External fixator assembly

Abstract

A support structure for use with an external fixator assembly including, but not limited to, a fixator assembly for the ankle area of the body which may further include an ankle stabilization portion. The support structure is similar in function but distinguishable in structure from a “halo-ring” and comprises a base having a substantially annular configuration and being operatively disposed in at least partially surrounding relation to a leg area which corresponds to the stabilized ankle area. An extension assembly includes at least one but preferably a plurality of two elongated extension members extending outwardly from the base and in spaced relation to and substantially aligned with the ankle stabilization portion. The base and the two extension members are structured for connection to a plurality of struts which may be variably and selectively disposed in interconnecting relation to the ankle stabilization area and/or other portions of the external fixator assembly.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is directed to a support structure similar in function but distinguishable in structure to a halo-type support ring adapted for use as an operative component of an external fixation assembly for an ankle or other area of the patient's body. The support structure includes an annular base dimensioned and configured for disposition in surrounding relation to a leg area associated with the ankle being stabilized. An extension assembly comprising a plurality of extension members is connected to the base, wherein the base and extension members are structured for connection to one or more strut members disposed in interconnecting relation to and between the support structure and the other components of the external fixator assembly.

2. Description of the Related Art

In the medical treatment of pathologies including, but not limited to, injuries, fractures, etc. to the bone and joints, external fixator assemblies are commonly used to maintain segments of the bone in an intended and/or required stabilized orientation. By way of example, fixator assemblies of the type described may be utilized to treat the fusion of bone tissue as well soft tissue injuries, and situations involving a union of bones which otherwise are difficult to heal. As such, known or conventional fixator assemblies vary in structure, dimension and configuration and are correspondingly adapted to be used with various portions of the body to which they are attached.

Typical fixator structures include one or more connecting bars or rods as well a plurality of clamps for adjustably securing fixation pins, wires, etc. to the bone portions being affected. Further, transfixion pins or wires of the types commonly utilized may extend completely through the bony tissue or may be anchored therein, such as when the long bones of the leg are involved directly or indirectly with the treatment or healing procedure. Further, the term “transfixion member” is generally recognized in the medical field as including the describing of elongated pins which extend completely or at least partially through the bony tissue involved. In contrast, smaller, thicker “half pins” may be utilized in substantially the same manner to stabilize affected tissue but being of a length insufficient to extend completely through the affected bone, joint, etc. This term may also be used in a more generic sense in referring to stabilizing devices, other than pins, such as wires, reduction wires, screws, clamps, etc.

In addition, known external fixator assemblies of the type described may also include support rings which encircle a corresponding body member, wherein such rings or like support members serve as a supportive base to facilitate proper location of the aforementioned transfixion members. Accordingly, it is commonly understood in the medical profession that fixator assemblies are used to maintain proper orientation of one or more of bones or bone segments relative to one another to facilitate healing or alignment.

However, the proper stabilization of tissue typically associated with the joint areas of a patient's body such as, but not limited to, the ankle joint as well as the wrist and other smaller bones associated with the hand involves additional considerations. In particular when dealing with the ankle area and the associated tissue serving to interconnect the foot to the lower portion of the leg, the fixator clamps or fixation clamps support blocks are frequently connected to an encircling halo-ring or like support member. These devices are mounted on the ring or other support member to properly position a transfixion pin or like member at a proper height or corresponding distance above the supporting ring in order to engage and thereby properly orient the affected bones of the ankle joint to the foot. In utilizing these support blocks, transfixion clamps, etc., one commonly recognized problem or disadvantage associated therewith is the possibility these devices obscuring important or necessary portions of the ankle joint when X-rayed. In addition, the proper placement of one or more of such clamps, support blocks, etc. is time consuming for medical personnel and may lack a certain versatility and/or accuracy associated with the accurate placement of a transfixion pin or like transfixion member in the fixed orientation or otherwise support of the various bones of the ankle joint.

Accordingly there is a need in the medical profession for a support assembly which is at least minimally similar in function, but clearly distinguishable in structure, from a known halo-type ring support structures. Such an improved support structure allows greater versatility in the positioning of interconnecting struts serving to interconnect and support various components of an external fixator assembly in their intended operative position. Further, the dimension, configuration and overall structure of such a proposed support structure is such as to be usable with an external fixator assembly of the type used to stabilize the ankle area of the patient. As such, the support may be disposed in interconnected, spaced relation to an ankle stabilization portion of the external fixator assembly and in surrounding relation to an adjacent leg area associated with the ankle being stabilized. The proposed support assembly of the present invention is structured to facilitate the support and connection of a plurality of interconnecting struts. Further, the support structure is also structured to have mounted thereon and/or connected thereto a plurality of transfixion members which extend radially inward from the proposed support structure into engaging relation to the relatively long bones of the corresponding leg area.

Accordingly there is a need in the medical profession for an a support structure component useable as part of an external fixator assembly which more efficiently stabilizes the hard tissue associated with the foot and ankle areas and/or the associated bones of the lower leg.

SUMMARY OF THE INVENTION

The present invention is directed to a support structure for use with or as part of an external fixator assembly of the type specifically, but not exclusively, intended for the stabilization of an ankle area of the body. As such, the various embodiments of the support structure of the present invention are operatively disposed to function somewhat similarly to the known halo-type support ring, as generally set forth above. However, the structural features of the support ring structure of the present invention are clearly distinguishable from known or conventional halo-type rings, as set forth in greater detail hereinafter.

As referred to herein, the term “ankle area” refers to and is intended to describe the ankle joint, as well as bones and associated tissue of the foot and lower portions of the leg bones including the fibula and tibia. Further, in properly describing the intended position and orientation of the various preferred embodiments of the support structure of the present invention and the remainder of the external fixator assembly associated therewith, terminology including “length of the ankle area” and/or “height of the ankle area” may be utilized synonymously. These terms are meant to refer to the general distance between the bottom of the foot and an area of the lower part of the leg above the ankle joint. Further the ankle area, as used herein, is meant to be descriptive of the bones and other tissue associated with the foot, ankle joint and lower leg which serve to facilitate the functioning of the ankle joint and intended, relative movements of the corresponding foot and leg connected to the ankle joint.

Accordingly, the support structure of the present is used independently of or in combination with an external fixator assembly which may further comprise an ankle stabilization portion. The ankle stabilization portion is disposed adjacent the ankle area and foot and is structured to support at least one transfixion pin or like transfixion member in operative engagement with the bones or other associated tissue associated with the ankle area. Moreover, the support structure of the present invention comprises a base preferably having a continuous, annular configuration or be otherwise configured and dimensioned to at least partially, but in most applications completely surround the leg area of a patient's body which is substantially adjacent to the ankle area being stabilized.

Further, the support structure of the present invention includes an extension assembly comprising at least one but more practically a plurality of extension members or arms extending outwardly from the base. Each of the arms is elongated to a sufficient degree that, when combined with the corresponding dimensions of the base, extend along at least a portion and/or a majority of the length of corresponding, spaced apart portions of the ankle stabilization portion of the external fixator assembly. In addition, a plurality of apertures or through holes are disposed about the continuous length of the base and also along the length of the extension members. These apertures will serve as connecting sites for at least one, but more practically, a plurality of elongated studs. As described herein, the one or more studs serve to interconnect the support structure of the present invention with the ankle stabilization portion as well as any additional conventional halo-type rings and/or additional support structures.

Therefore, the interconnecting struts serve to place both the ankle stabilization portion and/or other, conventional halo-type rings in spaced relation to the support structure as these various components extend along the length of the ankle area or leg upwardly from the position of the ankle stabilization portion adjacent the ankle area being stabilized. Further, the plurality of apertures defining the connecting sites for the struts are disposed such that the plurality of struts may be disposed at a variety of different locations in order to provide greater versatility to the medical personnel when placing the struts and the various components of the external fixator assembly in order to eliminate the possibility of interference with X-rays views, which are typically required.

Other features associated with the support assembly of the present invention include the plurality of preferably two extension members extending outwardly from the base in a common direction and in spaced relation to one another. In at least one preferred embodiment, the two extension members or arms may also be disposed in parallel relation to one another and may be further disposed in substantially coplanar relation to one another and/or to the base. In order to provide sufficient structural integrity to the two extension members, at least one embodiment of the support structure includes a brace assembly. The brace assembly preferably comprises at least two brace segments each disposed in interconnecting, reinforcing relation between an exterior periphery of the base and a corresponding peripheral edge or other appropriate portion of a different one of the extension members or arms.

As represented hereinafter in greater detail, the external fixator assembly, including the support structure of the present invention, is structured to connect one or more transfixion pins or like transfixion members so as to extend transversely inward and into stabilizing engagement with the leg bone(s) or other tissue associated with the ankle area at various points along the height or length of the leg and/or ankle area. Further, each of the one or more transfixion pins can be connected to a plurality of different locations along the length thereof. Therefore the disposition of the base and extension assembly of the support structure as well as the structure of at least some of the remainder of the external fixation assembly provides significant versatility in positioning each of the one or more transfixion pins or members at any one of a plurality of different locations relative to the leg and associated ankle area being stabilized.

Therefore, the positioning of the transfixion pin(s) or member(s) into stabilizing engagement with intended tissue of the leg and ankle area, in the manner described herein, eliminates or significantly reduces the need for conventional support blocks or clamps to connect the transfixion pin(s). As set forth above, the use of such known devices and procedures for orienting of the transfixion pins relative to a predetermined body part is time consuming and has a tendency to obscure X-rays or other viewing facilities of the body part. Therefore the use of the various preferred embodiments of the present invention eliminate or significantly reduce such known and well recognized disadvantages.

These and other objects, features and advantages of the present invention will become clearer when the drawings as well as the detailed description are taken into consideration.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of a support structure of the present invention.

FIG. 2 is a perspective view of the support structure of the present invention as represented in the embodiment of FIG. 1 incorporated within and at least partially defining an external fixator assembly of the type adapted for use in the stabilization of an ankle area.

FIG. 3 is a perspective view of the embodiment of FIG. 2 in at least partially schematic form.

FIG. 4 is a side view of the embodiment of FIG. 3.

FIG. 5 is a side view in partial cutaway and schematic form of an external fixator assembly modified from that of FIGS. 2 and 3 operatively positioned relative to an ankle area of a patient.

FIG. 6 is a top view in partial cutaway and schematic form of the fixator assembly of FIG. 5 operatively positioned relative to the foot or lower leg portion of an ankle area of a patient.

Like reference numerals refer to like parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As represented in the accompanying Figures, the support assembly of the present invention is generally indicated as 100 and is structurally distinguishable from the conventional halo support ring generally indicated as 102 in the embodiments of FIGS. 2-4. Moreover, each of a plurality of preferred embodiments of the support structure ring 100 of the present invention is adaptable for use in combination with an external fixation assembly generally indicated as 104 in the embodiments of FIGS. 2-4. Further, as will also be discussed in greater detail hereinafter, the external fixator assembly 104 is structured to be operatively positioned and used in a location substantially adjacent to an ankle area generally indicated as 12 in FIG. 5 of a patient. As set forth above, the ankle area 12 is meant to be descriptive of substantially the entire area represented in FIG. 5, which includes the ankle joint, foot, corresponding portions of the leg bones, including the fibula and tibia, as well as the associated components and tissue. In addition, the terms “height” and “length” of the ankle area 12 are used synonymously herein and refer to the distance from substantially the bottom of the foot, as at 14, to at least a portion the long bones of the leg, as at 16, 16′.

Therefore, with primary reference to FIGS. 1, the support assembly 100 of the present invention includes a base generally indicated as 106 preferably having an annular configuration and an open interior 108. The open interior 108, as well as the circumferential dimension of the base 106, are sufficient to dispose the base 106 in substantially surrounding relation to the leg portion associated with the leg bones 16, 16′ adjacent the ankle portion 12 being stabilized, as schematically represented in FIG. 5. In addition the support structure 100 also includes an extension assembly generally indicated as 110 comprising at least one but preferably a plurality of two extension members or extension legs 112 and 114. Each of the extension members 112 and 114 is integrally or otherwise fixedly connected to and extends outwardly from a different, opposite end or side of the base 106 preferably, but not necessarily, in a substantially common direction. As such, the common directional orientation of the extension members 112 and 114 serves to dispose these members in spaced relation to one another. Moreover, in at least one embodiment the extension members 112 and 114 may be disposed in substantially parallel relation to one another.

Further, the structure of the extension assembly 110 may be defined by the extension members 112 and 114 being disposed in substantially coplanar relation to the base 106 and/or in coplanar relation to one another. However, the intended operability and versatility relative to a position by the support structure 100 allows the extension members 112 and 114 to be disposed in non-coplanar relation to the base 106 and/or in non-coplanar relation to one another. Accordingly, the extension members 112 and 114 may be disposed in coplanar relation to one another but out of coplanar relation to the base 106. Also the parallel, spaced apart relation of the extension members 112 and 114 may vary from that represented in FIG. 1 to a substantially non-coplanar, parallel relation there between.

Additional structural features of the support structure 100, including both the base 106 and each of the plurality of preferably two extension members or arms 112 and 114 including a plurality of apertures or open, through holes 40. The apertures 40 define a plurality of connection sites and structures which facilitate the attachment and/or mounting of a plurality of supporting studs 115 in a variety of operative positions relative to the support structure 100 and the remaining components of the external fixation assembly 104, including the ankle stabilization portion 18 and the substantially conventional halo-support ring 102. Further, the plurality of apertures 40 defining the aforementioned connection sites are also adaptable to facilitate connection, mounting and support of a plurality of transfixion members 36, as represented in FIGS. 5 and 6. As such, when applied or mounted on the support structure 100, including the base 106 and the extension members 112 and 114, the transfixion members 36 may extend radially inward into an engagement with the leg bone 16, 16′, surrounded by the base 106. As such, the support structure 100 will serve to support, securely position and thereby stabilize the external fixator assembly 104, as well as the various components thereof, including the ankle stabilization portion 18 and the conventional halo-type support ring 104.

Other structural features of the support structure 100 include the provision of a brace assembly generally indicated as 120. The brace assembly 120 includes a plurality of brace segments 122 equal in number to that of the plurality of preferably two extension members 112 and 114. As such, the brace segments 122 are disposed in interconnecting, supporting and reinforcing relation between the exterior periphery of the base 106, as at 124, and a corresponding inner peripheral side or edge 126 of different ones of the extension members 112 and 114. As represented, each of the brace segments 122 may be integrally or otherwise fixedly connected to the base 106 and the corresponding extension member 112 and 114 in their respective reinforcing positions.

For purposes of clarity the various operative and/or structural components of one type of external fixator assembly are represented in appropriate detail in FIGS. 5 and 6. Accordingly, the external fixator assembly 104 may comprise an ankle stabilization portion 18 and possibly a conventional halo-type support ring 102. As will be apparent in the description of the fixator assembly 104 hereinafter provided, the ankle stabilization portion 18 may include one or more contoured segments 22 and 22′ operatively positioned relative to the ankle area 12. Further, the one or more contoured segments utilized may be selected from a larger plurality of contoured segments 22, 22′, etc., which may differ from one another at least in dimension and configuration, as represented in the structural modifications of the external fixator assembly 18 represented in FIGS. 2 through 4. With primary reference to FIG. 5, the base segment 20, defining at least a portion of the ankle stabilization portion 18, preferably includes a curvilinear configuration which may be more specifically defined by an arcuate or semicircular shape. As such, the base segment 20 terminates in oppositely disposed free ends 23 and 23′. Further, a plurality of apertures or other appropriate structure 25 are positioned substantially along the length of the base segment 20 and are provided to facilitate the connection of one or more struts 115 to the base segment 20 preferably using fixation bolts, which are not shown for purposes of clarity. Such struts 115 and interconnecting fixation bolts are well-known in the medical profession and are used to support and/or dispose the ankle stabilization portion 18 in a stabilized position relative to the ankle area 12. As set forth above and represented in the various Figures, the struts 115 serve to interconnect the components of the external fixator assembly 104, including the conventional halo-type ring 102 and the support structure 100 located above the ankle area 12, along the length of the leg and in surrounding relation to the bones 16 and 16′.

Accordingly, as represented in FIGS. 5 and 6, the base segment 20 is disposed in at least partially surrounding, spaced relation to a portion of the ankle area 12, such as in the vicinity of the heel 12′. For purposes of clarity, the plurality of apertures or like connecting facilities 25 are not pictured in FIG. 5 but are in FIG. 2 and are intended to be present therein during the actual practical application or use of the fixator assembly 104. With further reference to both FIGS. 5 and 6, operative placement and use of the fixator assembly 104 comprises the supported disposition of at least one contoured segment 22 or 22′ adjacent to an appropriate side of the ankle area 12. More specifically, contoured segment 22′, having the smaller or lesser protruding contoured portion 30 is normally placed adjacent the lateral side of the foot and/or ankle area 12. In cooperation therewith, the contoured segment 22, having the larger or greater outwardly protruding portion 30 is normally, but not exclusively, appropriately positioned adjacent the medial side of the foot and/or ankle area 12.

As represented in FIG. 5, operative disposition and use of the fixator assembly 10 may comprise utilization of two of the contoured segments 22 and 22′, wherein each is connected to correspondingly disposed ends 23 and 23′ of the base segment 20. It is noted that the interconnection of the one or more contoured segments 22 and 22′ to the base segment 20 may be removably connected, in a stable manner, through the use of appropriate connectors as at 29.

It is emphasized that common structural features do exist between each of a plurality of contoured segments 22, 22′, etc. However, each of a possible larger number of contoured segments 22, 22′, etc. may vary in dimension and configuration to accommodate accurate placement of a plurality of transfixion wires or members 36 relative to different portions of the ankle area 12.

Accordingly, each of the contoured segments 22, 22′, etc. includes a contoured portion generally indicated as 30 disposed in spaced relation to at least one end 32 thereof, but more practically in spaced relation to opposite ends 32 and 32′ thereof. As such, the contoured segment 30, in at least one preferred embodiment of the fixator assembly 10, is disposed intermediate the opposite ends 32 and 32′. Also, one of these opposite ends, such as at 32, is fixedly or removably connected to a correspondingly disposed end 23 of the base segment 20. Further, each of the contoured segments 22, 22′, etc. comprise the contoured portion 30 having a substantially angular configuration as it protrudes transversely outward from a remainder of the length of the corresponding contoured segment 22, 22′, etc. Moreover, each of the contoured portions 30 terminates at what may be generally referred to as an apex or upper portion of the contoured segment 30, as at 32. Therefore, when one or more of the contoured segments 22, 22′, etc. are operatively positioned, a contoured portion 30 of each of the one or more contoured segments 22, 22′, etc. extends transversely outward from a remainder of the corresponding contoured segment 22 or 22′ along the height or length of the ankle area 12 as best demonstrated in FIG. 1. Accordingly, each of the contoured segments 22, 22′, etc. are structured to be connected to and support one or more of a plurality of transfixion members or transfixion wires 36, as represented in FIGS. 5 and 6. As such, each of the one or more transfixion wires or pins 36 extend transversely inward, toward the appropriate portion of the ankle area 12, from any one of a plurality of possible locations on the contoured segment 22, 22′, etc. including, but not limited to, being connected to the contoured portion 30 or other portions of the length of the corresponding contoured segment.

As such, the contoured portions 30 of each of the contoured segments 22 and 22′ will be located adjacent and in operative relation to an at least minimally different portion of the various bones or other tissue of the ankle area 12. This in turn will facilitate and enhance the versatility of accurately and efficiently placing one or more transfixion wires, pins or like members 36 into engaging, stabilizing relation to the intended bones or other tissue of the ankle area 12. More specifically, as each of the contoured portions 30 of each contoured segment 22, 22′, etc. extend transversely outward from the remainder of the length of the corresponding contoured segments 22, 22′, etc., the transversely inward ability to position one or more of the transfixion members 36 into engaging relation with appropriate tissue of the ankle area 12.

Additional structural details of each of the plurality of contoured segments 22, 22′, etc. include the provision of a plurality of apertures 40, or other appropriately structured connecting sites, along the length of the contoured portion 30 as well as the remainder of the length of the corresponding contoured segment 22, 22′ etc. These apertures *40 facilitate the interconnection of the one or more transfixion members 36 thereto, such that the one or more transfixion members 36 may be located at any one of a plurality of locations along the contoured portion 30 as well as the remainder of the length of the contoured segment 22, 22′, etc. This further adds in the versatility and accurate placement of the transfixion member 36 along the entire length of the corresponding contoured segments 22, 22′, etc. Also, when each of the contoured segments 22, 22′, etc. are fixedly but removably connected to the appropriate ends as at 23 and 23′ of the base segment 20, additional apertures or other appropriate structures may be provided to facilitate placement of an appropriate connector 29, as represented in FIG. 5. It is further emphasized that when two contoured segments are used, as in the embodiment of FIG. 5, they may comprise different or substantially equivalent dimensions and configurations, dependent on the medical requirements in the stabilization or other treatment of the ankle area 12.

Since many modifications, variations and changes in detail can be made to the described preferred embodiment of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents.

Now that the invention has been described,

Claims

1. A support structure for use in an external fixator assembly, said support structure comprising:

a base having a substantially annular configuration and dimensioned for operative disposition in at least partially surrounding relation to a leg area of an individual,

an extension assembly connected to said base and extending outwardly therefrom, and

said base and said extension assembly structured for connection to at least one strut along a length of said base and said extension assembly.

2. A support structure as recited in claim 1 wherein said extension assembly comprises at least one extension member having an elongated configuration.

3. A support structure as recited in claim 2 wherein said one extension member is disposed in substantially coplanar relation to said base.

4. A support structure as recited in claim 1 wherein said extension assembly is disposed in substantially coplanar relation to said base.

5. A support structure as recited in claim 1 wherein said extension assembly comprises a plurality of elongated extension members.

6. A support structure as recited in claim 5 wherein said base and at least two of said plurality of extension members are each structured for connection to at least one strut and disposition of the one strut in interconnecting relation to a remainder of the external fixator assembly.

7. A support structure as recited in claim 5 wherein said two extension members extend outwardly from said base in a substantially common direction.

8. A support structure as recited in claim 7 wherein said two extension members and corresponding portions of said base are collectively of sufficient length to extend along and its spaced relation to at least a majority of a length of an ankle stabilizing portion of said external fixator assembly.

9. A support structure as recited in claim 7 wherein each of said two extension members is disposed in substantially coplanar relation to said base.

10. A support structure as recited in claim 7 wherein said two extension members are disposed in substantially coplanar relation to one another.

11. A support structure as recited in claim 10 wherein said two extension members are disposed in parallel relation to one another.

12. A support structure as recited in claim 1 wherein said extension assembly comprises at least two elongated extension members each connected to an opposite side of said base.

13. A support structure as recited in claim 12 wherein said two extension members and corresponding portions of said base to which said two extension members are connected are collectively of sufficient length to extend along and in spaced relation to at least a majority of a length of an ankle stabilizing portion of said external fixator assembly.

14. A support structure as recited in claim 13 wherein said base and said two extension members are each structured for connection to at least one strut and disposition of the one strut in interconnecting relation to a remainder of the external fixator assembly.

15. A support structure as recited in claim 14 wherein each of said two extension members is disposed in substantially coplanar relation to said base.

16. A support structure for use with an external fixator assembly for an ankle area of the body, said support structure comprising:

a base configured for operative disposition in at least partially surrounding relation to a correspondingly disposed leg area of the body,

an extension assembly including a plurality of elongated extension members extending outwardly from said base in spaced relation to and along a length of a remainder of the fixation assembly, and

said base and at least two of said plurality of extension members each structured for connection to at least one strut and disposition of this one strut in interconnecting relation to an ankle stabilizing portion of the external fixator assembly.

17. A support structure as recited in claim 16 wherein said two extension members are each connected to a different, opposite side of said base.

18. A support structure as recited in claim 17 wherein said base and said two extension members include a plurality of apertures extending along respective lengths thereof, said plurality of apertures disposed and structured for connection to a plurality of struts and disposition of the plurality of struts in interconnecting relation to the ankle stabilizing portion of the external fixator assembly.

19. A support structure as recited in claim 17 wherein each of said two extension members is disposed in substantially coplanar relation to said base.

20. A support structure as recited in claim 19 wherein said two extension members are disposed in parallel relation to one another.

21. A support structure as recited in claim 20 wherein said two extension members extend outwardly from said base in a substantially common direction.

22. A support structure as recited in claim 17 further comprising a brace assembly disposed in interconnecting relation between said base and each of said two extension members.

23. A support structure as recited in claim 21 wherein said brace assembly comprises at least two brace segments each connected in interconnecting relation between said base and a different one of said two extension members.

24. A support structure as recited in claim 23 wherein each of said brace segments is interconnected between a different one of said two extension members and an outer periphery of said base.