Apparatus and method for fixing a ligament in a bone tunnel

There is presented a drill guide assembly for forming a transverse guide hole in a bone, the guide hole being adapted to receive a transverse screw, the guide hole intersecting a tunnel formed in the bone and adapted to receive a body to be retained in the tunnel and to receive the screw transversely of the body to secure the body in the tunnel. The drill guide assembly comprises a track member of an elongated curved configuration, the track member having a bore extending widthwise therethrough, and a curved slide track extending lengthwise thereof, a boom member having a first portion of an elongated curved configuration slidably disposed in the slide track of the track member, and a second portion for retaining a drill bit. The assembly further includes a stem member for disposition in the track member bore, the stem member having an elongated stem portion for extending into the tunnel, and a guide member for attachment to a distal end of the stem portion, the guide member having a recess therein for receiving a distal end of a drill bit retained in the boom member second portion.

FIELD OF THE INVENTION 
The present invention relates to surgical apparatus and methods in general, 
and more particularly to apparatus and methods for fixing a ligament in a 
bone tunnel. 
BACKGROUND OF THE INVENTION 
In the human knee, the anterior and posterior cruciate ligaments (i.e., the 
ACL and PCL) extend between the top end of the tibia and the bottom end of 
the femur. These ligaments play an important role in providing both static 
and dynamic stability to the knee. Often, the anterior cruciate ligament 
(i.e., the ACL) is ruptured or torn as a result of, for example, a 
sports-related injury. Consequently, various surgical procedures have been 
developed for reconstructing the ACL so as to restore stable function to 
the knee. 
For example, the ACL may be reconstructed by replacing the ruptured ACL 
with a synthetic or harvested graft ligament. More particularly, with such 
procedures, bone tunnels are typically formed in the top end of the tibia 
and the bottom end of the femur, with one end of the graft ligament being 
positioned in the femoral tunnel and with the other end of the graft 
ligament being positioned in the tibial tunnel. The two ends of the graft 
ligament are anchored in place in various ways well known in the art so 
that the graft ligament extends between the tibia and the femur in 
substantially the same way, and with substantially the same function, as 
the original ACL. 
In some circumstances, the graft ligament may include a bone block 
connected to one of its ends. This bone block may be used to attach the 
ligament graft to the patient's femur. 
For example, in one well-known procedure, the bone block is placed in the 
femoral tunnel and then fixed in place using a so-called "Kurosaka" screw. 
More particularly, with this procedure, a screw is screwed into the bottom 
end of the femur so that the screw extends parallel to the bone tunnel and 
simultaneously engages both the bone block and the femur. This screw then 
keeps the bone block (and hence the graft ligament) secured to the femur. 
More recently, interest has developed in procedures for pinning the bone 
block to the femur by passing a screw through the femur and the bone block 
so that the screw extends transverse to the bone tunnel. See, for example, 
U.S. Pat. Nos. 4,901,711; 4,985,032; 5,067,962; 5,152,764; 5,350,380; 
5,354,300; 5,397,356; and 5,431,651. 
Unfortunately, however, the various apparatus and methods disclosed in the 
foregoing patents suffer from a variety of deficiencies. 
Furthermore, in some circumstances, the graft ligament may not have a bone 
block attached to one of its ends. In this situation, it can be difficult 
to securely attach the graft ACL to the patient's femur. 
In this latter respect, some work has been done to pass a pin through the 
femur so that the pin extends transverse to the bone tunnel; the graft ACL 
is then looped over the pin to secure it to the femur. See, for example, 
U.S. Pat. Nos. 5,266,075 and 5,393,302. 
Unfortunately, however, the various apparatus and methods disclosed in the 
foregoing patents also suffer from a variety of deficiencies. 
Still other art of interest is shown in U.S. Pat. Nos. 3,973,277; 
5,004,474; 5,147,362; 5,356,435; and 5,376,119. 
OBJECTS OF THE INVENTION 
Accordingly, one object of the present invention is to provide improved 
apparatus for fixing a ligament in a bone tunnel. 
Another object of the present invention is to provide an improved method 
for fixing a ligament in a bone tunnel. 
Still another object of the present invention is to provide improved 
apparatus for attaching a graft ACL to a patient's femur. 
Yet another object of the present invention is to provide an improved 
method for attaching a graft ACL to a patient's femur. 
SUMMARY OF THE INVENTION 
These and other objects of the present invention are addressed by the 
provision and use of novel apparatus for fixing a ligament in a bone 
tunnel. 
The novel apparatus comprises a novel drill guide assembly for forming 
transverse guide holes in a bone, and novel transverse screws for fixing a 
graft ligament in a bone tunnel. 
In a preferred embodiment of the present invention, the drill guide 
assembly generally comprises a track member, a boom member, a stem member 
and a guide member. The track member has an elongated curved 
configuration. A bore extends through the track member at a first end 
thereof. A curved slide track extends inwardly from a second end of the 
track member. The boom member comprises a first portion and a second 
portion. The first portion has an elongated curved configuration which is 
adapted to be slidably disposed in the slide track of the track member. 
The second portion of the boom member has a planar configuration and 
includes a plurality of apertures extending therethrough for guiding drill 
bits or guidewires. The stem member comprises an elongated stem portion 
for extending through the bore in the track member and into the bone 
tunnel. The guide member is attached to the distal end of the stem 
portion, and has at least one recess therein for receiving distal ends of 
the drill bits received in the apertures of the boom member. 
In accordance with a further feature of the present invention, there are 
provided transverse screws for fixing a ligament in a bone tunnel. 
The transverse screws include a compression screw for compressing a bone 
plug against a wall portion of the bone tunnel, the compression screw 
having a concave distal end. 
The transverse screws further include a transfixation screw for fixing the 
bone plug and/or its associated ligament to a wall portion of the bone 
tunnel, the transfixation screw having a pointed distal end for 
penetration of the bone plug and/or the ligament, and the bone tunnel 
wall. 
The transverse screws still further include a combination transfixation and 
compression screw for compressing the bone plug against a wall portion of 
the tunnel and/or for fixing its associated ligament to the bone tunnel 
wall, the combination screw having, proximate a distal end thereof, a 
shoulder for engaging and pressing against the bone plug and/or the 
ligament, and a pin portion extending distally from the shoulder and 
pointed at the distal end thereof for penetration of the bone plug and/or 
the ligament, and the bone tunnel wall. 
In accordance with a further feature of the present invention, there is 
provided a method for fixing a ligament in a bone tunnel, the method 
comprising the steps of: (i) drilling a tunnel in the bone, and providing 
a drill guide assembly comprising a track member having, at a first end 
thereof, a bore therethrough and having, extending inwardly thereof from a 
second end thereof, a slide track, the drill guide assembly further 
comprising a boom member having a first portion slidably disposed in the 
slide track of the track member and a second portion having an aperture 
therethrough, a stem member having an elongated stem portion, and a guide 
member having a recess therein, the guide member being fixed to the distal 
end of the stem member; (ii) positioning the stem member in the track 
member bore and the guide member at a selected location within the tunnel; 
(iii) placing a drill bit in the boom member's aperture, sliding the first 
portion of the boom member in the slide track of the track member so as to 
position the drill bit at a selected angle relative to the guide member, 
and locking the boom member to the track member; (iv) advancing the drill 
bit through the aperture in the boom member and into the recess of the 
guide member so as to form a transverse hole in the bone; (v) withdrawing 
the drill bit from the bone and withdrawing the stem member and the guide 
member from the tunnel; and (vi) fixing the ligament in the bone tunnel by 
means of a transverse screw extending through the transverse hole. 
In one form of the invention, the graft ligament includes a bone block at 
its distal end which is made fast in the bone tunnel by passing a 
transverse screw through the transverse hole so that the transverse screw 
engages the graft ligament. In this situation, the guide member preferably 
comprises a guide plug having a recess therein for receiving the distal 
end of the drill bit. 
In another form of the invention, the graft ligament does not include a 
bone block at its distal end, and the graft ligament is simply looped over 
a transverse element which is passed through the transverse hole and 
across the bone tunnel. In this situation, the guide member preferably 
comprises a guide yoke having two legs defining a gap therebetween.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring first to FIG. 1, there is shown an illustrative embodiment of the 
inventive drill guide assembly 5, shown in conjunction with a tibia 10 and 
a femur 15 of a human knee joint. In substituting an artificial or 
harvested ligament for a damaged knee ligament, it is customary to drill a 
bone tunnel 16 through tibia 10 and another bone tunnel 17 into femur 15. 
A bone plug 18 (FIG. 8) having ligament material 19 fixed thereto is 
passed through the tibial tunnel 16 and into the femoral tunnel 17 for 
disposition within femoral tunnel 17. The drill guide assembly 5 shown in 
FIG. 1 is intended to be used to drill transverse holes 20 into femur 15. 
These transverse holes 20 receive transverse screws 21 (FIG. 8) so as to 
secure bone plug 18 in femur 15. 
The drill guide assembly 5 includes a track member 22, a boom member 40, a 
stem member 60, and a guide plug 70 connected to the distal end of stem 
member 60. The boom member 40 includes a portion 44 adapted to receive 
drill bits 90 for drilling the transverse holes 20. As mentioned above, 
the transverse holes 20 are thereafter adapted to receive transverse 
screws 21 (FIG. 8) for securing bone plug 18 in femoral tunnel 17. 
Referring next to FIGS. 2 and 3, it will be seen that the track member 22 
has an elongated curved configuration. Track member 22 includes a first 
end 95. A bore 100 extends through track member 22 adjacent to first end 
95. Bore 100 has a tapered configuration, such that its distal end (i.e., 
the end disposed closer to femur 15) is larger than its proximal end 
(i.e., the end disposed farther from femur 15). A slot 103 extends along 
the length of bore 100. A collet 105 is disposed in bore 100. Collet 105 
also has a tapered configuration, such that its distal end (i.e., the end 
disposed closer to femur 15) is larger than its proximal end (i.e., the 
end disposed farther from femur 15). A slot 108 extends along the length 
of collet 105. The collet's slot 108 is aligned with the track member's 
slot 103, for reasons which will hereinafter be made clear. Collet 105 is 
formed out of a resilient material, e.g., plastic or metal. Track member 
22 also includes a second end 110. A curved slide track 115 extends 
inwardly from second end 110. The curvature of slide track 115 conforms to 
the curvature of track member 22. 
In FIG. 4, there is shown boom member 40. Boom member 40 has a first 
portion 120 of an elongated curved configuration which is complementary to 
slide track 115 in track member 22 so that the boom member's first portion 
120 can be slidably disposed in slide track 115 (FIG. 1). The boom member 
40 also includes the second portion 44 which has a substantially planar 
configuration. The second portion 44 of boom member 40 is provided with a 
plurality of apertures 125 therethrough. An intermediate portion 130 
interconnects the boom member's first portion 120 and second portion 44. 
A thumbscrew 135 (FIGS. 1-3) is mounted in track member 22 and is adapted 
to lock the boom member's first portion 120 in a selected position in 
slide track 115 by manipulation of a grip portion 140. Manipulation of 
grip portion 140 releases the boom member's first portion 120 for movement 
in slide track 115. Preferably, the boom member's first portion 120 is 
provided with indicia 145 (FIGS. 1 and 4) indicative of the angular 
positioning of boom member 40 in track member 22, as will be further 
discussed hereinbelow. 
The track member 22 has a handle 150 (FIGS. 1 and 2) and a spring 165 
mounted thereon. One end of spring 165 engages the proximal end of collet 
105 and the other end of spring 165 engages track member 22, whereby 
spring 165 normally biases collet 105 proximally in bore 100. However, 
handle 150 is arranged so that when it is moved towards track member 22, 
spring 165 will move collet 105 distally within bore 100. In this respect 
it is to be appreciated that, by virtue of the tapered configurations of 
bore 100 and collet 105, and by virtue of the collet's resilient nature 
and its slot 108, collet 105 will be in a "closed down" position when it 
is moved proximally within bore 100 by spring 165, and collet 105 will be 
in an "opened up" position when it is moved distally within bore 100 by 
handle 150. Furthermore, it is to be appreciated that when stem member 60 
is disposed within collet member 105 (FIG. 1), collet member 105 will 
normally tightly grip the stem member's enlarged proximal portion 166, due 
to the biasing action of spring 165, but collet member 105 can be induced 
to release its grip on stem member 60 by depressing handle 150. 
It should also be appreciated that the arrangement of bore 100, collet 105, 
handle 150 and spring 165 is generally similar to the corresponding 
arrangement taught in U.S. Pat. No. 5,154,720 issued Oct. 13, 1992 to 
Trott et al., which patent is hereby incorporated herein by reference. 
Referring next to FIGS. 5 and 6, it will be seen that the boom member's 
second portion 44 includes a pivotally mounted plate 170 secured to, and 
released from, second portion 44 by a thumbscrew 175. By manipulation of 
thumbscrew 175, plate 170 may be released from, and pivotally moved 
outwardly from, second portion 44 (FIG. 6) so as to permit drill bits 90 
to be laterally released from apertures 125. This feature is very useful 
in the situation where the drill guide assembly 5 must be removed from the 
surgical site while the drill bits 90 (or guidewire 305, as will 
hereinafter be discussed) remain embedded in the femur. 
Referring next to FIG. 7, it will be seen that the stem member 60 includes 
a handle portion 180 adjacent to the enlarged proximal portion 166, and an 
elongated stem portion 185. The elongated stem portion 185 is sized so as 
to be slightly thinner than the width of the track member's slot 103, and 
slightly thinner than the width of the collet's slot 108 when the collet 
has been moved distally by means of handle 150, whereby the elongated stem 
portion 185 can be passed through the slots. The elongated stem portion 
185 is connectable, at a distal end 190 thereof, to the guide plug 70. 
Guide plug 70 has a series of recesses 195 therein, preferably in the form 
of annular grooves 197 encircling guide plug 70. 
As shown in FIG. 1, the track member's bore 100 receives collet 105 and 
collet 105 receives stem member 60, with guide plug 70 fixed thereon. Stem 
member 60 can gain access to the interior of collet 105 by (i) depressing 
handle 150 so as to move collet 105 distally whereby it will open its slot 
108, and (ii) slipping the stem member's reduced-diameter stem portion 185 
through the aligned slots 103 and 108. It will be appreciated that stem 
member 60 can exit the interior of collet 105 by reversing the foregoing 
procedure. 
The stem member 60 is intended to be inserted axially into tibial tunnel 16 
and then femoral tunnel 17 until guide plug 70 occupies the position in 
which bone plug 18 ultimately will be disposed. When guide plug 70 is 
correctly positioned in femoral tunnel 17, handle 150 can be released so 
that collet 105 will move proximally until it securely grips the guide 
member's enlarged proximal portion 166. The annular grooves 197 on guide 
plug 70 will be correctly aligned with the apertures 125 of the boom 
member's second portion 44 when the handle portion 180 stem member 60 is 
seated on the proximal surface of collet 105. The guide plug 70 is of a 
slightly lesser diameter than femoral tunnel 17. The thumbscrew 135 is 
manipulated by an operator to permit sliding movement of the boom's first 
portion 120 in slide track 115 of track member 22. If it is desired that 
transverse screws 21 be brought to bear on the bone plug and/or ligament 
at right angles to the axis of the femoral tunnel 17, thumbscrew 135 is 
fixed when the marking "0" on the boom's first portion 120 is aligned with 
a base mark 200 on track member 22, as illustrated in FIG. 1. 
The intermediate portion 130 (FIG. 4) of boom member 40 inclines from the 
boom member's first portion 120 toward stem member 60 so as to place the 
boom member's second portion 44 closer to guide plug 70 than would be the 
case if intermediate portion 130 were merely an extension of first portion 
120. The incline of intermediate portion 130 places second portion 44 in a 
position proximate to, and opposed to, guide plug 70, as shown in FIG. 1. 
With track member 22 and boom member 40 locked together with the base mark 
200 at the setting "0", the boom member's second portion 44 is disposed 
parallel to guide plug 70 and its apertures 125 are disposed normal to the 
axis of guide plug 70 and in alignment with the guide plug's annular 
grooves 197. In particular, at this drill guide setting, each of the 
apertures 125 is in alignment with one of the annular grooves 197. 
The apertures 125 are adapted to receive drill bits 90 of a length 
sufficient to extend through the nearest wall portion 205 and the farthest 
wall portion 210. Markings 91 on drill bits 90 are used to indicate the 
depth to which the drill bits 90 have penetrated. Each of the drill bits 
90 is adapted to be secured to a chuck 215 (FIG. 1) of a drill (not shown) 
for drilling operations. Drill bits 90 are provided in varying lengths so 
that a first (i.e., shorter) drill bit 90A can be left positioned in the 
femur while a second (i.e., longer) drill bit 90B is drilled in close to 
the first drill bit 90A; the increased length of the second drill bit 90B 
allows it to be driven into the femur without the drill's chuck striking 
the already-emplaced first drill bit 90A. 
Alternatively, apertures 125 can be adapted to receive bushings (not shown) 
having holes dimensioned, respectively, to receive tools such as drill 
bits, guide wires, and the like. In such case, the boom member's second 
portion 44 is provided with means of the sort well known in the art (not 
shown) for locking the bushings in the apertures 125. 
If desired, the boom member's second portion 44 can also be provided with 
locking means of the sort well known in the art (not shown) such as 
thumbscrews for locking the tools in the apertures 125. 
In FIGS. 9, 10 and 12, there are shown various embodiments of transverse 
screws 21, including a compression screw 220 (FIG. 9), a transfixation 
screw 225 (FIG. 10) and a combination transfixation and compression screw 
230 (FIG. 12). 
The compression screw 220 is provided with a concave distal end 235. The 
compression screw 220 is used for compressing the bone plug 18 against the 
farthest femoral tunnel wall portion 210, as shown in FIG. 8. Typically, 
the bone plug wall facing the screw's concave distal end 235 is of 
relatively hard cortical bone, and the bone plug wall facing the tunnel 
wall portion 210 is of relatively soft cancellous bone. This permits the 
cancellous portion of the bone plug to be pressed into close engagement 
with the femur's tunnel wall portion 210, whereupon the portions of bone 
may thereafter grow together. 
The transfixation screw 225 (FIGS. 10 and 11) is provided with a pointed 
distal end 240 for penetration of bone plug 18 and/or ligament material 
19, and farthest wall portion 210 of femoral tunnel 17. In FIG. 11, there 
are shown two transverse screws 21 of the transfixation type 225, one 
shown extending through the bone plug 18 and into the farthest wall 210, 
and a second shown extending through ligament material 19 and into the 
farthest wall 210. 
The compression screws 220 and transfixation screws 225 may be used in 
various combinations. For example, one or more of the compression screws 
220 may be used to secure bone plug 18, as shown in FIG. 8, and one or 
more of the transfixation screws 225 may be used to support bone plug 18 
and/or ligament material 19, and/or to act as stop members for bone plug 
18, as shown in FIG. 11. 
Referring next to FIG. 12, it will be seen that the combination 
transfixation and compression screw 230 is provided, proximate the distal 
end thereof, with (i) a shoulder 245 for engaging and pressing against 
bone plug 18 and ligament material 19, and (ii) a pin portion 250 
extending distally from shoulder 245 and pointed at a distal end 255 for 
penetration of bone plug 18 and/or ligament material 19, and farthest wall 
210. As shown in FIG. 13, one or more of the combination screws 230 may be 
used such that pin portion 250 extends into bone plug 18 and shoulder 245 
engages and presses against bone plug 18, and one or more of the 
combination screws 230 may be used such that shoulder 245 presses against 
ligament material 19 while pin portion 250 extends through the ligament 
material 19 and into farthest wall 210 of femoral tunnel 17. In the 
embodiment shown in FIG. 13, the ligament-engaging combination screw 230A 
(i.e., the proximal-most screw 230) may be deployed first and the bone 
plug 18 then pulled down against the screw, whereupon the distal-most 
combination screw 230B (as shown in FIG. 13) may be advanced into bone 
plug 18 so as to secure the bone plug in femoral tunnel 17 by transfixing 
and compressing bone plug 18 against farthest wall portion 210. In such an 
arrangement, the proximal-most screw 230A serves to pin ligament material 
19 against tunnel wall 210 and further serves as a stop member and support 
member for bone plug 18. 
The transverse screws 21 are each provided with screw threads 260 near the 
proximal end thereof, and are not threaded near the distal end of the 
screw. The threads 260 thus facilitate securely locking transverse screws 
21 in holes 20, but do not engage bone plug 18 or ligament material 19, 
and therefore do not threaten the integrity of the bone plug and the 
associated ligament material. Transverse screws 21 are headless, so that 
they may be buried in femur 15 and not protrude above the outer surface of 
the femur. Additionally, since transverse screws 21 are headless, they may 
be advanced however far into femur 15 as may be required to achieve the 
degree of graft penetration or compression desired. 
In operation, the drill guide assembly 5 is positioned relative to the knee 
joint as shown in FIG. 1, track member 22 and boom member 40 being locked 
together in a selected relationship to place apertures 125 at a desired 
angle relative to guide plug 70. Drill bits 90 are then used to drill 
guide holes 20. For example, where two guide holes 20 are intended to be 
drilled into the femur, and where these drill bits may or may not be left 
in the femur for some period of time after drilling, a shorter drill bit 
90A and a longer drill bit 90B would be used. First the shorter drill bit 
90A is drilled into the bone. When this occurs, one of the annular grooves 
197 of guide plug 70 receives the pointed end of drill bit 90A so that a 
guide hole 20 is fully formed from the entry point on femur 15 into the 
femoral tunnel 17. Then the longer drill bit 90B is used to drill an 
additional hole 20. Since drill bit 90B is longer than the 
already-deployed drill bit 90A, the drill bit 90B can be placed close to 
drill bit 90A without the chuck of the drill striking the emplaced drill 
bit 90A. Drill bits 90 are withdrawn and the drill guide assembly removed, 
and bone plug 18 is then installed in femoral tunnel 17 using techniques 
well known in the art. 
Transverse screws 21 are then screwed into guide holes 20 so as to engage 
bone plug 18 and/or ligament material 19 in the manner previously 
discussed. Transverse screws 21 will thus secure bone plug 18 and ligament 
material 19 in femoral tunnel 17. The transverse screws 21 are headless so 
as to permit the screws to be buried completely in femur 15. In addition, 
since the transverse screws 21 are headless, they can be advanced as far 
into femur 15 as may be required to achieve the degree of graft 
penetration or compression desired. 
Certain aspects of drill guide assembly 5 should be noted. 
For one thing, it should be appreciated that the central longitudinal axis 
of the stem member 60 and the central longitudinal axes of the apertures 
125 are disposed in the same plane. 
Furthermore, the longitudinal axis of the stem member 60 will intersect, 
when stem member 60 is properly seated within collet 105, the longitudinal 
axes of the apertures 125. By the same token, drills or guidewires 
advanced through the apertures 125 with a sliding fit will intersect the 
longitudinal axis of the stem member 60 and, in particular, recesses 195 
in guide plug 70. 
In addition to the foregoing, it should be appreciated that the axis of 
rotation for track member 22 intersects the longitudinal axis of the stem 
member 60. This axis of rotation is oriented perpendicular to the plane 
defined by the longitudinal axis of the stem member 60 and the 
longitudinal axes of the apertures 125. The axis of curvature for track 
member 22 (and the point of intersection between the longitudinal axis of 
stem member 60 and the longitudinal axes of apertures 125) is preferably 
located within the guide plug 70. 
FIG. 14 is illustrative of an alternative procedure in which the inventive 
drill guide finds applicability. In the procedure illustrated, the guide 
plug 70 is replaced with a guide yoke 270 (FIGS. 15 and 16) having a base 
portion 275 and two elongated substantially parallel legs 280 extending 
therefrom and defining therebetween a gap 285 (FIG. 16). Each leg 280 is 
provided with a notch 290 (FIG. 15) on its distal end. The guide member's 
handle portion 180 includes an orientation mark 292 which has a predefined 
orientation relative to guide yoke 270 whereby, when guide yoke 270 is 
disposed within femoral tunnel 17, the orientation of guide yoke 270 can 
be determined by observing the position of orientation mark 292. 
Preferably orientation mark 292 is arranged so that when orientation mark 
292 is aligned with slot 103 in track member 22 and slot 108 in collet 
105, the guide yoke's gap 285 will be aligned with a drill bit in the boom 
member's apertures 125. If desired, orientation mark 292 can be replaced 
with equivalent mechanical means of the sort well known in the art (not 
shown) for enabling alignment of the guide yoke's gap 285. 
The object of the procedure illustrated in FIG. 14 is to suspend a ligament 
295 over a cross-pin in the femoral tunnel 17, where the ligament 295 does 
not have a bone plug on its end. To do so, the ligament 295 is attached at 
one end to an end of a suture 300, or the like. The suture 300 is strung 
through the guide yoke's leg notches 290, bridging the gap 285 proximate 
the distal end of guide yoke 270. The suture 300 is passed into femoral 
tunnel 17 by movement of guide yoke 270 through tibial tunnel 16 and into 
femoral tunnel 17. With the enlarged proximal portion 166 of stem member 
60 positioned within collet 105, and with handle 150 depressed so as to 
permit the stem member's enlarged proximal portion 166 to move within the 
collet, the handle portion 180 of stem member 60 is rotated until the 
orientation mark 292 is aligned with slot 103 in track member 22 and slot 
108 in collet 105. In this position, the guide yoke's gap 285 will be 
aligned with the apertures 125 of second portion 44. The stem member 60 is 
then locked in place by releasing the handle portion 150 of track member 
22. As shown in FIG. 14, at this point the two ends of suture 300 extend 
from the tibial tunnel 16, with ligament 295 fixed to one of the two ends. 
When guide yoke 270 is properly positioned in femoral tunnel 17, a drill 
bit 90 (mounted in one of the apertures 125 of second portion 44 of boom 
member 40) is drilled into femur 15, using the above-described drill guide 
for proper alignment of drill bit 90 with guide yoke 270. The drill guide 
directs drill bit 90 through guide yoke gap 285. The drill bit 90 
continues into farthest femoral tunnel wall portion 210. The drill bit 90 
is then withdrawn and the guidewire 305 is inserted into the hole 20 
created by the drill bit 90, and drilled or tapped further into the 
femoral tunnel wall portion 210 than was the drill bit 90 (FIG. 17). 
Alternatively, the use of drill bit 90 can be omitted, and the drill guide 
assembly can be used to drill or tap guidewire 305 directly into place in 
femur 15. 
With the guidewire 305 securely in place in the guide yoke gap 285, the 
guide yoke 270 is withdrawn from the femoral tunnel 17. This is done by 
depressing handle 150 so as to free stem member 60 from collet 105, and 
then withdrawing the stem member proximally. As the guide yoke 270 moves 
toward the tibia 10, suture 300 remains looped around guidewire 305, and 
leaves the notches 290 (FIG. 18). The stem member 60 may then be removed 
from the drill guide by slipping the elongated stem portion through the 
collet's slot 108 and the track member's slot 103. 
By pulling the free end of suture 300, the operator may then pull ligament 
295 through tibial tunnel 16 and up into femoral tunnel 17 (FIG. 19). 
Further pulling on the free end of suture 300 will pull ligament 295 up 
around guidewire 305 (FIG. 20) and then back down to the lower opening of 
tibial tunnel 16, where the two free ends of ligament 295 may be 
positioned for attachment to tibia 10 in ways well known in the art (not 
shown). 
A cannulated transverse screw 310 (FIG. 20) is then advanced on the 
guidewire 305 and into hole 20 (FIG. 20). Transverse screw 310 is then 
advanced further, so that it passes through the looped ligament 295 (FIG. 
21) and into femoral tunnel wall portion 210. Once the screw 310 is 
securely in place, the guidewire 305 may be removed from inside the screw 
310 (FIG. 21) and withdrawn from femur 15, leaving ligament 295 looped 
around transverse screw 310. In order to facilitate passage of transverse 
screw 310 through the loop of ligament 295 resting on guidewire 305, the 
distal end of screw 310 is inclined at 315 (FIG. 20) and has a smooth 
outer configuration along a first portion 320 of its shaft. A second 
portion 325 of its shaft is threaded so as to facilitate securely locking 
the transverse screw 310 in hole 20. 
In FIGS. 22 and 23, there is shown an alternative embodiment of track 
member 22A, wherein there is provided a thumb screw 330 engageable with 
collet 335 and adapted to squeeze collet 335, by tightening down of thumb 
screw 330, to lock stem member 60 therein. Loosening of thumb screw 330 
releases pressure on collet 335 to permit expansion of collet 335, which 
is a split collet (FIG. 23), to loosen the stem member 60 for backing stem 
member 60 out of collet 335. It is to be appreciated that collet 335 (like 
collet 105 described above) is not large enough to permit passage of guide 
plug 70 therethrough. Upon the guide plug 70 encountering collet 335, 
aligned slots 340, 345 in collet 335 and track member 22A, respectively, 
permit sidewise movement of the elongated stem portion 185 of stem member 
60 from the confines of collet 335. 
It is to be appreciated that the track member 22 and collet 105 of FIG. 2 
have the same sidewise escape feature (i.e., slot 108 in collet 105 and 
slot 103 in track member 22). However, in the embodiment shown in FIG. 2, 
the handle 150 serves to longitudinally move the collet 105 to the point 
where it releases its grip on stem member 60, and in the embodiment shown 
in FIG. 22, the thumbscrew 330 serves to loosen the collet 335 such that 
it no longer binds the stem member 60. 
It is also to be appreciated that, after creating the transverse drill 
holes 20 as illustrated in FIGS. 1 and 14, the unique design of drill 
guide assembly 5 allows it to be quickly and easily detached from the 
drills 90 (and/or guidewire 305) and stem member 60 while leaving the 
drills 90 (and/or guidewire 305) and stem member 60 in-situ. The stem 
member 60 is released from the grip of the collet 105 by depressing the 
handle portion 150 of track member 22. Then, by sidewise movement of the 
slender portion 185 of stem member 60 past the aligned slots 108 and 103 
in collet 105 and track member 22, respectively, the stem member 60 
escapes from the confines of the drill guide assembly 5. Furthermore, by 
unlocking movement of thumbscrew 175, plate 170 may be released from, and 
pivotally moved outwardly from, the drill guide's second portion 44 (FIG. 
6) so as to allow quick release of drill bits 90 (and/or guidewire 305) 
from apertures 125. The disengagement of the drills 90 (and/or guidewire 
305), and stem member 60, from the drill guide assembly 5 can be further 
facilitated by unlocking movement of thumbscrew 135 to allow the first 
portion 120 of boom member 40 to slide along slide track 115 in track 
member 22. 
FIGS. 24-26 show an alternative boom member 40A. In this construction, 
intermediate portion 130A slidingly supports a tray portion 342 of boom 
member second portion 44A, such that portion 44A may be slid toward or 
away from guide plug 70 (or guide yoke 270). The tray portion 342 is 
provided with recesses 345 into which a spring-biased detent 350 of the 
intermediate portion 130A may releasably snap-lock, or tray portion 342 
may be provided with any other suitable releasable locking device for 
locking tray portion 342 in a selected position on intermediate portion 
130A. 
There is thus provided a drill guide assembly wherein transverse hole 
drilling bits may be operated at a selected angle to the axis of the bone 
tunnel. There is further provided a drill guide assembly wherein a 
plurality of hole drilling bits may be employed to provide a plurality of 
transverse holes intercepting the bone tunnel, such that transverse screws 
(selected from different types of transverse screws) may be disposed in 
the holes to penetrate and/or impinge upon and/or pass through a bone plug 
and/or associated ligament material and/or sutures, in different 
locations, to effect different modes of holding. There are still further 
provided methods for forming tunnels in bones and for fixing bone plugs 
and ligaments in such tunnels. 
While access to the femoral tunnel 17 has been described hereinabove as 
being obtained via the tunnel 16 extending through the tibia 10, and while 
such is a common undertaking, such is not necessary in practicing the 
inventive methods herein described nor for use of the inventive drill 
guide and/or transverse screws. For example, as illustrated in FIG. 27, 
the skin near the upper plateau of the tibia may be opened at 355, whereby 
the guide plug 70 (and/or the guide yoke 270) may be introduced into 
femoral tunnel 17. 
It is also to be appreciated that, as shown in FIG. 27, tibial tunnel 16 
and femoral tunnel 17 need not necessarily be co-linear with one another. 
In fact, in some circumstances, tibial tunnel 16 and femoral tunnel 17 can 
be significantly divergent (i.e., non-co-linear). 
Furthermore, in this respect, it should be appreciated that the unique 
construction of drill guide assembly 5 permits the surgeon significant 
freedom in selecting the optimal angles of approach when cross-pinning a 
graft ligament in femur 15. For example, in FIG. 27, a skin incision 355 
may be used to form and gain access to a femoral tunnel 17 (which is not 
aligned with tibial tunnel 16) in the course of cross-pinning a graft 
ligament in femur 15. It should be noted that, in the exemplary case shown 
in FIG. 27, base mark 200 on track member 22 is aligned with the marking 
"15" rather than with the marking "0" as previously shown in FIG. 1. 
Referring next to FIG. 28, there is shown a novel drill bit 360 having 
particular utility in connection with fixing a bone plug in a bone in the 
vicinity of a joint as, for example, fixing a bone plug in the femur in 
the vicinity of the knee joint. Drill bit 360 includes a head portion 365 
and a stem portion 370. The head portion 365 is provided with bore cutting 
means 375, such as the usual cutting teeth extending generally helically 
around the drill head. The stem portion 370 is of a widthwise dimension 
substantially less than the diameter of head portion 365. Such drill bits 
are sometimes referred to as "acorn bits". After the head portion 365 
advances through the tibia 10, there is defined in the tibia the tibial 
tunnel 16, which is generally of the same diameter as head portion 365. 
However, in view of the slender configuration of stem portion 370, the 
stem portion 370 may be moved about in tibial tunnel 16 as needed so as to 
place the drill bit head portion 365 at an appropriate entry point on the 
femur 15. Thus, tibial tunnel 16 and femoral tunnel 17 need not be in 
precise alignment with one another, affording a degree of flexibility in 
positioning of the tibia 10 and femur 15, and in the disposition of tibial 
tunnel 16 relative to femoral tunnel 17. 
The drill bit head portion 365 may be provided with recesses 380 serving 
the same purpose as recesses 195 of guide plug 70. For example, recesses 
380 might comprise annular grooves 385 similar to the annular grooves 197 
in guide plug 70. In such instance, the head portion 365 can serve not 
only as a drill head, but also as a guide plug. 
In an alternative method, utilizing the aforementioned "acorn bit" 360 in 
the knee joint, head portion 365 of bit 360 is advanced through tibia 10 
to define bone tunnel 16 therethrough. The tibia 10 and femur 15 are then 
positioned for desired placement of bone tunnel 17 in femur 15. The drill 
bit 360 is angled (FIG. 28) in tibial tunnel 16 for placement of drill bit 
head portion 365 on femur 15 at a selected entry point for femoral tunnel 
17, and drill bit 360 is advanced into femur 15 at the selected entry 
point. A drill guide assembly 5, such as described above, or similar 
thereto, is provided, and one or more transverse drill bits 90 in the 
drill guide are advanced through femur 15 to define transverse holes 20 
extending into femoral tunnel 17. The transverse drill bits 90 are 
withdrawn and the femoral tunnel 17 is vacated. The bone plug 18 is then 
placed in the femoral tunnel 17 and transverse screws 21 are advanced 
through transverse holes 20 to engage bone plug 18 to secure bone plug 18 
in femur 15. 
In one embodiment of the method described immediately above, drill bit head 
portion 365 is provided with one or more recesses 380 and the transverse 
drill bits 90 are advanced into the recesses 380. With this embodiment of 
the invention, a separate guide plug 70 (having one or more of the 
recesses 195 therein) does not have to be provided. In another embodiment 
of the invention, there is provided the guide plug 70 having one or more 
of the recesses 195 therein. In this latter embodiment, the drill bit head 
portion 365 is removed from femoral tunnel 17 prior to advancement of the 
transverse drill bits 90. More particularly, with this latter embodiment 
of the invention, the drill bit head portion 365 is removed from the 
femoral tunnel 17 after the femoral tunnel has been formed, next the guide 
plug 70 is inserted into the femoral tunnel 17, and then the transverse 
drill bits 90 are advanced into the guide plug recesses 195. 
It should be understood that various modifications, variations and changes 
may be made to the above-disclosed novel drill guide assembly, transverse 
screws and drill bit, and the above-described methods, without departing 
from the spirit and scope of the present invention. For example, while the 
above-described devices and methods have been described and shown with 
respect to a femur-tibia joint, and while the aforesaid devices and 
methods are believed to have particularly beneficial applicability to such 
joints, it will be appreciated that the devices described herein find 
utility with respect to bones generally and should not be deemed limited 
to simply the femur and tibia bones. Further, when two bones are involved, 
it is clear that the near (i.e., proximal) tunnel can be made in either 
bone (e.g., the femur), that the drill guide device can be used in any 
attitude as, for example, upside-down from the arrangement shown in FIG. 
1, and that bone plugs can be secured in both bones following the 
teachings of the present invention. It will further be appreciated that 
the methods described herein have been limited to the inventive steps of 
the methods and have omitted many surgical steps required and well-known 
in the art, from initiating stab wounds in the skin proximate selected 
bone entry points so as to make such points accessible, to suturing such 
incisions at the conclusion of the operation.