Patent Description:
Non-ambulatory patients suffering with minor illness or simple leg bone injuries, or the like, do not normally require the use of special purpose wheelchair cushions. However, in those long term care (LTC) cases where the patient suffers from serious postural injury or physical conditions involving pelvic or spinal related abnormalities expressing pelvic obliquity issues, anterior pelvic tilt issues, posterior and/or pelvic tilt issues, or pelvic rotation issues, the use of specially configured cushioning or other body positioning, orienting or supporting means may be required. The present disclosure is intended to address this need and to provide an adjustable wheelchair cushion that can be specified, prescribed and/or used by LTC therapists to improve the efficacy of wheelchair cushioning used in this environment.

The following is included to provide background information relating to some of the postural abnormalities toward which the present disclosure is directed, and how an LTC therapist has sought to provide, or has in fact provided, patient relief during use of a standard wheelchair and cushioning means.

ASIS & PSIS at equal height: no pelvic tilt.

L ASIS & R ASIS at equal height: no obliquity. L ASIS & R ASIS at equal depth: no rotation.

Spine balanced and upright, no rotation, no lateral curvature.

Normal lordosis in cervical and lumbar spine and normal kyphosis in thoracic spine creating the desired "S" shape. The head is functionally upright with only mild forward/lateral flexion or rotation.

In patients with this abnormality, the pelvis sits with the L or R ASIS higher than the other, causing the raising up of one hip. When one side of the pelvis is raised higher than the other, the thoracic spine curves away from the higher side creating a scoliosis over time. The neck will go into lateral flexion as if the person is dropping the ear to his or her shoulder. The lateral flexion will usually be towards the side where the hip is higher. Pressure redistribution is the therapist's support goal whether the deformity is FIXED or FLEXIBLE.

If FLEXIBLE: level the pelvis by building up the lower side.

If FIXED: accommodate for the deformity. Protect the bony prominences from pressure by "filling in" the higher side and immersing the lower side IT.

In patients with this abnormality, the pelvis sits with ASIS higher than the PSIS resulting in the posterior pelvic tilt which produces the sacral sitting posture. With excessive thoracic lordosis of the lumbar and cervical spine the patient hyperextends his or her back over the sling back of the chair, placing him or her at risk to tip the chair backwards.

Excessive lordosis of cervical spine causes hyperextension of the neck and upward eye gaze. With this abnormality, the goal is normally to utilize a cushion and back support that maximizes contact with the seat surface for optimal pelvic and spinal stability and pressure redistribution. Stability is the goal, so a back support is normally used that is tall enough for the patient.

Measurements are made from seat surface to the top of shoulder. A moldable back support to conform to the curvature of the spine is normally used.

With this abnormality, the pelvis sits with ASIS higher than the PSIS resulting in the posterior pelvic tilt which produces the sacral sitting posture. Excessive thoracic kyphosis, producing "C" shape spine, "flattening out" of the lordosis of the cervical spine and "flattening out" of the lordosis of the lumbar spine.

Decreased lordosis in cervical spine, causing forward neck flexion & downward eye gaze to floor/lap. A cushion with medial and lateral contour is often used to promote LE alignment and pelvic stability. Appropriate cushion depth should be used to prevent the patient from sliding forward as he seeks reduced pressure behind the knees. A rigid insert is often used to prevent hammocking of the seat and cushion and to keep the pelvis from collapsing into a posterior pelvic tilt.

If FLEXIBLE: A cushion with tapered adductors can be used to load the trochanters, stabilizing the pelvis in the resident's most neutral alignment.

If FLEXIBLE: A cushion with an anti-thrust component can be used to reduce forward sliding of the pelvis into posterior pelvic tilt.

If FIXED: An immersion style cushion that contours to the shape of the patient can be used to promote maximum pressure redistribution, minimizing peak pressures.

If FIXED: Opening seat-to-back angle in conjunction with a fixed tilt in the wheelchair, is often used to match the patient's ROM limitations and minimize forward sliding.

Prior art approaches have been developed to provide support cushions for use in a wheelchair apparatus which comprise a pocket in which at least one pad can be inserted into the pocket and serves to protect the user's ischial bone. One such prior art approach is disclosed in the <CIT>. This approach has shown to provide benefits regarding an increased comfort and reduced unwanted skeletal movement for wheelchair users having postural abnormalities, but lacks for instance a sufficient stabilization and pressure reduction of the pelvic and spinal structure in natural sitting positions.

An object of the present invention is to further improve upon the prior art to provide an anatomical support and seat cushion apparatus that can be easily adapted to accommodate the particular anatomical support needs of a user/patient having postural abnormalities.

The object of the invention is solved by an adjustable anatomical support and seat cushion apparatus according to independent claim <NUM>. The dependent claims relate to preferred embodiments thereof.

Briefly stated, the present disclosure is directed to an adjustable, anatomical support and wheelchair seat cushion apparatus including a base member formed of at least one layer of a thermoplastic honeycomb material, a resilient cushion member formed of upper, intermediate and lower layers of thermoplastic honeycomb material which are bonded together, the base member having an edge thereof pivotally attached to a corresponding edge of the cushion member at a hinge, and at least one pad removably insertable into a first pocket in the lower layer. The base member is pivotally attached to the cushion member. The cushion member is rotatable between a non-parallel disposition and a parallel disposition relative to the base member. An open end of the first pocket faces the base member when the cushion member is in the parallel disposition. The cushion member is characterized in that the upper layer is softer than the intermediate layer, and the intermediate layer is softer than the lower layer, a first pocket is formed in the lower layer and has an open end facing the base member when the cushion member is in the parallel disposition relative to the base member, a second pocket is formed in the intermediate layer, and the first and second pockets are open to each other.

In preferred embodiments the present disclosure is further directed to an adjustable, anatomical support and wheelchair seat cushion apparatus including a resilient thermoplastic honeycomb seat cushion member and a pivotally attached base member forming a planar base upon which the seat cushion member will rest be deformed when folded about the pivot to engage and lay thereupon. The base member may also be made of one or more layers of a more rigid thermoplastic honeycomb material. Positioned upon the base member and disposed between it and the overlying seat cushion member are user and/or LTC therapist installable, prescriptively sized and shaped pelvic obliquity elements, pommel elements and/or wedge elements, or the like, operative to deform the cushion member when engaged therewith.

Once the pads and/or obliquity, pommel and/or wedge elements are positioned and affixed to the base member, the cushion member is rotated into engagement with the base member. The obliquity, pommel and/or wedge elements deform the cushion member. The assembly is inserted into its fabric cover, a closing zipper or the like is retracted and the cushion apparatus is ready for use. The pad is provided in the back-center portion of the cushion member to protect the user's ischial bone.

An important advantage of the present disclosure is that the thermoplastic elastomeric honeycomb material used in the construction of the apparatus is an anisotropic material having improved pressure relief, stability, compression set resistance, durability and low maintenance characteristics.

Another advantage of the present disclosure is that in fitting the cushion apparatus for a particular user, an LTC therapist may select from a wide variety of preformed shaping elements and cushion positions therefor to customize and individually tailor the cushion apparatus for the user.

Yet another advantage of the present disclosure is that a single size and shape of cushion can be matched with a variety of individually selectable, preformed shaping elements to support the specific requirements of a particular wheelchair user.

Still another advantage of the present disclosure is that the anatomical support apparatus may be constructed from a perforated core thermoplastic elastomer honeycomb panel that is breathable to allow perspiration removal and cooling of the apparatus user.

Another advantage of the present disclosure is that different thermoplastic elastomeric honeycomb core designs and/or multiple panels of different thermoplastic honeycomb core designs may be utilized to maximize design flexibility of the improved anatomical support apparatus.

Still another advantage of the present disclosure is that the thermoplastic elastomeric honeycomb core is fabricated from recyclable materials that are fast drying, and easily disinfected and sterilized.

An object of the present disclosure is to provide an adjustable anatomical support and seat cushion apparatus that can be adapted to accommodate the particular anatomical support needs of a user/patient having postural abnormalities.

Another object of the present disclosure is to provide an improved anatomical support and seat cushion apparatus including at least one thermoplastic elastomer honeycomb cushion panel and a plurality of selectable inserts that serve to conform, support and/or stabilize a wide variety of wheelchair user sitting positions, user anatomies and disabilities.

Another object of the present disclosure is to provide an improved adjustable anatomical support cushion apparatus for providing pelvic and trunk stability for a wheelchair user having postural abnormalities.

Still another object of the present disclosure is to provide an adjustable anatomical support cushion apparatus for maximizing functional activities of daily living for a wheelchair user having postural abnormalities.

Yet another object of the present disclosure is to provide an improved anatomical support cushion apparatus for protecting skin and preventing wounds, and/or promoting the healing of existing wounds suffered by a wheelchair user having postural abnormalities.

A further object of the present disclosure is to provide an adjustable support cushion apparatus for maximizing comfort for a wheelchair user having postural abnormalities.

Another object of the present disclosure is to provide an adjustable anatomical support and seat cushion apparatus for minimizing unwanted skeletal movement by a wheelchair user having postural abnormalities.

Yet another object of the present disclosure is to provide an adjustable support cushion for preventing progression of postural abnormalities.

A still further object of the present disclosure is to provide an adjustable anatomical support apparatus that is breathable to permit cooling of the user.

Another object of the present disclosure is to provide an adjustable anatomical support and seat cushion apparatus that can be tailored to create certain desired cushioning and stabilizing characteristics without having to introduce padding elements such as foams, fluids or other means which add cost or reduce durability.

Still another object of the present disclosure is to provide an adjustable anatomical support apparatus constructed of materials that are fast-drying, and can be easily disinfected and sterilized by chemical wash, microwave treatment, detergent wash, or other means.

These and other objects and advantages of the present disclosure will no doubt become apparent to those skilled in the art after having read the following detailed description of the preferred embodiments which are contained in and illustrated by the various drawing figures.

Further preferred embodiments and/or features of the invention are set out below. The skilled person is aware of the compatibility between features. In a preferred embodiment, the disclosure relates to an adjustable anatomical support and seat cushion apparatus for wheelchairs (hereinafter "apparatus"). The apparatus comprises a base member. The base member is formed of at least one layer of a thermoplastic honeycomb material. The apparatus further comprises a resilient cushion member. The resilient cushion member comprises an upper layer, an intermediate layer and a lower layer. The upper, intermediate and lower layers are of thermoplastic honeycomb material, wherein the resilient cushion member may be formed of said layers. The upper, intermediate and lower layer are bonded together. The upper layer is softer than the intermediate layer. The intermediate layer is softer than the lower layer. The base member has an edge thereof pivotally attached to a corresponding edge of the cushion member. The attachment between the edge of the base member and the corresponding edge of the cushion member comprises a hinge, wherein the cushion member is rotatable between a non-parallel disposition relative to the base member and a parallel disposition relative to the base member. The base member is disposed beneath the lower layer when the cushion member is in the parallel disposition relative to the base member. A first pocket is formed in the lower layer and has an open end facing the base member when the cushion member is in the parallel disposition relative to the base member. The apparatus further comprises at least one pad configured to be positioned within the first pocket of the cushion member. The pad is removable from the first pocket of the cushion member.

In a preferred embodiment, the at least one pad is formed of thermoplastic honeycomb material.

In a further preferred embodiment, the at least one layer of thermoplastic honeycomb material of the base member is more rigid than the layers of thermoplastic honeycomb material of the cushion member.

In a further preferred embodiment, first and second pads are provided, wherein the first pad is softer than the second pad.

In a further preferred embodiment, first, second and third pads are provided, wherein the first pad is softer than the second pad, and the second pad is softer than the third pad.

In a further preferred embodiment, the first pocket is filled when all three pads are seated within the first pocket.

The apparatus further comprises a second pocket formed in the intermediate layer, wherein the first and second pockets are open to each other.

In a further preferred embodiment, a the second pocket formed in the intermediate layer is smaller than a the first pocket formed in the lower layer.

In a further preferred embodiment, the apparatus further comprises a cover removably disposed about the cushion member, the at least one pad, and the base member when the cushion member and the base member are in the parallel disposition.

In a further preferred embodiment, the cover includes an opening configured to allow the cushion member, the pad, and the base member to be inserted into the cover. The cover preferably also comprises a closure disposed about the opening and configured to allow the cushion member, the pad, and the base member to be closedly enveloped within the cover.

In a further preferred embodiment, the apparatus further comprises at least one cushion deforming element configured to be affixed to a surface of the base member generally facing the lower layer. The at least one cushion member deforming element is preferably operative to engage and deform the lower layer when the cushion member is rotated from the non-parallel disposition relative to the base member into the parallel disposition relative to the base member. The at least one cushion deforming element is preferably removable from the base member.

In a further preferred embodiment, the apparatus further comprises a cover removably disposed about the cushion member, the pad or pads, at least one cushion deforming element, and the base member when the cushion member and the base member are in the parallel disposition.

In a further preferred embodiment, the hinge is thermo-compressively formed.

In a further preferred embodiment, the first pocket is proximate to, but spaced from, the hinge.

The apparatus further comprises a second pocket formed in the intermediate layer. The first and second pockets are open to each other. The second pocket formed in the intermediate layer is preferably smaller than the first pocket formed in the lower layer. Preferably, the second pocket formed in the intermediate layer is not filled when the at least one pad is inserted into the first pocket formed in the lower layer.

The organization and manner of the structure and operation of the disclosed embodiments, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings, which are not necessarily drawn to scale, wherein like reference numerals identify like elements in which:.

Referring now to <FIG> of the Drawings which, as pointed out above, depicts a conventional wheelchair <NUM> having disposed thereon but shown without deformation, an adjustable, removable, improved anatomical support cushion assembly <NUM> enclosed in its fabric cover <NUM>. As will be described in greater detail below, the cushion assembly <NUM> is constructed of at least one flexible thermoplastic elastomer honeycomb core panel built in accordance with the present disclosure. It should also be noted that although the cushion apparatus is particularly well suited for wheelchair applications, the cushion apparatus, or analogs thereof, may also be used in a variety of other anatomical support applications (e.g., mattresses, automobile and airline seats, arm rests, etc.).

<FIG> is provided to illustrate optimal user posture when seated in a standard wheelchair.

<FIG> are provided to respectively illustrate abnormal postural conditions identified as pelvic obliquity, anterior pelvic tilt, posterior pelvic tilt and pelvic rotation; all of which are conditions that can be aided through use of the present disclosure.

<FIG> generally depicts the principal components of the seat cushion assembly <NUM> which can be used in a wheelchair in accordance with an embodiment of the present disclosure, and including a multi-layered resilient thermoplastic honeycomb cushion member <NUM> and a pivotally attached base member <NUM> (populated with cushion deforming elements <NUM>, <NUM> and <NUM>) forming a planar base upon which the upper cushion member <NUM> will rest when folded about a pivot or hinge means <NUM> to engage and lay upon the top of the cushion member <NUM> and one or more deforming elements <NUM>, <NUM> and <NUM>. Pivot means <NUM> is preferably a thermo-compressively formed bead-line disposed along mating rear edges <NUM> and <NUM> of the upper cushion member <NUM> and the base member <NUM>, respectively. The base member <NUM> is preferably made of one or more layers of a more rigid thermoplastic honeycomb material.

Positioned upon the base member <NUM> and disposed between it and the overlying cushion member <NUM> are user and/or LTC therapist installable, variously sized and shaped pelvic obliquity elements <NUM> (<FIG>), pommel elements <NUM> (<FIG>) and/or wedge elements <NUM> (<FIG>) all of which are specifically shaped and sized, cushion deforming elements (perhaps prescriptively sized and shaped by an LTC therapist to address a particular user's condition), and intended to be operative to deform or adjust the support capability of the cushion member <NUM> in certain ways when it is engaged therewith. As suggested by the dashed lines <NUM> shown in <FIG>, additional pockets may also be provided in cushion member <NUM> for receiving other cushion adjusting elements (not shown) that may also be inserted into the pockets to further deform the cushion member <NUM> to satisfy certain special needs of a user/patient.

Once the obliquity, pommel and/or wedge elements, or the like, are positioned on and affixed to the base member <NUM>, (and perhaps other elements inserted into the pockets <NUM>), the cushion member <NUM> may be rotated downwardly about the pivot or hinge means <NUM> into engagement therewith and deformed thereby, and the assembly is then ready for insertion into its protective cover <NUM> depicted in <FIG>. It should be noted that the cushion "deformation" may be more or less visible depending upon the softness or resiliency of the cushion and the degree of anatomical adjustment required by the user.

The cover <NUM> is preferably made of a suitable fabric material and may include an upper shell-like part <NUM> and a mating bottom flap part <NUM>. Once the cushion assembly <NUM> is fully assembled, it may be placed on the bottom flap part <NUM> of cover <NUM> and the upper shell-like part <NUM> can be rotated about its fold line <NUM> and into its closed position partially enveloping the cushion assembly <NUM>. Closure of the cover <NUM> may then be completed by zipping an upper zipper part <NUM>, disposed around the lower edge of the shell-like part <NUM>, into engagement with a lower zipper part <NUM> disposed around the exposed perimeter of the bottom flap part <NUM>. At this point the fully assembled cushion apparatus is ready to be placed upon the user/patient's wheelchair for use.

In some cases, use of an ischial pad <NUM> (preferably embodied in the form of another small honeycomb pad of a particular softness, or stiffness, and generally depicted in <FIG>) may also be required to protect the user/patient's tailbone (ischial bone). To provide such protection, a suitably configured ischial pad <NUM> may be inserted into a pocket <NUM> provided in the back-center portion of the upper shell part <NUM> of cover <NUM> to protect the user/patient's ischial bone.

Note also that a second zipper facility <NUM>, or the like, may be provided in cover <NUM> for permitting adjustment of the cover size (expanding or contracting) required to accommodate the number and/or size of the various deforming elements used in the cushion assembly.

In <FIG> a multi-layered cushion member, such as that disclosed in Applicant's prior <CIT> and fully incorporated herein by reference, is shown at <NUM>. In accordance with the present disclosure, the cushion member <NUM> is shown modified to include a lower flap or base member <NUM> as described above. This example is provided to more clearly illustrate attachment of the flap edge <NUM> by thermo-compression bonding along the rear side of the cushion member. Alternatively, the flap edge may be otherwise attached to the upper cushion member <NUM>.

<FIG> illustrates in more detail a particular embodiment of the adjustable wheelchair seat cushion assembly <NUM> having a multi-layered honeycomb seat cushion <NUM>. The multi-layered honeycomb seat cushion <NUM> is constructed using multiple panels or layers of thermoplastic elastomer honeycomb materials. In this embodiment, the upper cushion member <NUM> is comprised of three layers or panels, <NUM>, <NUM>, <NUM> which are bonded together. Each panel <NUM>, <NUM>, <NUM> includes a honeycomb-like core preferably made of bonded together and expanded strips or ribbons of plastic material to which facing sheets of perhaps heavier gauge material are thermo-compression bonded. The illustrated cushion member <NUM> is an anisotropic three-dimensional structure having predetermined degrees of flex along the X, Y and Z axes. Each cell is formed, in part, by four generally S-shaped wall segments of the strips or ribbons each of which is bonded to adjacent strips and shared by an adjacent cell. In addition, each cell shares a double thickness wall segment with two adjacent cells. Note also that as described in our incorporated prior patents, at least some of the strips and facing sheets may be perforated, as shown at <NUM>, to render the cushion breathable and to allow perspiration removal and cooling of the user's body. Moreover, the thermoplastic elastomeric honeycomb materials from which the cushion is fabricated may be recyclable, fast drying, and easily disinfected and sterilized.

Cushion member <NUM> has high tear and tensile strength and is highly resilient, with optimal compression load and shock absorption or distortion characteristics, yet is extremely light weight. Selected combinations of elastomer material, honeycomb cell configurations, core thicknesses and facing material variables will determine the panel's characteristics of softness or hardness, resilient recovery rate and rigidity or flex as required for a particular application. The facing materials can be selected from a wide variety of films, including thermoplastic urethanes, foams, EVAs, rubber, neoprene, elastomer impregnated fibers and various fabrics, etc. The manufacture and fabrication of honeycomb cushions of the type utilized in the present disclosure to make a cushion of the type embodied in applicant's cushion member <NUM> is described in our prior <CIT>.

In accordance with the present disclosure, and as generally described above, the base member <NUM> is preferably made of at least one relatively thin sheet of more rigid honeycomb material, and has a rear edge <NUM> thereof hingedly connected to the back of the cushion member <NUM>, preferably along its rearmost extremity. Removably disposed between the base member <NUM> and the cushion member <NUM>, and preferably attached, by suitable means, such as Velcro or other "hoop and loop materials" or the like, to an upper surface of the base member <NUM> having at predefined locations, are one or more cushion deforming elements selected to define the user support characteristics of the cushion assembly. The cushion deforming elements may be generally described as an assortment of prescriptively sized and shaped pelvic obliquity elements <NUM>, pommel elements <NUM> and/or wedge elements <NUM> as illustrated herein in <FIG>.

These elements are selected, positioned and secured by the user and/or assisting therapist or clinician on the upwardly facing base member surface so as to deform, or alter the support characteristics of the overlying resilient cushion member <NUM> to raise, lower, align, orient or otherwise adjust the user's skeletal components supported by the cushion assembly to provide pelvic and trunk stability, maximize the user's comfort and function during ADLs, protect the user's skin and prevent wounds, assist in the healing of existing wounds, minimize unwanted movement of the user on the cushion surface, correct or accommodate postural abnormalities and/or prevent or mediate progression of postural abnormalities.

As generally described below, these elements are adapted to deform the cushion member <NUM> as it is lowered (folded down) into supporting engagement therewith. The preformed obliquity elements <NUM>, pommel elements <NUM> and/or wedge elements <NUM> are carefully selected and positioned to provide a desired customizing deformation or adjustment of the overlying cushion member <NUM> so that the cushion in turn provides the supporting needs of the user when the assembly is folded into its closed, or folded, configuration.

Once folded, the cushion assembly <NUM> is inserted into an enveloping fabric cover <NUM>, such as that generally illustrated in <FIG>, that is configured to conform to the shape of the cushion assembly and is provided with perimeter zippering means, or the like, to securely house the cushion assembly and maintain it in its closed and functional configuration. As pointed out above, the cover <NUM> may also be provided with internal and/or external first pockets for receiving additional ischial pads, pommels or wedges, etc..

In <FIG>, side views of the above described cushion assembly <NUM> in its open and closed configurations are shown in more detail.

In <FIG> a frontal view is depicted in somewhat exaggerated perspective to emphasize the distortion of the cushion member <NUM> by the several underlying elements.

In <FIG>, a partially broken side view of the fully assembled anatomical support and seat cushion apparatus is shown further illustrating the cushion assembly12 disposed within its fabric cover <NUM>. Note that a closing zipper <NUM>, <NUM> is provided around three sides of the lower edge of the cover, and a second, medially disposed expansion zipper and excess material facility <NUM> is suggested to accommodate an assembly of larger or smaller cushion deforming elements should that be necessary.

<FIG> show a modification to the cushion member <NUM> shown in <FIG>. Each panel <NUM>, <NUM> has a generally uniform height from its lower surface to its upper surface; the heights of the panels <NUM>, <NUM> may be different and each may not have a uniform height. As described herein, the intermediate panel <NUM> has height that varies from its lower surface to its upper surface. The thermoplastic elastomer honeycomb material of the upper panel <NUM> has a first hardness, the thermoplastic elastomer honeycomb material of the intermediate panel <NUM> has a second hardness, and the thermoplastic elastomer honeycomb material of the lower panel <NUM> has a third hardness. The thermoplastic elastomer honeycomb material of the upper panel <NUM> is softer than the thermoplastic elastomer honeycomb material of the intermediate panel <NUM>, and the thermoplastic elastomer honeycomb material of the intermediate panel <NUM> is softer than the thermoplastic elastomer honeycomb material of the lower panel <NUM>. That is, the lower panel <NUM> is more rigid than the intermediate panel <NUM>, and the intermediate panel <NUM> is more rigid than the upper panel <NUM>. As such, when a user sits onto top of the adjustable wheelchair seat cushion assembly <NUM>, the buttocks of the user sink more easily than within the upper panel <NUM>, than within the intermediate or lower panels <NUM>, <NUM>.

A first pocket <NUM> is formed in the back-center portion of the cushion member <NUM>. The first pocket <NUM> extends completely through the lower panel <NUM> from the lower surface thereof to the upper surface thereof such that a portion <NUM> of the lower surface of the intermediate panel <NUM> is exposed when viewed from the lower surface of the cushion member <NUM>. The first pocket <NUM> has a side wall <NUM> formed by the lower panel <NUM>, and an upper wall formed by the portion <NUM> of the lower surface of the intermediate panel <NUM>. A second pocket <NUM> extends from the first pocket <NUM>, and through the intermediate panel <NUM> from the lower surface thereof to the upper surface thereof such that a portion <NUM> of the lower surface of the upper panel <NUM> is exposed when viewed from the lower surface of the cushion member <NUM>. The second pocket <NUM> has a side wall <NUM> formed by the intermediate panel <NUM> and may further be formed by a portion of the lower surface of the intermediate panel <NUM> as described herein, and an upper wall formed by the portion <NUM> of the lower surface of the upper panel <NUM>. The first and second pockets <NUM>, <NUM>, are close to, but spaced from, the pivot or hinge means <NUM>, and are separated from the pivot or hinge means <NUM> by a section <NUM> of at least the lower panel <NUM>. In an embodiment, the intermediate panel <NUM> is not provided between the upper and lower panels <NUM>, <NUM> in the section <NUM> such that the upper and lower panels <NUM>, <NUM> are secured directly together, but a layer of the intermediate panel <NUM> can be provided. As shown, each pocket <NUM>, <NUM> is generally semicircular, however, other shapes may be provided. The second pocket <NUM> is smaller than the first pocket <NUM>.

In an embodiment, the intermediate panel <NUM> has a first portion <NUM> having a height that is generally uniform, and a second portion <NUM> having a height that gradually reduces from the first portion <NUM> to the side wall <NUM> of the second pocket <NUM>. The first portion <NUM> defines a generally planar lower surface and extends from the edges of the intermediate panel <NUM> to the second portion <NUM>. A portion of the lower surface of the first portion <NUM> is exposed in the first pocket <NUM> and forms the upper wall of the first pocket <NUM>. The second portion <NUM> surrounds the side wall <NUM> of the second pocket <NUM> and forms part of the side wall <NUM>. The lower surface of the second portion <NUM> is exposed in the first pocket <NUM>.

The first pocket <NUM> may be left empty to provide first feel to the user/patient's ischial bone. Alternatively, one or more ischial pads <NUM>, <NUM>, <NUM> formed of a thermoplastic elastomer honeycomb material may be seated within the first pocket <NUM> to vary the feel of the adjustable wheelchair seat cushion assembly <NUM> and to protect the user/patient's ischial bone. The one or more ischial pads <NUM>, <NUM>, <NUM> overlay the second pocket <NUM>. As shown, three ischial pads <NUM>, <NUM>, <NUM> of varying hardness are provided. The thermoplastic elastomer honeycomb material of the ischial pad <NUM> has a first hardness, the thermoplastic elastomer honeycomb material of the ischial pad <NUM> has a second hardness, and the thermoplastic elastomer honeycomb material of the ischial pad <NUM> has a third hardness. The thermoplastic elastomer honeycomb material of the second ischial pad <NUM> is harder than the thermoplastic elastomer honeycomb material of the first ischial pad <NUM>, and the thermoplastic elastomer honeycomb material of the third ischial pad <NUM> is harder than the thermoplastic elastomer honeycomb material of the second ischial pad <NUM>. That is, the third ischial pad <NUM> is more rigid than the second ischial pad <NUM>, and the second ischial pad <NUM> is more rigid than the first ischial pad <NUM>. Each ischial pad <NUM>, <NUM>, <NUM> has opposite planar sides and a perimeter shape that mirrors the shape of the wall of the first pocket <NUM> such that the ischial pads <NUM>, <NUM>, <NUM> fit snugly within the first pocket <NUM>.

In an embodiment, each ischial pad <NUM>, <NUM>, <NUM> has a height from its upper surface to its lower surface that is less than the height of the first pocket <NUM> such that when a single one of the ischial pads <NUM>, <NUM>, <NUM> is inserted into the first pocket <NUM>, the first pocket <NUM> is not completely filled in the height direction. In the embodiment as shown, when all three ischial pads <NUM>, <NUM>, <NUM> are inserted into the first pocket <NUM>, the first pocket <NUM> is completely filled in the height direction. The heights of the ischial pads <NUM>, <NUM>, <NUM> can be varied such so that the first pocket <NUM> is filled in the height direction when two of the ischial pads are inserted therein, or so that the first pocket <NUM> is filled in the height direction when three of the ischial pads are inserted therein. The ischial pads <NUM>, <NUM>, <NUM> may have the same heights or different heights.

When the seat cushion <NUM> is folded over onto the base member <NUM> (which may be populated with cushion deforming elements <NUM>, <NUM> and <NUM>) about the pivot or hinge means <NUM> to engage and lay upon the top of the cushion member <NUM>, the first and second pockets <NUM>, <NUM> face the upper surface of the base member <NUM>. The deforming elements <NUM>, <NUM> and <NUM> are preferably not positioned underneath the first and second pockets <NUM>, <NUM>. The ischial pads <NUM>, <NUM>, <NUM> are trapped between the seat cushion <NUM> and the base member <NUM> to secure the ischial pads <NUM>, <NUM>, <NUM> in place.

In an embodiment, the base member <NUM> has a hardness which is harder than the hardness any of the panels <NUM>, <NUM>, <NUM>. In an embodiment, the base member <NUM> has a hardness which is the same as the hardness of the lower panel <NUM>.

The feel on the buttocks of the user/patient is varied depending upon whether, none, one, two or three ischial pads <NUM>, <NUM>, <NUM> are inserted into the first pocket <NUM>. In addition, two or more of the same hardness ischial pads can be inserted into the first pocket <NUM>. Upon at least initial insertion(s), the ischial pads <NUM>, <NUM>, <NUM> do not enter into/fill the second pocket <NUM>. When the user/patient's ischial bone is positioned thereabove, the user/patient's ischial bone can move into the second pocket <NUM> and be protected.

Claim 1:
An adjustable anatomical support and seat cushion apparatus for wheelchairs, comprising:
a base member (<NUM>) formed of at least one layer of a thermoplastic honeycomb material;
a resilient cushion member (<NUM>) formed of an upper layer (<NUM>) of thermoplastic honeycomb material, an intermediate layer (<NUM>) of thermoplastic honeycomb material, and a lower layer (<NUM>) of thermoplastic honeycomb material, the layers being bonded together, the base member (<NUM>) having an edge thereof pivotally attached to a corresponding edge of the cushion member (<NUM>) at a hinge (<NUM>), the cushion member (<NUM>) being rotatable between a non-parallel disposition relative to the base member (<NUM>) and a parallel disposition relative to the base member (<NUM>), wherein the base member (<NUM>) is disposed beneath the lower layer (<NUM>) when the cushion member (<NUM>) is in the parallel disposition relative to the base member (<NUM>), wherein a first pocket (<NUM>) is formed in the lower layer (<NUM>);
and
at least one pad (<NUM>/<NUM>/<NUM>) configured to be positioned within the first pocket (<NUM>) of the cushion member (<NUM>), the at least one pad (<NUM>/<NUM>/<NUM>) being removable from the first pocket (<NUM>) of the cushion member (<NUM>)
characterized in that
the upper layer (<NUM>) is softer than the intermediate layer (<NUM>), and the intermediate layer (<NUM>) is softer than the lower layer (<NUM>),
wherein the first pocket (<NUM>) has an open end facing the base member (<NUM>) when the cushion member (<NUM>) is in the parallel disposition relative to the base member (<NUM>);
a second pocket (<NUM>) is formed in the intermediate layer (<NUM>), and the first and second pockets (<NUM>, <NUM>) are open to each other.