Soft tissue rivet and method of use

A method and apparatus for reattaching soft tissue to a selected boney structure using a rivet. Generally, a rivet having first portion and a second portion is provided to fully secure a soft tissue in the boney structure. The first portion of the rivet retains the soft tissue via a suture which is threaded through the first portion. The second portion of the rivet has at least one expanding member which engages the boney structure upon contact with the first portion of the rivet. Thus, the soft tissue is fully secured to the boney structure, ensuring proper healing.

FIELD

The present invention relates generally to structures and methods for repairing soft tissue, and particularly to a method and apparatus for a soft tissue rivet.

BACKGROUND

Various procedures may be performed to repair soft tissue in the body. For example, tendons that attach muscle to bone or ligaments that attach bones to other bones may need to be repaired or replaced for various reasons. Specifically, an injury to a ligament in the leg for example, may require the ligament to be replaced. Alternatively, a tendon from a muscle may simply be loosened from its attachment point and need to be reattached without the necessity of a replacement.

Generally, it is known to fix the soft tissue to a selected area on the bone by providing a suture through a selected portion of the soft tissue while securing the other end of the suture to a selected area on the bone. Various structures and methods, such as soft tissue suture anchors, can be provided to anchor or hold the suture in the selected bone area. Typical soft tissue suture anchors may require the placement of the soft tissue suture anchor into the bone prior to the engagement of the soft tissue with the suture anchor. This procedure may be time consuming and require precise placement. Therefore, it may be desirable to provide a soft tissue attachment mechanism that may substantially simplify the reattachment or replacement of soft tissue during a surgical procedure.

SUMMARY

A method and apparatus for reattaching soft tissue to a pre-selected boney structure using an assembly, such as a rivet. A rivet may have a first portion and a second portion that is provided to fully secure a soft tissue in the boney structure. The first portion of the rivet retains the soft tissue via a suture which is threaded through the first portion. The second portion of the rivet has at least one expanding member that may engage the boney structure or portion upon contact with the first portion of the rivet. Thus, the soft tissue is fully secured to the boney structure, ensuring proper healing.

A device for attaching soft tissue to a pre-selected area of a boney structure is provided. The device has a bullet operable to receive a suture to engage the soft tissue and a sleeve operable to retain the bullet in the pre-selected area of boney structure via at least one expanding member. A guide pin slideably engaged with the bullet and the sleeve is operable to engage the sleeve with the bullet. The soft tissue may be attached to the device prior to insertion in the boney structure.

A device for attaching soft tissue to a pre-selected area of a boney structure including a first portion operable to retain a section of the soft tissue is provided. The device may further include a second portion operable to retain the first portion in the pre-selected area of boney structure via an expanding member. A guide pin is slideably engaged with the first portion and the second portion and extends beyond the first portion to pierce the soft tissue prior to the insertion of the soft tissue in the boney structure.

A method for attaching a soft tissue to a pre-selected area of a boney structure including forming a cavity in the boney structure for receipt of an anchor assembly is provided. The soft tissue may be coupled to a first portion of the anchor assembly and the first portion of the anchor assembly may be disposed in the cavity. A second portion of the anchor assembly is pushed along a guide pin to secure the first portion of the anchor assembly in the cavity.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

The following description of various embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. Although the following description is related generally to a soft tissue anchor or rivet that can be positioned in a pre-drilled hole, that is a hole provided in a boney structure for acceptance of the soft tissue rivet. It will be understood that a soft tissue rivet including an impacting tip or self-drilling thread may be provided as well. Moreover, it will be understood that the soft tissue rivet, as described and claimed herein, can be used with any appropriate surgical procedure. Also, an anchor or rivet will be understood to refer to any appropriate assembly or device for anchoring a portion to a boney structure. Moreover, the anchor need not be positioned only in a boney structure. Therefore, it will be understood that the following discussions is not intended to limit the scope of the appended claims.

With reference toFIGS. 1 and 3, a soft tissue rivet or anchor assembly10is illustrated. The rivet10may be operable with a guide pin12to secure a soft tissue portion14in a pre-drilled hole16in a boney structure18. The rivet10may include a first portion or bullet20and a second portion or sleeve22. Briefly, the bullet20may be provided to engage and position a soft tissue portion in a first instance. The bullet20may also interact with the sleeve22to hold the soft tissue in a selected position. It will be understood the bullet20may be any member that may be able to interact with the sleeve22, or any appropriate member, to position a soft tissue portion in a selected manner. The bullet20and the sleeve22are merely exemplary and not intended to be limiting.

With continuing reference toFIGS. 1 and 3and additional reference toFIGS. 2 and 4, the bullet20includes a generally cup-shaped section24at a distal end26and a tapered section28at a proximal end30. The cup-shaped section24is generally displaced from the tapered section28via a stepped portion29formed in the bullet20. The bullet20may further include a bore32which extends through the cup-shaped section24and tapered section28for receipt of the guide pin12therethrough. The bullet20may be molded from a resorbable material, such as, for example, Lactosorb®, however, it will be understood that other types of biocompatible materials and other methods of forming could be used. For example, the bullet20may be formed of other polymers or of metal portions.

The cup-shaped section24may be configured for receipt of the soft tissue14. The cup-shaped section24may define a diameter D1which is generally the largest diameter of the bullet20. The cup-shaped section24has a surface34which abuts the soft tissue14when the rivet10is fully secured in the boney structure18, as will be described in greater detail below. The bullet20further includes a pair of formed eyelets36for receipt of flexible member or strand38, such as a suture, therethrough. The eyelets36may be formed along a side37of the bullet20, as shown inFIGS. 3 and 4, or may be formed transverse on the bullet20, as shown inFIG. 3A. The flexible strand38secures the soft tissue14to the surface34of the cup-shaped section24. Although the cup-shaped section24is described herein as being cup-shaped, it will be understood that other shapes could be used depending on the particular soft tissue configuration, such as, for example, box-shaped. The cup-shaped section24may also be formed of a deformable material to substantially mold to the soft tissue in site. Further, the cup-shaped section24may include at least one or multiple projections39, as illustrated inFIG. 1A, to further secure the soft tissue (not shown) to the cup-shaped section24.

With reference back toFIGS. 1,2,3and4, the tapered section28of the bullet20may include a first shoulder40, second shoulder42and a third shoulder44adjacent to an end portion46. The first shoulder40is separated from the cup-shaped section24by a tapered area41and has a diameter D2that is generally smaller than the diameter D1of the cup-shaped section24. The first shoulder40is coupled to the second shoulder42by a cylindrical section48. The second shoulder42is coupled to the third shoulder44by a tapered area50. The diameter D2of the first shoulder40is generally greater than a diameter D3of the second shoulder42. A diameter D4of the third shoulder44is generally smaller than the diameter D3of the second shoulder42, such that the second shoulder42and third shoulder44form a generally tapered section which ends at the first shoulder40. The end portion46of the tapered section28has a diameter D5which is generally equal to the diameter D4of the third shoulder44.

It will be understood, however, that only appropriate configuration may be provided to extend from the distal end28of the bullet20. As described herein, the bullet20interacts with the second portion22and any configuration may be provided for such an interaction. The end portion46further includes at least one grip surface52to couple the bullet20to the sleeve22. The grip surface52may include an annular protrusion54, and in this exemplary embodiment, the end portion46includes three annular protrusions54having a diameter D6which interact or mate with the sleeve22. Although this embodiment includes three annular protrusions54, it will be understood that the grip surface52could be configured in any manner that may assist in coupling or interconnecting the bullet20to the sleeve22, such as, for example, barbs. The shape of the tapered section28from the first shoulder40to the end portion46defines a surface for mating the bullet20with the sleeve22as will be described in greater detail below.

The tapered section28may also include a pair of formed flanges56having a thickness T spaced about a centerline C of the bullet20. The flanges56are generally triangular and extend a length L from the cup-shaped section24to the third shoulder44of the tapered section28. The flanges56may provide a locating point for an instrument58. The instrument58is removably coupled to the bullet20to insert the bullet20with the attached soft tissue14into the pre-drilled hole16in the boney structure18.

The instrument58may be cylindrical in shape with a body60coupled to a handle portion62. The body60is further coupled to an attachment section64for receipt of the flanges56from the bullet20therein. Specifically, the attachment section64has a first cupped flange66and a second cupped flange68separated by a slot70. The first and second cupped flanges66,68have an interior surface72that is configured to slideably engage the tapered section28of the bullet20. The instrument58may further define a throughbore74for receipt of the guide pin12therethrough.

The guide pin12is configured to slideably engage the throughbore74of the instrument58when the instrument58is attached to the bullet20. The guide pin12extends through the bore32of the bullet20and may extend beyond the cup-shaped section24to pierce the soft tissue14. The guide pin12may also include a stepped portion75to engage the cup-shaped section24, as will be discussed in greater detail below. The guide pin12can be made of any suitable biocompatible corrosive resistant material, such as, for example, surgical steel and may be a K-wire or other appropriate member. In this regard, the guide pin12need not be made of the same material as the bullet20. In addition, the guide pin12is configured to slideably engage the sleeve22. The slideable engagement of the guide pin12with the sleeve22facilitates the engagement of the sleeve22with the bullet20.

The sleeve22includes a throughbore76to allow the guide pin12therethrough. The sleeve22is typically made from a resorbable material, such as, for example, Lactosorb®, however other suitable materials could be employed such as other polymers or metals. The sleeve22may include one or a plurality of expanding members78defined or separated by a slot80in an annular body82. The annular body82may further include formed eyelets83for receipt of a suture38therethrough to couple the soft tissue14to the sleeve22, as shown inFIG. 3A. With reference back toFIGS. 1,2,3and4, the expanding members78are hingedly coupled to the annular body82to enable the expanding members78to move and secure the sleeve22in the pre-drilled hole14. More specifically, the throughbore76has a first diameter D10associated with the expanding members78and a second diameter D12associated with the annular body82. The first diameter D10of the throughbore76is approximately equal to the diameter D5of the end section46but smaller than the diameter D6of the annular protrusion54. In addition, the first diameter D10of the throughbore76is smaller than the diameter D3of the second shoulder44and diameter D2of the first shoulder40, such that as the sleeve22is slid over the bullet20, the expanding members78are forced open by the tapered section28of the bullet20. The expanding members78may include at least one barb or engaging portion84for engaging or securing the sleeve22in the boney structure18. In this exemplary embodiment, the expanding members78include three barbs84for engagement with the boney structure18.

With continuing reference toFIGS. 3 and 4, and additional reference toFIGS. 5 and 6a method according to various embodiments for using the device10is illustrated. After the hole16has been drilled into the boney structure18, the flexible strand38can be wrapped around the soft tissue14and threaded through the eyelets36of the bullet20. The flexible strand38may be pulled tight to the bullet20causing the soft tissue14to be pierced by the guide pin12. The shape of the bullet20allows for minimal contact of the flexible strand38with the boney structure18to protect the flexible strand38during the insertion of the bullet20into the boney structure18. In particular, the configuration of the eyelets36enables at least a portion of the flexible strand38to pass through at least a portion of the bullet20. The positioning of the flexible strand38in the bullet20may assist in ensuring that the flexible strand38is not exposed to possible sources of abrasion. In addition, the placement of the flexible strand38within the bullet20ensures that the flexible strand38does not interfere with the operation of the sleeve22.

Once the soft tissue14is secured to the bullet20, the instrument58is attached to the bullet20. Specifically, the first and second cupped flanges66,68removably engage the bullet20to enable a surgeon to then insert the bullet20with the connected soft tissue14and guide pin12into the predrilled hole16in the boney structure18.

After the bullet20has been inserted into the pre-drilled hole16, the instrument58is detached from the bullet20. The sleeve22may be placed on the guide pin12and pushed down the guide pin12until the expanding members78firmly engage the boney structure18and the annular protrusions54have secured the sleeve22to the bullet20. The sleeve22is generally configured such that when the sleeve22is fully engaged with the boney structure18, the sleeve22does not extend beyond a surface86of the boney structure18. Once the rivet10is fully secured in the boney structure16, the guide pin12may be removed by applying a retractive force F. The removal of the guide pin12causes the stepped portion75of the guide pin12to engage the stepped portion29of the bullet20. The continued application of the retractive force F causes the stepped portion75of the guide pin12to shear the stepped portion29from the bullet20, resulting in the bore32becoming devoid of the stepped portion29which previously separated the cup-shaped section24from the tapered section28. The shearing of the stepped portion29of the bullet20ensures that the expanding members78are firmly engaged in the boney structure18.

The anchor or rivet10may allow for a more efficient and quick surgical reattachment of a soft tissue portion. Thus, the rivet10may decrease the time needed to complete a soft tissue reattachment or repair. The ability of the rivet10to securely engage boney structures18ensures the soft tissue16is held close to the bone for improved healing time.