Orthopaedic implant

An orthopaedic implant, namely a locking device for anchoring to cortical bone for the fixation of fractures of bone and/or dislocations of joints. The locking device includes a cable, a locking member slidable over the cable, and a spreader member attached to a distal end of the cable. The locking member has an expandable portion that may be expanded when the locking member engages the spreader member. A capturing assembly has a raised portion and a contractible passage therethrough for securably receiving a proximal portion of the cable, and preferably includes a cooperating sleeve and annular-shaped member adapted to contract the contractible passage. The cable and locking device are introduced through a hole in a bone, the locking member is expanded, thereby engaging the distal or far surface of the bone. The capturing assembly is introduced over the cable until the raised portion engages the proximal or near surface of the bone. Tension is applied to the cable, and the annular-shaped member is directed into the sleeve, thereby contracting the contractible passage and securing the cable therein.

FIELD OF THE INVENTION 
The present invention relates generally to orthopaedic surgical devices, 
and more particularly to a device for securing bone segments against one 
another, such as for fixing bone fractures and joint dislocations. 
BACKGROUND OF THE INVENTION 
Various types of orthopaedic devices have been described for the fixation 
of bone fragments. Such devices are often used to stabilize bones, thereby 
enhancing the healing of fractures and/or promoting union of joints being 
fused together. This stability helps allow early return of the function of 
the body part and improves patient well being. 
For example, bone screws are commonly used devices for fixing bone 
fragments. The bone fragments are positioned in their proper 
configuration, and one or more holes are then drilled and tapped across 
the fracture. The screws are then screwed into the holes, thereby 
compressing the bone fragments, for example, by using a lag screw 
technique of over-drilling a gliding hole in the near side (cortex) of the 
bone. In addition, bone screws are often used in conjunction with metal 
plates to increase stability against multiplanar forces which may act upon 
the bone fragments. The screws are placed through holes in the plates, 
thereby lagging the plate against the bone in compression. 
Metal pins (e.g. Kirschner wires and Steinman pins) are also often used to 
stabilize bones. The pins may be threaded or smooth, and are drilled 
across bone fragments to provide stability to the bone. Pins may also be 
used together with external fixators to gain purchase of bone fragments. 
These devices include an external rigid framework that lies outside of the 
body. Pins are inserted through the framework and into the body, by 
piercing the skin and inserting the pins into drilled, tapped holes in the 
bone. 
Intrameduallary implants are another conventional device used, especially 
for long, tubular bone fragments. These nail-like devices are placed in 
the central canal of a bone to gain an interference fit and/or are locked 
at the ends by screws to secure the bone fragments in place. Such implants 
act as an internal splint within the bone, and allow compression of the 
bone piece during weight bearing. 
Cables are also used to hold bone pieces together, for example by wrapping 
a cable around long, thin pieces of bone and then tensioning the cable, 
the bone fragments may be held together. The cables are typically held by 
a metal crimping piece that maintains the tension of the cable. Wrapping 
the cable around bone pieces in a cerlage technique is limited, however, 
and is generally used only to fix cracks in only one cortex of a tubular 
bone, or to link long slabs of bone (known as cortical struts) onto the 
outer surface of a tubular bone. In particular, very oblique or long 
spiral fractures in long tubular bones may be secured by cables to hold 
the bone in a stable state of compression. 
Other bone anchors have been used primarily to attach suture materials to 
bone so that the suture may be secured to soft tissue, such as a ligament 
or tendon, thereby tightly linking the tissue to the bone. These devices 
typically anchor themselves in a hole drilled into the bone, thus 
preventing the device from pulling away from the bone as tension is 
applied to the attached soft tissue structure. 
These conventional bone fixation devices generally gain their purchase to 
the bone by engaging the interior of the bone, i.e., the cancellous bone 
material. Cancellous bone is soft and spongy in nature and consequently 
has inferior holding power as compared with the exterior portion of the 
bone, i.e. cortical bone. The tension imposed on the devices after 
implantation may exceed the stresses that the bone-implant interface is 
able to resist, and may result in implant failure. Such devices may also 
require extensive surgical exposure of the bones to allow implantation of 
the devices, which may result in increased risk of infection and/or 
increased pain in the patient. 
In contrast, external fixator devices may not require extensive surgical 
exposure, because they merely violate the skin with pins. However, use of 
such devices may be complicated by infection in and around the pin tracts 
beneath the skin. These external devices may also reduce patient comfort 
as compared to internally implanted devices. 
Finally, although cable devices provide excellent tensionresistance, their 
use is generally limited because of the limited methods of attaching the 
cable to bone. 
Accordingly, there is a need for an improved orthopaedic implant device 
that provides increased bone purchase and/or may be implanted with minimal 
surgical exposure. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, an orthopaedic implant or locking 
device is disclosed for compressibly securing a hard tissue structure, 
such as a bone having a fracture therein. The locking device includes an 
elongate member, preferably a cable or metal rod, having proximal and 
distal ends, and having a proximal portion. 
A locking member is slidably received over the cable, and has a radially 
expandable portion capable of being expanded between contracted and 
enlarged conditions, and preferably comprising a plurality of flanges 
disposed radially about the locking member. The radially expandable 
portion includes a proximal surface for engaging a far or distal surface 
of the bone. 
A retaining or spreader member is attached or integrally formed on the 
distal end of the cable. The spreader member is adapted to be slidably 
engaged by the locking member to prevent the locking member from sliding 
distally off the cable. Preferably, the spreader member has a tapered 
portion extending proximally from the distal end of the cable, more 
preferably having a frustoconical shape, for expanding the radially 
expandable portion of the locking member. 
The locking device also includes a capturing assembly having a contractible 
passage therein for securably receiving the proximal portion of the cable 
therethrough. The capturing assembly includes a raised portion, preferably 
an annular flange, having a distal surface for engaging the near or 
proximal surface of the bone being stabilized by the device. 
Preferably, the capturing assembly includes a capturing sleeve having the 
raised portion extending radially about the sleeve, and having an aperture 
therein at least partially defined by a flange. The flange also partially 
defines the contractible passage extending through the capturing sleeve. 
In addition, the capturing assembly preferably also includes an 
annular-shaped threaded member adapted to be rotatably received within the 
aperture in the capturing sleeve. As the threaded member is screwed into 
the aperture, it forces the flange radially inward, thereby contracting 
the contractible passage to secure the cable inserted therethrough. 
To implant the locking device in accordance with the present invention, a 
bone is positioned in a desired configuration, and a hole is drilled from 
a proximal portion to a distal portion of the bone, preferably from the 
anterior surface to the posterior surface thereof, for example across a 
fracture being stabilized therein. The distal end of the cable with the 
locking member thereon is introduced into the hole until it is at least 
partially exposed beyond the far or distal surface of the bone. 
The radially expandable portion of the locking member is expanded to its 
enlarged condition, thereby having a cross-section substantially larger 
than the hole, and being able to substantially engage the far or distal 
surface of the bone and prevent the distal end of the cable from moving 
proximally. The capturing assembly is then directed over the proximal end 
of the cable until it engages the near or proximal surface of the bone. 
A predetermined tension is applied to the proximal end of the cable, and 
the capturing assembly is contracted to secure the cable therein. For 
example, the threaded member may be screwed or otherwise directed into the 
capturing sleeve, thereby forcing the flange on the capturing sleeve to 
contract the contractible passage and substantially secure the cable 
therein. The tension is then released from the proximal end of the cable, 
thereby compressing the bone between the proximal and distal portions 
thereof and consequently securing the fracture therein. In this 
embodiment, the cable may be substituted by a metal rod serving a similar 
although more rigid function of maintaining tension between the distal 
locking member of the proximal capturing assembly. 
In a second preferred embodiment, the locking device includes a pair of 
cables, each having a spreader member and a locking member thereon. The 
cables are preferably used to stabilize two separate bone fragments 
disposed adjacent one another. A hole is drilled into each bone, each 
cable is introduced into the respective hole, and each locking members is 
expanded to engage the far or distal surface of the respective bone. A 
centering sleeve having a raised portion thereon is then directed over 
each cable until it abuts the near or proximal surface of each bone 
fragment. 
A crimper member is then provided having a pair of passages therein for 
receiving the cables therethrough. A predetermined tension may be applied 
to each cable, and then the crimper member may be crushed or compressed, 
thereby securing the cables therein. 
Orthopaedic implant devices in accordance with the present invention 
provide a compressive locking device for stabilizing a bone structure 
having a fracture therein or being fused after a joint dislocation. The 
compressive forces imposed by the locking device are applied to the outer 
surfaces of the bone structure, that is, cortical bone rather than 
cancellous bone. Thus, the locking device may provide substantially 
greater stress resistance than devices which screw into soft cancellous 
bone. Further, a locking device in accordance with the present invention 
may require only a limited surgical exposure, thereby enhancing patient 
comfort and minimizing risk of infection. 
Thus, it is an object of the present invention to provide an improved 
orthopaedic implant for securely fixing bone segments together, thereby 
facilitating healing and comfort of the patient. 
Additional objects and features of the present invention will become 
apparent from consideration of the following description taken in 
conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Turning to FIGS. 1-3, SA and SB, a preferred embodiment of an orthopaedic 
implant device in accordance with the present invention is shown, namely a 
locking device 10. The locking device 10 includes a cable 20, a spreader 
member 30, a locking member 40, and a capturing assembly 60. The cable 20 
comprises an inelastic elongate member having a distal end 22 and a 
proximal end 24. The spreader member 30 is a retaining member that is 
substantially permanently attached to the distal end 22 of the cable 20. 
Preferably, the spreader member 30 includes a passage 32 into which the 
distal end 22 of the cable 20 is inserted and affixed, for example, by 
adhesives, welding, crimping and the like. Alternatively, the spreader 
member 30 may be integrally formed on the cable 20 or may abut and extend 
distally from the distal end 22. 
The spreader member 30 includes a distal base 36 and tapers towards the 
proximal end 24 of cable 20, providing a tapered proximal surface 34 for 
engaging the locking member 40. Preferably, the spreader member 30 has a 
conical or frustoconical shape that tapers proximally from the distal end 
22 of the cable 20 along a portion thereof. Alternatively, the spreader 
member 30 may include other configurations or segments, for example, one 
or more radially extending flanges or tabs to prevent the locking member 
40 from sliding distally off of the cable 20 and/or a ramped proximal 
portion for expanding the locking member 40. 
The locking member 40 comprises a substantially cylindrical member having a 
passage 48 (FIG. 3) extending axially therethrough, and having an 
expandable portion 43 capable of being radially expanded from an initial 
contracted condition to an enlarged condition. Preferably, the locking 
member 40 includes a cylindrical sleeve 42 having a plurality of flanges 
or fins 44 extending radially therefrom. More preferably, the locking 
member 40 has four fins 44 integrally formed thereon having a proximal 
surface 50, and together defining a substantially annular shape. The fins 
44 are separated by notches or gaps 46 therebetween, which extend 
proximally along a portion of the sleeve 42 and extend radially through to 
the passage 48 (FIG. 3), thereby allowing the fins 44 to be expanded 
radially. 
The locking member 40 is slidably received over the cable 20 by orienting 
the fins 44 towards the spreader member 30, inserting the proximal end 24 
of the cable 20 into the passage 48, and directing the locking member 40 
distally. Generally, the passage 48 has a diameter substantially smaller 
than the base 36 of the spreader member 30, and preferably only slightly 
larger than the diameter of the cable 20. The spreader member 30 thereby 
substantially retains the locking member 40 on the cable 20. More 
preferably, the diameter of the passage 48 is only slightly larger than 
the diameter of the proximal end 35 of the spreader member 30. The cable 
20 may be directed proximally in relation to the locking member 40, 
thereby forcing the inner surface 45 of the fins 44 to engage the tapered 
proximal surface 34 of the spreader member 30 and expanding the fins 44 
radially outward as the spreader member 30 partially enters the passage 
48. 
The bone fixation device 10 (in FIG. 1) also includes a capturing assembly 
60 for receiving the proximal end 24 of the cable 20 therethrough, and 
preferably for securing a proximal portion thereof. Preferably, the 
capturing assembly 60 includes a cooperating capturing sleeve 62 and 
threaded member 80. The capturing sleeve 62 has a substantially 
cylindrical portion 64 having a contractible cable passage 66 extending 
axially therethrough. The cable passage 66 preferably has an initial 
diameter slightly larger than the diameter of the cable 20, thereby 
allowing the cable 20 to be directed therethrough. The capturing sleeve 62 
also has a raised portion 68 extending radially from an outer surface 65 
of the cylindrical portion 64. Preferably, the raised portion 68 is an 
annular shaped flange integrally formed around the cylindrical portion 64, 
and including a distal or abutting surface 70. 
Extending partially into the proximal end 72 of the cylindrical portion 64, 
is a substantially annular-shaped aperture 74 for receiving the threaded 
member 80 therein. The aperture 74 preferably has a threaded outer wall 76 
and a substantially smooth inner wall 77, and has a gradually tapering 
cross-section as it extends distally into the cylindrical portion 64. The 
capturing sleeve 62 thus includes an annular-shaped flange 78 between the 
cable passage 66 and the aperture 74. Alternatively, the cylindrical 
portion 64 may include one or more flanges 78 disposed radially about the 
cable passage 66 and separated by slots or gaps (not shown) extending 
radially between the cable passage 64 and the aperture 74. 
The threaded member 80 has a substantially annular crosssection similar to 
the aperture 74, although preferably slightly larger in cross-section than 
the aperture 74, and preferably has a threaded outer wall 82 and a 
substantially smooth inner wall 83 adapted to engage respectively the 
outer wall 76 and inner wall 77 of the capturing sleeve 62. The threaded 
member 80 preferably includes a hexagonal recess 86 in the proximal end 84 
thereof for receiving a hexagonal nut driver (not shown), although 
alternatively, any suitable geometric recess or protrusion (not 5 shown) 
may be provided on the proximal end 84 for cooperating with a tool (not 
shown) to rotate the threaded member 80 in relation to the capturing 
sleeve 62. Thus, the threaded member 80 may be rotated about its 
longitudinal axis, thereby directing the threaded member 80 axially in 
relation to the capturing 10 sleeve 62 as the threaded walls 76 and 82 
rotatably engage one another. 
Preferably, the inner walls 77 and 83 are inclined as shown, such that they 
slidably engage one another as the threaded member 80 is rotated. Thus, as 
the threaded member 80 is directed 15 distally into the aperture 74, the 
flange 78 is forced radially inward, thereby contracting the cable passage 
66. As should be appreciated by those skilled in the art, the capturing 
assembly 60 may include other socket or collect arrangements for reducing 
or contracting the diameter of the cable passage 66 to secure and 20 lock 
the cable 20 therein. 
With particular reference to FIGS. 3, 5A and 5B, the locking device 10 may 
be implanted to fix bone fragments, preferably using the following steps. 
A bone 90 having a fracture 92 extending therethrough is positioned, such 
that the fragments 90a, 90b are oriented in a desired position for 
fixation. A hole 94 is drilled through the bone 90, preferably 
substantially perpendicular to the fracture 92, and/or substantially 
perpendicular to the outer surfaces of the bone 90, for example from an 
anterior surface 96 of the bone 90. The hole 94 preferably has a diameter 
slightly larger than the diameters of the fins 44 in their contracted 
condition and of the cylindrical portion 64, thereby allowing the bone 
fixation device 10 to be introduced therethrough (see FIG. 5A). 
The distal end 22 of the cable 20, and the locking member 40 with the fins 
44 in their contracted condition, are inserted into the hole 94 from the 
proximal or anterior surface 96, and directed distally until they 
partially emerge from the distal or posterior surface 98 of the bone 90. 
The fins 44 are expanded into their enlarged condition by tensioning the 
cable 20, that is, by directing the cable 20 proximally in relation to the 
locking member 40, causing the inner surface 45 of the fins 44 to engage 
the proximal surface 34 of the spreader member 30, and thereby forcing the 
fins 44 radially outward as the spreader member 30 partially enters the 
passage 48 within the locking member 40 (see FIG. 5B). With the fins 44 
expanded, the proximal surface 50 of the locking member 40 may then abut 
or engage the posterior surface 98 of the bone 90. 
The capturing assembly 60 may then be directed over the cable 20 to abut or 
engage the anterior surface 96 of the bone 90 adjacent the hole 94. 
Preferably, the proximal end 24 of the cable 20 is inserted through the 
cable passage 66 of the capturing sleeve 62, and the cylindrical portion 
64 is directed into the hole 94 until the distal surface 70 of the 
capturing sleeve 62 substantially engages the anterior surface 96. The 
threaded member 80 is then directed over the cable 20 and into the 
aperture 74, or alternatively, may be loosely attached to the capturing 
sleeve 62 prior to introducing the capturing sleeve 62 over the cable 20. 
While maintaining a predetermined tension on the proximal end 24 of the 
cable 20, the threaded member 80 is rotated, directing it distally into 
the aperture 74, thereby forcing the flange 78 radially inward and 
deformationally and/or frictionally engaging the cable 20. The tension may 
then be released from the proximal end 24 of the cable 20, thereby 
subjecting the bone fragments 90a, 90b to compressive forces as the cable 
20 tends to pull the locking member 40 and the capturing sleeve 62 toward 
one another. 
An important feature of the bone fixation device 10 in accordance with the 
present invention is that the compressive forces imposed by the cable 20 
cause the proximal surface 50 of the locking member 40 and the distal 
surface 70 of the capturing member 62 to respectively engage the posterior 
surface 98 and the anterior surface 96 of the bone 90. These surfaces 96, 
98 comprise cortical bone 99 which is substantially stronger than the 
cancellous bone 100 therebetween, and consequently the bone fixation 
device 10 provides improved fixation with substantially reduced likelihood 
of failure as compared to conventional implantation devices which rely on 
contact with cancellous bone 100 to fix the fragments 90a, 90b in their 
proper position. 
In an alternative embodiment, an elongate substantially rigid rod (not 
shown) may be provided instead of the cable, the rod having threads 
extending at least partially along a proximal portion thereof. A retaining 
or spreader member may be provided on its distal end, and a locking member 
may be directed over the rod. The rod may be inserted into a hole drilled 
through a bone structure, as described above, whereupon the locking member 
may be directed distally to expand the fins into their enlarged condition 
as they engage the spreader member. A threaded member may then be screwed 
onto the proximal end of the rod, the threaded member having a raised 
portion to engage the anterior surface of the bone being stabilized. As 
the threaded member is tightened, the bone is substantially compressed 
between the fins on the locking member and the raised portion on the 
threaded member, thereby providing fixation of the fragments therebetween. 
In a further alternative, the fins on the locking member may include 
substantially sharp or pointed edges and/or may be angled or curved in a 
proximal direction. The locking device may then be used to fix bone 
fragments without drilling completely through the bone being stabilized. A 
hole may be drilled across a fracture, the hole not extending completely 
through to the distal or far surface of the bone. The locking device may 
then be inserted into the hole to a predetermined depth beyond the 
location of the fracture being secured. The fins may be expanded similar 
to the method described above. However, instead of expanding to abut the 
posterior surface, the fins may engage or penetrate into the cancellous 
bone, thereby substantially anchoring the locking member in place. 
A capturing assembly similar to that described above may then be directed 
onto the cable, the cable may be subjected to a predetermined tension, and 
the capturing assembly may be tightened to secure the cable therein. Thus, 
the bone may be held in compression between the fins engaging the 
cancellous bone within the hole and the capturing assembly engaging the 
anterior surface of the bone, thereby providing fixation of the fragments 
without penetrating the posterior surface of the bone. 
In another alternative embodiment, the fins on the locking member and the 
raised portion on the capturing member may be provided in orientations not 
substantially perpendicular to the longitudinal axis of the cable, that 
is, the fins and/or the raised portion may define a plane that is not 
substantially perpendicular to the longitudinal axis of the cable. Such an 
embodiment may be useful for stabilizing bones when a hole is drilled 
through the bone that is not substantially perpendicular to the anterior 
and/or posterior surfaces of the bone, that is, the hole defines a 
predetermined angle with one or both surfaces. A locking device having 
fins and/or a raised portion defining a plane substantially matching the 
predetermined angle may be selected for implantation. Thus, when the 
locking device is implanted through the hole, the fins and/or raised 
portion may provide substantially improved engagement with the respective 
surfaces of the bone being stabilized. 
Turning now to FIG. 4, a second preferred embodiment of a locking device 
210 is shown. The locking device 210 includes a pair of cables 220, 
spreader members 230, and locking members 240 similar to those described 
previously. The device 210 also includes a pair of centering sleeves 260. 
Each centering sleeve 260 includes a substantially cylindrical portion 264 
having a cable passage 266 extending axially therethrough, the cable 
passage 266 having a diameter slightly larger than the diameter of the 
cable 220. The centering sleeve 260 also has a raised or abutting portion 
268 extending radially from the cylindrical portion 264. Preferably, the 
raised portion 268 is annular shaped, is integrally formed around the 
cylindrical portion 264, and includes a distal surface 270. 
In addition, the device 210 includes a crimper member 280, preferably 
formed from a substantially malleable metal or similar material. The 
crimper member 280 includes a pair of passages 282 extending therethrough, 
preferably being substantially parallel to one another and having initial 
diameters slightly larger than the diameters of the cables 220. Further, 
the crimper member 280 preferably has a substantially rectangular shape, 
and preferably includes recessed or weakened regions 284, adjacent the 
passages 282. 
The locking device 210 is preferably used when two cables 220 are needed to 
stabilize separate bone fragments 290 with a fracture or to secure a 
dislocation between bone structures that requires fixation. For example, 
the locking device 210 may be particularly useful for stabilizing a 
displaced symphysis pubis. 
Similar to the preferred embodiment described above, each cable 220 and 
locking member 240 is inserted into a respective hole 294 drilled into 
each bone 290, and the fins 44 are expanded to engage the respective 
posterior surface 298. A centering sleeve 260 is then directed over each 
cable 220 until they substantially engage the respective anterior surface 
296, thereby preventing the cables 220 from abrading or otherwise damaging 
the bone adjacent the holes 294. 
The cables 220 are then drawn through the holes 282 in the crimping member 
280, preferably in opposite directions, as shown in FIG. 4, to 
substantially center the crimper member 280 and to transmit evenly the 
forces of the tensioned cables 220. The cables 220 are then tensioned by 
pulling them in opposite directions by a cable gripping tool (not shown. 
This opposes the bone fragments 290. Once a predetermined tension is 
applied to the cables 220, the crimper member 280 is compressed or 
crushed, preferably by crimping across the weakened regions 284, thereby 
securing the cables 220 within the crimper member 280, and stabilizing the 
bones 290. 
The various components of the locking devices described herein may be 
provided from a variety of conventional materials suitable for surgical 
implants. For example, the cable or other elongate member may be 
fabricated from high strength metal alloys, such as 316L stainless steel, 
cobalt/chromium/molybdenum alloy, or Ti6AL4V alloy. The spreader member 
may be formed from metal, plastic or other suitable materials, and 
preferably 316L stainless steel, cobalt/chromium/molybdenum alloy, or 
Ti6AL4V alloy suitable to be substantially permanently attached to the 
cable, that allow the locking member to slide partially over the spreader 
member to expand the fins, and that have substantial strength to retain 
the locking member. The locking member may be formed from a substantially 
rigid material, such as 316L stainless steel, cobalt/chromium/molybdenum 
alloy, or Ti6AL4V alloy that may deform to expand the fins, yet 
substantially maintain its rigidity once the locking device is implanted 
within a bone structure. For example, the fins may include a notch or 
weakened region at their base to facilitate their expansion, yet be 
provided from a substantially rigid material capable of withstanding 
substantial tensile forces, preferably 316L stainless steel, 
cobalt/chromium/molybdenum alloy, or Ti6AL4V alloy. Similarly, the 
capturing assembly components (i.e., the capturing sleeve, the threaded 
member, and the centering sleeve) may be formed from suitable metals, such 
as 316L stainless steel, cobalt/chromium/molybdenum alloy, or Ti6AL4V 
alloy. The crimper member preferably comprises a malleable metal, such as 
316L stainless steel, cobalt/chromium/molybdenum alloy, or Ti6AL4V alloy. 
Other biologic polymers and biometals are on the forefront of development 
and could conceivably replace the above materials as suitable 
alternatives. 
Another aspect of the present invention includes a number of tools that may 
be provided to assist in the implantation process. For example, as shown 
in FIG. 6, an expanding tool 110 may be provided to expand the fins 44 of 
the locking member 40 from their contracted condition to their enlarged 
condition (see FIGS. 5A and 5B). The tool 110 comprises an elongate 
tubular member 112, a handle 114, and a tensioning device 116. The tubular 
member 112 preferably has a passage 118 extending therethrough for 
receiving the cable 20, and may include protrusions, gripping fingers, or 
a similar mechanism (not shown) on its distal end 120 for holding the 
locking member 40 during introduction and expansion. 
The proximal end 122 of the tubular member 112 is integrally formed on or 
attached to the handle 114, which provides a frame for supporting the 
tensioning device 116, and has a chamber 123 therein for receiving the 
cable 20 therethrough. The tensioning device 116 includespartially within 
saidember 124 at least partially within said chamber 123, and a trigger 
126. The gripping member 124 mechanically and/or frictionally holds the 
cable 20 that is received through the tubular member 112 and/or applies a 
proximal, i.e. tensile force to the cable 20. With each pull of the 
trigger 126, the cable 20 is pulled a predetermined distance proximally 
and/or is subjected to an additional tensile force, the gripping member 
124 maintaining the tension applied to the cable 20, as will be 
appreciated by those skilled in the art. 
To use the tool 110, a locking device 10 is attached to the distal end 120 
by inserting the proximal end 24 of the cable 20 through the tubular 
member 112 and into close continuity with the gripping member 116. The 
cable 20 may then be drawn proximally by pulling the proximal end 24 
through the tubular member 112 until the locking member 40 abuts the 
distal end 120 of the tubular member 112 but does not expand the locking 
member 40. 
The distal end 120 of the tool 110 with the locking device thereon is 
introduced into a hole 94 drilled through the bone structure 90 being 
stabilized. The tubular member 112 may include length graduations (not 
shown) extending from its distal end 120 for assisting a surgeon 
performing the implantation to insert the locking device 10 completely 
through the hole 94 to the posterior side 98 of the bone 90 (or optionally 
a predetermined distance past a fracture being secured). The trigger 126 
may then be pulled as many times as appropriate to draw the cable 20 
proximally. As the cable 20 is pulled, the spreader member 30 engages the 
fins 44, expanding the fins 44 radially outward as the spreader member 30 
partially enters a passage 31 within the locking member 40. Once the fins 
44 are fully expanded to their enlarged condition, the gripping member 124 
may be released by releasing the handle 126, and the cable 20 removed from 
the tool 110. 
Turning to FIG, 7, a tightening or locking tool 130 in accordance with the 
present invention may then be utilized to attach the capturing assembly 60 
and complete the implantation of the locking device 10. The tool 130 
includes a cable gripper member 140 and a rotating driver 150 attached to 
a frame or body 132, preferably disposed along a longitudinal axis 133 of 
the body 132, possibly including a handle or support structure (not 
shown). The distal end 134 of the tool 130 has longitudinal splines 136 
for detachably receiving the proximal end 84 of the capturing sleeve 62, 
preferably preventing undesired rotational movement thereof. 
Alternatively, the distal end 134 may include a plurality of gripping 
prongs, or similar mechanical gripping mechanism (not shown). 
The cable gripping member 140 allows mechanical security of the cable to 
longitudinal forces in the axis of the cable 133 by securing the cable 
against a roughened platform 144. The cable gripper member 140 and the 
platform member 144 are linked to a trolley mechanism 151. The trolley 
mechanism 151 is mounted to the frame or body 132 via wheels 133 which 
roll the framework and by gliding antirotational plates 147 which prevent 
rotation of the trolley mechanism 151 during rotation of the rotating 
driver 150. The cable gripper 140 includes a handle 146 for loosening the 
traction on the cable 20 following tensioning. It also comprises a cam 
shaped metallic element 142 with roughened boarder for direct gripping of 
the cable 20 and is set in such a way that pulling on the cable 20 from 
the proximal end 24 by the trolley mechanism 151 only further tightens the 
mechanical interference against the cable 20. The rotational driver 150 is 
comprised of a treaded member for rotationally engaging a fixed threaded 
bolt member 156. It further contains a crank handle 154 for manually 
rotating the rotational driver 150. The rotational driver 150 is linked to 
the trolley mechanism 151 via a rotatable linkage (not shown) which allows 
the rotational driver 150 to apply axial traction to the trolley mechanism 
151 in the axis 133 of the cable 20 while not causing a significant 
rotational moment on the trolley mechanism 151 being stabilized by the 
gliding antirotational plates 147. 
The tightening tool 130 also is to be utilized with a cannulated hexagonal 
nut driver 160. This tool contains a passage 162 for the slidable 
containment of the cable 20 and a hexagonal distal end 152 for 
introduction into hexagonal recess 86 in the proximal end of the threaded 
member 80. The cannulated hexagonal nut driver also contains an expanded 
hexagonal shaped proximal end 161 for the adaption of typical box end 
wrench. 
Use of the tightening tool 130 begins with the passage of the proximal end 
24 of the cable 20 (already attached distally to the locking device 10) 
through the distal end of the capturing sleeve 62. The proximal cable 24 
may then be threaded through the distal end of the threaded member and the 
distal end of the cannulated hexagonal nut driver 152 respectively. The 
cable is then fed through the cable gripping member 140 and through the 
rotatable driver 150. The cable 20 may then be gripped along its proximal 
end 24 by one's hand and pulled through the tightening tool 130 until the 
longitudinal splines 130 make solid contact into the holes (not shown) in 
the proximal end 84 of the collar 68 on the capturing sleeve 62. The 
distal aspect 50 of the collar 68 should then come to rest against the 
proximal cortex of the bone 96. The handle 154 may then be turned so as to 
shorten the distance between the trolley mechanism 151 and the bolt member 
156. The attached cable 20 would thus be drawn proximally through the 
passage 66 in the capturing sleeve 62 which is held at length by the 
longitudinal splines 136. When a predetermined tension in the cable had 
been obtained, the capturing sleeve 62 would be secured to the cable 20 by 
insertion of the threaded member 80. This would be done by using a box end 
wrench to turn the cannulated hexagonal nut driver so as to rotatably 
insert the distal end of the threaded member 80 into the annular space in 
the capturing sleeve 74. This would cause the flanges 78 to press securely 
against the cable 20 securing the implant. The cable 20 could then be 
released from tightening tool 130 by lifting the handle 146 and releasing 
the cam shaped metallic element 142 from the cable 20. The cable could 
then be withdrawn and sheared off to the length desired using a standard 
cable cutting device. 
A tightening tool (not shown) similar to that described above may also be 
provided to facilitate implantation of a locking device including a pair 
of cables and a crimper member. The tool may include a pair of pulleys for 
turning the cables and directing them in opposite directions across a pair 
of cable tensioners. Preferably, the tool also includes a crimping 
mechanism for receiving the crimper member disposed between and in line 
with the cable tensioners. The cables may be directed through the crimper 
member and a predetermined tension applied using the cable tensioners. The 
crimping mechanism may then crush the crimper member, thereby securing the 
cables and substantially locking the bones being stabilized in position. 
While the invention is susceptible to various modifications, and 
alternative forms, specific examples thereof have been shown in the 
drawings and are herein described in detail. It should be understood, 
however, that the invention is not to be limited to the particular forms 
or methods disclosed, but to the contrary, the invention is to cover all 
modifications, equivalents and alternatives falling within the spirit and 
scope of the appended claims.