10may comprise a double-knit fabric32including surface knits34and36and spacer yarns38. The surface knits34and36can be of the same or different knit patterns. These patterns can range anywhere from smooth, essentially continuous surfaces to meshes and other more complex knits. They may be knit from materials such as polyester, nylon, and various high strength fibers, including fiberglass, aramid and/or carbon fibers. The spacer yarns38keep the surface knits34and36a specific distance apart, and allow for individual surface movement. The spacer yarns38may comprise monofilament yarns, but can also be multi-filament yarns. The spacer yarns38may be made from polyester, nylon, or other thermoplastic materials that can be drawn into a yarn of the desired diameter; they may also be made from glass or aramid fibers. The thickness of the double-knit-type material may range from about 1/16-inch thickness to about ¾-inch thickness, with about ⅛-inch to about ⅜-inch being preferred. In another embodiment (not shown), a permeable foam material may be used instead of the spacer yarns, with the surface knits34and36being formed as separate knit layers and subsequently bonded to opposite faces of the foam, e.g., with an adhesive.

In one embodiment, the double-knit type material includes a substantial proportion of high strength materials such as fiberglass, aramid fibers such as KEVLAR, or carbon fibers. It is noted that fiberglass, KEVLAR, and carbon fibers may all have tensile strengths which are an order of magnitude or more greater than the tensile strength of many thermoplastics, e.g., LDPE. More generally, high-strength fibers used in certain embodiments have tensile strengths greater than 500 MPa, e.g., 1,000 Mpa or greater. They also may be fairly stiff. To better accommodate this stiffness, the double-knit type fabric may be of a fairly loose weave.

In one suitable double-knit fabric, the upper layer34and the lower layer36are formed of fiberglass and the open matrix of interconnecting fibers38is formed of 30 denier polyester monofilament, a thermoplastic material. The fiberglass constitutes about 71% by weight (wt. %) of the assembly, and the polyester comprises the remaining 29 wt. %. Using this type of assembly, with a relatively stiff, high-strength material and a thermoplastic material, the double-knit type fabric may be concurrently cut and heated to melt and fuse the thermoplastic into the fiberglass, thereby limiting fraying or unraveling of the cut edges. Ultrasonic cutting and sealing equipment to accomplish the foregoing is available, for example, from Branson Ultrasonics Corp., 41 Eagle Road, Danbury, Conn. 06813-1961. More generally, the amount of the fiberglass or other stiffer, high-strength filaments may range from 10 wt. % to 100 wt. % of the double-knit fabric, e.g., about 20 wt. % to 80 wt. %, with the remainder comprising any desired filaments to suit the application, with a thermoplastic better enabling the cut edge treatment described above.

FIG. 11schematically illustrates a modified embodiment of a support10athat reinforces the double-knit fabric with glass knits or other high strength fabrics to increase their strength. In this particular embodiment, fiberglass fabric40and42may be bonded to the surface knits34and36by adhesive webs44and46, respectively. This bonding could also be achieved by any other known technique such as by flame bonding, or by sewing, for specific examples. The lamination of the glass knit fabrics40and42to the double-knit material by the adhesive layers44and46also reduces fraying of the glass knit when the assembly is cut, and can help hold the entire assembly intact during subsequent operations.

If so desired, the support10shown inFIG. 1may be employed as a casting blank which is retained in an outer envelope.FIG. 12illustrates an orthopaedic support15in accordance with one such embodiment. The support15includes a blank, illustrated as the support10ofFIGS. 1 and 10, positioned in a flexible envelope50. If so desired, the blank may have any other suitable structure. For example, the blank or central body material may comprise a reinforced double-knit material10aas described in relation toFIG. 11, multiple layers of double-knit material, multiple layers of double-knit material separated by a foam laminate or other divider, foam material with a single-knit material attached to both sides (such as cast tape), a layer of foam without any fabric attached thereto, multiple layers of single-knit material. Instead of knit materials, woven materials, felted materials, or other nonwoven materials may be employed. In one particular embodiment, the blank10ofFIG. 12comprises a layer of a flexible, water-permeable foam material with at least a central support region of the foam being impregnated with a water-hardenable material.

The orthopaedic support15ofFIG. 12includes an exterior layer60and a interior layer52that together form an envelope50which may substantially encapsulate the blank10. The exterior layer60is designed to be on the outside of the orthopaedic support15when applied, while the interior layer52is designed to be adjacent the patient's skin (and possibly separated by a fabric, bandage or other item). In one embodiment, the exterior layer60is made of a material having a relatively smooth external surface62and a lofty, internal nap64. In certain embodiments, the exterior layer60comprises the loop-type material or hook material of a mating hook and loop-type fastening system, such as VELCRO®. In one suitable embodiment the exterior layer comprises an unbroken loop material (“UBL”), which may correspond to the “soft,” “fuzzy” loop-type material of a mating hook and loop-type fastener. In one particular embodiment, the UBL comprises a flexible knit fabric which has one napped surface. The exterior layer60may be placed with the napped side64facing the blank10and the smoother backing62facing outwards. The exterior layer60may also be formed of any other napped material, e.g., a knitted material such as terrycloth. In this embodiment, the napped side of the material would be placed facing the blank10. In another alternative embodiment, any suitably flexible and/or stretchable material with a high loft may be used, typically with a high loft side facing the blank10. Napped materials, including unbroken loop materials, are available from sources such as Gehring Textiles Inc. of New York, N.Y.

The interior layer52may be made of foam padding, e.g., an open-cell polyurethane. Foam padding may provide comfort for the patient, as the interior layer52will likely be the layer touching the patient's anatomy. One skilled in the art will recognize that the interior layer52may be made of a wide variety of materials, such as fabric, UBL materials, napped materials, other padding, etc.

The exterior layer60and interior layer52may be bonded together at their outer edges54,66by thermal welding, by permanent adhesive, by ultrasonic welding, stitching, or in any other desired manner. The bonding may be accomplished in successive spots or lines or may be continuous. The impregnated blank10is therefore contained within the envelope50between the exterior layer60and interior layer52, which will inhibit migration or leaking of the resin during shipment and storage. In one embodiment, the blank10is placed between the exterior layer60and interior layer52immediately after being impregnated. Once the exterior layer60and interior layer52are bonded together, the orthopaedic support15may be sealed in a water vapor-impermeable package (not shown). Sealing the orthopaedic support15in the package quickly can reduce exposure to moisture contained in the air. If a UV-curable resin or the like is instead used to harden the support10once in place, the package need not be water vapor-impermeable, but it should be opaque to ultraviolet radiation.

The water vapor-impermeable package may be formed of metallized mylar, aluminum foil, or any known water vapor-impermeable material which will reduce the chances of premature activation and hardening of the urethane or other water-hardenable material which is impregnated into the blank10. One suitable water vapor-impermeable sheet material comprises aluminum foil coated with plastic on both sides, available from Richmond Tech, Inc., 1897 Colton Avenue, Redlands, Calif. 92374-9797. This material has a low moisture vapor transfer rate of about 0.0006 grams per 100 square inches per day.

In one embodiment, the blank material is initially impregnated with the water-hardenable material, and then the entire soft good product, tape or blank, is packaged in a water vapor impermeable package. When it is time to apply the product to a patient, the package is opened, the product is immersed in water or water is applied to it, and the product is mounted onto the part of the anatomy requiring support or splinting. With the open-work matrix of the double-knit material, for example, rapid and thorough penetration of the water and activation of the urethane occurs. In the case of soft goods types of products, straps may be employed to mount the support firmly on the injured portion of the anatomy, water is applied or injected, and the water-hardenable material conforms to the configuration of the patient. In another embodiment, blanks may be immersed in water and promptly applied to the injured portion of the anatomy before the hardening occurs.

The use of a napped material prevents or slows down resin (or other hardenable material) migration over time. This effect appears to be stronger when the napped side of a napped material such as UBL is located adjacent a resin-impregnated material. As noted above, resin has a tendency to leak or migrate out of an orthopaedic support over time, such as during shipping or storage. When the orthopaedic support is ultimately activated, the resin that has leaked out may cause imperfections or protuberances on the outer surface of an orthopaedic support. It has been found that UBL is useful in preventing or retarding resin migration, even during long shipping or storage periods. By using a napped material such as UBL as an exterior layer60, the orthopaedic support15ofFIG. 12also provides a smoother and cleaner outer surface on the finished support because of the smooth surface of the backing62of the napped material and the reduced migration of hardenable material therethrough.

The UBL material used in selected embodiments provides a smooth external surface with minimal wrinkles. The relatively smooth surface is inherent with many UBL materials, and the ability of UBL materials to stretch and flex reduces the number of unsightly wrinkles on the orthopaedic support15. In addition, UBL materials are generally quick-drying, so that when the orthopaedic support15is, for example, immersed in water to activate the resin, the UBL material60(and thus the outside of the support15) dries quickly. UBL materials are also relatively light and strong when compared to alternative materials, and are also more resistant to damage, such as scratches or tears. This is particularly true when compared to foam padding. UBL materials may also be lower profile than foam padding, which tends to be somewhat bulky.

In one embodiment, UBL or napped materials with a larger amount of loft may be used. Loft is the thickness of the “fuzzy” or napped part of the unbroken loop material. It is believed that a thicker loft may result in additional resistance to flow or migration of resin. This may be related to the fact that loft creates a layer of air between the fabric and the blank10; it is believed that this layer of air limits contact between the resin and the outer body of the napped fabric, limiting migration of resin or other hardenable material through the thickness of the fabric to the exterior surface.

As described above, the interior layer52may be made of foam padding or other padding in one embodiment. Foam padding, like UBL material, provides resistance to flow or migration of resin; closed-cell foams may be better in this regard than open-cell foams. Foam padding, however, is not optimal for use on the exterior layer60, as it is easily scratched or damaged. Foam padding does provide a satisfactory level of cushioning for the patient, making the orthopaedic support15more comfortable. In one embodiment, the foam padding is between one-eighth (⅛″) of an inch and five-eighths of an inch (⅝″) thick. One skilled in the art will recognize that many alternatives for both the interior layer52and exterior layer60exist, such as using a UBL material for an interior layer52, using foam padding as an exterior layer60, having both layers made of the same material, using fabrics, plastic sheeting, or other materials for either layer. Suitable foams are commercially available from a number of sources, including Foamex International of Linwood, Pa.

In one embodiment, the orthopaedic support15(and thus the interior layer52, exterior layer60, and blank10) has substantially the same shape as the blank10described in relation toFIG. 1. In this embodiment, the interior layer52and exterior layer60may be slightly larger than the blank10so the layers can be sealed together at their edges54and66to create the envelope50of the orthopaedic support15. One skilled in the art will recognize that other shapes, such as those described in relation toFIGS. 2–9, are also suitable and within the scope of the invention. In another embodiment, the envelope50of the support15has a shape which is different from the shape of the blank10.

FIG. 13is an exploded perspective view of the orthopaedic support15ofFIG. 12. InFIG. 13, the interior layer52and the exterior layer60form the outer envelope (50inFIG. 12) of the orthopaedic support15. The slightly smaller blank10fits within the inner and outer layers52,60. If so desired, a reinforcement70may be included to provide additional stiffness and/or strength to the orthopaedic support15. The reinforcement70may be attached to the blank10(such as by an adhesive, etc.) or may otherwise be located within or on the external surface of the envelope50of the orthopaedic support15. In this embodiment, a reinforcement70impregnated with a hardenable material is used. This reinforcement70provides additional stiffness when the orthopaedic support15is hardened for use. The reinforcement70can also provide additional high strength fibers, such as fiberglass, to the orthopaedic support15, which also adds strength and stiffness to the support15. In one embodiment, the reinforcement70may comprise one or more layers of single knit glass and have a rectangular shape, though other shapes may instead be employed. In another embodiment, the reinforcement70may comprise an impregnated casting tape having a central area of double-knit type fabric, an exterior layer, an interior layer, and an intermediate open-work matrix of yarns or fibers integrally knit or woven into the fabric and extending between the two layers, where at the edges of the tape the two layers are merged into a single thickness of fabric. One skilled in the art will recognize that many other materials, shapes, and designs may be used for a reinforcement70and all are within the scope of the invention.

In one embodiment, the reinforcement70extends longitudinally along at least a portion of the structural region (20inFIGS. 1 and 12, for example), but does not extend into the peripheral region22. If two or more narrowed joining regions (14inFIG. 1, for example) are used, the reinforcement may extend longitudinally through all of the joining regions. Looking atFIG. 1A, the reinforcement70(not shown inFIG. 1A) may extend proximally along the axis A from a distal end in the distal lobe12ato a proximal end in the proximal lobe12c. For example, a rectangular three-inch (3″) wide strip of impregnated tape could be used, as well as other shapes and sizes. This additional reinforcement70enables the use or narrower joining regions14without unduly sacrificing strength and stiffness of the finished article.

In the illustrated embodiment, the reinforcement70is an elongate rectangle. Other suitable shapes may instead be employed. If so desired, the reinforcement70has a non-rectangular shape. In one embodiment (not shown), the reinforcement70has a multiple-lobed design generally corresponding to the arrangement of the blank, with a wider lobe being positioned in one or more of the lobes12of the blank and a narrower section being received in one or more of the joining regions14. It is anticipated that the reinforcement70in such an embodiment will be smaller than the blank, though, with the periphery being spaced a fixed or variable distance from the peripheral region22of the blank10.

The reinforcement70may be held in place with an adhesive or other attachment, or may also be held in place by the covering materials (e.g., the exterior layer60). In one embodiment, the reinforcement70will bond with the blank10as the hardenable material hardens and the two items laminate together, which will also help prevent relative movement between the reinforcement70and the blank10, further strengthening the hardened support.

Exemplary Methods of Manufacture

Orthopaedic supports in accordance with embodiments of the invention may be manufactured in a variety of ways. For ease of understanding, reference is made in the following discussion to the specific support or blank10and support15shown in FIGS.1and10–13. It should be recognized, however, that aspects of the present invention can be used to manufacture blanks or supports having other shapes and structures, as well.

In one embodiment, a suitable hardenable material is applied to the material from which the support or blank10is formed and this material is then cut to the desired non-rectangular shape. If so desired, this cut blank10may be used as a support without any additional layers. Alternatively, the blank10can be received within an envelope50and this assembly can be used as a support15.

As noted above, though, many of the hardenable materials used in orthopaedic applications are tacky, viscous materials which are not conducive to cutting one blank10after another in a commercial production environment. Cutting the desired shapes from continuously coated material essentially necessitates that the entire blank10carry the hardenable material and producing a peripheral region which is free from the hardenable material, if such a peripheral region is desired, would be problematic.

In a method in accordance with another embodiment of the invention, the hardenable material is urged under pressure in a molding element to impregnate at least a portion of the flexible material from which the support or blank is formed. This permits relatively complex shapes to be formed from fabric which has not yet been treated with the hardenable material. These shapes may be subsequently impregnated with the hardenable material using the molding element. Alternatively, an excess of the flexible material used to form the support10may be placed in the molding element. Only the shape corresponding to a mold shape of the molding element will be impregnated with the hardenable material. Thereafter, excess fabric can be trimmed, leaving an impregnated blank10of the desired shape. In this application, the entire blank10may be impregnated with the hardenable material.

In an alternative embodiment, a blank10is produced with a structural region20impregnated with hardenable material and a peripheral region22which is free from the hardenable material.FIG. 14illustrates a molding element200which is well-suited for manufacturing such blanks10on a commercial scale. The molding element200includes a first molding member210and a second molding member250. The illustrated first molding member210contains two identical recesses212a–bwhich are offset1800in orientation from one another. Similarly, the illustrated second molding member250includes two identical projections252a–bwhich are offset 180° in orientation from one another. The projections252aand252bof the second molding member250are adapted to be received in a complementary one of the recesses212aand212b, respectively, in the first molding member210. This enables two supports10to be produced in a single operation of the molding element200. The molding element200is not limited to a particular number of pairs of recesses212and projections252, however; molding elements having one or more recess/projection pairs are equally within the scope to the invention. In one embodiment, both of the molding elements210and250are made out of aluminum, although other materials, e.g., stainless steel or other metals or suitable plastic materials such as HDPE, can be used.

The first molding member210has a first confronting face214in which the recesses212are formed and the second molding member250has a second confronting face254from which the projections252extend. The recesses212are adapted to receive a hardenable material, e.g., a water-hardenable or UV-curable resin, therein. Peripheral steps220aand220bextend about the peripheries of the recesses212aand212b, respectively. These peripheral steps220may extend about the entire periphery of the associated recess212. Alternatively, the peripheral steps may extend about less than the entire recess periphery. Similarly, projection252aof the second molding member has a peripheral step260awhich extends about at least a portion of the projection periphery and projection252bhas a has a peripheral step260awhich extends about at least a portion of the projection periphery.

FIG. 15schematically illustrates the two molding members210and250juxtaposed for use. Only one recess212aand complementary projection252ais shown; the other recess212band projection252bmay have substantially the same shape and are omitted for ease of illustration. As shown inFIG. 15, the peripheral step220of the first molding member210is recessed from the confronting surface214and surrounds the perimeter of the recess212and is used to support the peripheral region22of a blank10. The peripheral step220helps to contain resin or other hardenable material in the recess212during manufacture, as described below. The outer edge of the step220is connected to the confronting surface214by a substantially perpendicular sidewall224. The sidewall224approximates the perimeter of the intended blank10. The confronting face214may be generally planar and define one plane and the step220may be recessed from the confronting face214so the step220is in a second plane parallel and spaced apart from the first plane. The recess212is recessed from the step220so as to be in a third plane spaced apart from the first and second planes. The outer surface214, step220and recess212are in respective planes that may be substantially parallel to each other and be connected by portions of the first molding member210substantially perpendicular to those planes.

The projection252projects away from the confronting face254of the second molding member250. The peripheral step260of the second molding member250is spaced apart from the confronting face254and is juxtaposed with the step220on the first molding member210in manufacturing the blank10. A forcing surface of the projection252is spaced apart from the step260and is even further separated from the confronting face254than is the step260. The confronting face254, peripheral step260, and forcing surface of the projection252may be in three different planes substantially parallel to each other and be connected by portions of the second molding member250substantially perpendicular to those planes. The surfaces252,254, and260of the second molding member250correspond in size and pitch to the surfaces212,214and220, respectively, of the first molding member210. These surfaces may be substantially level when in use. In an alternative embodiment, the second molding member250need not comprise a single contiguous body with a continuous confronting face254adapted to closely juxtapose with the confronting face214of the first molding member210. For example, the second molding member250may comprise two separate bodies, each of which has the size and shape of one of the projections252of the illustrated embodiment. Such an independent member250may be used in a manner analogous to a punch in a punch and die operation.

In use, a flexible material to be impregnated may be positioned with respect to one or both of the recesses212and/or one or both of the projections252. If so desired, the flexible material may already be cut to conform to the shape of the sidewall224of a single one of the recesses212. Alternatively, the flexible material may extend outwardly beyond the sidewall224, e.g., it may take the form of a large rectangle large enough to completely cover one or both of the recesses212. When the confronting faces214and254of the first and second molding members210and250, respectively, are juxtaposed, the recessed step220of each recess212will confront the raised step260of the corresponding projection252. A portion of the oversized sheet of flexible material is received between these steps220and260. This portion of the material may be treated with a flexible adhesive material, such as a flexible synthetic cement, as set forth in copending U.S. application Ser. No. 09/823,968, entitled “Cast Blank Edge Treatment,” the entirety of which is incorporated herein by reference. Treating this portion of the fabric with a flexible adhesive or the like can provide a guide for trimming excess fabric from the edges of the blank10and will help keep the cut edges from fraying or shedding fibers. Because a flexible adhesive is used, this will not compromise the goal of maintaining a flexible peripheral region22of the blank10.

Before or after the flexible fabric is positioned with respect to the molding members210and250, a quantity of hardenable material, e.g., a waterhardenable resin, can be dispensed into each recess212of the first molding member. The quantity of resin placed in the reservoir may be precisely measured to deliver just the amount of resin necessary to suitably impregnate the structural region20. Depending on the nature of the resin, it may be advantageous to heat the resin to reduce its viscosity, e.g., by heating one or both of the molding members210and250.FIG. 15schematically illustrates a heat source for each of the molding members210and250as electrical resistance heaters225and265, respectively, but any suitable heat source may be employed. To impregnate the resin into the spacer, the projections252of the second molding member250are brought into alignment with the corresponding recesses212of the first molding member210and the first and second molding members210and250are urged toward one another. This squeezes the resin between a projection252and the corresponding recess212, impregnating the resin into the fabric. The resin need not be placed under pressure by squeezing the two molding members together. In another embodiment (not shown), a flexible membrane may extend over the top of the peripheral step220and the recess212of the first molding member210and be sealed against the confronting face214. By drawing a vacuum on the recess212, the membrane will be drawn toward the bottom of the recess, placing the resin under sufficient pressure to allow it to impregnate the fabric.

In the illustrated molding element200, the peripheral region22of the fabric is received between the peripheral steps220and260and may be squeezed therebetween when the molding members210and250are urged toward one another. This will limit the ingress of resin from the recess212into the peripheral region22. If a flexible adhesive or the like is applied to the peripheral region22, as noted above, forcing the molding members210and250toward one another will also squeeze the flexible adhesive to drive it into the peripheral region of the fabric. In an alternative embodiment, the adhesive may be applied to the peripheral region22and allowed to cure before the and the fabric may be trimmed to the desired blank size before the fabric is placed in the molding element200. The presence of the flexible adhesive may further restrict movement of hardenable resin from the recess212into the peripheral region22of the blank10.

By way of example, in manufacturing an orthopedic support10for a patient's upper extremity, approximately 43 grams of resin, plus or minus 1 gram, may be used for each edge-treated and cut support10. The amount of resin may vary depending on the dimensions of the orthopaedic support10, though. The molding members210and250and the resin are preferably heated to between 140 to 160 degrees Fahrenheit, but other temperature ranges are also within the scope of the invention. The flexible fabric is placed into the recess212of the first molding member210and the structural region of the fabric is held adjacent to, or in contact with, the resin. The molding members210and250may be forced together by a machine applying a force of approximately 70 pounds per square inch (“psi”) for between 30 and 60 seconds. Other ranges of pressure and time are within the scope of the invention. This forces a large percentage of the resin into the structural region20of the fabric, which ultimately will provide it with its stiffness when it is hardened.

After the allotted time has passed, the molding members210and250may be separated and the resin-impregnated blank10can be removed from the molding element200, for example by a gloved hand. If the blank10is to be used as a support, it may be packaged in water-impermeable packaging. If the blank10is to be used in manufacturing a more complex structure such as that of the support15ofFIG. 12, the blank10may be positioned between an inner layer52and an exterior layer60and those two layers52and60may be bonded to one another to create the envelope50within which the blank10is received.

It is to be understood that the foregoing detailed description and the accompanying drawings relate to some of the potential embodiments of the invention. Further modifications and variations of the present invention are contemplated. For example, with regard to materials which may be used, one or both of the outer layers of the double-knit-type material may be of high strength material, such as fiberglass, aramids such as kevlar, or other high strength fibers or materials. The spacer yarns, and one of the two outer layers may be formed of polypropylene, polyester, nylon, or a high-strength material, e.g., fiberglass or aramids such as kevlar. Other materials and yarns may also be used.

It is further noted that the properties of the double-knit-type knit-type casting material may be changed as desired by (1) altering filament size of the surface yarns or spacer yarns, (2) changing the type of surface knits, (3) changing the density of spacer yarns, (4) interweaving stretchable yarns such as lycra to increase conformability and recovery, and (5) selectively inlaying high strength fibers such as carbon, kevlar or the like. It is also noted that flat or contoured casting blanks may be knit in a completed form so that the steps of cutting the material and securing against fraying may be avoided. In addition, hardenable material other than water-hardenable material may be employed in combination with an appropriate activating agent, e.g., ultraviolet radiation for UV-curable materials or a second component of an epoxy or other known two-part polymer hardening systems. Concerning the thickness of the double-knit type material, it may range from 1/32 of an inch up to ½-inch or even one inch in thickness depending on the conformability and strength which is required or desired.

Moreover, all of the disclosed embodiments may be of variable thickness to provide selected areas of increased strength or of increased conformity to bodily configurations. It is also noted that all of the embodiments of the invention may be provided with the moisture impermeable packaging to avoid hardening of the supports or splints prior to use, while in storage, on sale, or the like.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in a sense of “including, but not limited to.” Words using the singular or plural number also include the plural or singular number respectively. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Use of the term “or,” as used in this application with respect to a list of two or more items, shall be interpreted to cover any, all, or any combination of items in the list.

Incorporated in their entirety by reference are the following U.S. applications, which are assigned to the assignee of this application: U.S. Patent Application Publication No. US 2002/0177797A1, Ser. No. 10/136,458, titled “Hardenable Orthopaedic Supports,”; and U.S. Pat. No. 6,824,522 (Henderson et al.) titled “Hardenable Orthopaedic Supports,” all filed concurrently herewith on Apr. 29, 2002. Aspects of the invention can be modified, if necessary, to employ the systems, functions and concepts of the various patents and applications described above to provide yet further embodiments of the invention.

The above detailed descriptions of embodiments of the invention are not intended to be exhaustive or to limit the invention to the precise form disclosed above. While specific embodiments of, and examples for, the invention are described above for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. For example, while steps are presented in a given order, alternative embodiments may perform routines having steps in a different order. The teachings of the invention provided herein can be applied to other devices and/or systems, not necessarily the system described herein. These and other changes can be made to the invention in light of the detailed description. The elements and acts of the various embodiments described above can be combined to provide further embodiments.

These and other changes can be made to the invention in light of the above detailed description. In general, the terms used in the following claims, should not be construed to limit the invention to the specific embodiments disclosed in the specification, unless the above detailed description explicitly defines such terms. Accordingly, the actual scope of the invention encompasses the disclosed embodiments and all equivalent ways of practicing or implementing the invention under the claims.

While certain aspects of the invention are presented below in certain claim forms, the inventors contemplate the various aspects of the invention in any number of claim forms. Accordingly, the inventors reserve the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the invention.