Patent Description:
A ligament is a piece of soft, fibrous tissue that connects one bone to another bone in the skeletal system. Ligaments can often become damaged or injured. When damaged or injured, ligaments may tear, rupture or become detached from bone. The loss of a ligament can cause instability, pain and eventually increased wear on joint surfaces, which can lead to osteoarthritis.

Various surgical techniques have been developed for ligament repair. The particular surgical technique used depends on the ligament that has been damaged and the extent of the injury.

One ligament which is commonly injured is the anterior cruciate ligament (ACL). As seen in <FIG>, the ACL <NUM> extends from the top of the tibia <NUM> to the side of the notch <NUM> which is located between the femoral condyles <NUM> of the femur <NUM>.

Trauma to the knee can cause injury to the ACL. The ACL may become partially or completely torn. <FIG> is a schematic view showing a torn ACL <NUM> in the left knee. An intact posterior cruciate ligament (PCL) <NUM> is shown behind the torn ACL <NUM>.

A torn ACL reduces the stability of the knee joint and can result in pain, instability and excessive wear on the cartilage surfaces of the knee, eventually resulting in osteoarthritis.

Several approaches are available for ACL reconstruction. One of the most commonly used ACL reconstruction techniques involves removal of most, or all, of the torn ACL, drilling bone tunnels in both the femur and the tibia, inserting a tissue graft (sometimes referred to herein as simply "the graft") into the tibial and femoral tunnels so that the tissue graft extends across the interior of the knee joint in place of the native ACL, and securing the tissue graft in the femoral and tibial tunnels with interference screws or other fixation devices, so that the graft extends from the top of the tibia to the side of the femoral notch.

More particularly, and looking now at <FIG>, an aiming instrument <NUM> is aligned to tibia <NUM> and a tibial guide pin <NUM> (for guiding a cannulated drill, see below) is drilled into tibia <NUM>. <FIG> illustrates a typical aiming instrument <NUM> for targeting the tibial guide pin <NUM> from the outside of tibia <NUM> to an exit point <NUM> on the tibial plateau <NUM> at the location corresponding to the insertion point of the natural ACL. Note that tibial guide pin <NUM> enters tibia <NUM> at an angle α relative to the plane of tibial plateau <NUM>, and exits the tibial plateau at the same angle α (relative to the plane of the tibial plateau).

After tibial guide pin <NUM> has been appropriately drilled through the tibia, aiming instrument <NUM> is removed from the tibia, leaving tibial guide pin <NUM> in place. As seen in <FIG>, a cannulated drill <NUM> (i.e., a drill with a center hole extending along the length of the drill) is slid over tibial guide pin <NUM> and drilled from the anteromedial surface of tibia <NUM>, through the tibia and into the joint space <NUM> of the knee. <FIG> shows tibial guide pin <NUM> and cannulated drill <NUM> after cannulated drill <NUM> has been drilled through tibia <NUM>. In this way a tibial tunnel <NUM> may be formed in tibia <NUM>, with the tibial tunnel extending from the anteromedial surface of the tibia to the insertion point of the native ACL on the tibial plateau.

A similar process may be followed for drilling into femur <NUM>, i.e., a femoral guide pin <NUM> may be inserted through tibial tunnel <NUM> and into femur <NUM> as shown in <FIG>, and then a cannulated drill <NUM> may be drilled over the femoral guide pin <NUM> and into femur <NUM>. In this way a femoral tunnel <NUM> may be formed in femur <NUM>, with the femoral tunnel extending from the side of the femoral notch to part or all the way through the femur. Ideally, the joint-side mouth of femoral tunnel <NUM> is located at the insertion point of the native ACL on the femoral notch.

The method described above and shown in <FIG> is sometimes referred to as "transtibial femoral tunnel drilling", since femoral tunnel <NUM> is drilled using access through tibial tunnel <NUM>. One problem with transtibial femoral tunnel drilling is that the location of the joint-side mouth of femoral tunnel <NUM> typically ends up being higher in the femoral notch <NUM> than the insertion point of the natural ACL, because access to the femur is limited by the location and size of tibial tunnel <NUM>.

On account of the foregoing, an alternative method has been developed to create femoral tunnel <NUM>, i.e., by drilling the femoral tunnel using access through the "accessory medial portal". More particularly, accessory medial portal drilling of the femoral tunnel involves drilling across the knee joint through a medial portal skin incision <NUM> such that the joint-side mouth of femoral tunnel <NUM> can be placed in a more anatomic position. In accessory medial portal drilling, and looking now at <FIG>, femoral guide pin <NUM> is first passed through medial portal skin incision <NUM> and is then drilled into the desired anatomic location on the femur (i.e., the insertion point of the natural ACL on the femur). Then a cannulated drill <NUM> is slid over femoral guide pin <NUM> and drilled into femur <NUM> so as to form femoral tunnel <NUM>. Thus, femoral guide pin <NUM> and cannulated drill <NUM> enter through medial portal skin incision <NUM> and traverse across joint space <NUM> to the side of the femoral notch. As seen in <FIG>, femoral guide pin <NUM> and cannulated drill <NUM> must enter in front of the adjacent femoral condyle <NUM> in order to prevent damaging the condyle. The knee quite often must be put into a state of deep flexion in order to reach the desired location (i.e., the insertion point of the natural ACL on the femur) and safely pass by the adjacent condyle <NUM> and tibial plateau <NUM>.

Accessory medial portal drilling is generally considered to represent an improvement over transtibial femoral tunnel drilling in the sense that it can be used to create a more anatomic ACL reconstruction.

After tibial tunnel <NUM> and femoral tunnel <NUM> have been created, the tissue graft is prepared. The tissue graft is typically harvested from the patient's own body tissue and may comprise hamstring tendons, quadriceps tendons, and/or patellar tendons. Alternatively, similar tissue grafts may be harvested from a donor and also include Achilles tendons, anterior tibialis tendons or other graft sources. Looking now at <FIG>, a tissue graft <NUM> is prepared by creating one or more long tissue graft strands or graft bundles <NUM>, folding the graft over onto itself so as to create a folded section or loop <NUM>, and making measurements along the graft. Example measurements for adults are <NUM> of graft length for the portion of the graft that is to be inserted into femoral tunnel <NUM>, <NUM> to <NUM> for the portion of the graft that is intra-articular (i.e., inside the knee joint <NUM>) and <NUM> for the portion that is to be positioned inside tibial tunnel <NUM>. <FIG> shows tissue graft <NUM> folded over into two graft bundles <NUM> and a folded section or loop <NUM>, and the corresponding graft measurements. Sutures (whipstitches) are typically applied at the areas of the graft that will interface with the femoral and tibial tunnels so as to add additional strength to the tissue graft. As will hereinafter be discussed, the folded section or loop <NUM> of tissue graft <NUM> will interface with femoral tunnel <NUM> and the two opposite ends (i.e., portion of graft bundles <NUM>) will be disposed in tibial tunnel <NUM>.

As seen in <FIG> and <FIG>, graft tow sutures <NUM> are looped around the folded portion or loop <NUM> of graft <NUM>, forming a strand of sutures that can be used to pull graft <NUM> into place. More particularly, the free ends of graft tow sutures <NUM> are passed through tibial tunnel <NUM> and femoral tunnel <NUM>, e.g., with the assistance of a suture passing guide wire (not shown) of the sort well known in the art. Once the free ends of graft tow sutures <NUM> have been passed through the tibial and femoral tunnels, the free ends of graft tow sutures <NUM> can be pulled so as to pull graft <NUM> into the tibial and femoral tunnels. <FIG> shows graft <NUM> folded over and in position to be pulled through tibial tunnel <NUM> and into femoral tunnel <NUM> using graft tow sutures <NUM>. The graft tow sutures <NUM> emanating from the distal end of femoral tunnel <NUM> are grasped with a clamp <NUM>, and clamp <NUM> and graft tow sutures <NUM> are used to pull graft <NUM> through tibial tunnel <NUM>, across the interior of the knee joint, and into femoral tunnel <NUM>.

Once tissue graft <NUM> is in place, the individual graft bundles <NUM> making up the aggregate tissue graft <NUM> may be manipulated to approximate the anatomic positions of the native ACL.

Advances in the research of ACL anatomy indicate that there are two primary bundles that make up the natural ACL, the anteromedial bundle and the posterolateral bundle. More particularly, and looking now at <FIG>, the anteromedial bundle <NUM> and the posterolateral bundle <NUM> are also referred to as the "AM" bundle and the "PL" bundle. The particular name of the ligament bundle refers to its point of origin on tibial plateau <NUM>, i.e., AM bundle <NUM> originates anteromedially and PL bundle <NUM> originates posterolaterally (relative to each other on the tibial plateau). As seen in <FIG>, the AM and PL bundles are roughly parallel to each other when the knee is in full extension.

However, when the knee is fully flexed, and looking now at <FIG>, AM bundle <NUM> and PL bundle <NUM> "cross" each other. As such, a true anatomic reconstruction of the ACL must place the graft bundles <NUM> into the proper femoral and tibial positions in order to achieve the natural kinematic motion of the ACL and the knee joint.

Thus, in an ACL reconstruction, it is desired to manipulate graft <NUM> into position such that the two graft bundles <NUM> (see <FIG> and <FIG>) making up the aggregate tissue graft <NUM> are located in the approximate positions of the natural AM and PL bundles of the native ACL. It has been demonstrated in biomechanical tests that this construct results in a more stable ACL reconstruction.

After graft <NUM> is inserted into the tibial and femoral tunnels, preferably with graft bundles <NUM> disposed so as to mimic the natural AM and PL bundles of the native ACL, fixation screws (also known as interference screws) are inserted into the femoral and tibial bone tunnels so as to secure graft <NUM> to femur <NUM> and tibia <NUM>. More particularly, and looking now at <FIG>, the femoral portion of graft <NUM> is first fixed into place by inserting a femoral interference screw <NUM> through the medial portal skin incision <NUM>, advancing femoral interference screw <NUM> across the interior of the joint, and then screwing femoral interference screw <NUM> into femoral tunnel <NUM> e.g., with a driver <NUM>. Femoral interference screw <NUM> squeezes graft <NUM> tightly against the wall of femoral tunnel <NUM>. As femoral interference screw <NUM> is tightened into place, the femoral interference screw creates an interference fit between femoral tunnel <NUM>, graft <NUM> and femoral interference screw <NUM>.

<FIG> shows the femoral fixation in place, with AM bundle 95AM of graft <NUM> approximating the anatomic position of the native AM bundle and PL bundle 95PL of graft <NUM> approximating the anatomic position of the native PL bundle.

Finally, and looking now at <FIG>, a tibial interference screw <NUM> is screwed into tibial tunnel <NUM> so as to secure graft <NUM> in tibial tunnel <NUM>.

The foregoing technique has been used for many years for the reconstruction of a damaged or injured ACL. This technique has generally been successful, but it does have some limitations. Typically, the location of graft <NUM> around the perimeter of interference screws <NUM>, <NUM> is uncontrolled because the graft bundles <NUM> rotate as the interference screws are inserted. As a result, it is difficult to set the interference screws while keeping AM bundle 95AM and PL bundle 95PL in their correct anatomical positions.

Furthermore, on the tibial side, tibial interference screw <NUM> may skive off the centerline of tibial tunnel <NUM> as tibial interference screw <NUM> is screwed into place. As a result, the AM and PL bundles 95AM, 95PL may bunch up and migrate to one side of tibial tunnel <NUM>. This occurrence creates a non-anatomic reconstruction which may also result in reduced pull-out strength and can contribute to changes in the natural motion of the knee. Clinically, this occurrence may contribute to tunnel widening where the tibial interference screw <NUM> skives off to one side of the tibial tunnel and the AM and PL bundles 95AM, 95PL are bunched up on the other side of the tibial tunnel, causing the softer cancellous bone inside the tibia to collapse. <FIG> illustrates how the off-center disposition of tibial interference screw <NUM> can result in a non-anatomic reconstruction: the AM and PL bundles 95AM, 95PL may not be located in their correct anatomic positions; at various degrees of knee flexion, one of the bundles may become excessively slack; the overall strength of the construct may be reduced; and natural knee motion may be altered, contributing to the development of osteoarthritis or an increase in the need for subsequent revision surgery.

A closer analysis of how the tibial and femoral tunnels <NUM>, <NUM> are formed, and a closer look at the anatomic insertions of graft <NUM> into the femur and tibia, illustrate how graft fixation can be configured to produce a more anatomic reconstruction.

Because cannulated drill <NUM> enters the surface of femur <NUM> at an angle (<FIG>), the entrance of femoral tunnel <NUM> is elliptical (<FIG>). This elliptical shape is not due to poorly manufactured drills, poor surgical technique, etc. It is the normal result of drilling a hole into a surface while the drill is set at a non-perpendicular angle to the surface. This is illustrated in <FIG>, which shows the outline of femoral tunnel <NUM> when looking directly into the bone surface.

Similarly, when cannulated drill <NUM> exits tibial tunnel <NUM> and enters the interior of the joint at an angle (<FIG>), the shape of the tunnel opening is elliptical at the tibial plateau <NUM> (<FIG>).

This elliptical shape of the joint-side entrance of femoral tunnel <NUM> and at the joint-side exit of tibial tunnel <NUM> has been documented in biomechanical studies.

For reference, the normal anatomic ACL insertion shape, or morphology, on the surface of the femur is shown in <FIG>. The AM and PL bundles <NUM>, <NUM> are shown in typical anatomic locations.

Similarly, the normal anatomic ACL insertion shape on the surface of the tibia are shown in <FIG>. The AM and PL bundles <NUM>, <NUM> are shown in typical anatomic locations.

Typical interference screws fixate graft <NUM> along the length of the interference screws, with the graft located between the interference screw and the side wall of the bone tunnel. See <FIG>, which shows femoral interference screw <NUM> securing graft <NUM> to femur <NUM>. However, as discussed above and as shown in <FIG>, the two graft bundles <NUM> of graft <NUM> do not typically lie in the true anatomic AM and PL bundle locations because graft bundles <NUM> rotate with the rotation of the interference screws before coming to rest in their final fixed position.

In a similar fashion, graft bundles <NUM> may rotate or be compressed into non-anatomic positions at the entrance of tibial tunnel <NUM>.

In addition, with respect to tibial fixation, the curved taper at the tip of an interference screw lies near the joint-side exit of tibial tunnel <NUM>, and this distal taper of the interference screw creates some laxity of graft <NUM>. <FIG> shows the AM graft bundle 95AM and the PL graft bundle 95PL shown approximately in their anatomic positions. The area at the distal end of interference screw <NUM> shows how graft <NUM> is loosely fixated in the area near the distal tip of the interference screw. This loose fixation of graft <NUM> may contribute to problems such as the so-called "windshield wiper effect", where graft <NUM> sweeps across the opening of the bone tunnel, thereby causing abrasion to the graft and to the bone tunnel; and joint laxity due to incomplete fixation of the graft into its anatomic position.

Thus there are problems with standard interference screw fixation: the graft bundles may come to rest around the interference screw in non-anatomic locations, resulting in a biomechanical construct that does not replicate the native anatomy; there is a lack of complete fixation of the graft at the opening of the bone tunnel to the joint space; and the unsecured graft in the elliptical opening of the bone tunnel may contribute to the windshield wiper effect, biomechanical instability and tunnel widening.

Another type of graft fixation in common use is sometimes referred to as suspensory fixation. In suspensory fixation, and looking now at <FIG>, graft <NUM> is passed through a fabric loop <NUM> which is, in turn, secured to a button <NUM>. Button <NUM>, loop <NUM> and graft <NUM> are inserted into a femoral bone tunnel <NUM>, and button <NUM> is "flipped" outside the distal bone cortex so as to suspend the graft in the femoral tunnel. In one variation of this technique, and as is shown in <FIG>, anatomic reconstruction is effected by creating two femoral bone tunnels <NUM>, one for the AM bundle 95AM and one for the PL bundle 95PL.

As also seen in <FIG>, a similar approach may be used on the tibial side.

Furthermore, if desired, and as is also shown in <FIG>, an interference screw <NUM> may also be used to enhance femoral or tibial fixation.

In this type of ligament reconstruction, the grafts <NUM> are freely suspended in the femoral tunnel(s) <NUM>. Micro-movement of graft <NUM> due to loading and unloading of the graft tissue may contribute to tunnel widening and loss of fixation. Also, the location of the graft bundles <NUM> in the femoral tunnel(s) is to some extent uncontrolled, inasmuch as the graft bundles are free to rotate and translate laterally, and to a smaller extent axially, within the femoral tunnel(s).

The previously-described approaches illustrate much of the current practice of ACL reconstruction. Current approaches do not lend themselves to creating a highly accurate anatomic reconstruction. The current devices can result in constructs that do not fully stabilize the graft. The subsequent motion of the graft may contribute to tunnel widening, loss of graft tension, loss of knee stability and may result in the need for subsequent revision surgery.

<CIT> discloses an apparatus for reconstructing a ligament, the apparatus comprising a fixation device for maintaining a graft ligament in a bone hole, the fixation device comprising a fixation screw comprising a body having screw threads formed thereon; and a ligament spacer mounted to the fixation screw, the ligament spacer comprising a canted face disposed opposite the fixation screw; such that the fixation screw and ligament spacer may be advanced into the bone hole with the graft ligament so that the fixation screw and the ligament spacer maintain the graft ligament within the bone hole and the canted face of the ligament spacer is aligned with the adjacent surface of the bone.

<CIT> discloses a material fixation system which is particularly adapted to improve the tendon- to-bone fixation of hamstring autografts, as well as other soft tissue ACL reconstruction techniques. The system is easy to use, requires no additional accessories, uses only a single drill hole, and can be implanted by one person. Additionally, it replicates the native ACL by compressing the tendons against the aperture of the tibial tunnel, which leads to a shorter graft and increased graft stiffness. It is adapted to accommodate single or double tendon bundle autografts or allografts.

<CIT> discloses anterior cruciate ligament reconstruction methods and devices are designed to achieve an anatomically accurate double bundle anterior cruciate ligament reconstruction by using a single femoral and tibial tunnel. The method and devices reconstruct the two bundles of the anterior cruciate ligament in a single femoral and tibial tunnel using a bone-patellar tendon-bone graft. The methods and devices enable an accurate anatomical reconstruction of the anteromedial and posterolateral bundles by creating a single femoral and tibial tunnel as opposed to creating two tunnels in the tibia and femur.

<CIT> discloses a curved wall fastener, the fastener comprising a curved wall surrounding an axial bore, the curved wall having a first end, a second end and a central portion connecting the first end and the second end, and a shaft configured to be pressed into the axial bore and cause at least a portion of the curved wall to move radially outward, wherein the curved wall is configured to remain at a fixed angle with respect to a longitudinal axis of the axial bore during the radially outward movement.

A new and improved approach for ACL reconstruction is disclosed herein. The object of the present invention is to secure the graft bundles to the femur and the tibia such that they are oriented and positioned in the true anatomic locations of the native ACL insertions. This orientation and positioning results in fixation of the graft AM bundle and the graft PL bundle near the natural anatomic footprints of the native AM bundle and native PL bundle at the tibia and femur. Furthermore, the graft AM bundle and the graft PL bundle are more effectively secured within the femoral and tibial bone tunnels, eliminating micro-movement within the bone tunnels.

According to the invention, a graft fixation device with the features of claim <NUM> is provided. Further aspects of the invention are defined in the dependent claims.

It is additionally here described a graft fixation device comprising:.

In another example there is provided a tibial graft separator for separating the AM bundle and PL bundle of an ACL graft for disposition in a notched tibial tunnel, wherein the notched tibial tunnel comprises a bore and a pair of diametrically-opposed notches opening on the bore and extending diametrically outboard of the bore, said tibial graft separator comprising:.

It is also here described femoral graft separator for separating the AM bundle and PL bundle of an ACL graft for disposition in a notched femoral tunnel, wherein the notched femoral tunnel comprises a bore and a pair of diametrically-opposed notches opening on the bore and extending diametrically outboard of the bore, said femoral graft separator comprising:.

In another example, it is described a femoral graft separator for separating the AM bundle and PL bundle of an ACL graft for disposition in a notched femoral tunnel, wherein the notched femoral tunnel comprises a bore and a pair of diametrically-opposed notches opening on the bore and extending diametrically outboard of the bore, said femoral graft separator comprising:.

It is also here described a method for securing a graft in a bone tunnel, wherein the graft comprises a first graft bundle and a second graft bundle, said method comprising:.

Further, it is here described a method for reconstructing a ligament, said method comprising:.

The features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein:.

In accordance with the disclosure, and looking now at <FIG>, the femoral tunnel is prepared by placing a femoral guide pin <NUM> into the anatomic location of the native femoral ACL insertion. It is desirable for femoral guide pin <NUM> to enter the intercondylar notch <NUM> at an angle, to avoid the adjacent medial condyle <NUM> as well as the tibial plateau <NUM>.

From a top view (<FIG>), with the knee in <NUM>° of flexion, the path of femoral guide pin <NUM> is shown as it passes by the medial condyle <NUM> and enters the medial aspect of the intercondylar notch <NUM>. Femoral guide pin <NUM> enters at an angle β from the sagittal plane. The angle β must be great enough to ensure that femoral guide pin <NUM> passes by the adjacent medial condyle <NUM> without contacting the medial condyle.

Placement of femoral guide pin <NUM> in this manner allows access to the true anatomic insertion point of the native ACL.

A cannulated drill <NUM> is then slid over femoral guide pin <NUM>, advanced through medial portal skin incision <NUM>, past the medial condyle <NUM> and tibial plateau <NUM> and into the anatomic location of the native femoral ACL insertion, as shown in <FIG>.

The femoral tunnel <NUM> is then drilled using cannulated drill <NUM> and the result is a circular bore hole with an elliptical tunnel entrance, as shown in <FIG>. This portion of the technique is generally similar to that which was discussed above, except that it is completed with an understanding that, as will hereinafter be discussed in further detail, the angled entrance of femoral tunnel <NUM> contributes in a positive manner in creating a more anatomic femoral fixation. As such, the surgeon does not try to "straighten out" the femoral tunnel so as to achieve a circular entrance, but rather may actually slightly increase the angle β so as to achieve the more anatomic elliptical entrance (i.e., to match the native anatomic insertion of the natural ACL on the femur).

Furthermore, it is helpful, when using the femoral fixation approach described below, to make certain adjustments to the drilling of the femoral tunnel. For one thing, the length of the femoral tunnel should be drilled <NUM>-<NUM> longer than the anticipated femoral fixation length. This allows for the graft to expand into the distal end of the femoral tunnel as the fixation squeezes the graft tightly up against the side wall of the femoral tunnel. Also, on the femoral side, it is useful to drill the tunnel <NUM>-<NUM> larger than the measured graft diameter.

Similarly, and looking now at <FIG>, the tibial tunnel is prepared by first drilling a tibial guide pin <NUM> (with the aid of a drill guide <NUM>) through the anteromedial surface of the tibia, exiting through the anatomic center of the desired ACL insertion on tibial plateau <NUM> (i.e., in the manner previously described). The tibial drilling angle, α<NUM>, can be smaller than the traditional tibial drilling angle α in a traditional ACL reconstruction, because the elliptical/oval nature of the tibial tunnel exit on the tibial plateau contributes to the anatomic reconstruction of the disclosure.

This can be a significant advantage over the prior art, since a shorter tibial tunnel (a consequence of drilling at angle α<NUM> rather than at angle α) means less trauma to the tibia and more space on the anteromedial surface of the tibia below the tibial tunnel (which may be used for other surgical procedures, if needed). Drill guide <NUM> is removed and a cannulated drill (not shown in <FIG>, but generally similar to cannulated drill <NUM> discussed above) is placed over tibial guide pin <NUM>. This cannulated drill is then drilled from the outside of the tibia through to the tibial plateau <NUM>, passing through the natural anatomic footprint of the native ACL insertion. <FIG> illustrates the effect of drilling at the angle α<NUM> (rather than at the conventional angle α) at the exit of the tibial tunnel onto tibial plateau <NUM>. The exit of tibial tunnel <NUM> onto tibial plateau <NUM> becomes a more elongated ellipse, increasing the footprint of the graft insertion and contributing to a more anatomic reconstruction, as will hereinafter be discussed in further detail.

It is here described a further unique step in the preparation of the femoral and tibial bone tunnels. More particularly, and looking now at <FIG>, after creating the anatomically-placed tibial and femoral tunnels <NUM>, <NUM>, each of the tunnels is "notched" (e.g., with two diametrically-opposed notches) using a notching instrument (or "notcher") <NUM> that is designed to closely and specifically match the pre-drilled tunnel while adding diametrically-opposed notches to the tunnel. These notches are placed at the natural bifurcation (split) locations of the AM and PL bundles 95AM, 95PL (i.e., the plane of the two diametrically-opposed notches is aligned with the natural bifurcation plane of the AM and PL bundles 95AM, 95PL). In the case of femoral tunnel <NUM>, femoral guide pin <NUM> is retained in the femur after the femoral tunnel drilling has been completed. Notcher <NUM> is cannulated. Notcher <NUM> is slid over the femoral guide pin <NUM> and brought into proximity with femoral tunnel <NUM>, as shown in <FIG>.

In one preferred form as seen in <FIG> and <FIG>, notcher <NUM> comprises a cylindrical tip <NUM> that closely matches the diameter of femoral tunnel <NUM>. Two stepped protrusions <NUM> emanate from opposing sides of cylindrical tip <NUM>, creating a form of broaching tool. The center opening (or cannulation) <NUM> of notcher <NUM> slides over femoral guide pin <NUM> so as to center notcher <NUM> in femoral tunnel <NUM>.

As seen in <FIG>, notcher <NUM> is driven into the femur, preferably to the depth of the drilled femoral bone tunnel, by hand or with a mallet, forming channels (or notches) <NUM> along the femoral bone tunnel <NUM>.

After notching the femoral tunnel, notcher <NUM> is removed from femoral guide pin <NUM> and then a smaller <NUM> to <NUM> cannulated drill <NUM> is passed over femoral guide pin <NUM> and drilled through the distal cortex of femur <NUM>. This extends the distal end of femoral tunnel <NUM> all the way through femur <NUM> for later use.

On the tibial side, similar notches are created for tibial tunnel <NUM>. However, in the absence of an emplaced tibial guide pin to support notcher <NUM> on the tibial side (i.e., tibial guide pin <NUM> is removed from the tibia after tibial tunnel <NUM> is formed, since there is no grounding for the distal end of tibial guide pin <NUM> after the tibial tunnel is drilled completely through to tibial plateau <NUM>), and considering the hardness of the cortical bone surface on the anteromedial surface of tibia <NUM>, two holes (see below) are drilled (using a tibial notcher drill guide and drill, see below) in the approximate area of the desired tibial notches and these two holes are then used to guide notcher <NUM> as the notches are formed in the tibia for tibial tunnel <NUM>.

The tibial notcher drill guide <NUM> and drill <NUM> are shown in <FIG>.

As seen in <FIG>, tibial notcher drill guide <NUM> is inserted into the previously-drilled tibial tunnel <NUM>. The two channels <NUM> (only one of which is seen in <FIG>) on the side of tibial notcher drill guide <NUM>, which connect with openings <NUM> formed on the proximal end of tibial notcher drill guide <NUM>, are aligned with the location of the desired anatomic split which is to be achieved between the AM and PL bundles. Drill <NUM> is then used to drill into one opening <NUM> and along channel <NUM> on one side of tibial notcher drill guide <NUM>, and to drill into the other opening <NUM> on the other side of tibial notcher drill guide <NUM> and along the channel <NUM> on the other side of tibial notcher drill guide <NUM>, thereby forming two side holes <NUM> (see <FIG>) which intersect with the larger tibial tunnel <NUM> and provide a guide for the stepped protrusions <NUM> of notcher <NUM> when notcher <NUM> is used to form notches in the tibial tunnel (see below). A larger threaded hole <NUM> (<FIG>) at the lower middle part of tibial notcher drill guide <NUM> may be used to secure a threaded tool to tibial notcher drill guide <NUM>, to aid in the insertion or removal of tibial notcher drill guide <NUM> from tibial tunnel <NUM>. <FIG> shows tibial notcher drill guide <NUM> in place and drill <NUM> about to make one of the side holes <NUM> for notcher <NUM>. Side holes <NUM> are preferably drilled through the tibia up to the subchondral bone, without entering the joint space.

The tibia, with tibial tunnel <NUM> and side holes <NUM> for receiving notcher <NUM>, is shown in <FIG>.

Then, and looking now at <FIG>, notcher <NUM> is brought into proximity with tibial tunnel <NUM>, the stepped protrusions <NUM> of notcher <NUM> are aligned with side holes <NUM> in the tibia, and the notcher is driven along the tibial tunnel, forming channels (or notches) <NUM> along the tibial tunnel, in a manner similar to the manner in which notches <NUM> were formed along the femoral tunnel. Notcher <NUM> is generally not driven all the way through the tibia and into the joint space, but is only driven up to the subchondral bone surface (i.e., notcher <NUM> is driven into tibia <NUM> to the same depth that the two side holes <NUM> are drilled into tibia <NUM>). This creates a subchondral bone surface at the distal ends of tibial notches <NUM> for the subsequently-placed tibial fixation device (see below) to rest on, thus increasing the strength of the tibial fixation.

<FIG> shows notcher <NUM> entering tibial tunnel <NUM> in order to create the tibial tunnel notches <NUM>.

The notched tibial tunnel (i.e., the tibial tunnel <NUM> with diametrically-opposed notches <NUM>) is shown in <FIG>.

After tibial tunnel <NUM> has been notched (i.e., by forming diametrically-opposed notches <NUM> along tibial tunnel <NUM>) and after femoral tunnel <NUM> has been notched (i.e., by forming diametrically-opposed notches <NUM> along femoral tunnel <NUM>), graft <NUM> is inserted through tibial tunnel <NUM> and into femoral tunnel <NUM>.

In a manner that is similar to the approach described above, graft <NUM> is folded over such that two graft bundles <NUM> comprise the aggregate graft <NUM>, and graft tow sutures <NUM> are looped around graft <NUM> at folded section <NUM> (i.e., where the graft is folded over).

Next, a guide pin (not shown), having an eyelet (not shown) for passing sutures, is inserted through medial portal skin incision <NUM>, through joint space <NUM> and through femoral tunnel <NUM>. The suture-carrying guide pin exits through the skin opposite the distal end of femoral tunnel <NUM>. The passing sutures carried through the femoral tunnel are then grasped (with a hemostat) and the guide pin is withdrawn. Then graspers (not shown) are inserted through tibial tunnel <NUM>, into joint space <NUM> and used to grasp the passing sutures emerging on the joint side of femoral tunnel <NUM>. These graspers are then used to pull the passing suture emerging from the joint side of femoral tunnel <NUM> across joint space <NUM> and down through tibial tunnel <NUM> until the passing sutures emerge on the anteromedial side of tibia <NUM>. At this point, these passing sutures extend from the anteromedial side of tibia <NUM>, up through tibial tunnel <NUM>, across joint space <NUM>, through femoral tunnel <NUM> and exits through the skin opposite the distal end of femoral tunnel <NUM>.

These passing sutures are then used to tow graft <NUM> through tibial tunnel <NUM>, through joint space <NUM> and into femoral tunnel <NUM>, i.e., by tying graft tow sutures <NUM> to the passing sutures emerging from tibial tunnel <NUM>, and then pulling on the passing sutures emerging from femoral tunnel <NUM>.

In order to ensure that graft bundles <NUM> of graft <NUM> are disposed in their anatomically correct locations within tibial tunnel <NUM> and femoral tunnel <NUM>, a tibial graft separator <NUM> (<FIG> and <FIG>) and a femoral graft separator <NUM> (<FIG> and <FIG>) are used.

As seen in <FIG> and <FIG>, tibial graft separator <NUM> is provided for aligning graft bundles <NUM> relative to tibial tunnel <NUM>. More particularly, tibial graft separator <NUM> comprises a rim <NUM> extending around the perimeter of tibial graft separator <NUM>. Tibial graft separator <NUM> is sized to fit into notches <NUM> formed in tibial tunnel <NUM>, with the tibial graft separator bifurcating tibial tunnel <NUM> into two passageways. The portion of tibial graft separator <NUM> which extends between rims <NUM> is thinner, providing spaces for allowing graft bundles <NUM> of graft <NUM> to pass through tibial tunnel <NUM> (the graft bundle 95AM being located on one side of the tibial graft separator and the graft bundle 95PL being located on the other side of the tibial graft separator). If desired, tibial graft separator <NUM> may include a label (e.g., "AM") on one side of tibial graft separator <NUM> in order to remind the surgeon of the AM bundle side, and tibial graft separator <NUM> may include another label (e.g., "PL") on the other side of tibial graft separator <NUM> in order to remind the surgeon of the PL bundle side. In one preferred form, tibial graft separator <NUM> comprises two small holes <NUM> for allowing temporary suture fixation of the graft <NUM> to tibial graft separator <NUM> (if necessary), and a larger hole <NUM> to aid in removing tibial graft separator <NUM> from tibial tunnel <NUM> (if necessary).

As seen in <FIG> and <FIG>, femoral graft separator <NUM> preferably comprises side protrusions <NUM> for tracking femoral graft separator <NUM> within notches <NUM> of femoral tunnel <NUM>, such that the femoral graft separator can bifurcate femoral tunnel <NUM> into two passageways. In one preferred form, femoral graft separator <NUM> is cannulated with a central bore <NUM>, whereby to permit passing femoral graft separator <NUM> over a guide wire if desired.

Looking now at <FIG>, after passing sutures have been extended from the anteromedial side of tibia <NUM>, through tibial tunnel <NUM>, across joint space <NUM> and through femoral tunnel <NUM>, tibial graft separator <NUM> is introduced between graft bundles <NUM>, and aligned with notches <NUM> of tibial tunnel <NUM>. Tibial graft separator <NUM> is placed between graft bundles <NUM> so that one of the graft bundles, 95AM, is in the position of the natural AM bundle and the other of the graft bundles, 95PL, is in the position of the natural PL bundle, with the sides of tibial graft separator <NUM> aligned with tibial tunnel notches <NUM>. Then, using the passing sutures secured to graft tow sutures <NUM>, and advancing tibial graft separator <NUM> in conjunction with graft <NUM>, graft <NUM> is pulled into tibial tunnel <NUM>. It will be appreciated that as graft <NUM> is pulled up through tibial tunnel <NUM>, the advancing tibial graft separator <NUM> will act as a tunnel bifurcator, ensuring that graft bundle 95AM is in the position of the natural AM bundle and the graft bundle 95PL is in the position of the natural PL bundle.

Still looking now at <FIG>, after the distal end of graft <NUM> has been drawn up through tibial tunnel <NUM> and into joint space <NUM>, a femoral guide wire <NUM> (approximately <NUM> to <NUM> in diameter) is passed through the loop <NUM> of graft <NUM>. AM and PL graft bundles 95AM, 95PL are then manipulated into their approximate native anatomic locations at the mouth of femoral tunnel <NUM>. Next, femoral graft separator <NUM> is advanced over femoral guide wire <NUM> so as to engage graft bundles 95AM, 95PL. Femoral graft separator <NUM> is then used to manipulate and push graft <NUM> into femoral tunnel <NUM>. As graft <NUM> is pushed into femoral tunnel <NUM>, femoral graft separator <NUM> keeps the AM and PL bundles 95AM, 95PL aligned and in their desired anatomic positions. The passing sutures and graft tow sutures <NUM> are then used to pull graft <NUM> up into femoral tunnel <NUM>, i.e., by pulling on the passing sutures emerging from the distal end of femoral tunnel <NUM>.

As a result of the foregoing, graft <NUM> will extend through tibial tunnel <NUM>, across joint space <NUM> and into femoral tunnel <NUM>, with the AM and PL bundles 95AM, 95PL aligned and in their desired anatomic positions.

In an alternative approach, and looking now at <FIG>, the soft tissue graft <NUM> is prepared differently than previously described. Cadaveric evaluations and engineering tests have indicated this alternative method to be the preferred method of graft preparation when utilizing the new fixation device and technique. The folded-over length of graft <NUM> should measure <NUM> on each side of the fold (<NUM> between the central whipstitched sections, when graft <NUM> is laid out end-to-end). Graft <NUM> is whipstitched with one color suture on one leg (i.e., one bundle <NUM>) of the graft, and a second color suture on the other leg (i.e., the other bundle <NUM>) of the graft. An additional suture, an anatomic guide wire passing suture <NUM>, is passed through the loop <NUM> of graft <NUM>, or pushed through the midsubstance of the graft via blunt dissection.

Looking now at <FIG>, graft <NUM> is towed into the tibial tunnel and then into the femoral tunnel, preferably by first positioning passing sutures from the anteromedial side of tibia <NUM>, up through tibial tunnel <NUM>, across joint space <NUM>, through femoral tunnel <NUM> and out the skin opposite the distal end of femoral tunnel <NUM> in the manner previously described, attaching the graft tow sutures <NUM> to the passing sutures, and then pulling on the passing sutures emerging from the distal end of femoral tunnel <NUM> to draw graft <NUM> up into tibial tunnel <NUM> and across joint space <NUM> until the graft just enters the joint space. Again, tibial graft separator <NUM> is inserted into tibial tunnel <NUM> along with graft <NUM>, separating the AM and PL bundles 95AM, 95PL from one another as they extend through tibial tunnel <NUM>. The anatomic guide wire passing suture <NUM> is kept easily accessible near the lateral side of the graft. The AM bundle 95AM should be "on top of' tibial graft separator <NUM> and the PL bundle 95PL should be "on the underside of" tibial graft separator <NUM>.

The passing sutures and/or graft tow sutures <NUM> are then further pulled so as to advance graft <NUM> to the mouth of femoral tunnel <NUM>. With the knee in <NUM>° of flexion, as is the typical surgical position, AM bundle 95AM is positioned near the posterior portion of femoral tunnel <NUM>. The PL bundle 95PL is positioned near the anterior portion of femoral tunnel <NUM>. Guide wire passing suture <NUM> is then used to pull a femoral guide wire <NUM> through the loop <NUM> in graft <NUM> (i.e., between the AM bundle 95AM and the PL bundle 95PL), or through the midsubstance of both graft bundles 95AM, 95PL together, and then through femoral tunnel <NUM>. More particularly, and as seen in <FIG>, <FIG> and <FIG>, this is preferably done by advancing forceps (not shown) through medial portal skin incision <NUM>; picking up guide wire passing suture <NUM> with the forceps; pulling guide wire passing suture <NUM> out medial portal skin incision <NUM>; engaging a guide wire suture <NUM> (which is threaded through the eyelet <NUM> of femoral guide wire <NUM>); drawing guide wire suture <NUM> back through medial portal skin incision <NUM>, across joint space <NUM>, and through femoral tunnel <NUM>; and then using guide wire suture <NUM> to pull femoral guide wire <NUM> through medial portal skin incision <NUM>, across joint space <NUM>, through the loop <NUM> in graft <NUM> (i.e., between the AM bundle 95AM and the PL bundle 95PL) and through femoral tunnel <NUM>. Note that guide wire suture <NUM> and femoral guide wire <NUM> are positioned such that they are in front of (i.e., anterior to) the AM bundle 95AM to aid in the anatomic arrangement of the graft bundles. Note also that as the graft <NUM> is pulled into position, tibial graft separator <NUM> keeps the graft bundles 95AM, 95PL aligned in their respective AM and PL positions.

As seen in <FIG>, femoral guide wire <NUM> is rounded at its distal tip to prevent damage to the graft bundles 95AM, 95PL, but generally tapered to allow ease of passage through the graft bundles and the femoral tunnel. Femoral guide wire <NUM> is preferably flat on both sides (i.e., it has a generally rectangular cross-section with rounded sides) for later use during the insertion of the femoral fixation device and, if desired, the tibial fixation device (see below). Eyelet <NUM> is on the leading tip of femoral guide wire <NUM> to allow it to accept guide wire suture <NUM>, which is used to pull femoral guide wire <NUM> into femoral tunnel <NUM>.

Graft <NUM> is then pulled slightly into the mouth of femoral tunnel <NUM> (i.e., by pulling distally on the passing sutures and/or graft tow sutures <NUM>) and then retracted slightly to create a slight amount of slack in the graft. At this point, a cannulated femoral graft inserter <NUM> (see <FIG>) is used to assist insertion of graft <NUM> into femoral tunnel <NUM>. Cannulated femoral graft inserter <NUM> comprises a body <NUM> and two legs, i.e., a lower leg <NUM> and an upper leg <NUM>.

More particularly, femoral graft inserter <NUM> is used to keep graft bundles 95AM, 95PL separated while graft <NUM> is pulled into femoral tunnel <NUM>. Femoral graft inserter <NUM> is first introduced through the medial portal skin incision <NUM>, being careful to avoid catching soft tissue. Femoral graft inserter <NUM> is passed over femoral guide wire <NUM> to guide it up to the mouth of femoral tunnel <NUM>. The lower leg <NUM> of femoral graft inserter <NUM> is hooked around the PL graft bundle 95PL. The legs <NUM>, <NUM> of femoral graft inserter <NUM> are inserted slightly into the notches <NUM> already formed in femur <NUM>. Graft <NUM> is then pulled into femoral tunnel <NUM>. Note that the AM and PL bundles 95AM, 95PL are positioned by femoral graft inserter <NUM> into their respective AM and PL positions as graft <NUM> is pulled into femoral tunnel <NUM>, whereby to mirror the natural anatomic positions of the AM and PL bundles of the native ACL.

Graft <NUM> is then ready to be fixated into place with novel femoral and tibial fixation devices, i.e., a femoral fixation device <NUM> (<FIG>) and a tibial fixation device <NUM> (<FIG>).

Looking now at <FIG>, <FIG>, femoral fixation device <NUM> comprises two components. The first component (<FIG>) consists of a femoral fixation screw <NUM> with a necked down region <NUM> at its distal tip and a reduced-diameter proximal head (or drive end) <NUM>. Femoral fixation screw <NUM> provides graft fixation as it is screwed into femoral tunnel <NUM>. Femoral fixation screw <NUM> tapers or curves to a narrow distal end to facilitate starting and insertion into the femoral tunnel. Also, femoral fixation screw <NUM> is cannulated to allow the use of femoral guide wire <NUM> (see above) to guide the femoral fixation screw straight into the femoral tunnel. A hex socket, hexalobe socket, square socket or other shaped socket <NUM> resides at the proximal end of femoral fixation screw <NUM> for engagement by an appropriate insertion (tightening) tool (i.e., a driver).

The second component of femoral fixation device <NUM> is a femoral graft spacer <NUM> (<FIG>). Femoral graft spacer <NUM> has a distal end <NUM> having an opening <NUM> and a proximal end <NUM> having an opening <NUM>. Guide ribs <NUM> extend between distal end <NUM> and proximal end <NUM>. Proximal end <NUM> may be formed flat as shown in <FIG> or, in the preferred embodiment, and as shown in <FIG>, the proximal end <NUM> may be configured at an angle so as to form an elliptical face to more closely match the femoral bone surface at the joint side mouth of femoral tunnel <NUM>. Guide ribs <NUM> may have multiple barbs <NUM> as shown in <FIG>, or a stepped feature <NUM> as shown in <FIG>, to grip onto the side wall of femoral notches <NUM> and improve holding strength. Femoral graft spacer <NUM> has an internal cavity <NUM> sized to receive femoral fixation screw <NUM>.

The purpose of femoral graft spacer <NUM> is to spread and separate the AM and PL bundles 95AM, 95PL as femoral fixation screw <NUM> is tightened into place in femoral tunnel <NUM>. Furthermore, femoral graft spacer <NUM> helps direct femoral fixation device <NUM> straight into femoral tunnel <NUM> by virtue of guide ribs <NUM> which track in the previously-created femoral notches <NUM>. Femoral fixation screw <NUM> and femoral graft spacer <NUM> are assembled together (see below) so that the two components can rotate independently of one another, thus allowing femoral graft spacer <NUM> to track in femoral notches <NUM> and maintain alignment of the graft bundles 95AM, 95PL while femoral fixation screw <NUM> is tightened so as to secure the graft ligament on the femoral tunnel. The angled proximal end <NUM> of femoral graft spacer <NUM> aligns to the bony surface of the femur at the joint side mouth of the femoral tunnel such that the bony defect in the femur is filled and the graft is supported around the elliptical mouth of the femoral tunnel. The angled proximal end <NUM> of femoral graft spacer <NUM> may be formed or manufactured in a variety of angles or shapes to best match the anatomy of the femur. Note that the angled proximal end <NUM> of femoral graft spacer <NUM> corresponds to the angle β and closely approximates the contour of the mouth of femoral tunnel <NUM>.

Femoral fixation screw <NUM> and femoral graft spacer <NUM> are assembled together by capturing the femoral fixation screw within cavity <NUM> of femoral graft spacer <NUM>. This may be done by deforming femoral graft spacer <NUM> and snapping it over femoral fixation screw <NUM>. More particularly, to assemble the two components together, the femoral graft spacer <NUM> is aligned along the side of the femoral fixation screw <NUM> as shown in <FIG>. The proximal head <NUM> of the femoral fixation screw <NUM> is then inserted into the opening <NUM> of the proximal end <NUM> of femoral graft spacer <NUM> as shown in <FIG>. The distal tip of the femoral graft spacer <NUM> is then snapped over the distal tip of the femoral fixation screw <NUM> so that distal tip <NUM> of femoral fixation screw <NUM> is received in opening <NUM> in the distal end <NUM> of femoral graft spacer <NUM>, whereby to complete assembly of the two components. Note that when femoral fixation screw <NUM> and femoral graft spacer <NUM> are assembled together in this manner, femoral fixation screw <NUM> is free to rotate relative to femoral graft spacer <NUM>.

The cross-sectional view in <FIG> illustrates femoral graft spacer <NUM> assembled onto femoral fixation screw <NUM>. There is an angled surface <NUM> on the inside of femoral graft spacer <NUM> that allows femoral fixation screw <NUM> to be partially inserted into the femoral graft spacer prior to snapping the components into place. The femoral fixation screw is then supported on both ends of the femoral graft spacer (i.e., by engagement of the distal end <NUM> of femoral fixation screw <NUM> in opening <NUM> of femoral graft spacer <NUM>, and by engagement of the proximal end <NUM> of femoral fixation screw <NUM> in opening <NUM> of femoral graft spacer <NUM>), and can rotate freely relative to the femoral graft spacer.

Femoral graft spacer <NUM> functions as a means to align and separate the graft bundles 95AM, 95PL in femoral tunnel <NUM> and to fill the bony defect. Femoral graft spacer <NUM> can be positioned to spread the graft bundles 95AM, 95PL into their correct anatomic positions, regardless of the rotational position of femoral fixation screw <NUM>. Also, femoral graft spacer <NUM> may function as a "strain relief", allowing the tension in graft <NUM> to be spread over the entire length of femoral fixation device <NUM>.

Femoral fixation screw <NUM> and femoral graft spacer <NUM> may be made from metal, plastic (e.g., PEEK) and/or a bioabsorbable material.

The end view shown in <FIG> illustrates the contoured outer wall <NUM> of femoral graft spacer <NUM> for graft seating. The contoured outer wall <NUM> cooperates with guide ribs <NUM> to define graft recesses to engage with, and provide alignment of, the graft bundles 95AM, 95PL. Note that femoral fixation screw <NUM> extends radially outboard of contoured outer wall <NUM> of femoral graft spacer <NUM>. The shape of contoured outer wall <NUM> may be a variety of shapes to allow space for the graft strands. Guide ribs <NUM> that span the length of femoral graft spacer <NUM> are fit into the notches <NUM> previously formed in femoral tunnel <NUM>. In addition to guiding femoral fixation device <NUM> along femoral tunnel <NUM>, guide ribs <NUM> separate the graft bundles 95AM, 95PL and organize them onto one side or the other of femoral fixation device <NUM>.

Femoral graft spacer <NUM> has smooth radii around critical corners to ensure strain-relieved fixation of the graft bundles. As femoral fixation device <NUM> is advanced along femoral tunnel <NUM>, guide ribs <NUM> glide into notches <NUM> of femoral tunnel <NUM> and center femoral graft spacer <NUM> onto the elliptical entrance of femoral tunnel <NUM>, thus separating the graft bundles 95AM, 95PL into their anatomically correct AM and PL locations.

Proximal end <NUM> of femoral graft spacer <NUM> is angled (approximately equal to β) to create the mating elliptical, oval shape needed to fill the elliptical, oval-shaped joint-side entrance of femoral tunnel <NUM>. The angled shape of the proximal end of the femoral graft spacer fills the femoral tunnel entrance and urges the graft up against the tunnel entrance so as to mimic the wider anatomic footprint of the natural femoral insertion. The side view of the femoral fixation device is shown in <FIG>, illustrating the angle β.

Looking now at <FIG>, which is a top view, femoral graft spacer <NUM> includes a tapered lead-in surface <NUM> that helps start the femoral graft spacer into femoral tunnel <NUM> and tunnel notches <NUM>.

The lead tip <NUM> of femoral graft spacer <NUM> has a slot <NUM> that can be engaged with femoral guide wire <NUM>. See <FIG> and <FIG>.

Femoral guide wire <NUM> is used to guide the femoral fixation device <NUM> to the femoral tunnel and to rotate the femoral fixation device <NUM> as needed so that the femoral fixation device is properly oriented with respect to the graft bundles 95AM, 95PL and with respect to the notches <NUM> in the femoral tunnel <NUM>. A guide wire dial <NUM> (<FIG>) slips over the distal end of femoral guide wire <NUM>, with a slot <NUM> on guide wire dial <NUM> engaging with flats <NUM> on femoral guide wire <NUM>, and is rotated so as to properly orient femoral fixation device <NUM> with respect to graft bundles 95AM, 95PL and femoral notches <NUM>.

The AM and PL bundles 95AM, 95PL separate from each other on opposite sides of femoral graft spacer <NUM> as femoral fixation device <NUM> begins to engage with the femoral tunnel <NUM> (<FIG>). The AM and PL bundles 95AM, 95PL may be further manipulated, or spread out, with one bundle on each side of femoral fixation device <NUM>. The graft bundles 95AM, 95PL then align with, and fit in between, the recesses between the bone tunnel <NUM> and the femoral fixation device <NUM>. See <FIG> showing the femoral fixation device <NUM> with its guide ribs <NUM> aligned with notches <NUM>.

Femoral fixation device <NUM> is then fully advanced into femoral tunnel <NUM>, i.e., by using a driver <NUM> to turn femoral fixation screw <NUM>, which causes the threads of the femoral fixation screw to engage graft <NUM> and the side walls of femoral tunnel <NUM> and thereby advance femoral fixation device <NUM> up the femoral tunnel. As femoral fixation device <NUM> advances up femoral tunnel <NUM>, femoral fixation device <NUM> creates an interference fit between the femoral fixation device, the graft and the side walls of femoral tunnel <NUM>. Note that as femoral fixation device <NUM> advances within femoral tunnel <NUM>, tunnel notches <NUM> act as tracks for guide ribs <NUM> of femoral fixation device <NUM>, keeping the fixation centered in the femoral tunnel and maintaining separation of graft bundles 95AM, 95PL. When femoral fixation device <NUM> is fully seated in femoral tunnel <NUM>, the canted or angled surface <NUM> of the femoral graft spacer is approximately flush, or even with, the bone surface adjacent the joint-side mouth of femoral tunnel <NUM>.

In the completed femoral ligament construct, the femoral fixation device <NUM> is seated approximately flush with the joint-side mouth of the femoral tunnel <NUM>. The graft is fixated between the femoral fixation screw threads and the femoral tunnel. <FIG> shows a cross-section through the axis of the femoral fixation device that is perpendicular to the guide ribs <NUM> of the femoral graft spacer. <FIG> illustrates how the graft is pressed between the femoral fixation screw and the side wall of the femoral tunnel and the graft fibers are interspersed between the threads of the femoral fixation screw. The graft exits the femoral tunnel in the area of the recesses of the femoral graft spacer, with the AM and PL bundles 95AM, 95PL separated into their correct anatomic positions.

The femoral fixation device <NUM> provides significant advantages in femoral graft fixation:.

Tibial fixation is effected using a tibial fixation device <NUM> which is generally similar to the aforementioned femoral fixation device <NUM>. Tibial fixation device <NUM> comprises a tibial graft spacer <NUM> and a tibial fixation screw <NUM>.

Looking now at <FIG>, tibial graft spacer <NUM> has a distal end <NUM> having an opening <NUM>, and a proximal end <NUM> having an opening <NUM>. Guide ribs <NUM> extend between distal end <NUM> and proximal end <NUM> of tibial graft spacer <NUM>. Tibial graft spacer <NUM> has an internal cavity <NUM> sized to receive tibial fixation screw <NUM>, as will hereinafter be discussed in greater detail. It should be appreciated that tibial graft spacer <NUM> is generally similar to femoral graft spacer <NUM> previously discussed, and shares a number of common features. These common features include an angled surface <NUM> whereby to provide an elliptical shape (but disposed on the distal end of the tibial graft spacer <NUM>, rather than on the proximal end as is the case with the femoral graft spacer <NUM>), tapered lead-in surfaces <NUM> to aid insertion into the tibial tunnel, a contoured outer wall <NUM> for fixating the graft in the tibial tunnel, a slot <NUM> at the distal tip of distal end <NUM> of the tibial graft spacer <NUM> for, optionally, engaging with flats on a guide wire, and cannulation through the center of the tibial graft spacer (and its associated tibial fixation screw) for receiving a guide wire. If desired, guide ribs <NUM> can also include one or more barbs and/or one or more stepped features (analogous to barbs <NUM> and stepped feature <NUM> of femoral graft spacer <NUM>) to grip onto the side wall of tibial notches <NUM> and improve holding strength.

Tibial fixation screw <NUM> is shown in <FIG>. Tibial fixation screw <NUM> has a necked down region <NUM> at its distal tip and a reduced-diameter proximal head (or drive end) <NUM>. Tibial fixation screw <NUM> tapers or curves to a narrow distal end to facilitate starting and insertion into the tibial tunnel. With the present invention, tibial fixation screw <NUM> may be the same design as femoral fixation screw <NUM>, but may be made in different lengths (i.e., <NUM> - <NUM> longer) in order to utilize more of the tibial tunnel, which is typically longer than the femoral tunnel (in which case tibial graft spacer <NUM> has its length correspondingly adjusted).

Tibial fixation device <NUM> is shown in cross-section in <FIG>. The angle α<NUM> is shown at the angled surface <NUM> at the distal tip of tibial fixation device <NUM>.

<FIG> illustrates tibial graft spacer <NUM> and the tibial fixation screw <NUM> in assembled form, whereby to form the complete tibial fixation device <NUM>. It will be appreciated that tibial graft spacer <NUM> and tibial fixation screw <NUM> are assembled together in substantially the same manner as femoral graft spacer <NUM> and femoral fixation screw <NUM> are assembled, i.e., by snapping tibial fixation screw <NUM> into cavity <NUM> formed in tibial graft spacer <NUM> (i.e., by deforming tibial graft spacer <NUM> and snapping it over tibial fixation screw <NUM>). More particularly, to assemble the two components together, the tibial graft spacer <NUM> is preferably aligned along the side of tibial fixation screw <NUM>. The proximal head (or drive end) <NUM> of tibial fixation screw <NUM> is inserted into opening <NUM> of the proximal end <NUM> of tibial graft spacer <NUM>. The distal tip of tibial graft spacer <NUM> is then snapped over the distal tip of tibial fixation screw <NUM> so that the distal tip <NUM> of tibial fixation screw <NUM> is received in opening <NUM> in the distal end of tibial graft spacer <NUM>, whereby to complete assembly of the two components. It will also be appreciated that when tibial graft spacer <NUM> and tibial fixation screw <NUM> are assembled together in the foregoing manner, tibial fixation screw <NUM> will be free to rotate relative to tibial graft spacer <NUM>.

The angle α<NUM> at the distal tip of tibial fixation device <NUM> corresponds to the angle resulting from the tibial tunnel drilling technique discussed above. The angled surface <NUM> at angle α<NUM> creates a close anatomic alignment between the bone surface (i.e., tibial plateau <NUM>) and tibial fixation device <NUM>, and also secures the graft bundles 95AM, 95PL in their proper anatomic positions.

Similar to the femoral fixation device <NUM>, the tibial fixation device <NUM> preferably has the aforementioned contoured outer wall <NUM> which cooperates with guide ribs <NUM> to define graft recesses on the top and bottom sides of the tibial graft spacer to engage with, and provide alignment of, graft bundles 95AM, 95PL, whereby to urge graft bundles 95AM, 95PL into their anatomic positions. See <FIG>, viewed from the distal tip of tibial fixation device <NUM>. The recesses shown are preferably crescent-shaped (i.e., the same shape as the recesses of femoral graft spacer <NUM>), although the recesses could have some other shape if desired.

Tibial graft spacer <NUM> is sized relative to tibial fixation screw <NUM>. In one preferred form of the present invention, the graft recesses of tibial graft spacer <NUM> are smaller in size than tibial fixation screw <NUM>. Guide ribs <NUM> of the tibial graft spacer <NUM> are larger than the screw diameter for alignment and graft bundle separation.

Guide ribs <NUM> that span the length of tibial graft spacer <NUM> are fit into notches <NUM> previously formed in tibial tunnel <NUM>. In addition to guiding tibial fixation device <NUM> along tibial tunnel <NUM>, guide ribs <NUM> separate the graft bundles 95AM, 95PL and organize them onto one side or the other of tibial fixation device <NUM>. It should be appreciated that tibial graft spacer <NUM> can be positioned to spread the graft bundles 95AM, 95PL into their correct anatomic position, regardless of the rotational disposition of tibial fixation screw <NUM>.

Tibial fixation screw <NUM> and tibial graft spacer <NUM> may be made from metal, plastic (e.g., PEEK) and/or a bioabsorbable material.

In the final step of the ligament reconstruction, tibial fixation device <NUM> is advanced into tibial tunnel <NUM> using a driver <NUM>. <FIG> shows driver <NUM>, tibial fixation device <NUM> and the notched tibial tunnel <NUM>. The graft is omitted from <FIG> in order to illustrate the alignment of the tibial fixation device <NUM> and the tibial tunnel <NUM>. Tibial fixation device <NUM> is preferably advanced into tibial tunnel <NUM> in the following manner. Tibial graft separator <NUM> is removed from tibial tunnel <NUM>. Tibial fixation device <NUM>, manipulated by driver <NUM>, is advanced between graft bundles 95AM, 95PL, brought to the anteromedial mouth of tibial tunnel <NUM>, has its guide ribs <NUM> aligned with tunnel notches <NUM>, and tibial fixation screw <NUM> is turned with driver <NUM>, causing tibial fixation device <NUM> to advance along tibial tunnel <NUM>, creating an interference fit between tibial fixation device <NUM>, graft bundles 95AM, 95PL and the side wall of tibial tunnel <NUM>. Note that as tibial fixation device <NUM> is advanced up tibial tunnel <NUM>, guide ribs <NUM> of tibial fixation device <NUM> orient and separate the graft bundles 95AM, 95PL into their anatomically correct AM and PL locations. If desired, tibial fixation device <NUM> can be set using driver <NUM> alone (as shown in <FIG>) or, if desired, tibial fixation device <NUM> and driver <NUM> can be tracked over a guide wire (which may be a guidewire such as guidewire <NUM> having flats <NUM>) so that the guidewire can be used to rotate tibial fixation device <NUM> to a desired angular disposition (i.e., to line up with tibial notches <NUM> and separate graft bundles 95AM, 95PL).

In the case of tibial fixation device <NUM>, the strength of the construct is enhanced by driving the fixation into the tibial tunnel until distal end <NUM> of tibial graft spacer <NUM> contacts the subchondral bone at the distal end of tibial notches <NUM> (which terminate proximal of tibial plateau <NUM>). See <FIG> which is a cross-sectional view through the axis of tibial fixation device <NUM>, in the central plane of guide ribs <NUM> of tibial graft spacer <NUM>. As noted above, during the preparation of the tibial tunnel, notcher <NUM> is preferably driven up to the subchondral bone but then stopped, leaving a shelf for the distal end of tibial fixation device <NUM> to rest against. Tension in graft <NUM> pulls tibial fixation device <NUM> against the subchondral bone shelf. The combination of strong aperture fixation and the resistance of tibial fixation device <NUM> against the subchondral shelf creates a very strong tibial ligament construct (i.e., a very strong fixation of graft <NUM> to tibia <NUM>). As tibial fixation device <NUM> advances up tibial tunnel <NUM>, tibial fixation device <NUM> creates an interference fit between the tibial fixation device <NUM>, graft <NUM> and the side walls of tibial tunnel <NUM>, in the same manner as with the femoral fixation device. Furthermore, the fibers of graft <NUM> lodge between the screw threads of tibial fixation screw <NUM> in a manner similar to that of femoral fixation device <NUM>, contributing to the strong aperture fixation.

<FIG> shows femoral fixation device <NUM> and tibial fixation device <NUM> secured in their respective positions within femoral tunnel <NUM> and tibial tunnel <NUM>, respectively. Both femoral fixation device <NUM> and tibial fixation device <NUM> lie approximately flush with the bone surfaces surrounding the mouths of their respective bone tunnels on the inside of the knee joint (i.e., with angled surface <NUM> of femoral graft spacer <NUM> disposed at the proximal end of femoral tunnel <NUM> proximate joint space <NUM>, and with angled surface <NUM> of tibial graft spacer <NUM> disposed at the distal end of tibial tunnel <NUM> proximate joint space <NUM>). Guide ribs <NUM> of femoral graft spacer <NUM> lie within femoral notches <NUM>, and guide ribs <NUM> of tibial graft spacer <NUM> lie within tibial notches <NUM>, providing definitive passageways for the AM and PL bundles 95AM, 95PL.

The finished construct, showing the AM and PL bundles 95AM, 95PL in position, is shown in <FIG>.

Tibial fixation device <NUM> provides significant advantages in tibial graft fixation:.

The foregoing discussion describes the preferred embodiments of femoral fixation device <NUM> and tibial fixation device <NUM> and and their preferred method of use. However, if desired, alternative constructions may be utilized with the present invention.

By way of example but not limitation, femoral fixation device <NUM> and/or tibial fixation device <NUM> may be modified to permit the components to be manufactured using other methods such as injection molding. <FIG> illustrate design modifications to tibial fixation device <NUM> that may permit injection molding. The proximal opening <NUM> of tibial graft spacer <NUM> is formed as a tapered slot or hole <NUM>, such that the opening does not form an undercut surface for the purpose of molding. The taper still permits assembly of tibial fixation screw <NUM> inside of tibial graft spacer <NUM>, as described above. Tibial fixation screw <NUM> may have a deeper, tapered drive recess <NUM> (formed by an alternate polygon, such as the five-sided polygon shown) formed in reduced diameter proximal head (or drive end) <NUM> of tibial fixation screw <NUM>. This would provide more surface area to distribute drive forces, which can be an important consideration where the component is molded from plastic.

Similar changes may be made to the femoral fixation device <NUM>.

Additionally, small protrusions <NUM> (<FIG>) may extend from the distal end of the femoral graft spacer <NUM>. These protrusions capture a graft between the end of femoral fixation device <NUM> and the far end of the femoral tunnel, as may be commonly used in tenodesis procedures of the biceps tendon, or other soft tissue connections.

In another version of the present invention, the guide ribs <NUM> of the femoral graft spacer <NUM> may not be symmetric, but positioned asymmetrically about the femoral fixation screw. This can be useful when the graft is closely compressed on the narrow side, and more spread out on the broader side. It may also be useful when a bone block graft is to be positioned on one side.

Similar changes may be made to the tibial fixation device.

In another version of the present invention, and looking now at <FIG>, femoral graft spacer <NUM> may be formed with a single guide rib <NUM> positioned symmetrically or asymmetrically about femoral fixation screw <NUM>. This can be useful when the entirety of the graft is intended to be secured in one area. This may also be useful when a bone block graft is to be positioned on one side.

It should be understood that many additional changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention, as defined by the appended claims.

Methods for securing a graft in a bone tunnel are described here below.

A first method for securing a graft in a bone tunnel, wherein the graft comprises a first graft bundle and a second graft bundle is described, said method comprising: forming a notched bone tunnel comprising a bore and a pair of.

The method described above may further comprise:
providing a graft fixation device comprising:.

It is also described a method for reconstructing a ligament, said method comprising:.

Claim 1:
A graft fixation device (<NUM>) comprising:
a graft separator (<NUM>) comprising a distal end (<NUM>), a proximal end (<NUM>), a cavity (<NUM>) disposed between said distal (<NUM>) end and said proximal end (<NUM>), and at least one guide rib (<NUM>) disposed radially outboard of said cavity (<NUM>) and extending between said distal end (<NUM>) and said proximal end (<NUM>); and
an interference screw (<NUM>) rotatably mountable within said cavity (<NUM>), said interference screw (<NUM>) comprising a distal end (<NUM>), a proximal end (<NUM>), and a screw thread disposed intermediate thereof, said screw thread disposed radially outboard of at least a portion of said graft separator (<NUM>) and radially inboard of said at least one guide rib (<NUM>);
said distal end (<NUM>) of said graft separator (<NUM>) comprising a distal hole (<NUM>), said proximal end (<NUM>) of said graft separator (<NUM>) comprising a proximal hole (<NUM>), said distal end (<NUM>) of said interference screw (<NUM>) comprising a distal projection, and wherein said distal projection of said interference screw (<NUM>) is rotatably receivable within said distal hole (<NUM>) of said graft separator (<NUM>);
characterized in that said proximal end (<NUM>) of said interference screw (<NUM>) comprises a proximal projection, and further wherein said proximal projection of said interference screw (<NUM>) is rotatably receivable within said proximal hole (<NUM>) of said graft separator (<NUM>), whereby to rotatably mount said interference screw (<NUM>) within said cavity (<NUM>).