WO2004026158A1

WO2004026158A1 - Fixation device

Info

Publication number: WO2004026158A1
Application number: PCT/AU2003/001207
Authority: WO
Inventors: Ian Ross Griggs
Original assignee: Ian Ross Griggs
Priority date: 2002-09-20
Filing date: 2003-09-16
Publication date: 2004-04-01
Also published as: AU2002951653A0

Abstract

A fixation device (10) includes a hollow outer member (12) and an inner member (14) that can be slideably inserted into outer member (12). The fixation device (10) further includes a plurality of pins (16, 18) The outer member (12) further includes a plurality of openings (24, 26). The inner member (14) is provided with a plurality of pin receiving means which include a plurality of grooves or cavities formed in the inner member (14). The pin receiving means for pin (16) comprises a groove (32). Groove (32) is of increasing depth in a direction from the first end (20) of pin (16) to the second end (22) of pin (16). Spherical enlargement (34) of groove (32) partially encases the second end (22) such that the second end (22) of pin (16) cannot move longitudinally along the inner member. The groove (32) is also shaped and sized such that first end (20) of pin (16) comes into contact with edge (28) of opening (24). Continued movement of the inner member (14) causes the pins (16, 18) to rotate outwardly about the second end and ends thereof and to extend the pins.

Description

Fixation Device

Field of the invention

The present invention relates to a fixation device. The fixation device can be used to fix two or more components or members together, as an anchoring or locking device in the construction industry, the mountain climbing industry or the lock industry, in the construction of pylons or other structural members, or even as an intramedullary bone fixation device.

Background of the invention

In my co-pending Australian patent application no. 12539/00, the entire contents of which are herein incorporated by cross-reference, I describe a fixation device or intramedullary bone fixation device in which a hollow elongate member is provided with a number of holes in its side wall. An inner member is slid into the hollow elongate members. The inner member carries or supports a number of pins. The pins are positioned transversely to the longitudinal areas of the inner member. The pins are moved from a retracted position to an extended position in which the pins extend through respective holes in the hollow elongate member by causing relative rotation between the inner member and the hollow elongate member.

It is an object of the present invention to provide a fixation device of alternative construction.

Summary of the invention

In a first aspect, the present invention provides a fixation device comprising a hollow outer member, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, at least one region defined between the inner member and the hollow outer member such that at least a part of a pin can fit between the inner member and the hollow outer member, loading means in the hollow outer member for loading the at least one pin, and wherein a pin is loaded by entering the pin into the loading means such that the pin is received in an at least one region and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement of the inner member and the hollow outer member.

The at least one region defined between the inner member and the hollow outer member that allows at least a part of a pin to fit between the inner member and the hollow outer member preferably includes one or more portions on the inner member that, together with an inner wall of the hollow outer member, define the at least one region. The one or more portions on the inner member may include sloped region(s), frusto- conical region(s), region(s) of reduced diameter, slot(s), groove(s), cavities or depressions. Preferably, the inner member includes one or more pin receiving means that, together with the hollow outer member, define the one or more regions.

Alternatively, the at least one region may be defined by one or more portions on the hollow outer member that, together with the inner member, define the one or more regions.

Similarly, both the inner member and the hollow outer member may include one or more portions that together define the one or more regions.

The at least one region preferably restrains an end of the pin against movement in one longitudinal direction when a pin is positioned in the region.

In a most preferred embodiment, the one or more regions are defined at least in part by pin receiving means on the inner member. The pin receiving means on the inner member preferably comprise one or more sloped regions, frusto-conical regions, regions of reduced diameter, slots, grooves, cavities or depressions on the inner member. The pin receiving means are suitably formed on the outer surface of the inner member. The pin receiving means are preferably shaped such that each pin fits into a respective pin receiving means. More preferably, the pin receiving means are of a generally complementary shape to the shape of the pins.

It is especially preferred that the pin receiving means is shaped such that the second end of the pin does not extend above a level of an outermost surface of the inner member and the first end of the pin protrudes just above an outermost surface of the inner member. In this fashion, the first end can come into contact with an edge of a loading means or an opening in the hollow outer member during extension of the pins. This assists in forcing the pins towards the extended position by continued longitudinal relative movement between the hollow outer member and the inner member.

Most suitably, the pin receiving means is shaped such that a second end of the pin is substantially restrained against longitudinal movement when positioned in the pin receiving means whilst allowing for rotation of the pin about the second end.

The inner member is preferably provided with a plurality of pin receiving means. The plurality of pin receiving means may be provided in "rows" in which two or more pin receiving means are positioned around the periphery of the inner member at discrete longitudinal positions.

In one embodiment, the pin extends through the loading means when in the extended position.

In another embodiment, the hollow outer member includes at least one opening and the pin or pins extend through associated ones of the at least one opening when in the extended position.

The device preferably includes a plurality of pins. In this embodiment the device may also include a plurality of loading means or a plurality of openings in the hollow outer member or both. It will be appreciated that the inner member should also include a plurality of pin receiving means in this embodiment. Most suitably, each pin has an associated pin receiving means and a loading means or opening through which each pin can extend when in the extended position.

The pin preferably has an enlargement at its second end. The enlargement is most suitably a round enlargement. The second end of the pin suitably acts as an axle or pivot around which the pin rotates when it is moved from the retracted position to the extended position.

The first end of the pin is advantageously bevelled or sharpened. It may even form a point or a sharpened end. This assists in preventing the first end from becoming engaged with or stuck on the hollow outer member during extension of the pin. The pin loading means preferably includes at least one opening in the side wall of the hollow outer member. The pin loading means may be shaped such that it is of generally complementary shape to a cross-sectional shape of the pins.

In one embodiment, the pin loading means is in communication with an opening through which the pin extends when in the extended position and the hollow outer member is provided with pin retaining means for retaining the pin when it is positioned such that a second end of the pin is not in alignment with the pin loading means. The pin retaining means may comprise a bridge, flange, wing or other suitably shape formed in the hollow outer member.

In another embodiment, the loading means includes an opening through which an enlarged end of a pin can pass, the loading means further including a part through which a shank portion of the pin can pass but which is smaller than the enlarged end of the pin. The loading means of this embodiment also suitably includes a longitudinal slot. In one embodiment, the opening through which the enlarged end of the pin can pass is positioned an end of the longitudinal slot. In another embodiment, the opening through which the enlarged end of the pin can pass is positioned to or at a side of the longitudinal slot.

In another embodiment of the first aspect of the invention, the device is provided with pin retaining means for retaining the pins in position. The pin retaining means may comprise a thin membrane or a strap or an elastic member extending around the hollow outer member, preferably being positioned such that it overlies at least part of the pin loading means. Alternatively, the pin retaining means may comprise grease or other viscous fluid or an adhesive of low adhesive power to hold the pins in the pin receiving means.

In a second aspect, the present invention provides a fixation device comprising a hollow outer member having at least one hole in a side wall thereof, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, the inner member having at least one pin receiving means for receiving a pin and retaining means for retaining the at least one pin in said pin receiving means, wherein in use the inner member has the at least one pin positioned in respective ones of the at least one pin receiving means and the at least one pin is retained in place by the retaining means and the inner member is thereafter inserted into the hollow outer member and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement of the inner member and the hollow outer member.

The retaining means preferably does not connect the pins to the inner member but rather retains the pins in close proximity to the inner member. The retaining means does not comprise a permanent means of affixing the pine to the inner member.

In the second aspect of the invention, the pins can be positioned in respective pin receiving means prior to the inner member being inserted into the hollow outer member.

The pins are retained in the pin receiving means by the retaining means. Thus, it is not necessary that the hollow outer member be provided with pin loading means. The retaining means may comprise an adhesive of low adhesive power, grease or other viscous material, a sheet of material extending over the pins, one or more elastic members, such as rubber bands or any other suitable means for retaining the pins in the pin-receiving means. The retaining means preferably does not permanently mount the pins to the inner member. The retaining means should also not prevent the pins from moving from the retracted position to the extended position.

In a third aspect, the present invention provides a fixation device comprising a hollow outer member having at least one opening, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, at least one region defined between the inner member and the hollow outer member such that at least a part of a pin can fit between the inner member and the hollow outer member wherein a pin positioned in the at least one region slopes in an outward direction relative to a longitudinal axis of the inner member and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement between the hollow outer member and the inner member.

In a most preferred embodiment, the one or more regions are defined at least in part by pin receiving means on the inner member. The pin receiving means on the inner member preferably comprise one of more sloped regions, frusto-conical regions, regions of reduced diameter, slots, grooves, cavities or depressions on the inner member. The pin receiving means are suitably formed on the outer surface of the inner member. The pin receiving means are preferably shaped such that each pin fits into a respective pin receiving means. More preferably, the pin receiving means are of a generally complementary shape to the shape of the pins.

It is especially preferred that the pin receiving means is shaped such that the second end of the pin does not extend above a level of an outermost surface of the inner member and the first end of the pin protrudes just above an outermost surface of the inner member. In this fashion, the first end can come into contact with an edge of a loading means or an opening in the hollow outer member during extension of the pins.

This assists in forcing the pins towards the extended position by continued longitudinal relative movement between the hollow outer member and the inner member. Most suitably, the pin receiving means is shaped such that a second end of the pin is substantially restrained against longitudinal movement when positioned in the pin receiving means whilst allowing for rotation of the pin about the second end.

More preferably, the pin receiving means includes a slot portion formed on the inner member, said slot portion being oriented generally in alignment with a longitudinal axis of the inner member and said slot portion having a bottom that slopes downwardly from a first end to a second end.

Preferably, the pin receiving means is as described with reference to the first aspect of the present invention.

Preferably, the pin receiving means is shaped such that an outermost part of the first end of the pin is positioned outwardly of an outermost part of the second end of the pin when the pin is in the pin receiving means.

The present invention also extends to methods for using the fixation devices in accordance with the first and second aspects of the present invention.

In a fourth aspect, the present invention provides a method for affixing a fixation device in accordance with the first aspect of the invention, the method comprising the steps of inserting the inner member into the hollow outer member, loading at least one pin through the loading means such that the at least one pin is positioned within a receiving means on the inner members, inserting the fixation device into a cavity or space and causing relative longitudinal movement between the inner member and the hollow outer member to thereby extend the at least one pin.

The at least one pin may engage with a wall or walls of the cavity or the space to thereby fix the device within the cavity or space. Alternatively, the at least one pin may enter or be surrounded by a hardenable medium, such as cement, concrete, an adhesive, a resin or the like, such that the device is fixed when the hardenable medium hardens or sets.

The method of use of the fixation device of the second aspect of the invention is generally similar except that the loading step is not required.

In a fifth aspect, the present invention provides a method for affixing a fixation device in accordance with the second aspect of the invention, the method comprising the steps of inserting the inner member into the hollow outer member, inserting the fixation device into a cavity or space and causing relative longitudinal movement between the inner member and the hollow outer member to thereby extend the at least one pin.

Brief description of the drawings

Figure 1 is a side view in cross-section of a fixation device in accordance with the present invention with the pins in an armed but retracted position;

Figure 2 is a side view in cross-section of the device of Figure 1 but with the pins in an extended position;

Figure 3 is a side view in cross section of a device in accordance with the invention positioned within a hole in a medium and the pins in a retracted position;

Figure 4 is a side view in cross-section of the device of Figure 3 but with the pins in an extended position;

Figure 5 is a schematic view of a loading means formed in the hollow elongate member of a fixation device in accordance with the present invention;

Figure 6 is a schematic view of another loading means formed in the hollow outer member of a fixation device in accordance with the present invention;

Figure 7 is a schematic view of a further loading means formed in the hollow outer member of a fixation device in accordance with the present invention;

Figure 8 is a view that is generally similar to Figure 4 but with the pins only partly extended; Figure 9 is a side view in cross section of a further embodiment of the present invention;

Figure 10 is a side view of an inner member for use in another embodiment of the present invention;

Figure 11 is a part-fragmentary side view of a hollow outer member used in conjunction with the inner member of Figure 10, also showing pins in position;

Figure 13 is a side view of a pin for use with the embodiment of Figures 10 and ii;

Figure 13 is a side view of another embodiment of a hollow outer member for use in the present invention; and

Figure 14 is a cross-sectional end view taken along line 14-14 in Figure 13.

Detailed description of the drawings

The attached drawings show preferred embodiments of the present invention. It is to be understood that the present invention should not be construed to be limited solely to the features as shown in the attached drawings.

Figure 1 shows a schematic view, in cross-section, of a fixation device in accordance with one embodiment of the present invention. It will be appreciated that the Figure 1 and Figure 2 may show only part of the fixation device. In particular, the fixation device may be of greater length and have one or more further pins than those shown in Figures 1 and 2. It will also be appreciated that the radius of the device, the length and width of the pins and the shape of the pins may be varied.

The device 10 in accordance with Figure 1 includes a hollow outer member 12. Hollow outer member 12 is in the form of a tube. For ease of convenience, hollow outer member 12 will hereinafter be referred to as outer tube 12.

The device further includes an inner member 14. Inner member 14 is preferably a solid member having a general cylindrical cross-section. Inner member 14 is sized such that it can fit snugly into, but not too tightly into, the outer tube 12. This enables the inner member 14 to be slideably inserted into outer member 12.

The device 10 further includes a plurality of pins. In Figures 1 and 2, two pins 16, 18 are shown. However, it will be appreciated that the number of pins may be varied.

Pin 16 includes a first end 20 and a second end 22. First end 20 is bevelled or sharpened to form a point. Second end 22 is in the form of a bulbous or generally spherical enlargement. The reasons for this will be explained hereunder.

The outer member 12 further includes a plurality of openings 24, 26. Again, it will be appreciated that the number of openings in the outer member 12 may be varied. The openings 24, 26 are suitably in the form of a slot having greater length than width.

Opening 24 may have a first edge 28 that is bevelled such that sharpened end 20 of pin 16 can make contact with bevelled edge 28 to assist and allow for the smooth movement of the pin and to reduce the possibility of the point of the pin penetrating the outer member 12 during extension of the pin.

Similarly, opening 26 may have a bevelled edge 30 for the same reasons.

The inner member 14 is also provided with a plurality of pin receiving means. The pin receiving means of the device shown in Figures 1 and 2 comprises a plurality of grooves or cavities formed in the inner member 14. The pin receiving means for pin 16 comprises a groove 32. As can be seen from Figures 1 and 2, groove 32 is of increasing depth in a direction from the first end 20 of pin 16 to the second end 22 of pin 16. The groove 32 is also provided with a generally spherical enlargement 34. The generally spherical enlargement 34 is sized to receive the second end of pin 16 such that the second end 22 sits below or level with the surface of the inner member 14. Furthermore, the generally spherical enlargement 34 of groove 32 partially encases the second end 22 such that the second end 22 of pin 16 cannot move longitudinally along the inner member.

The pin receiving member, along with the inner wall of the outer member, defines a space that can receive at least part of a pin. Pin 26 is received in a similar pin receiving means. As can be seen from the figures, the pins are generally parallel to the longitudinal axis of the inner member when the pins are in a loaded position.

The groove 32 is also shaped and sized such that first end 20 of pin 16 protrudes just above the surface of the inner member. When the inner member is moved longitudinally to the right (as shown in figure 1) the first end 20 of pin 16 comes into contact with edge 28 of opening 24. Continued movement of the inner member 14 to the right (as shown in figure 1) causes the pins 16, 18 to rotate outwardly about the second end and ends thereof. When the inner member has been moved to a position as shown in figure 2, the shank of pin 16 located adjacent to the second end 22 comes into contact with edge 36 of groove 32. The other side of the shank of pin 22 comes into contact with the bevel edge 28 of opening 24. This effectively locks the pin 16 into the extended position as shown in figure 2. Operation of the other pins is identical to that as described for pin 16.

Although the above description describes movement of inner member 14 to the right, it would be appreciated that any relative longitudinally movement between inner member 14 and outer member 12 can result in the pins being moved from the retracted position shown in figure 1 to the extended position shown in figure 2.

It will be appreciated from the above description that the pins are extended, either partially or fully, by opposing forces that act between the inner and outer members along the line from the second end of the pins towards the first ends of the pins.

If the nails are extended only partially, they form barbs, the angle of which varies depending on the length of the nails and the distance travelled by the inner member relative to the outer member. The amount of extension of the pins depends upon the length of the opening or slot in the outer member. If the length of the opening or slot is short, only a short length of pin is extended before the trailing edge of the pin receiving means on the inner member makes contact with the pin and then jams the pin at this length of extension. To retract the pins, the inner and outer members are longitudinally relatively moved to each other in an opposite direction to the direction when the pins were extended.

Fixation of the device to a medium, such as a wall, member or the like, is shown in figures 3 and 4. In figure 3, the medium, which in this case comprises a solid member

40, has a hole 42 drilled therein. Fixation device 10 is then inserted in the hole 42. The inner member 14 has a threaded portion 44 and a nut 46 is positioned over this threaded portion. As shown in figure 3, the pins 16, 18 of the device 10 are in a retracted position when the device 10 is inserted into hole 42.

In order to move the pins 16, 18 from the retracted position to the extended position, as shown in figure 4, nut 46 is tightened. As nut 46 cannot move past the front edge 48 of the outer tube 12, continued rotation of nut 46 causes inner member 14 to move longitudinally to the right. This then causes extension of pins 16, 18. Furthermore, the threaded portion 44 of inner member 14 is also available for connection of other devices thereto.

Figure 5 shows one method for loading pins into the device. In the embodiment shown in figure 5, outer tube 12 has a pin loading means 50 formed therein. Pin loading means 50 is in the form of an opening in the outer tube 12. The opening has a shape that is generally complementary to the shape of the pin 16 that is inserted through the pin loading means 50. In particular, pin loading means 50 includes a rounded portion 52 that is of similar shape but slightly larger than second end 22 of pin 16. Further, pin loading means 50 includes an elongate slot portion 54 that has a width slightly greater than the diameter of the shank of pin 16. Elongate slot portion 54 is also of greater length than the length of the shank of pin 16.

In one embodiment, the outer tube 12 may be provided with a plurality of pin loading means 50. In this embodiment, the pin loading means 50 may also comprise the openings in the outer tube 12 through which the pins extend when in the extended position. To this end, pin loading means 50 may also be provided with a bevelled edge 28 that engages the sharpened or pointed end 20 of pin 16. Alternatively, the outer tube 12 may be provided with a plurality of other openings (not shown in figure 5). In this embodiment, it is possible for all the pins to be loaded into the device through pin loading means 50. In operation of this embodiment, the inner member is inserted into the outer tube 12 until a first pin receiving means of inner member 14 is positioned under pin loading means 50. A first pin 16 is then inserted through pin loading means 50 such that the pin 16 rests in the pin receiving means positioned thereunder. Other pins are then loaded along the same row similarly. The inner tube may then be rotated or, more preferably moved in the direction of first end 20 of pin 16 until the second end 22 of pin 16 is located under the elongate slot portion 54 of pin loading means 50. In this position, the enlarged second end 22 of pin

16 is positioned under elongate slot portion 54 of pin loading means 50 and thereby prevented from falling out of the pin receiving means. The inner member can then be moved either, preferably by rotation, until a next pin receiving means or row of pin receiving means on the inner member is in alignment with the pin loading means 50. The next row of pins can then be loaded by a similar procedure.

Further pins or row of pins can also be loaded by a similar procedure. This procedure can be continued until the desired numbers of pins or rows of pins that are required radially around the inner member have been loaded.

After the last pin or row of pins has been loaded into the device, the inner member is moved in the direction of the first end 20 of the pins 16 relative to the outer tube 12, until the bevel or sharpened point 20 of the pins is positioned such that it is in contact with the outer tube 12 and resting on the bevelled edge 28 of respective openings in the outer tube. The enlarged second end 22 of each pin is then fixed between the inner member and the outer tube 12. Although this retains the pins in place between the inner member and outer tube 12, the pins are able to be rotated about the enlarged second end

22. The pins are then in the "armed" position as shown in figure 1. Extension of the pins is by a similar procedure as shown in figures 2 or 4.

It will be appreciated that the inner member is provided with a plurality of pin receiving means and that the plurality of pin receiving means are positioned on the inner member such that the loaded pins in the pin receiving means can be aligned with respective openings in the outer tube 12.

Although the embodiment shown in figure 5 does not require any further retaining means to retain the pins in place in the pin receiving means, it is possible to provide such retaining means. The pin retaining means may comprise a fine membrane extending around the outer tube 12 (the membrane may be plastic, fibrous or woven), or a rubber band, or a dab of grease or adhesive of low adhesive power or other viscous material in the pin receiving means.

Figure 6 shows an alternative embodiment of a pin loading means for use in the present invention. In the embodiment shown in figure 6, the pin loading means 60 includes a round portion 62 for receiving the second end 22 of pin 16. The pin loading means 60 also includes an elongate slot portion 64 for receiving the shank and sharpened end 20 of pin 16. The pin loading means 60 is also in communication with opening 66. Opening 66 is an opening through which a pin extends when the pin is in the extended position. As such opening 66 includes a bevelled front edge 68. This opening acts in similar fashion to opening 24 as described in figure 1.

Opening 66 is connected to elongate slot portion 64 by a narrowed portion 70. Narrowed portion 70 is bounded by tabs 72, 74 that form a bridge in the outer tube. Tab 72, 74 act to restrain the second end 22 and the shank or part of the shank of pin 16 when the pin 16 is in the armed position. The narrowed portion 70 is effectively a narrowed slot formed through the bridge which allows the tip of the pin to slide therethrough when the pin is moved into the armed position.

A further alternative pin loading means is shown in figure 7. In figure 7, the pin loading means 80 comprises a round portion 82 and an elongated slot portion 84. A bevelled front edge 86 is provided to engage with the bevelled or sharpened end 20 of pin 16.

In order to retain the pin 16 in place, the pin 16 is loaded through pin loading means 80 and the inner member and outer tube 12 are then relatively rotated such that a pin retaining wing 88 is positioned over the pin, thereby retaining the pin in the pin receiving means in the inner member. As shown in figure 7, the pin retaining wing 88 is positioned over the proximal shank of the pin. However, it will be appreciated that the pin retaining wing 88 may be positioned such that it extends over any suitable part of the pin 16.

Figure 8 is generally similar to figure 4 in that it shows a fixation device in accordance with the present invention fixed into a wall. For convenience, the features of figure 8 have been given a similar reference number to the features of figure 4. The drawing shown in figure 8 shows the pins 16, 18 in a partially extended position. In the partly extended position shown in figure 8, pins 16 and 18 provide barbs that are angled to resist removal of the device 10 from the wall.

Figure 9 shows a further embodiment of the present invention in which a further outer member 90 having suitably sized and positioned slots or openings 92 is positioned over the original outer member 12. Further outer member 90 includes a threaded portion 94 having a nut 96 threadably engaged thereon.

Further outer member 90 is used to provide extra strength to the device of the present invention.

Figures 10, 11 and 12 show another embodiment of the present invention. In figure 10, the inner member 100 has been formed, machined or turned such that includes a number of conical sections 102, 104. The conical sections define, together with the inner wall of the outer member a space in which a pin can sit.

The conical turned sections 102, 104 also have grooves 106, 108 milled therein. The grooves 106, 108, comprise pin receiving grooves. A milled, concaved depression 110, 112 are also formed in the respective grooves 106, 108.

The hollow outer member 116 includes at least one loading opening 118. The loading opening 118 includes a head receiving opening 120 which receives the enlarged head 122 of pin 124 (see figure 12). The pin head opening 120 is positioned to the side of loading slot 126. The gap 128 between pin head opening 120 and loading slot 126 is sized such that the enlarged pin head 122 can fit through pin head opening 120. The outer tube can then be rotated such that the shank 130 of the pin 124 passes through gap 128. The pin 124 can then be loaded by rotating the pin until the shank 130 is in alignment with slot 126. The inner member can then be pushed to the left (as shown in figure 11) until the pin 124 is in the position as shown in dotted outline in figure 11.

Figure 11 also shows another pin 132 which has been properly positioned in the device. As can be seen, the first end 134 of the pin 132 extends through an opening 136 formed in the wall of the hollow outer member 116.

In order to extend the pins of the apparatus shown in figures 10 to 12, the inner member is moved relatively to the right (as shown in figure 11). This causes end 134 of pin 132 to contact wall 138 of opening 136 in the hollow outer member 116. As a result, pin 132 is pushed upwardly and outwardly. As continued movement of the inner member to the right occurs, the pin 132 moves to a further extended position. Figures 13 and 14 show another embodiment of an alternative hollow outer member that may be used in the present invention. In figures 13 and 14, the hollow outer member 140 includes a plurality of pin loading means 142, 144. Pin loading means 142 includes an enlarged pin head opening 146 and a longitudinal slot 148. A further transversely extending slot 150 connects pin head opening 146 to slot 148.

Pin loading means 144 is essentially the same. As best shown in figure 14, the hollow elongate member 140 has three pin loading means 142, 152, 154 formed in a "row" around peripheral portions of the hollow elongate member.

In use of the apparatus shown in figure 9, when the nails are extended to their desired position, the new outer member can be adjusted by tightening nut 96 until the trailing edge of the slots 92, contact the shank of the pins 16, 18.

Preferred embodiments of the apparatus of the present invention provide a fixing device that does not require extensive pre-assembly. The fixing pins can be easily loaded into the device on site. Complex assembly of pins being permanently mounted for rotation to the inner member is not required. Moreover, the end user of the fastening device can make decisions as to the number of pins required for any particular fastening application. Those skilled in the art will appreciate that the invention described herein may be susceptible to variations and modifications other than those specifically described. It is to be understood that the present invention encompasses all such variations and modifications that fall within its spirit and scope.

Claims

1. A fixation device comprising a hollow outer member, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, at least one region defined between the inner member and the hollow outer member such that at least a part of a pin can fit between the inner member and the hollow outer member, loading means in the hollow outer member for loading the at least one pin, and wherein a pin is loaded by entering the pin into the loading means such that the pin is received in an at least one region and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement of the imier member and the hollow outer member.

2. A fixation device as claimed in claim 1 wherein the at least one region defined between the inner member and the hollow outer member that allows at least a part of a pin to fit between the inner member and the hollow outer member includes one or more portions on the inner member that, together with an inner wall of the hollow outer member, define the at least one region.

3. A fixation device as claimed in claim 2 wherein the inner member includes one or more pin receiving means that, together with the hollow outer member, define the one or more regions.

4. A fixation device as claimed in claim 3 wherein the pin receiving means include sloped region(s), frusto-conical region(s), region(s) of reduced diameter, slot(s), groove(s), cavities or depressions

5. A fixation device as claimed in claim 1 wherein the at least one region is defined by one or more portions on the hollow outer member that, together with the inner member, define the one or more regions.

6. A fixation device as claimed in claim 1 wherein both the inner member and the hollow outer member include one or more portions that together define the one or more regions.

7. A fixation device as claimed in any one of claims 1 to 6 wherein the at least one region restrains an end of the pin against movement in one longitudinal direction when a pin is positioned in the region.

8. A fixation device as claimed in claim 2 wherein the pin receiving means are shaped such that the second end of the pin does not extend above a level of an outermost surface of the inner member and the first end of the pin protrudes just above an outermost surface of the inner member, such that the first end of the pin comes into contact with an edge of a loading means or an opening in the hollow outer member during extension of the pins

9. A fixation device as claimed in claim 8 wherein the pin receiving means are shaped such that a second end of the pin is substantially restrained against longitudinal movement when positioned in the pin receiving means whilst allowing for rotation of the pin about the second end.

10. A fixation device as claimed in claim 2 including a plurality of pin receiving means.

11. A fixation device as claimed in any one of the preceding claims wherein the pin extends through the loading means when in the extended position.

12. A fixation device as claimed in any one of claims 1 to 10 wherein the hollow outer member includes at least one opening and the pin or pins extend tlirough associated ones of the at least one opening when in the extended position.

13. A fixation device as claimed in any one of the preceding claims including a plurality of pins.

14. A fixation device as claimed in claim 13 further including a plurality of loading means or a plurality of openings in the hollow outer member or both and wherein the inner member includes a plurality of pin receiving means.

15. A fixation device as claimed in any one of the preceding claims wherein the pin loading means includes at least one opening in the side wall of the hollow outer member.

16. A fixation device as claimed in claim 15 wherein the pin loading means is shaped such that it is of generally complementary shape to a cross-sectional shape of a pin.

17. A fixation device as claimed in claim 1 wherein the pin loading means is in communication with an opening through which the pin extends when in the extended position and the hollow outer member is provided with pin retaining means for retaining the pin when it is positioned such that a second end of the pin is not in alignment with the pin loading means.

18. A fixation device as claimed in claim 17 wherein the pin retaining means comprises a bridge, flange, wing or other suitable shape formed in the hollow outer member.

19. A fixation device as claimed in claim 1 wherein the loading means includes an opening through which an enlarged end of a pin can pass, the loading means further including a part through which a shank portion of the pin can pass but which is smaller than the enlarged end of the pin.

20. A fixation device as claimed in claim 19 wherein the loading means further includes a longitudinal slot and the opening through which the enlarged end of the pin can pass is positioned an end of the longitudinal slot or to or at a side of the longitudinal slot.

21. A fixation device comprising a hollow outer member having at least one hole in a side wall thereof, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, the inner member having at least one pin receiving means for receiving a pin and retaining means for retaining the at least one pin in said pin receiving means, wherein in use the inner member has the at least one pin positioned in respective ones of the at least one pin receiving means and the at least one pin is retained in place by the retaining means, and the inner member is thereafter inserted into the hollow outer member and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement of the inner member and the hollow outer member.

22. A fixation device as claimed in claim 21 wherein the retaining means comprises an adhesive of low adhesive power, grease or other viscous material, a sheet of material extending over the pins, one or more elastic members

23. A fixation device as claimed in claim 21 or claim 22 wherein the retaining means does not permanently mount the pins to the inner member.

24. A fixation device comprising a hollow outer member having at least one opening, an inner member sized to be slideably received within the hollow outer member, at least one pin having a first end and a second end, at least one region defined between the inner member and the hollow outer member such that at least a part of a pin can fit between the inner member and the hollow outer member wherein a pin positioned in the at least one region slopes in an outward direction relative to a longitudinal axis of the inner member and wherein the at least one pin is moved from a retracted position to an extended position by relative longitudinal movement between the hollow outer member and the inner member.

25. A fixation device as claimed in claim 24 wherein the pin receiving means is shaped such that the second end of the pin does not extend above a level of an outermost surface of the inner member and the first end of the pin protrudes just above an outermost surface of the inner member such that the first end comes into contact with an edge of a loading means or an opening in the hollow outer member during extension of the pins.

26. A fixation device as claimed in claim 24 or claim 25 wherein the pin receiving means is shaped such that a second end of the pin is substantially restrained against longitudinal movement when positioned in the pin receiving means whilst allowing for rotation of the pin about the second end.

27. A method for affixing a fixation device according to any one of claims 1 to 20 or 24 to 26, the method comprising the steps of inserting the inner member into the hollow outer member, loading at least one pin through the loading means such that the at least one pin is positioned within a receiving means on the inner members, inserting the fixation device into a cavity or space and causing relative longitudinal movement between the inner member and the hollow outer member to thereby extend the at least one pin.

28. A method for affixing a fixation device according to any one of claims 21 to 23, the method comprising the steps of inserting the inner member into the hollow outer member, inserting the fixation device into a cavity or space and causing relative longitudinal movement between the inner member and the hollow outer member to thereby extend the at least one pin.