Suture anchoring system and method

A suture anchoring system and method includes a plurality of anchor members interconnected to form an anchor assembly with a suture extending therefrom. The anchor assembly has an insertion configuration wherein the anchor members are aligned in a substantially linear arrangement for delivery through an aperture in bodily tissue and an expanded configuration wherein the anchor members are transitioned to a non-linear arrangement to prevent passage of the anchor assembly back through the aperture.

BACKGROUND

The complete or partial detachment of ligaments, tendons or other soft tissues from their associated bones within the body is a relatively common place injury, particularly among athletes and physically active individuals. These types of injuries generally result from excessive stresses being applied to the soft tissues. For example, a tissue detaching injury may occur as the result of a fall, overexertion during a work-related activity, during the course of an athletic event, and/or in association with other situations or physical activities.

In the case of a partial detachment injury, which is commonly referred to under the general term “sprain”, the injury will frequently heal itself if given sufficient time and if care is taken not to expose the injury to any undue or extraordinary stress during the healing process. If, however, the ligament or tendon is completely detached from its associated bone or bones, or if it is severed as a result of a traumatic injury, partial or permanent disability may result. Fortunately, a number of surgical techniques exist for reattaching detached tissues and/or completely replacing severely damaged tissues. One such technique involves reattachment of detached tissue using traditional attachment devices such as metal staples, sutures over buttons and/or cancellous bone screws. These types of traditional attachment techniques and devices may also be used to attach tendon or ligament substitutes (sometimes formed of autogenous tissue harvested from other locations in the body) to the desired bone or bones.

Although attempts have been made to provide techniques and devices for forming an attachment to bone or other tissue, there is a general need in the industry to provide an improved suture anchoring system and method. The present invention satisfies this need and provides other benefits and advantages in a novel and unobvious manner.

SUMMARY

The present invention relates generally to an improved suture anchoring system and method. While the actual nature of the invention covered herein can only be determined with reference to the claims appended hereto, certain forms of the invention that are characteristic of the preferred embodiments disclosed herein are described briefly as follows.

In one form of the present invention, a suture anchoring system is provided including at least three anchor members interconnected to form an anchor assembly with a suture extending therefrom. The anchor assembly has an insertion configuration sized for delivery through an aperture in bodily tissue and is transitionable to an expanded configuration sized to prevent passage of the anchor assembly back through the aperture.

In another form of the present invention, a suture anchoring system is provided including at least three anchor members interconnected to form an anchor assembly with a suture extending therefrom. The anchor assembly has an insertion configuration wherein the anchor members are aligned in a substantially linear arrangement for delivery through an aperture in bodily tissue and an expanded configuration wherein the anchor members are transitioned to a non-linear arrangement to prevent passage of the anchor assembly back through the aperture.

In another form of the present invention, a suture anchoring system is provided including at least three anchor members interconnected to form an anchor assembly with a suture extending therefrom. The anchor assembly includes first and second outer anchor members and at least one intermediate anchor member, and has an insertion configuration wherein the anchor members are aligned in a substantially linear arrangement for delivery through an aperture in bodily tissue and an expanded configuration wherein the outer anchor members are drawn toward one another to define a non-linear arrangement to prevent passage of the anchor assembly back through the aperture.

In another form of the present invention, a suture anchoring system is provided including at least three anchor members, means for interconnecting the anchor members to form an anchor assembly with a suture extending therefrom and having an insertion configuration wherein the anchor members are aligned in a substantially linear arrangement for delivery through an aperture in bodily tissue, and means for transitioning the anchor assembly from the insertion configuration to an expanded configuration wherein the anchor members are transitioned to a non-linear arrangement to prevent passage of the anchor assembly back through the aperture.

In another form of the present invention, a suture anchoring system is provided including a plurality of anchor members interconnected to form an anchor assembly with a suture extending therefrom. The anchor assembly has an insertion configuration wherein the anchor members are aligned in a substantially linear arrangement for delivery through an aperture in bodily tissue and an expanded configuration wherein first and second ones of the anchor members are drawn toward one another to define a non-linear arrangement to prevent passage of the anchor assembly back through the aperture. The system further includes an actuating element extending through a first loop structure associated with the first anchor member and through a second loop structure associated with the second anchor member, and wherein the first and second anchor members are drawn toward one another by pulling the actuating element in a direction away from the anchor assembly to at least partially transition the anchor assembly toward the expanded configuration.

In another form of the present invention, a method for anchoring a suture to bodily tissue is provided including providing at least three anchor members interconnected to form an anchor assembly with a suture extending from the anchor assembly, aligning the anchor members in a substantially linear configuration, inserting the anchor members through an aperture in the bodily tissue while in the linear configuration, and transitioning the anchor members from the linear configuration to a non-linear configuration to prevent passage of the anchor assembly back through the aperture.

It is one object of the present invention to provide an improved suture anchoring system and method. Further objects, features, advantages, benefits, and aspects of the present invention will become apparent from the drawings and description contained herein.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIG. 1, shown therein is a suture anchoring system10according to one form of the present invention. The anchoring system10is generally comprised of a plurality of anchor members12and a number of suture elements14. As will be discussed in greater detail below, in one embodiment of the invention, the anchoring system10is configured for anchoring to either hard or soft biological tissue, with the suture elements14serving to attach another element or structure (either biological or non-biological) to the biological tissue. As used herein, the term “suture” is broadly defined to include any type of longitudinal element suitable for attachment to biological tissue including, for example, thread, wire, gut or any other type of suture material known to those of skill in the art.

In the illustrated embodiment of the invention, the anchor members12each have a generally tubular configuration including a cylindrical wall20and defining an axial passage or channel22extending therethrough. However, it should be understood that other shapes and configurations of the anchor members12are also contemplated as falling within the scope of the present invention including, for example, a rectangular, triangular, polygonal or spherical configuration, or any other suitable shape or configuration. The anchor members12are preferably formed of a bio-compatible material. In one embodiment, the anchor members12are formed of metallic material such as stainless steel or a stainless steel alloy, titanium or a titanium alloy, a shape-memory alloy, or any other suitable metallic material. However, the use of other materials is also contemplated, including polymeric or ceramic materials, resorbable materials, bioabsorbable materials, or bone or bone substitute materials.

In the illustrated embodiment of the invention, the suture anchoring system10includes four anchor members12a,12b,12cand12dthat are coupled together or interconnected to form an anchor assembly. However, it should be understood that the anchoring system10may include any number of anchor members12, including two, three or five or more anchor members. In one embodiment, the anchor members12a-12dare coupled or interconnected to one another via a linking element30. In the illustrated embodiment, the linking element30comprises a suture extending through the axial passages22in each of the anchor members12a-12dto link the anchor members12a-12dtogether in series. The linking element30provides structural integrity to the anchoring system10by controlling the position and/or orientation of the anchor members12a-12drelative to one another, the details of which will be discussed below. Additionally, the linking element30has a length l such that the anchor members12a-12dmay be axially separated or spaced from one another in a non-abutting manner, the purpose of which will also become apparent below.

In the illustrated embodiment of the invention, the ends30a,30bof the linking element30are attached to one another so to define a continuous suture loop having a first end loop32extending from the outer anchor member12aand a second end loop34extending from the outer anchor member12d. In the illustrated embodiment of the invention, the ends30a,30bare tied or knotted together to form the suture loop30. However, it should be understood that the ends30a,30bof the suture loop30may be attached to one another using other techniques such as, for example, via the use of a crimp or another type of coupling device, by fusing or splicing the ends30a,30btogether, or by any other suitable method of attachment. It should also be understood that the linking element30need necessarily be configured as a loop, but may alternatively define a non-looped, single strand configuration. It should further be understood that the anchor members12a-12dneed not necessarily be coupled together or interconnected via a single suture element, but may alternatively be individually coupled together via a number of discrete suture elements. Additionally, it should be understood that the anchor members12a-12dneed not necessarily be coupled together by suture material, but may alternatively be coupled together using other elements and techniques such as, for example, via a number of pins, hinges, fittings, eyelets or any other suitable coupling device.

In the illustrated embodiment of the invention, the anchoring system10also includes an actuating element40that cooperates with the linking element30to selectively manipulate the position and/or orientation of one or more of the anchor members12a-12d. In the illustrated embodiment, the actuating element40comprises a suture that engages the end portions of the linking element30to selectively manipulate the position and/or orientation of one or more of the anchor members12a-12d. In a specific embodiment, the actuating element40extends through the end loops32,34of the linking element30such that pulling the ends40a,40bof the actuating element40draws the outer anchor members12a,12dtoward one another and transitions one or more of the anchor members12a-12dto a different position and/or orientation, the details of which will be discussed below. Although the actuating element40is illustrated and described as being engaged with the end loops32,34of the linking element30, it should be understood that the actuating element40may alternatively be coupled to the outer anchor members12a,12dvia other suitable techniques for drawing the outer anchor members12a,12dtoward one another and for selectively transitioning one or more of the anchor members12a-12dto a different position and/or orientation. For example, a full or partial loop element may be attached directly to the outer anchor members12a,12dthrough which the actuating element40extends.

In the illustrated embodiment of the invention, the anchoring system10further includes a second actuating element50that cooperates with the linking element30to selectively manipulate the position and/or orientation of one or more of the anchor members12a-12d. In the illustrated embodiment, the actuating element50comprises a suture that engages the linking element30at a location between the inner anchor member12b,12cto selectively manipulate the position and/or orientation of one or more of the anchor members12a-12d. In one embodiment, the actuating element50is looped about the linking element30such that pulling the ends50a,50bof the actuating element50draws the inner anchor members12b,12cto a location between the outer anchor members12a,12d. In a specific embodiment, the actuating element50is threaded between the strands of the suture loop linking element30. Although the actuating element50is illustrated and described as being looped about the linking element30, it should be understood that the actuating element50may be coupled to the linking element30via other techniques suitable for drawing the inner anchor members12b,12cbetween the outer anchor members12a,12d. For example, instead of looping the actuating element50about the linking element30, an end portion of the actuating element50may by tied or otherwise secured to the linking element30.

Having illustrated and described the various elements and features associated with the suture anchoring system10, reference will now be made to a technique for engaging the anchoring system10to human body tissue. As indicated above, the anchoring system10is used to anchor a suture in either hard or soft biological tissue. In the illustrated embodiment of the invention, the anchoring system10is used to anchor a suture to bone in a human body. In a specific embodiment, the anchoring system10is used to anchor a suture to a portion of one or more vertebrae in the spinal column. However, it should be understood that other applications of the anchoring system10are also contemplated, including anchoring to other bones or anatomic structures within the human body. Additionally, it should be understood that use of the anchoring system10in other animals is also contemplated as falling within the scope of the present invention.

Referring toFIG. 2, the anchoring system10is illustrated as being used in association with a bone B having a relatively hard and compact outer cortical layer L surrounding a softer and more porous inner cancellous region C. In one embodiment of the invention, an axial tunnel or aperture A having a maximum transverse dimension d may be preformed through the cortical layer L and into the cancellous region C for receiving the anchoring system10. However, in an alternative embodiment, the anchoring system10may be inserted directly into the body tissue without creating a preformed tunnel or aperture, particularly in applications involving relatively soft body tissue.

In the illustrated embodiment of the invention, the anchoring system10is delivered to the surgical site via a delivery instrument200extending along a longitudinal axis201and generally comprising an outer sleeve or cannula member202and an inner rod member204. The cannula member202defines an axial passageway206extending therethrough and having an inner cross section sized somewhat larger than the outer transverse cross section of the individual anchor members12. The inner rod member204is sized and configured to be slidably positioned within the axial passageway206of the cannula member202. In one embodiment, the inner rod member204has a circular outer cross section that corresponds to the inner cross section of the cannula member202. However, other configurations of the cannula member202and/or the inner rod member204are also contemplated as falling within the scope of the present invention.

The outer transverse cross section of the individual anchor members12is sized somewhat smaller than the inner cross section of the axial passageway206in the cannula member202to allow the anchor members12to freely slide along the axial passageway206. Additionally, sufficient clearance exists between the anchor members12and the cannula member202to provide spacing for the passage of the suture elements40and50. In the illustrated embodiment, the axial passageway206has a circular inner cross section corresponding to the circular outer cross section of the anchor members12. However, it should be understood that the axial passageway206may be configured to have a different inner cross section such as, for example, a rectangular, triangular or polygonal inner cross section, or any other inner cross section suitable for receiving and conveying the anchor members12therethrough. Additionally, in an alternative embodiment of the invention, the outer transverse cross section of the anchor members12and the inner cross section of the axial passageway206can be configured different from one another to provide a predetermined spacing therebetween for passage of the suture elements40and50. For example, in one alternative embodiment, the axial passageway206can be configured to have a circular inner cross section whereas the anchor members12can be configured to have a generally triangular or rectangular outer cross section.

The anchor members12a-12dare initially positioned within the distal end portion of the cannula member202in an axially-aligned or linear configuration, with the axes of the anchor members12a-12dgenerally aligned along the longitudinal axis201. The end portions40a,40band50a,50bof the suture elements40and50extend from the proximal end (not shown) of the cannula member202for subsequent manipulation by the surgeon. The distal end portion202aof the cannula member202is positioned proximally adjacent the bone B, with the axial passageway206generally aligned with the aperture A. However, in an alternative embodiment of the invention, the distal end portion202aof the cannula member202may be positioned within the aperture A formed through the outer cortical layer L and possibly extending partially into the cancellous region C of the bone B.

Referring toFIG. 3, once the cannula member202is properly positioned relative to the aperture A, the inner rod member204is axially displaced in the direction of arrow210with the distal end204aengaging the anchor member12d, which in turn displaces the anchor members12a-12dthrough the axial passageway206. The inner rod member204is axially advanced in the direction of arrow210until the anchor members12a-12dare deployed from the cannula member202and into the aperture A in the cancellous region C of the bone B. As illustrated inFIG. 3, the depth of the aperture A in the cancellous region C is preferably sized to entirely receive the anchor members12a-12dtherein in the axially-aligned configuration. The rod member204may then be removed from the cannula member202or can remain in position until the anchoring process is completed to prevent the anchor members12a-12dfrom passing back through the cortical layer L of the bone B.

Referring toFIG. 4, once the anchor members12a-12dare deployed from the cannula member202and properly positioned within the aperture A in the cancellous region C of the bone B, the anchor members12a-12dare selectively transitioned to a non-linear or expanded configuration. As should be appreciated, transitioning of the anchor members12a-12dto the non-linear configuration results in outward compression against the relatively soft cancellous bone tissue, thereby resulting in enlargement of the aperture A in the bone B. However, as should also be appreciated, for applications involving anchoring to denser or harder bone tissue, an enlarged portion of the aperture A may have to be preformed in the bone B to allow for transitioning of the anchor members12a-12dto the expanded, non-linear configuration.

Transitioning of the anchor members12a-12dis effectuated by pulling the ends40a,40bof the actuating suture element40in a proximal direction so as to reconfigure the anchor members12a-12dfrom the axially-aligned configuration illustrated inFIG. 3to the expanded configuration illustrated inFIG. 4. More specifically, since the suture element40extends through the end loops32,34of the linking element30, pulling the suture element40in a proximal direction draws the outer anchor members12a,12dtoward one another. As a result, the anchor members12a-12dare repositioned/reoriented so as to define a generally U-shaped configuration, with the anchor members12a,12bbeing arranged generally laterally opposite the anchor members12c,12d.

Once transitioned to the non-linear configuration illustrated inFIG. 4, the anchor members12a-12dare further transitioned to the expanded configuration illustrated inFIG. 5by pulling the ends50a,50bof the actuating suture element50in a proximal direction. As should be appreciated, pulling the suture element50in a proximal direction reconfigures the anchor members12a-12dfrom the U-shaped expanded configuration illustrated inFIG. 4to the denser configuration illustrated inFIG. 5. Pulling the actuating element50in a proximal direction draws the inner anchor members12b,12cbetween the outer anchor members12a,12d. More specifically, the inner anchor members12b,12care repositioned and reoriented relative to the outer anchor members12a,12dso as to position the inner anchor members12b-12cin a laterally adjacent or side-by-side relationship relative to the outer anchor members12a,12d. As should be appreciated, the expanded configuration of the anchor members12a-12dillustrated inFIG. 5is somewhat larger than the inner cross section of the aperture A extending through the outer cortical layer L of the bone B. Accordingly, the expanded configuration of the anchor members12a-12dwill not pass through the aperture A in the cortical bone layer L, thereby securely anchoring the anchor members12a-12dand the suture elements40and50to the bone B. The suture elements40and50may then be attached to other elements/structures so as to secure such elements/structures to the bone B, examples of which will be set forth below.

Referring toFIG. 6, shown therein is a suture anchoring system100according to another form of the present invention. The anchoring system100is generally comprised of a plurality of anchor members112and a number of suture elements114. As will be discussed in greater detail below, in one embodiment of the invention, the anchoring system100is configured for anchoring to either hard or soft biological tissue, with the suture elements114serving to attach another element or structure (either biological or non-biological) to the biological tissue.

In the illustrated embodiment of the invention, the anchor members112are configured identical to the anchor members12illustrated and described above with regard to the anchoring system10, with each anchor member112having a generally tubular configuration including a cylindrical wall120and defining an axial passage or channel122extending therethrough. However, it should be understood that other shapes and configurations of the anchor members112are also contemplated as falling within the scope of the present invention including, for example, a rectangular, triangular, polygonal or spherical configuration, or any other suitable shape or configuration. The anchor members112are preferably formed of a bio-compatible material. In one embodiment, the anchor members112are formed of metallic material such as stainless steel or a stainless steel alloy, titanium or a titanium alloy, a shape-memory alloy, or any other suitable metallic material. However, the use of other materials is also contemplated, including polymeric or ceramic materials, resorbable materials, bioabsorbable materials, or bone or bone substitute materials.

In the illustrated embodiment of the invention, the suture anchoring system100includes three anchor members112a,112band112cthat are coupled together or interconnected to form an anchor assembly. However, it should be understood that the anchoring system100may include any number of anchor members112, including two or four or more anchor members. In one embodiment, the anchor members112a-112care coupled or interconnected to one another via a linking element130. In the illustrated embodiment, the linking element130comprises a suture extending through the axial passages122in each of the anchor members112a-112cto link the anchor members112a-112ctogether in series. The linking element130provides structural integrity to the anchoring system100by controlling the position and/or orientation of the anchor members112a-112crelative to one another, the details of which will be discussed below. Additionally, the linking element130has a length l′ such that the anchor members112a-112cmay be axially separated or spaced from one another in a non-abutting manner, the purpose of which will become apparent below.

In the illustrated embodiment of the invention, the ends130a,130bof the linking element130are attached to one another so to define a continuous suture loop having a first end loop132extending from the outer anchor member112aand a second end loop134extending from the outer anchor member112c. In the illustrated embodiment of the invention, the ends130a,130bare tied or knotted together to form the suture loop130. However, it should be understood that the ends130a,130bof the suture loop130may be attached to one another using other techniques such as, for example, via the use of a crimp or another type of coupling device, by fusing or splicing the ends130a,130btogether, or by any other suitable method of attachment. It should also be understood that the linking element130need necessarily be configured as a loop, but may alternatively define a non-looped, single strand configuration. It should further be understood that the anchor members112a-112cneed not necessarily be coupled together or interconnected via a single suture element, but may alternatively be individually coupled together via a number of discrete suture elements. Additionally, it should be understood that the anchor members112a-112cneed not necessarily be coupled together by suture material, but may alternatively be coupled together using other elements and techniques such as, for example, via a number of pins, hinges, fittings, eyelets or any other suitable coupling device.

In the illustrated embodiment of the invention, the anchoring system100also includes an actuating element140that cooperates with the linking element130to selectively manipulate the position and/or orientation of one or more of the anchor members112a-112c. In the illustrated embodiment, the actuating element140comprises a suture that engages the end portions of the linking element130to selectively manipulate the position and/or orientation of one or more of the anchor members112a-112c. In a specific embodiment, the actuating element140extends through the end loops132,134of the linking element130such that pulling the ends140a,140bof the actuating element140draws the outer anchor members112a,112ctoward one another and transitions one or more of the anchor members112a-112cto a different position and/or orientation, the details of which will be discussed below. Although the actuating element140is illustrated and described as being connected to the end loops of the linking element130, it should be understood that the actuating element140may be coupled to the outer anchor members112a,112cvia other suitable techniques for drawing the outer anchor members112a,112ctoward one another and for selectively transitioning one or more of the anchor members112a-112cto a different position and/or orientation. For example, a full or partial loop element may be attached directly to the outer anchor members112a,112cthrough which the actuating element140extends.

Having illustrated and described the various elements and features associated with the suture anchoring system100, reference will now be made to a technique for engaging the anchoring system100to biological tissue such as, for example, to the bone B. However, as discussed above with regard to the anchoring system10, it should be understood that other applications of the anchoring system100are also contemplated, including anchoring to other bones or anatomic structures. Referring toFIG. 7, in one embodiment of the invention, the anchoring system100is delivered to the surgical site via the delivery instrument200illustrated and described above. The anchor members112a-112care initially positioned within the distal end portion of the cannula member202in an axially-aligned or linear configuration, with the axes of the anchor members112a-112cgenerally aligned along the longitudinal axis201. The end portions140a,140bof the suture element40extend from the proximal end (not shown) of the cannula member202for subsequent manipulation by the surgeon. The distal end portion202aof the cannula member202is positioned proximally adjacent the bone B, with the axial passageway206generally aligned with the aperture A extending into the cortical layer L.

Referring toFIG. 8, once the cannula member202is properly positioned relative to the aperture A, the inner rod member204is axially displaced in the direction of arrow210with the distal end204aengaging the anchor member112c, which in turn displaces the anchor members112a-112cthrough the axial passageway206. The inner rod member204is axially advanced in the direction of arrow210until the anchor members112a-112care deployed from the distal end202aof cannula member202and into the cancellous region C of the bone B. As illustrated inFIG. 8, the depth of the aperture A in the cancellous region C is preferably sized so as to receive the axially-aligned anchor members112a-112ctherein. The rod member204may then be removed from the cannula member202or can remain in position until the anchoring process is completed to prevent the anchor members112a-112cfrom passing back through the cortical layer L of the bone B.

Referring toFIG. 9, once the anchor members112a-112care deployed from the distal end of the cannula member202and properly positioned within the aperture A in the cancellous region C of the bone B, the anchor members112a-112care transitioned to a non-linear or expanded configuration. Such transitioning is effectuated by pulling the ends140a,140bof the actuating suture element140in a proximal direction to reconfigure the anchor members112a-112cfrom the axially-aligned configuration illustrated inFIG. 8to the expanded configuration illustrated inFIG. 9. More specifically, since the suture element140extends through the end loops132,134of the linking element130, pulling the suture element140in a proximal direction draws the outer anchor members112a,112ctoward one another. As a result, the anchor members112a-112care repositioned/reoriented so as to define a generally triangular-shaped configuration, with the outer anchor members112a,112cbeing angled toward one another and with the inner anchor member112bextending laterally between the outer anchor members112a,1112c.

As should be appreciated, the expanded configuration of the anchor members112a-112cillustrated inFIG. 9is larger than the inner cross section of the aperture A extending through the outer cortical bone layer L. Accordingly, the expanded configuration of the anchor members112a-112cwill not pass through the aperture A in the cortical bone layer L, thereby securely anchoring the anchor members112a-112cand the suture element140to the bone B. The suture element140may be attached to other elements/structures so as to secure such elements/structures to the bone B.

As should now be appreciated, the anchoring systems10,100illustrated and described above may be anchored to either hard or soft biological tissue, with the suture elements40,50and140being used to attach another element or structure to the biological tissue. In one embodiment of the invention, the anchoring systems10,100may be used to provide a surgical anchor useful in the repair and/or replacement of ligaments, tendons or other types of tissues. In another embodiment of the invention, the anchoring systems10,100may be used to provide a surgical anchor for holding a bone block in place in a tunnel formed in bone such that a piece of soft tissue attached to the bone block can be connected to the bone under tension. In yet another embodiment of the invention, the anchoring systems10,100may be used to provide a surgical anchor that avoids or reduces the risks associated with severing, twisting or otherwise damaging material associated with soft tissue repair or replacement. In still another embodiment of the invention, the anchoring systems10,100may be used to provide a surgical anchor that may be inserted into a tunnel formed in bone that avoids or reduces the likelihood of seriously damaging the surrounding bone material. In a further embodiment of the invention, the anchoring systems10,100may be used to provide a surgical anchor that is adapted to secure material used in association with tissue repair or replacement in close proximity to bone in such a manner as to promote the formation or growth of a permanent attachment therebetween. In another embodiment of the invention, the anchoring systems10,100may be used in association with a method for repairing and/or replacing ligaments, tendons or other types of tissues by coupling an end portion of such tissue (or its replacement) to a tunnel extending into or through a bone or a bone-like structure.