US20170020589A1

US20170020589A1 - Anchor having a controlled driver orientation

Info

Publication number: US20170020589A1
Application number: US15/284,689
Authority: US
Inventors: Steven Mark Bowman; Alfred R. Berube; Bernard Joseph Bourque; Wei Yang; Mark Edwin Housman; John Stroncek
Original assignee: Smith and Nephew Inc
Current assignee: Smith and Nephew Inc
Priority date: 2010-03-10
Filing date: 2016-10-04
Publication date: 2017-01-26
Also published as: US9579188B2; US20140081339A1

Abstract

The present disclosure relates to an interference screw having a body with a proximal end, distal end, and longitudinal axis extending between thereinbetween. The screw further includes threads for fixing the screw into bone. The screw further includes a through bore defined by the body. The through bore extends between the proximal and distal ends along the longitudinal axis, and has a surface. The screw further includes a controlling member formed by the through bore surface. To install the screw into bone, a surgeon turns the screw with a driver that engages with the controlling member. The driver only engages the controlling member when it is in a driving orientation with respect to the controlling member. Advantageously, with this “one-way” engagement the surgeon can control and confirm the orientation of the driver without seeing the driver and/or screw.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent application Ser. No. 14/085,295, filed Nov. 20, 2013, which in turn is a continuation-in-part application of U.S. patent application Ser. No. 13/044,777, filed Mar. 10, 2011, now U.S. Pat. No. 8,979,865, which in turn claims priority to U.S. Patent Application Ser. No. 61/312,291, filed Mar. 10, 2010, U.S. Patent Application Ser. No. 61/334,808, filed May 14, 2010, and U.S. Patent Application Ser. No. 61/359,080, filed Jun. 28, 2010 the disclosures of which are incorporated herein by reference in their entireties for all purposes.

BACKGROUND

Field of Technology
The present disclosure relates to medical apparatuses and procedures in general, and more particularly to medical apparatuses and procedures for reconstructing a ligament.
Related Art
In many cases, ligaments are torn or ruptured as the result of an accident. Accordingly, various procedures have been developed to repair or replace such damaged ligaments.
For example, in the human knee, the anterior and posterior cruciate ligaments (i.e., the “ACL” and “PCL”) extend between the top end of the tibia and the bottom end of the femur. Often, the anterior cruciate ligament (i.e., the ACL) is ruptured or torn as the result of, for example, a sports-related injury. Consequently, various surgical procedures have been developed for reconstructing the ACL so as to restore substantially normal function to the knee.
In many instances, the ACL may be reconstructed by replacing the ruptured ACL with a graft ligament. More particularly, in such a procedure, bone tunnels are generally formed in both the top of the tibia and the bottom of the femur, with one end of the graft ligament being positioned in the femoral tunnel and the other end of the graft ligament being positioned in the tibial tunnel, and with the intermediate portion of the graft ligament spanning the distance between the bottom of the femur and the top of the tibia. The two ends of the graft ligament are anchored in their respective bone tunnels in various ways well known in the art so that the graft ligament extends between the bottom end of the femur and the top end of the tibia in substantially the same way, and with substantially the same function, as the original ACL. This graft ligament then cooperates with the surrounding anatomical structures so as to restore substantially normal function to the knee.
In some circumstances, the graft ligament may be a ligament or tendon which is harvested from elsewhere within the patient's body, e.g., a patella tendon with or without bone blocks attached, a semitendinosus tendon and/or a gracilis tendon.
As noted above, various approaches are well known in the art for anchoring the two ends of the graft ligament in the femoral and tibial bone tunnels.
In one well-known procedure, which may be applied to femoral fixation, tibial fixation, or both, the end of the graft ligament is placed in the bone tunnel, and then the graft ligament is fixed in place using a headless orthopedic screw, generally known in the art as an “interference” screw. More particularly, with this approach, the end of the graft ligament is placed in the bone tunnel and then the interference screw is advanced into the bone tunnel so that the interference screw extends parallel to the bone tunnel and simultaneously engages both the graft ligament and the side wall of the bone tunnel. In this arrangement, the interference screw essentially drives the graft ligament laterally, into engagement with the opposing side wall of the bone tunnel, whereby to secure the graft ligament to the host bone with a so-called “interference fit”. Thereafter, over time (e.g., several months), the graft ligament and the host bone grow together at their points of contact so as to provide a strong, natural joinder between the ligament and the bone.
Interference screws have proven to be an effective means for securing a graft ligament in a bone tunnel in a number of applications, such as ACL reconstruction surgery and biceps tenodesis. However, the interference screw itself generally takes up a substantial amount of space within the bone tunnel, which can limit the surface area contact established between the graft ligament and the side wall of the bone tunnel. This in turn limits the region of bone-to-ligament in-growth, and hence can affect the strength of the joinder. By way of example but not limitation, it has been estimated that the typical interference screw obstructs about 50% of the potential bone-to-ligament integration region.
For this reason, substantial efforts have been made to provide interference screws fabricated from absorbable materials, so that the interference screw can eventually disappear over time and bone-to-ligament in-growth can take place about the entire perimeter of the bone tunnel. To this end, various absorbable interference screws have been developed which are made from biocompatible, bioabsorbable polymers, e.g., polylactic acid (PLA), polyglycolic acid (PGA), etc. These polymers generally provide the substantial mechanical strength needed to advance the interference screw into position, and to thereafter hold the graft ligament in position while bone-to-ligament in-growth occurs, without remaining in position on a permanent basis.
In general, interference screws made from such biocompatible, bioabsorbable polymers have proven clinically successful. However, these absorbable interference screws still suffer from several disadvantages. First, clinical evidence suggests that the quality of the bone-to-ligament in-growth is somewhat different than natural bone-to-ligament in-growth, in the sense that the aforementioned bioabsorbable polymers tend to be replaced by a fibrous mass rather than a well-ordered tissue matrix. Second, clinical evidence suggests that absorption generally takes a substantial period of time, e.g., on the order of three years or so. Thus, during this absorption time, the bone-to-ligament in-growth is still significantly limited by the presence of the interference screw. Third, clinical evidence suggests that, for many patients, absorption is never complete, leaving a substantial foreign mass remaining within the body. This problem is exacerbated somewhat by the fact that absorbable interference screws generally tend to be fairly large in order to provide them with adequate strength, e.g., it is common for an interference screw to have a diameter (i.e., an outer diameter) of 8-12 mm and a length of 20-25 mm.
Thus, there is a need for a new and improved interference fixation system which (i) has the strength needed to hold the graft ligament in position while bone-to-ligament in-growth occurs, and (ii) promotes superior bone-to-ligament in-growth.

SUMMARY

In one aspect, the present disclosure relates to an interference screw. The screw includes a body having a proximal end, a distal end, and a longitudinal axis extending between the proximal end and distal end. The screw further includes threads extending in an open helical form between the proximal end and distal end of the body. The screw further includes a through bore defined by the body extending between the proximal end and distal end of the body along the longitudinal axis. The through bore has a surface from which a controlling member is formed. The controlling member being engaged by a driver when the driver is in a driving orientation with respect to the controlling member. The controlling member being not engaged by the driver when the driver is in an orientation different than the driving orientation.
In another aspect, the present disclosure relates to a method for installing an interference screw into bone. The method includes removing a driver from a body of an interference screw inserted into bone. The body has a proximal end, a distal end, and a longitudinal axis extending between the proximal end and distal end. The body defines a through bore extending between the proximal end and distal end along the longitudinal axis. The through bore has a surface. The method further includes engaging a controlling member formed by the surface of the through bore with the driver. The controlling member being engaged by the driver when the driver is in a driving orientation with respect to the controlling member. The controlling member not being engaged by the driver when the driver is in an orientation different than the driving orientation. The method further includes confirming the orientation of the driver in the body of the screw based on the engagement of the controlling member with the driver.
In yet another aspect, the present disclosure relates to another method for installing an interference screw into bone. The method includes inserting, initially, a driver into a through bore defined by a body of a screw inserted into bone. The through bore extends between a proximal end and a distal end of the body along a longitudinal axis extending between the proximal end and distal end of the body. The through bore has a surface. The method further includes rotating the driver within the through bore, about the longitudinal axis of the body, until the driver engages a controlling member formed by the surface of the through bore. The engagement confirms a driving orientation of the driver with respect to the controlling member. The method further includes driving the screw further into the bone with the driver in the driving orientation.
Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present disclosure and together with the written description serve to explain the principles, characteristics, and features of the disclosure. In the drawings:

FIG. 1 shows a first embodiment of the delivery device of the present disclosure.

FIG. 2 shows a side view of the shaft of the delivery device of FIG. 1.

FIG. 2A shows an exploded view of the distal end of the shaft of FIG. 2.

FIG. 3 shows a cross-sectional view of the shaft of FIG. 2.

FIG. 4 shows a front view of the distal end of the shaft of FIG. 2.

FIG. 5 shows an isometric view of the screw for use with the shaft of FIG. 2.

FIG. 6 shows a side view of the screw of FIG. 5.

FIG. 7 shows a cross-sectional view of the screw of FIG. 6.

FIG. 8 shows a second embodiment of a shaft of the present disclosure.

FIG. 9 shows a side view of the inner member of the shaft of FIG. 8.

FIG. 9A shows an exploded view of the distal end of the inner member of FIG. 9.

FIG. 10 shows a cross-sectional view of the inner member of the shaft of FIG. 9.

FIG. 11 shows a front view of the distal end of the inner member of FIG. 9.

FIG. 12 shows an isometric view of the outer member of the shaft of FIG. 8.

FIG. 13 shows a cross-sectional view of the outer member of FIG. 12.

FIGS. 14 and 15 show side views of the shaft of FIG. 8 with the outer member in different positions.

FIG. 16 shows an isometric view of a third embodiment of a shaft of the present disclosure and a screw for use with the shaft.

FIG. 17 shows an isometric view of the shaft of FIG. 16.

FIG. 18 shows an isometric view of the screw of FIG. 16.

FIG. 19 shows a side view of the screw of FIG. 16.

FIG. 20 shows a cross-sectional view of the screw of FIG. 19.

FIG. 21 shows an isometric view of a fourth embodiment of a shaft of the present disclosure and a screw for use with the shaft.

FIG. 22 shows an isometric view of the screw of FIG. 21.

FIG. 23 shows an isometric view of the shaft of FIG. 21.

FIG. 24 shows an isometric view of the shaft of FIG. 21 and an alternative screw for use with the shaft.

FIG. 25 shows a side view of the screw of FIG. 24.

FIG. 26 shows a cross-sectional view of the screw of FIG. 24.

FIG. 27 shows a side view of an interference screw the entire length of which is supported by a driver.

FIG. 28 shows a side view of an interference screw the entire length of which is not supported by a driver.

FIG. 29 shows a side view of an interference screw that has failed, structurally.

FIGS. 30A-30C show an example of an interference screw with a controlling member being inserted further into bone.

FIG. 31 shows a side view of an example of the interference screw with the controlling member.

FIG. 32 shows an end view of an example of the interference screw with the controlling member.

FIG. 33A shows a top view of a cross section of a driver in a driving orientation with respect to the interference screw.

FIG. 33B shows a top view of a cross section of a driver in an orientation different then the driving orientation of FIG. 33A.

FIGS. 34A and 34B show examples of the controlling member.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses.
FIG. 1 shows a first embodiment of the delivery device 10 of the present disclosure. The device 10 includes a handle assembly 11 and a shaft 12 coupled to the handle assembly 11. The handle assembly 11 includes a handle 11 a and a connector 11 b coupled to the handle 11 a. The connector 11 b has a channel 11 b′ and an opening 11 b″ to the channel 11 b′. The opening 11 b″ is in the shape of a “D”. A proximal end 12 a of the shaft 12 is disposed within the channel 11 b′.
FIGS. 2, 2A, and 3-4 show the shaft 12. The shaft 12 includes a proximal end 12 a and a distal end 12 b. The proximal end 12 a is in the shape of a “D” to match the shape of the opening 11 b″. The distal end 12 b includes threads 12 c, grooves 12 d, and a depth stop 12 e. The grooves 12 d extend a partial length of the shaft 12 and intersect the threads 12 c. The depth stop 12 e is for use with a depth stop on a screw that the device 10 is used to implant into a bone tunnel during ligament reconstruction surgery.
FIGS. 5-7 show the screw 20 for use with the delivery device 10 of the present disclosure. The screw 20 includes a proximal end 21 and a distal end 22. A majority of the screw 20 includes screw threads 23 in the form of an open helical coil, i.e. a connected series of continuous regularly spaced turns extending in a helical or spiral form substantially from the proximal end 21 to the distal end 22 with apertures 24 being defined by the space between the turns of the coil. In other words, interference screw 20 may include an open helical coil defining an internal volume, with the internal volume communicating with the region exterior to the open helical coil through the spacing between the turns of the open helical coil. The distal end 22 also includes a depth stop 25 that extends a partial length of the screw 20. The depth stop 25 includes a proximal end 25 a and a distal end 25 b. Additionally, a plurality of longitudinally-extending runners 26 extend along the interior of the screw threads 23.
The distal end 12 b of the shaft 12 is placed within the interior of the screw 20, via the opening 27, until the proximal end 25 a of the depth stop 25 engages the depth stop 12 e of the shaft 12. During insertion of the shaft 12 into the screw 20, the runners 26 engage the grooves 12 d and become housed within the grooves 12 d. As shown in FIG. 1, the distal end 12 b of the shaft 12 also includes hash marks 12 f, each of which is associated with a number 12 g. Once the screw 20 is placed on the shaft 12, the proximal end 21 of the screw 20 aligns with one of the hash marks/numbers 12 f, thereby indicating the length of the screw 20.
FIGS. 8, 9-9A, and 10-15 show an alternative shaft 30 of the present disclosure. The shaft 30 includes an inner member 31 and an outer member 32 disposed over the inner member 31. The proximal end 31 a of the inner member 31 is similar in shape to the proximal end 12 a of the shaft 12. The distal end 31 b of the inner member 31 includes threads 31 c. Grooves 31 d extend along the member 31 and intersect the threads 31 c. Additionally, threads 31 e are located between the proximal and distal ends 31 a,31 b of the member 31. The outer member 32 includes a first section 32 a and a second section 32 b. The first section 32 a has a larger diameter than the second section 32 b. The first section 32 a also includes threads 32 c on an inner wall 32 d of the outer member 32.
Once the outer member 32 is disposed over the inner member 31, threads 32 c engage threads 31 e to move the outer member 32 relative to the inner member 31. Moving the outer member 32 relative to the inner member 31 allows for more or less of the distal end 31 b of the inner member 31 to be shown. Similar to the distal end 12 b of the shaft 12, the distal end 31 b of inner member 31 includes hash marks/numbers (not shown) that align with an end 32 b′ of the second section 32 b, thereby indicating a length of screw 40 that will be disposed on the distal end 31 b of the inner member 31. As shown in FIGS. 14 and 15, the outer member 32 is located at different positions along the length of the inner member 31 to allow for screws 40 of different lengths to be loaded on the distal end 31 b of the inner member 31.
A handle assembly, similar to the handle assembly 11, is coupled to the proximal end 31 a of the inner member 31. Similar to screw 20, screw 40 includes a proximal end 41 and a distal end 42. The screw 40 includes screw threads 43 in the form of an open helical coil having an interior and a plurality of longitudinally-extending runners 45 extending along the interior of the screw threads 43. Screw 40 is more fully described in United States Patent Application Publication No. 20080154314, the disclosure of which is incorporated herein by reference in its entirety. Once the outer member 32 has been moved to indicate the screw length, the screw 40 is loaded onto the distal end 31 b, such that a proximal end 41 of the screw 40 engages the end 32 b′ and the runners 45 engage the grooves 31 d and become housed within the grooves 31 d.
FIGS. 16-20 show another alternative embodiment of the shaft 50 and screw 60 of the present disclosure. The shaft 50 includes a first portion 51 including a proximal end 51 a and a distal end 51 b and a second portion 52 including a first area 52 a and a second area 52 b. The proximal end 51 a is configured to be coupled to a handle assembly, similar to the handle assembly 11. However, other handle assemblies may be used. The first area 52 a has a smaller diameter than the first portion 51, such that a first depth stop 51 b′ exists at the distal end 51 b of the first portion 51. The second area 52 b has a smaller diameter than the first area 52 a such that a second depth stop 52 c exists between the first area 52 a and the second area 52 b. An end 52 b′ of the second area 52 b is tapered to allow for easier insertion of the anchor 60 into a bone during ligament reconstruction surgery, as will be further described below. The second portion 52 also includes grooves 53 extending between the first and second areas 52 a,52 b. For the purposes of this disclosure, there are three grooves 53. However, the second portion 52 may include a higher or lower number of grooves 53.
Similar to screw 20 shown in FIGS. 5-7, screw 60 includes a proximal end 61 and a distal end 62. A majority of the screw 60 includes screw threads 63 in the form of an open helical coil, i.e. a connected series of continuous regularly spaced turns extending in a helical or spiral form substantially from the proximal end 61 to the distal end 62 with apertures 64 being defined by the space between the turns of the coil. In other words, interference screw 60 may include an open helical coil defining an internal volume, with the internal volume communicating with the region exterior to the open helical coil through the spacing between the turns of the open helical coil. The distal end 62 also includes a depth stop 65 that extends a partial length of the screw 60. The depth stop 65 includes a proximal end 65 a and a distal end 65 b. Unlike the open depth stop 25 of screw 20 most clearly shown in FIG. 5, the depth stop 65 of screw 60 is a closed depth stop, most clearly shown in FIG. 18. Additionally, a plurality of longitudinally-extending runners 66 extend along the interior of the screw threads 63.
The second portion 52 of the shaft 50 is placed within the interior of the screw 60, via the opening 67, until the proximal end 65 a of the depth stop 65 engages the second depth stop 52 c of the shaft 50. During insertion of the shaft 50 into the screw 60, the runners 66 engage the grooves 53 and become housed within the grooves 53. The screws 60 may be of a variety of lengths. For example, a screw 60 may be of such length that its proximal end 61 would engage the first depth stop 51 b′.
As described above, during ligament reconstruction surgery, the end of the graft ligament is placed in the bone tunnel and then the interference screw 20,40,60 is advanced into the bone tunnel via the use of shafts 12,30,50 so that the interference screw 20,40,60 extends parallel to the bone tunnel and simultaneously engages both the graft ligament and the side wall of the bone tunnel. The screws 20,40,60 may be used in either the femoral or tibial tunnels. Methods of ligament reconstruction via use of the screws 20,40,60 is further shown in the '314 publication shown above.
FIGS. 21-23 show yet another alternative embodiment of the screw 100 and the delivery device 200 of the present disclosure. The screw 100 includes a proximal end 101 and a distal end 102. A majority of the screw 100 includes screw threads 103 in the form of an open helical coil, i.e. a connected series of continuous regularly spaced turns extending in a helical or spiral form substantially from the proximal end 101 to the distal end 102 with apertures 104 being defined by the space between the turns of the coil. In other words, interference screw 100 may include an open helical coil defining an internal volume, with the internal volume communicating with the region exterior to the open helical coil through the spacing between the turns of the open helical coil. The distal end 102 also includes a suture bridge 105 that extends a partial length of the screw 100. The suture bridge 105 includes a proximal end 105 a and a distal end 105 b. The distal end 105 b includes a concave shape. A flexible member 110, such as a suture, is housed within the screw 100, such that the suture 110 extends around the distal end 105 b of the bridge 105. Additionally, longitudinally-extending runners 106 extend from the suture bridge 105 and along the interior of the screw threads 103. For the purposes of this disclosure, there are two longitudinally extending runners 106. However, more or less than two runners are within the scope of this disclosure.
The delivery device 200 includes a distal end 201 having a slot 202 and grooves 203 extending from the slot 202 on each side of the device 200. As shown in FIG. 21, the screw 100 is located on the distal end 201 such that the suture bridge 105 is housed within the slot 202 and the runners 106 are housed within the grooves 203. The delivery device 200 is cannulated, such that when the screw 100 is located on the device 200, the suture ends 110 a, 110 b extend through the cannulation 204.
FIGS. 24-26 show a screw 300 similar to screw 100. However, screw 300 additionally includes a pointed tip 311 located on the distal end 302. The tip 311 includes a through hole 312. The hole 312 helps in locating the suture 110 within the interior of the screw 300. As shown in FIG. 24, the screw 300 is located on the distal end 201 of delivery device 200 such that the suture bridge 305 is housed within the slot 202 and the runners 306 are housed within the grooves 203. As stated above, the delivery device 200 is cannulated, such that when the screw 300 is located on the device 200, the suture ends 110 a,110 b extend through the cannulation 204, as shown in FIG. 24.
For clarity purposes, only the distal end 201 of the device 200 is shown. However, the device 200 would include a proximal end, similar to the devices above, which may be coupled to a handle assembly, similar to handle assembly 11 above. The screws 100,300 are used in the repair of soft tissue, specifically to re-attach tissue to bone. One example of this repair is when the screw 100,300 is delivered into bone via the use of device 200, the device 200 is removed from screw 100,300, the tissue is placed on the bone to be adjacent the screw 100,300, the suture ends 110 a,110 b are pulled through the tissue, and then the suture ends 110 a,110 b are tied. A hole may be made in the bone prior to insertion of the screw 100,300 into the bone. However, screw 300 may be inserted into bone without first making a hole in the bone. In this case, the pointed tip 311 is used to start insertion of the screw 300 into the bone and then rotary motion may be used to complete insertion of the screw 300 into the bone. Other methods of tissue repair via use of these screws and delivery device may also be used.
The handle 11 a of handle assembly 11 is made from plastic, however, other non-metal and metal materials may also be used. The shape and size of handle 11 a may be any shape and size necessary to help facilitate insertion of the screw 20 into bone. The coupler 11 b is made from a metal material, such as stainless steel or titanium, but may be made from other metal and non-metal materials that are strong enough to withstand the forces applied during surgery. The coupler 11 b is press-fit to the handle 11 a, but may be coupled to the handle 11 a in any other manner known to those of skill in the art. The size and shape of the coupler 11 b may be any size and shape necessary to help facilitate insertion of the screw 20 into bone. The channel 11 b′ may be any length necessary and the opening 11 b″ may be any shape necessary to facilitate coupling of the shaft 12 to the coupler 11 b.
The shaft 12 is made from a metal material, such as stainless steel and titanium, however, other metal and non-metal materials that would withstand the forces applied during surgery may be used. The diameter of the shaft 12 may vary. The proximal end 12 a of the shaft 12 may be any shape necessary to facilitate insertion of the end 12 a through opening 11 b″ and into channel 11 b′. The number of threads 12 c and grooves 12 d may vary and the lengths of the grooves 12 d may also vary. The location of depth stop 12 e may also vary based on the diameter of the shaft 12 and the diameter of the screw 20 that is used. The grooves 12 d, depth stop 12 e, and threads 12 c may be formed by any method known to one of skill in the art.
The screw 20 is made from a polymer material via a molding method. However, other material, which would allow the screw 20 to withstand forces applied during surgery, and other methods of making may be used. The depth stop 25 is open ended and doesn't extend the entire inner diameter of the screw 20. The amount of screw inner diameter that the depth stop 25 covers may vary and the length of the depth stop 25 may vary based on the diameter of the screw. The number and length of the runners 26 may also vary. Once the screw 20 is located on the shaft 12, the distal end 12 b of the shaft 12 extends from the distal end 22 of the screw 20. During insertion of the screw 20 into bone, the threads 12 c create threads in the bone, thereby creating a seat for the screw threads 23, as described more fully in the '314 publication. The amount of the distal end 12 b of the shaft 12 that extends from the distal end 22 of the screw 20 may vary.
The diameters of the first and second sections 32 a,32 b of outer member 32 may vary and the number of threads 32 c may also vary. The number of threads 31 c,31 e and grooves 31 d may vary and the lengths of the grooves 31 d may also vary. The inner and outer members 31,32 are made from a metal material, such as stainless steel and titanium, and via a method known to one of skill in the art. However, other materials may also be used. The screw 40 is made from a polymer material via a molding method. However, other material and methods of making may be used. The number and length of the runners 45 may also vary. Once the screw 40 is located on the shaft 30, the distal end 31 b of the shaft 30 extends from the distal end 42 of the screw 40. During insertion of the screw 40 into bone, the threads 31 c create threads in the bone, thereby creating a seat for the screw threads 43, as described more fully in the '314 publication. The amount of the distal end 31 b of the shaft 30 extending from the screw 40 may vary.
The shaft 50 is made from a metal material, such as stainless steel or titanium, but may be made from another metal material or a non-metal material that is strong enough to withstand the force applied to the shaft 50 during surgery. The shaft 50 may be made via a method known to one of skill in the art. The diameters of the first and second portions 51,52 may vary along with the number and lengths of the grooves 53 and the locations of the depth stops 52 c,51 b′ may vary based on the diameter of the screw 60 or other factors. Rather than being tapered, the end 52 b′ may be designed in another manner to allow easier insertion of the screw 60 into bone. The screw 60 is made from a polymer material via a molding method. However, other material, which would allow the screw to withstand the forces applied during surgery, and other methods of making may be used. The number and length of the runners 66 may also vary. Once the screw 60 is located on the shaft 50, the second portion 52 of the shaft 50 extends from the distal end 62 of the screw 60. The amount of the second portion 52 extending from the screw 60 may vary. Additionally, the length of the depth stop 65 may also vary based on the diameter of the screw 60 or other factors.
The delivery device 200 is made from a metal material, such as stainless steel or titanium, but may be made from a non-metal material that is strong enough to withstand the forces applied to the device 200 during surgery. The delivery device 200 is made via a method known to one of skill in the art. The screws 100,300 are made from a polymer material and via a molding process, however, other material, which would allow the screw to withstand the forces applied during surgery, and other processes known to one of skill in the art may be used. The suture bridge 105 may have a distal end 105 b having a shape other than concave and the length of the suture bridge 105, the slot 202, and the grooves 203 may vary. The size and the shape of the hole 312 may vary.
With some interference screw designs, it is necessary to support the entire length of an screw (or a substantial portion thereof) with a driver, as shown in FIG. 27, in order to insert the screw into bone properly. The need is especially great when the screw is made from a weak and/or brittle material, such as an osteoconductive material. This is also prevalent when the screw has fenestrations or openings that reduce the flexural (torsional) strength of the screw. Inserting the screw into bone when it is not fully supported, as shown in FIG. 28, may result in the screw failing, as shown in FIG. 29. With some screw designs, the orientation of the driver with respect to the screw determines whether the screw is fully supported or not. Accordingly, in these designs, there is a need to control the orientation of the driver with respect to the screw.
It may not be possible or it may be difficult for a surgeon to see the screw and/or driver and confirm the orientation of the driver with respect to the screw. For example, a surgeon's view may be obstructed when the screw is partly installed in bone. Accordingly, there is a further need to confirm the orientation of the driver with respect to the screw blindly.
FIGS. 30A-C show the surgeon driving an example of an screw 400 with a controlling member into bone 401. As shown, the screw 400 sits proud of the surface of the bone 401. The surgeon drives the screw 400 further into the bone 401, so that it sits flush with the bone surface, by inserting a driver 450 into the screw 400. The surgeon then rotates of the driver 450 within the screw 400 until it engages the controlling member of the screw 400. Engagement of the driver 450 with the controlling member confirms that the driver 450 is in the proper “driving” orientation and provides the surgeon with the confidence that the screw 400 is fully supported by the driver 450. The surgeon can then drive the screw 400 into the bone 401 without worry of the screw 400 failing.
FIG. 31 shows an example of the screw 400 having a body 405. The body 405 includes a proximal end 410, distal end 415, and longitudinal axis 420 extending between the proximal and distal ends 410, 415. The body 405 may be made from a bioabsorbable, non-bioabsorbable, osteoconductive or composite material. Examples of a non-bioabsorbable material include polyether ether ketone (PEEK), titanium, and surgical stainless steel. The screw 400 further includes threads 425 extending in an open helical form between the proximal end 410 and distal end 415 of the body 405. In some examples of the screw 400, the threads 425 are similar to the threads 63 described above with reference FIGS. 5-7.
FIG. 32 shows the body 405 defining a through bore 430. The through bore 430 extends between the proximal and distal ends 410, 415 of the body along the longitudinal axis 420. The through bore 430 has a surface 435. The screw 400 includes a controlling member 440 formed by the through bore surface 435. The driver 450 engages the controlling member 440 when the driver 450 is in a driving orientation with respect to the screw 400. The driver 450 does not engage the controlling member 440 when the driver 450 is in an orientation different than the driving orientation.
One example of the controlling member 440 shown in FIG. 32 includes a plurality of runners 445 extending between the proximal and distal ends 410, 415 of the body 405 along the longitudinal axis 420. Three runners (445 a, 445 b, 445 c) are shown but other multiples of runners are possible (e.g., two and four). The plurality of runners 445 is spaced equally around the circumference of the through bore 430. There is an equal distance (d) between each of the runners (445 a, 445 b, 445 c) (the distance (d) being measured, for example, from centerline to centerline of each of the runners). The runners (445 a, 445 b, 445 c) can be described as being arranged in a radial manner about the longitudinal axis 420 (coming out of the page of the figure). As such, the position of each of the runners (445 a, 445 b, 445 c) can be described as being at 0° (12 o'clock), at 120° (4 o'clock), and at 240° (8 o'clock), respectively.
One of the plurality of runners is of different shape and/or size than the other runners. A convenient example of the controlling member 440 includes one runner (445 a) having a cross sectional shape based on a rectangle and the other runners (445 b, 445 c) having a cross sectional shape based on a semi-circle. Other cross sectional shapes are possible. In another example of the controlling member 440, the dimension(s) of one or more of the runners (445 a, 445 b, 445 c), for example the width and/or height, varies with the overall size of the screw 400. For example, a first anchor is larger in size than a second anchor. In the first anchor, the height of runners is taller than the height of runners associated with the second anchor.
Turning now to FIGS. 33A-33B, which are views looking down at cross sections of the driver 450. The driver 450 used by the surgeon to turn the screw 400 into bone 401 includes grooves 455. The grooves 455 have an inverse geometry of the plurality of runners 445. When the driver 450 is in the driving orientation shown in FIG. 33A, the corresponding driver grooves 455 house the plurality of runners 445, thus, enabling the surgeon to turn the screw 400 using the driver 450. When the driver 450 is not in the driving orientation, as shown in FIG. 33B, the corresponding driver grooves 455 do not house the plurality of runners 445 (represented in the figure as hidden lines) and surgeon cannot turn the screw 400 using the driver 450. In the example shown in FIG. 33B, in order for the driver grooves 455 to house the plurality of runners 445, the driver is turned counterclockwise (in the direction of the drawn arrow), from the 10 o'clock to 9 o'clock position.
The foregoing arrangement provides a “one-way” engagement that is advantageous because the surgeon can control and confirm the orientation of the driver 450 without seeing the driver 450 and/or screw 400 i.e., the procedure can be done blindly. If the surgeon inserts the driver 450 into the screw 400 and is able to rotate it freely (i.e., without resistance) or is not able to insert the driver 450 into the screw 400 at all, then the surgeon knows that the driver 450 is not in the driving orientation. The surgeon can then rotate the driver 450 until it engages the controlling member 440 of the screw 400. Engaging the controlling member 440 causes the screw 400 to be driven into the bone and consequently, the surgeon must turn the driver 450 harder. As such, advantageously some examples of the screw 400 provide tactile feedback that enables the surgeon to seek the proper driver orientation.
FIG. 34A shows another example of the controlling member 440 that includes a plurality of runners 445′ extending between the proximal and distal ends 410, 415 of the body 405 along the longitudinal axis 420. The plurality of runners 445′ is spaced unequally around the circumference of the through bore 430. There is a different distance (d, d′, d″) between each of the runners 445′ (the distances (d, d′, d″) being measured, for example, from centerline to centerline of each of the runners). Described in the terms of radial arrangement, the positions of the runners 445′ are such that the number degrees separating positions are not equal.
FIG. 34B shows yet another example of the controlling member 445 that includes a plurality of runners 445″ extending between the proximal and distal ends 410, 415 of the body 405 along the longitudinal axis 420. The plurality of runners 445″ is spaced equally around the circumference of the through bore 430. The example controlling member 440 further includes a tab 460 spaced between an adjacent pair of runners (445 a″ and 445 b″). Another example of the controlling member 440 includes a plurality of runners spaced unequally around the circumference of the through bore with a tab spaced between an adjacent pair of runners. In some examples, the tab 460 extends part of the length of the screw 400 and is different than a runner. While the one way or “keyed” feature of the screw 400 is described with reference to the example arrangements above, those skilled in the art will readily recognize that other arrangements are possible.
Other examples of the screw 400 include a depth stop, such as the open depth stop 25 described above with reference FIG. 5 and the closed depth stop 65 described above with reference FIG. 18. The depths stop engages a depth stop of the driver 450 such that a distal end of the driver extends beyond the distal end of the body. In still other examples of the screw 400, the proximal end 410 of the body 405 aligns with a hash mark on a distal end of the driver and a number associated with the hash mark identifies the length of the body 405 of the screw 400.
In an example procedure to install the screw 400 into bone 401, the surgeon may remove the driver 450 from the body 405 of the screw 400 that has been partly inserted into bone 401. The surgeon reinserts the driver 450 into the body 405 of the screw 400 and engages the controlling member 440. The surgeon confirms the orientation of the driver 450 based on the engagement of the controlling member 440 with the driver 450. Engaging the controlling member 440 tells the surgeon that the driver 450 is in the driving orientation. The lack of engagement tells the surgeon that the driver 450 is in an orientation different than the driving orientation. In the event the driver 450 does not engage the controlling member 440 (e.g., the surgeon turns driver 450 but the screw 400 does not turn), the surgeon rotates the driver 450 within the through bore 430 until the driver 450 engages the controlling member 440 (e.g., the surgeon turns driver and the screw turns).
In the example procedure, each time the surgeon removes and reinserts the driver 450 into the screw, the surgeon controls and confirms the orientation of the driver 450 using the controlling member 440. This is advantageous because the surgeon may have to remove and reinsert the driver 450 several times during the procedure in order to install the screw 400 into bone 401, completely.
Some examples of the screw 400 may be a part of an screwing system that includes the above-described driver 450. In an example system, the screw 400 maybe “preloaded” and disposed on at a distal end of the driver 450.
As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the disclosure, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.

Claims

What is claimed is:

1. An interference screw comprising:

a body having a proximal end, a distal end, and a longitudinal axis extending between the proximal end and distal end;

threads extending in an open helical form between the proximal end and distal end of the body;

a through bore defined by the body extending between the proximal end and distal end of the body along the longitudinal axis, the through bore having a surface; and

a controlling member formed by the surface of the through bore, the controlling member configured to be engaged by a driver when the driver is in a driving orientation with respect to the controlling member and configured to not be engaged by the driver when the driver is in an orientation different than the driving orientation.

2. The interference screw of claim 1 wherein the controlling member includes a plurality of runners extending between the proximal end and distal end of the body along the longitudinal axis, the plurality of runners spaced equally around the circumference of the through bore, and one of the plurality of runners is of different shape and/or size than other runners.

3. The interference screw of claim 2 wherein the one runner has a cross sectional shape based on a rectangle and the other runners have a cross sectional shape based on a semi-circle.

4. The interference screw of claim 1 wherein the controlling member includes a plurality of runners extending between the proximal end and distal end of the body along the longitudinal axis, the plurality of runners spaced unequally around the circumference of the through bore.

5. The interference screw of claim 4 wherein one of the plurality of runners has a cross sectional shape based on a rectangle and other runners have a cross sectional shape based on a semi-circle.

6. The interference screw of claim 1 wherein the controlling member includes:

a plurality of runners extending between the proximal end and distal end of the body along the longitudinal axis, the plurality of runners spaced equally around the circumference of the through bore; and

a tab spaced between an adjacent pair of runners.

7. The interference screw of claim 1 wherein the controlling member includes:

a plurality of runners extending between the proximal end and distal end of the body along the longitudinal axis, the plurality of runners spaced unequally around the circumference of the through bore; and

a tab spaced between an adjacent pair of runners.

8. The interference screw of claim 1 wherein the body is made from a bioabsorbable, non-bioabsorbable, osteoconductive or composite material.

9. The interference screw of claim 8 wherein the non-bioabsorbable material includes polyether ether ketone (PEEK), titanium, and surgical stainless steel.

10. The interference screw of claim 1 further comprising an ingrowth core received within the through bore.

11. The interference screw of claim 10 wherein the ingrowth core is doped with bone growth factors so as to enhance bone ingrowth.

12. The interference screw of claim 1 further comprising a depth stop extending, longitudinally, a partial length of the body, the depth stop engages a depth stop of the driver such that a distal end of the driver extends beyond the distal end of the body.

13. The interference screw of claim 12 wherein the depth stop is an open depth stop encircling part of the distal end of the body.

14. The interference screw of claim 12 wherein the depth stop is a closed depth stop encircling the distal end of the body.

15. The interference screw of claim 1 wherein the proximal end of the body aligns with a hash mark on a distal end of the driver and a number associated with the hash mark identifies the length of the body of the interference screw.