Patent Publication Number: US-2020289272-A1

Title: Implants with groove patterns and soft tissue attachment features

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a division of U.S. patent application Ser. No. 15/586,642, entitled “IMPLANTS WITH GROOVE PATTERNS AND SOFT TISSUE ATTACHMENT FEATURES”, filed May 4, 2017, which is incorporated herein by reference. U.S. patent application Ser. No. 15/586,642 is a continuation of PCT application No. PCT/US2015/059528, entitled “IMPLANTS WITH GROOVE PATTERNS AND SOFT TISSUE ATTACHMENT FEATURES”, filed Nov. 6, 2015, which is incorporated herein by reference. PCT application No. PCT/US2015/059528 is based upon U.S. provisional patent application Ser. No. 62/076,901, entitled “IMPLANTS WITH GROOVE PATTERNS AND SOFT TISSUE ATTACHMENT FEATURES”, filed Nov. 7, 2014, which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to orthopaedic implants. 
     2. Description of the Related Art 
     It is well-known to implant orthopaedic implants into a patient&#39;s body to attempt to restore musculoskeletal function that the patient has lost or damaged due to injury or disease. Many orthopaedic implants, for example, are meant to replace bone tissue that has failed to heal correctly or cannot be naturally repaired by the patient&#39;s body. Such known orthopaedic implants can include femoral knee implants, hip implants, glenoid implants, etc. 
     When implanting an orthopaedic implant, it is important that the orthopaedic implant is firmly anchored (fixated) in the body. Without being firmly fixated, there is a significant risk that the implant will loosen due to movement of the surrounding anatomy, leading to implant failure and potentially more damage to the surrounding anatomy of the patient. To fixate implants in the body, traditionally an adhesive compound, known as bone cement, was used in order to provide temporary fixation before the material of the implant was integrated in the body to permanently fixate the implant. 
     One known issue with bone cement is that the cement substance is difficult to work with during surgery. Bone cement has a consistency very similar to normal cement and putties, which makes the bone cement difficult to remove from areas where it is not desired. If the incorrectly placed bone cement is not adequately removed, the bone cement can damage the anatomy adjacent to the implant during normal movement. To lessen the risk of this occurring, a surgeon might opt to use less bone cement to temporarily fixate the implant, but lessening the amount of bone cement used presents the risk of not using enough bone cement and not properly fixating the implant. 
     An alternative to using bone cement is using a fixation device, such as a bone pin or screw, that connect the implant to surrounding bone tissue. Such fixation devices can be effective, but can require significantly more operation time and planning to correctly install. Further, such fixation devices must be fixated in adjacent bone tissue by forcing the fixation devices into the adjacent bone tissue, which can cause damage to the adjacent bone tissue that will need to be surgically repaired. 
     One approach that has been tried to remove the need for bone cement is to put a porous ingrowth material on the implant that encourages bone ingrowth into and bonding with the pores of the material. The filling of the pores with bone material that bonds with the implant is an attractive solution, but the time necessary for sufficient bone ingrowth into the pores is a significant period during which the patient is unable to move the area where the implant is fixated. In the event that the patient moves or the implant otherwise manages to move during the bone ingrowth phase, there is also a possibility that the bone material in the pores will shear from the surrounding bone tissue and the pores will be filled with bone material that provides no fixation. In light of such risks, most implants that have fixating ingrowth material will still utilize bone cement or another fixation method, such as bone screws, to sufficiently fixate the implant following implantation. 
     What is needed in the art is a way to fixate orthopaedic implants in a patient&#39;s body that overcomes some of the previously described disadvantages. 
     SUMMARY OF THE INVENTION 
     The present invention provides an implant with a porous ingrowth material having grooves formed in the ingrowth material. 
     The invention in one form is directed to an orthopaedic implant including: an implant body comprising a biocompatible material and configured to be implanted at an anatomical location, the implant body defining an attachment region on an outer surface of the implant body; and an adjustable holder attached to the implant body and having a compression surface facing the attachment region, the adjustable holder being configured to be implanted at the anatomical location with the implant body and adjustably compress at least one of a soft tissue or a graft material between the compression surface and the attachment region. 
     The invention in another form is directed to a method of affixing at least one of a soft tissue or a graft material to an orthopaedic implant. The method includes implanting the orthopaedic implant at an anatomical location. The orthopaedic implant includes: an implant body including a biocompatible material and defining an attachment region on an outer surface of the implant body; and an adjustable holder attached to the implant body and having a compression surface facing the attachment region. The soft tissue and/or the graft material is compressed between the compression surface of the adjustable holder and the attachment region of the implant body. 
     An advantage of the present invention is the grooves formed in the porous ingrowth material can provide additional friction to keep the implant fixated while bone material grows into the pores to permanently fixate the implant. 
     Another advantage is the grooves can be adjusted in many different ways to suit the specific requirements of the implant. 
     Yet another advantage is the grooves can also aid tissue attachment to the implant. 
     Yet another advantage is the grooves can make the implant easy to install but difficult to remove. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a side view of an embodiment of a single groove formed in a porous material according to the present invention; 
         FIG. 2  is a perspective view of an embodiment of an acetabular cup according to the present invention with crossing helical grooves formed in a porous material; 
         FIG. 3  is a perspective view of the acetabular cup shown in  FIG. 2  with a different groove pattern; 
         FIG. 4  is a perspective view of the acetabular cup shown in  FIG. 2  with yet a different groove pattern; 
         FIG. 5  is a perspective view of an embodiment of an acetabular cup according to the present invention with non-crossing helical grooves formed in a porous material; 
         FIG. 6  is a perspective view of the acetabular cup shown in  FIG. 5  with a different groove pattern; 
         FIG. 7  is a perspective view of the acetabular cup shown in  FIG. 5  with yet a different groove pattern; 
         FIG. 8  is a perspective view of an embodiment of an acetabular cup according to the present invention with longitudinal grooves formed in a porous material; 
         FIG. 9  is a perspective view of the acetabular cup shown in  FIG. 8  with a different groove pattern; 
         FIG. 10  is a perspective view of the acetabular cup shown in  FIG. 8  with yet a different groove pattern; 
         FIG. 11  a perspective view of an embodiment of an embodiment of an acetabular cup according to the present invention with latitudinal grooves formed in a porous material; 
         FIG. 12  is a perspective view of the acetabular cup shown in  FIG. 11  with a different groove pattern; 
         FIG. 13  a perspective view of the acetabular cup shown in  FIG. 11  with yet a different groove pattern; 
         FIG. 14  a perspective view of the acetabular cup shown in  FIG. 11  with yet a different groove pattern; 
         FIG. 15  is a side view of an embodiment of an orthopaedic implant according to the present invention that includes hooks formed in a porous material for holding soft tissue; 
         FIG. 16  is a side view of an embodiment of hooks that can be formed in the orthopaedic implant shown in  FIG. 15 ; 
         FIG. 17  is a side view of another embodiment of hooks that can be formed in the orthopaedic implant shown in  FIG. 15 ; 
         FIG. 18  is a side view of yet another embodiment of hooks that can be formed in the orthopaedic implant shown in  FIG. 15 ; 
         FIG. 19  is a side view of an embodiment of a femoral knee implant according to the present invention that has a porous material with grooves formed therein; 
         FIG. 20  is a perspective view of an embodiment of a femoral hip stem according to the present invention with a porous material having grooves formed therein; 
         FIG. 21  is a perspective view of the femoral hip stem shown in  FIG. 20  with a different groove pattern formed in the porous material; 
         FIG. 22  is a perspective view of the femoral hip stem shown in  FIG. 20  with yet another different groove pattern formed in the porous material; 
         FIG. 23  is a front view of the femoral hip stem shown in  FIG. 20  with yet a different groove pattern formed in the porous material; 
         FIG. 24  is a side view of the femoral hip stem shown in  FIG. 23 ; 
         FIG. 25  is a perspective view of an embodiment of a femoral knee implant according to the present invention with a porous material having grooves formed therein; 
         FIG. 26  is a perspective view of the femoral knee implant shown in  FIG. 25  with a different groove pattern formed in the porous material; 
         FIG. 27  is a side view of the femoral knee implant shown in  FIG. 26 ; 
         FIG. 28  is a perspective view of the femoral knee implant shown in  FIG. 25  with yet another different groove pattern formed in the porous material; 
         FIG. 29  is a perspective view of the femoral knee implant shown in  FIG. 25  with yet another different groove pattern formed in the porous material; 
         FIG. 30  is a close-up perspective view of the femoral knee implant shown in  FIG. 29 ; 
         FIG. 31  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having an adjustable holder; 
         FIG. 32  is a perspective view of the orthopaedic implant shown in  FIG. 31  with the adjustable holder tightened; 
         FIG. 33  is a top view of the orthopaedic implant shown in  FIG. 31 ; 
         FIG. 34  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having an adjustable holder with a roller; 
         FIG. 35  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having an adjustable holder with a ratcheting mechanism; 
         FIG. 36  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having an adjustable holder with a compliant material placed on the holder; 
         FIG. 37  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having a holding collar and an ingrowth pad; 
         FIG. 38A  illustrates a bifurcated graft; 
         FIG. 38B  is a perspective view of the bifurcated graft shown in  FIG. 38A  being used as a collar wrapped around a hip stem; 
         FIG. 39  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention with sutures holding a graft to an ingrowth pad of the orthopaedic implant; 
         FIG. 40A  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention with a short greater trochanter that cannot reach a tendon; 
         FIG. 40B  is a perspective view of the orthopaedic implant shown in  FIG. 40A  with an elongated greater trochanter that can reach the tendon shown in  FIG. 40A ; 
         FIG. 41  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention with an adjustable holder holding a graft between two ingrowth pads; 
         FIG. 42  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention having a recessed ingrowth material; 
         FIG. 43  is a perspective view of yet another embodiment of an orthopaedic implant according to the present invention with an adjustable holder holding a graft between two ingrowth pads; and 
         FIG. 44  is a lateral view of the orthopaedic implant shown in  FIG. 43  with the holder removed and a bifurcated graft placed around an ingrowth pad. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention provides implants with grooved features that prevent implant movement, aid tissue attachment, make the implant easier to insert but more difficult to remove, or some combination of the aforementioned features. The present invention also relates to manufacturing methods for such implants. 
     Referring now to  FIG. 1 , an example groove  100  is shown that may be included on one or more surfaces  102  of an orthopedic implant. The groove  100  can be one of many grooves located on a porous section of the implant, a solid implant substrate, or a combination of the two. The grooves can have one or more of the following purposes: preventing motion, migration, back-out, tilting, translation, and rotation of the implant; aiding tissue attachment to the implant; and easing implant insertion at an implantation site while increasing the difficulty of implant removal. It should be appreciated that the previously described purposes are exemplary only and grooves can be added to medical implants according to the present invention for any desired purpose. 
     Grooves added to a medical implant can be varied between different medical implants or different regions of the same medical implant. Some of the ways in which the grooves can be varied include: the location of the grooves, the grooves&#39; pattern(s), the orientation of the grooves, the distance between grooves, and individual groove geometry. As can be seen in  FIG. 1 , each groove  100  can be formed with a first groove wall  104  and a second groove wall  106  with the groove  100  defining a depth D from the surface  102  to a bottom  108  of the groove  100 , a width W between the first groove wall  104  and second groove wall  106 , a groove angle α defined between the first groove wall  104  and second groove wall  106 , the bottom  108  defining a tip radius RT so the groove  100  has a curvature at the bottom  108 , and the groove  100  can further define a rake angle αR relative to a normal line L of the surface  102 , which is shown as a negative rake angle in  FIG. 1 . It should be appreciated that the depth D, width W, groove angle α, tip radius RT, and rake angle αR can all be varied, as desired, to form differently shaped grooves in the surface  102 . While the groove  100  shown in  FIG. 1  is shown as being formed in the surface  102  by removing material from the surface  102 , grooves can also be formed on the surface  102  by the addition of material to the surface  102 , such that the surface  102  defines a bottom of the groove. 
     The groove  100  shown in  FIG. 1  has a negative rake angle αR relative to the normal line L of the surface  102 . Negative rake angles can help with motion prevention and be used to make hooks to aid soft tissue attachment. Likewise, combining negative rake angles with the proper groove location, pattern, and orientation can make the implant easier to implant but more difficult to remove, which is described further herein. 
     The grooves can be added to the solid regions of an implant, the porous regions of an implant, or both. The groove geometry, location, orientation, and pattern allow the implant to resist motion. In cases where grooves are added to the porous region of the implant, bone and tissue ingrowth into the grooves over time also can improve the motion resistance characteristics of the implant. 
     Grooves can be added to many different types of medical or orthopedic implants. Examples include, but are not limited to acetabular shells, femoral hip stems, femoral knee implants, tibial knee implants, patellar implants, shoulder implants, spine implants, small joint implants, hand implants, ankle implants, foot implants, large reconstruction implants, and dental implants. 
     The grooves can be manufactured onto implants using the following described methods or any other known methods. Example methods that can be used to manufacture the groove onto a medical implant can include forging, casting, photochemical etching, standard (also called RAM or plunge) electrical discharge machining (EDM), wire EDM, machining, laser etching, rolling, and grinding. 
     Referring now to  FIGS. 2-4 , embodiments of an orthopaedic implant  200  according to the present invention are shown with differing groove patterns formed in a porous ingrowth material  202  posited on a semi-spherical shell  204 , which can also be referred to as an implant body. Since the orthopaedic implant  200  is intended to be implanted in a patient, the implant body  204  should be formed of a biocompatible material that is suitable for implantation into the patient. Examples of such materials can be, but are not limited to, metals such as titanium, nitinol, stainless steel, cobalt-chrome, and tantalum, as well as various polymers such as polyaryl etherketones (PAEK), polyethylene, polylactic acid (PLA), etc. The porous ingrowth material  202 , similarly, should be biocompatible and also allow for tissue infiltration into pores formed in the porous ingrowth material  202 . The porous ingrowth material  202  can be, for example, a metal with pores formed into the metal, a polymer with pores formed into the polymer, a metal foam, a polymer foam, a ceramic foam, etc. It should be appreciated that the given examples are exemplary only and any biocompatible material that is porous can serve as the porous ingrowth material  202 . To further assist tissue infiltration and integration into the porous ingrowth material  202 , some or all of the pores formed in the porous ingrowth material  202  can contain various bioactive substances that serve various roles. The bioactive substances can be, for example, tissue growth factors, antibiotics, anti-inflammatories, and painkillers. The porous ingrowth material  202  can be posited on a surface of the implant body  204  so that the porous ingrowth material  202  is a discrete element of the orthopaedic implant  200  or the porous ingrowth material  202  can also be formed as a part of the implant body  204  so the exposed surface(s) of the porous ingrowth material  202  forms a part of the exposed surface(s) of the implant body  204 . It can therefore be seen that the porous ingrowth material  202  can be provided as part of the orthopaedic implant  200  in many different configurations to provide a region of the orthopaedic implant  200  that encourages tissue ingrowth and fixation of the implant  200  in the patient. 
     As can be seen, helical grooves  206  with a first direction can be formed in the porous ingrowth material  202  that are crossed by helical grooves  208  with a second direction opposite to the first direction. This forms a pattern of crossing helical grooves  206 ,  208  in the porous ingrowth material  202 . The purposes of these grooves  206 ,  208  are to prevent rotation and tilting of the shell  204  that can occur after the orthopaedic implant  200  is placed in a patient&#39;s anatomy. Groove coverage may be 0-100% of a shell height SH of the shell  204 , which can be varied as shown in  FIGS. 2-4 , and the groove(s)  206 ,  208  may originate from an apex  210  of the shell  204 , a bottom  212  of the shell  204 , or any point in between. It should be appreciated that when referring to percentages of the “shell height” SH of the shell  204  that are covered by a groove, reference is being made to a single groove extending along a certain percentage of one height. For example, a single groove that extends from the apex  210  of the shell  204  to the bottom  212  of the shell  204  along the outer surface of the shell  204  would be considered as covering 100% of the shell height SH, as shown in  FIG. 2 , of the shell  204 , whereas a groove that only extended halfway between the apex  210  of the shell  204  to the bottom  212  of the shell  204  along the outer surface of the shell  204  would be considered as covering 50% of the shell height SH. The location, pattern, orientation, and distance between the grooves  206 ,  208  can vary, as can be seen in  FIGS. 2-4 . In addition to the shell height SH of the grooves  206 ,  208  being adjusted, a spacing distance SD between similarly directed grooves  206 ,  208  can be altered to adjust the number of grooves  206 ,  208  formed in the porous ingrowth material  202 . Likewise, the groove geometry of each formed groove, which can include the width W, depth D, groove angle α, rake angle αR, and tip radius RT as shown in  FIG. 1 , can be similar for all grooves or vary between the grooves, as desired. As shown in  FIGS. 2-4 , the grooves  206 ,  208  can have a cross pattern with helical angles ranging from 15° to 60°. Similarly directed grooves  206  and  208  can be located 5° to 45° from each other on the hemisphere. Further, the individual grooves can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, and a groove angle α of 0° to 120°. Further, the rake angle αR for the grooves  206 ,  208  can be in a range from −60° to +60°. 
     The grooves  206 ,  208  can cover the entire shell height SH of the shell  204 , or a portion of the shell  204  as shown. Helical groove coverage on the shell  204  can range from 0% to 100% of the shell height SH as well as 5 to 75% of a total surface area of the porous ingrowth material  202 . The grooves  206 ,  208  may start at the apex  210  of the shell  204 , bottom  212  of the shell  204 , or any point in between, as shown. 
     Referring now to  FIGS. 5-7 , another embodiment of an orthopaedic implant  300  is shown that includes a porous ingrowth material  302  on a semi-spherical shell  304  that has grooves  306  formed therein. The orthopaedic implant  300  is similar to the orthopaedic implants  200  shown in  FIGS. 2-4 , with all similar elements being numbered similarly with values raised by 100. As can be seen, the grooves  306  are helical, similar to the grooves  206 ,  208  shown in  FIGS. 2-4 , but all the grooves  306  are similarly directed so that none of the grooves  306  cross another groove. Such a configuration of grooves  306  can help prevent rotation and tilting of the shell  304  following implantation. Groove coverage may be 0-100% of a shell height SH of the shell  304 , and the grooves  306  may originate from the apex  310  of the shell  304 , the bottom  312  of the shell  304 , or any point in between. The location, pattern, orientation, and distance between the grooves  306  can vary. The grooves  306  can have a clockwise or counter-clockwise curvature. Likewise, each individual groove  306  can have varying groove geometry, as previously described, with dimensions that can be varied similar to the previously described grooves  206  and  208 . The grooves  306  can cover the entire shell height SH of the shell  304 , as shown in  FIG. 5 , or a portion of the shell  304 , as shown in  FIGS. 6-7 . Helical groove coverage on the shell  304  can range from 0% to 100% of the shell height SH and between 5 and 75% of the total surface area of the porous ingrowth material  302 . 
     Referring now to  FIGS. 8-10 , another embodiment of an orthopaedic implant  400  according to the present invention is shown that includes a porous ingrowth material  402  on a semi-spherical shell  404  with longitudinal grooves  406  formed therein. The orthopaedic implant  400  is similar to the orthopaedic implants  200  shown in  FIGS. 2-4 , with all similar elements being numbered similarly with values raised by 200. The longitudinal grooves  406  can prevent rotation of the shell  404  following implantation. As used herein, “longitudinal” refers to the grooves  406  being formed in the porous ingrowth material  402  such that the grooves  406  form normal angles relative to the bottom  412  of the shell  404  and are not angled with respect to the bottom  412  like the previously described helical grooves  206 ,  208 ,  306 . The grooves  406  can cover 0-100% of the shell height SH, and the grooves  406  may originate from the apex  410  of the shell  404 , the bottom  412  of the shell  404 , or any point in between. The location, pattern, orientation, and distance between the grooves  406  can vary. Likewise, the groove geometry of each groove  406  can be similar or vary, as previously described. One embodiment consists of longitudinal grooves that are located 5° to 45° from each other on the hemisphere. Further, the individual grooves  306  can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, and a groove angle α of 0° to 120°. Further, the rake angle αR can range from −60° to +60°. The grooves  406  can cover anywhere from 5 to 75% of the total surface area of the porous ingrowth material  402 . The spacing between adjacent grooves  406  can be altered to give varying number of grooves  406  in the porous ingrowth material  402 . 
     Referring now to  FIGS. 11-14 , an embodiment of an orthopaedic implant  500  according to the present invention is shown that includes a porous ingrowth material  502  on a semi-spherical shell  504  with latitudinal grooves  506  formed in the porous ingrowth material  502 . The orthopaedic implant  500  is similar to the orthopaedic implants  200  shown in  FIGS. 2-4 , with all similar elements being numbered similarly with values raised by 300. The latitudinal grooves  506  can help prevent tilting of the shell  504  following implantation in a patient. The latitudinal grooves  506  can be formed in the porous ingrowth material  502  such that the grooves  506  extend along multiple circumferences of the outer surface of the shell  504 . In this sense, the grooves  506  can have differing lengths based on where the groove is formed on the outer surface. Alternatively, one or more of the grooves  506  can be formed to not extend across the entirety of a circumference, so that the groove(s) has distinct longitudinal ends rather than being a continuous groove formed in the circumference. The location, pattern, orientation, and distance between the grooves can vary, as shown in  FIGS. 11-14 . Likewise, the groove geometry of each individual groove  506  can be varied, as previously described. The latitudinal groove  506  can be located 0.010″ to 0.500″ from each other. Further, each groove can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, and a groove angle α of 0° to 120°. Further, the rake angle αR for one or more of the grooves  506  can range from −60° to +60°. 
     The grooves  506  can cover the entire shell height SH of the shell  504  or a portion of the shell  504  as shown. Groove coverage on a shell  504  can range from 0% to 100% of the shell height SH and the grooves  506  can encompass a total surface area of the porous ingrowth material  502  ranging between 5 and 75%. 
     Referring now to  FIGS. 15-18 , another embodiment of an orthopaedic implant  600  according to the present invention is shown that has an implant body  602  with a plurality of hooks  604  for attaching a graft  606  to the implant body  602  and a cover  608  attached to the implant body  602  that can protect the graft  606  from being impacted by surrounding anatomical features. The hooks  604  can be formed to have a negative rake angle to aid soft tissue or soft tissue graft attachment, as shown. The hooks  604  can be formed, for example, by forming grooves  610  into the implant body  602  such that the hooks  604  are formed between adjacent grooves  610 . The hooks  604  can aid soft tissue attachment to the implant body  602  without killing the soft tissue due to excessive pressure and restriction of blood flow, with the cover  608  acting to protect the soft tissue or graft  606  from being forced against the hooks  604 . The location, pattern, orientation, and distance between the grooves  606  can vary. Further, the groove geometry for the hooks  604  can be varied, as previously described and can be seen in comparing the hooks  604  shown in  FIGS. 15-18 . The cover  608  can also help keep the soft tissue in place until it grows into the grooves  610 . The hooks  604  can, for example, be angled relative to a surface  612  of the implant body  602  with relatively small, round tips  614 , as shown in  FIG. 16 ; perpendicular relative to the surface  612  with relatively small, square tips  616 , as shown in  FIG. 17 ; or angled relative to the surface  612  with relatively large, round tips  618 , as shown in  FIG. 18 . Since the grooves  610  are shaped to keep the soft tissue in place, the cover  608  can be applied with little to no compressive force on the soft tissue, preventing compressive force from constricting and killing the soft tissue. One example embodiment of the invention utilizing such a configuration can be a large oncology reconstructive femoral stem where a tendon of the patient is attached directly to the femoral stem. 
     Referring now to  FIG. 19 , another embodiment of an orthopaedic implant  700  according to the present invention is shown that includes an implant body  702  formed as a femoral knee implant with a mounting portion  704  connected to at least one femoral head portion  706  with an outer articulating surface  708 . The mounting portion  704  can rest on a femur while the femoral head portion  706  can be placed at an end of the femur so that the articulating surface  708  of the femoral head portion  706  can articulate with a tibia. To help with keeping the implant body  706  fixated to the femur, a porous ingrowth material  710  can be placed on an interior surface  712  of the mounting portion  704  and formed with grooves  714  to form a series of serrated hooks  716  in the porous ingrowth material  710 . Further, an additional porous ingrowth material  718  can be attached to an interior surface  720  of the femoral head portion  706  that also has grooves  722  formed therein to form a series of serrated hooks  724  in the porous ingrowth material  718 . The grooves  714  and  722  forming the hooks  716 ,  724  can inhibit implant  700  motion after implantation due to the shape of the hooks  716 ,  724  being such that the hooks  716 ,  724  all point in a similar vertical direction  726  to allow the tips of the hooks  716 ,  724  to easily slide along a bone surface as the knee implant  702  is placed on the femur while digging into the bone surface if the knee implant  702  is moved away from the femur. The location, pattern, orientation, and distance between the grooves  714 ,  722  can vary to form a desired pattern of hooks  716 ,  724 . Further, the groove geometry of each groove  714 ,  722  can be varied as previously described. The grooves  714 ,  722  can be located 0.010″ to 0.500″ from adjacent grooves  714 ,  722  in the same porous ingrowth material  710 ,  718 . Further, the grooves  714 ,  722  can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, a groove angle α of 0° to 120°. Further, the rake angle αR of the grooves  714 ,  722  can range from −60° to +60°. 
     Referring now to  FIGS. 20-24 , another embodiment of an orthopaedic implant  800  is shown that includes a porous ingrowth material  802  placed on an implant body  804 , shown as a femoral hip stem, that has grooves  806  formed in the porous ingrowth material  802 . The hip stem  804  defines a stem axis SA and includes a femoral portion  808  that will be implanted into a femur and an acetabular portion  810  connected to the femoral portion  808  that will be implanted in an acetabulum. The femoral portion  808  has an anterior face  808 A, a posterior face  808 B (shown in  FIG. 24 ), and a pair of side faces  808 C connected to the anterior face  808 A and posterior face  808 B. As shown, the porous ingrowth material  802  is placed on each face  808 A,  808 B, and  808 C of the femoral portion  808  near the connection between the femoral portion  808  and the acetabular portion  810 . The grooves  806  can be formed in the porous ingrowth material  802  on the anterior face  808 A and/or the posterior face  808 B and can help prevent movement of the hip stem  804  in the medial to lateral direction and ease implant insertion. The grooves  806  can be oriented generally along the stem axis SA (as shown in  FIGS. 20-21 ), perpendicular to the stem axis SA, or angled relative to the stem axis SA (as shown in  FIG. 22 ). The grooves  806  may be formed as continuous straight lines in the porous material  802  or curved. The grooves  806  may cover between 0 and 100% of a proximal porous material height PH, and the grooves  806  may originate from a proximal end  812  of the porous material  802 , a distal end  814  of the porous material  802 , or any point in between. The location, pattern, orientation, and distance between the grooves  806  can vary. Likewise, the groove geometry, can vary as previously described. One example embodiment consists of curved grooves located 0.010″ to 0.500″ from each other that travel from the proximal end  812  to the distal end  814  of the proximal porous material  802 . The individual grooves can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, a groove angle α of 0° to 120°. Further, the rake angle αR can range from −60° to +60°. 
     Referring now to  FIGS. 23-24 , the orthopaedic implant shown in  FIGS. 20-22  is shown with grooves  816  having a different orientation. The grooves  816  shown in  FIGS. 23-24  are formed in the porous ingrowth material  802  on the anterior face  808 A and oriented in a medial-lateral plane of the hip stem  804  to help prevent movement of the stem  804  in the proximal to distal direction. Other than the direction in which the grooves  816  extend, the grooves  816  shown in  FIGS. 23-24  can be otherwise similar to the grooves  806  shown in  FIGS. 20-22 . 
     Referring now to  FIGS. 25-26 , yet another embodiment of an orthopaedic implant  900  according to the present invention is shown which includes a porous ingrowth material  902  placed on a femoral knee implant  904  similar to previously described femoral knee implant  702 . As can be seen, the porous ingrowth material  902  has grooves  906  formed therein and is placed on an interior surface  908  of a mounting portion  910  of the femoral knee implant  904 . The formed grooves  906  span the medial to lateral regions of the implant  904 , i.e., the grooves  906  extend in a medial-lateral direction. The medial-lateral grooves  906  can ease implantation of the implant  904  and prevent movement of the implant  904  after implantation. The grooves  906  may cover 0-100% of an implant width WI, and the grooves  906  may originate from a medial side  912  of the implant  904 , a lateral side  914  of the implant  904 , or any point in between. The location, pattern, orientation, and distance between the grooves  906  can vary, as can be seen by comparing  FIG. 25  to  FIG. 26 . Likewise, the groove geometry can vary as previously described. The grooves  906  can be located 0.010″ to 0.500″ from each other. Further, the grooves  906  can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, and a groove angle α of 0° to 120°. Further, the rake angle αR can range from −60° to +60°. 
     Referring now to  FIG. 27 , a side view of the implant  900  shown in  FIG. 26  is shown. As can be seen, the grooves  906  are formed in the porous ingrowth material  902  such that hooks  916  are formed in the porous ingrowth material  902  that can make insertion of the implant  900  easier while also making removal of the implant  900  after implantation more difficult. 
     Referring now to  FIGS. 28-30 , yet another embodiment of an orthopaedic implant  1000  according to the present invention is shown having porous ingrowth material regions  1002  placed on a femoral knee implant  1004 . The porous ingrowth material regions  1002  have grooves  1006  formed therein and can be placed on an interior surface  1008  of a mounting portion  1010  of the femoral knee implant  1004 . The grooves  1006  span the anterior to posterior regions of the implant  1004 , i.e., the grooves  1006  extend in an anterior-posterior direction. The anterior-posterior grooves  1006  can ease implantation of the implant  1004  and prevent movement of the implant  1004  in the medial-lateral directions after implantation. The grooves  1006  can cover 0-100% of an anterior to posterior distance DAP on the implant  1004 , and the grooves  1006  can originate from an anterior side  1012  of the implant  1004 , a posterior side  1014  of the implant  1004 , or any point in between. The location, pattern, orientation, and distance between the grooves  1006  can vary, as can be seen by comparing  FIG. 28  to  FIG. 29 . Likewise, the groove geometry can vary, as previously described. The grooves  1006  can be spaced to be 0.010″ to 0.500″ from each other. Further, each groove can have a depth D of 0.005″ to 0.040″, a width W of 0.005″ to 0.080″, a tip radius RT of 0.001″ to 0.040″, and a groove angle α of 0° to 120°. Further, the rake angle αR can range from −60° to +60°. 
     Also provided by the present invention are devices and methods of attaching soft tissue or grafts to implants. The soft tissue can be any type of soft tissue including tendons, cartilage, muscle, etc. that might be encountered in a surgical setting. The present invention also provides devices and methods for attaching grafts that allow for soft tissue ingrowth to implants. The present invention can allow attachment of soft tissue or a graft to an implant with minimal damage to the tissue or graft, providing a way for a tendon to attach to a hip stem, minimizing damage caused by tendon ingrowth regions to the graft or tendon, and providing an instrument to aid in holding and tensioning a graft during surgery. It should be noted, in the context of the present invention, that “a graft” and “a soft tissue” can be used interchangeably, with reference to either also encompassing reference to the other. 
     Referring now to  FIGS. 31-32 , another embodiment of an orthopaedic implant  1100  according to the present invention is shown. The orthopaedic implant  1100  includes an implant body  1102 , shown as a femoral hip implant, and an adjustable holder  1104 , shown as a cover plate, attached to the implant body  1102 . As can be seen, the implant body  1102  defines an attachment region  1106  on an outer surface  1108  of the implant body  1102  where a graft  1110  can be attached to the implant body  1102 . The attachment region  1106  can have rounded corners  1112  to produce low pressure on the graft  1110  when the graft  1110  is compressed to the attachment region  1106 . The attachment region  1106  can be formed of the same material as the rest of the implant body  1102  or can be formed of a porous ingrowth material, such as those previously described, that is configured to allow the graft  1110  to integrate with the ingrowth material and form a strong attachment to the attachment region  1106 . To compress the graft  1110  to the attachment region  1106 , the holder  1104  has a compression surface  1114  facing the attachment region  1106 . When the holder  1104  is moved from the position shown in  FIG. 31  to the position shown in  FIG. 32 , the compression surface  1114  can force the graft  1110  against the attachment region  1106  and provide anchoring of the graft  1110  to the implant body  1102 , either permanently or temporarily while the graft  1110  integrates with the attachment region  1106  to form a permanent attachment. To reduce the pressure exerted on the graft  1110  during compression, the holder  1104  can have an elongated curved shape and be tightened at a distal end  1116  of the holder  1104  such that the distal end  1116  of the holder  1104  is the area with the greatest compressive forces between the holder  1104  and the attachment region  1106 . The holder  1104  can be overlengthened, relative to the graft  1110 , such that no part of the graft  1110  is compressed between the distal end  1116  of the holder  1104  and the attachment region  1106 , allowing the holder  1104  to be pressed tightly against the implant body  1102  without compressing the graft  1110  in the area of the highest compression forces. The curved shape of the holder  1104  can also have rounded corners  1118  that approximately match the curvature of the rounded corners  1112  of the attachment region  1106  but have a slight deviation of 1-5% of the curvature away from the distal end  1116  so there is a small clearance formed between the compression surface  1114  and the attachment region  1106  when the holder  1104  is fully tightened to the implant body  1102 . Such a deviation in the curvature of the rounded corners  1118  of the compression surface  1114  away from the distal end  1116  can reduce the pressure exerted on the graft  1110  and decrease damage to the graft  1110  by decreasing the rapid change in stiffness between the portion of the graft  1110  that is compressed and the portion of the graft  1110  that is uncompressed. 
     Referring now to  FIG. 33 , a top view of the orthopaedic implant  1100  shown in  FIGS. 31-32  is shown. As can be seen, a channel  1120  can be formed in the holder  1104  where the graft  1110  will be located during compression. The channel  1120  allows for a reduced pressure across the length of the graft  1110  while still protecting the graft  1110  from outside contact and holding the graft  1110  to the attachment region  1106  of the implant body  1102 . 
     Referring now to  FIG. 34 , another embodiment of an orthopaedic implant  1200  according to the present invention is shown that includes an implant body  1202 , shown as a femoral hip stem, and an adjustable holder  1204  attached to the hip stem  1202 . As can be seen, a roller  1206  can be attached to the holder  1204  that allows for a graft  1208  to be wrapped around the roller  1206 . Wrapping the graft  1208  around the roller  1206  allows for a graft with an overly large length to be shortened and retained against an attachment region  1210  of the hip stem  1202 . In such a configuration, the graft  1208  can be tied around the roller  1206  to keep the graft  1208  attached to the roller  1206  and then compressed between the holder  1204  and the attachment region  1210 . 
     Referring now to  FIG. 35 , yet another embodiment of an orthopaedic implant  1300  according to the present invention is shown that includes an implant body  1302 , shown as a femoral hip stem, and an adjustable holder  1304  attached to the hip stem  1302 . The hip stem  1302  can have an ingrowth material  1306  attached to an attachment region  1308  of the hip stem  1302  and the holder  1304  can also have an ingrowth material  1310  that aligns with the ingrowth material  1306  of the hip stem  1302 . A graft  1312  can be placed between the two ingrowth materials  1306  and  1310  and connected to a ratcheting mechanism  1314  attached to the hip stem  1302  by wrapping the graft  1312  around the ratcheting mechanism  1314 . The ratcheting mechanism  1314  can then be turned to apply tension to the graft  1312  and tighten the graft  1312 , holding the graft  1312  in place between the two ingrowth materials  1306  and  1310 . Such a configuration allows the tension in the flexible graft  1312  to be conveniently adjustable during surgery. 
     Referring now to  FIG. 36 , yet another embodiment of an orthopaedic implant  1400  according to the present invention is shown that includes an implant body  1402 , shown as a femoral hip stem, and a holder  1404  attached to the hip stem  1402 . The implant body  1402  can have an attachment region  1406  with an ingrowth material  1408  and the holder  1404  can have a corresponding ingrowth material  1410  that is aligned with the ingrowth material  1408  of the attachment region  1406  so that when the holder  1404  is tightened against the hip stem  1402 , the two ingrowth materials  1408  can both be contacting a graft  1412  held between the holder  1404  and hip stem  1402 . The shape of the holder  1404  can be adjusted so that a pinch point  1414  is formed between the holder  1404  and the hip stem  1402  adjacent a distal end  1416  of the holder  1404  while a gap  1418  is formed between the holder  1404  and hip stem  1402  adjacent a proximal end  1420  of the holder  1404 . The pinch point  1414  can be where the greatest compressive forces are applied to the graft  1412  by the holder  1404  and hip stem  1402 , while the gap  1418  is where there are few, if any, compressive forces applied to the graft  1412  by the holder  1404  and hip stem  1402 . To better hold the graft  1412  between the holder  1404  and hip stem  1402 , a compliant material  1422  can be placed on the holder  1404  adjacent to the gap  1418  that will be deformed as the compliant material  1422  presses against the graft  1412  and hip stem  1402 . The compliant material  1422  can thus be a relatively soft and compressible material such as additional graft material, polyurethane, polyethylene, etc. that provides additional coverage and fixation of the graft  1412  with little increase in the compressive forces applied to the graft  1412  adjacent to the gap  1418 . 
     Referring now to  FIG. 37 , another embodiment of an orthopaedic implant  1500  according to the present invention is shown that includes an implant body  1502  and a collar  1504  affixed to the implant body  1502 . The collar  1504  can be affixed to the implant body  1502  by a press fit, adhesive, or any other suitable way of affixing the collar  1504  to the implant body  1502  such that the collar  1504  is not easily removed from the implant body  1502 . The collar  1504  can be formed of any biocompatible material and can also have an ingrowth material (not shown) in a region adjacent to where the collar  1504  is affixed to the implant body  1502 . The collar  1504  can allow for a graft  1506 , which can be formed of a synthetic or natural material, to be fixed to the collar  1504  to affix the graft  1506  to the implant body  1502 . The graft  1506  can be held between the collar  1504  and the implant body  1502 , if compression is desired, or attached to the collar  1504  without compressing the graft  1506  between the collar  1504  and the implant body  1502 . Optionally, an ingrowth pad  1508  formed of an ingrowth material can be connected to the implant body  1502  and the graft  1506  held against the ingrowth pad  1508  to allow the graft  1506  to infiltrate the ingrowth pad  1508  and form another attachment point to the implant body  1502 . 
     Referring now to  FIGS. 38A-38B , another embodiment of an orthopaedic implant  1600  is shown that includes an implant body  1602  and a collared graft  1604  attached to the implant body  1602 . The collared graft  1604  can be formed from a bifurcated graft  1606 , shown in  FIG. 38A , which has a first branch  1608  and a second branch  1610  connected to a main body  1612  of the bifurcated graft  1606 . The bifurcated graft  1606  can be, for example, a tendon or cartilage that is naturally bifurcated and taken from the body or a synthetic material shaped to include a bifurcation. To form the collared graft  1604  from the bifurcated graft  1606 , a portion of the second branch  1610  can be removed to form a collar region  1614  in the bifurcated graft  1606 , with a portion of the main body  1612  being connected to the collar region  1614  to form a collar  1616  of the collared graft  1604 , which is seen in  FIG. 38B . The collar  1616  can be formed prior to sliding over a stem  1618  of the implant body  1602  or formed by looping the portion of the main body  1612  around the stem  1618  and then connecting the portion to the collar region  1614  to form the collar  1616 , which will be looped around the stem  1618 . If desired, sutures  1622  can be used to reduce slippage between the collared graft  1604  and the implant body  1602 . 
     Referring now to  FIG. 39 , another embodiment of an orthopaedic implant  1700  according to the present invention is shown that includes an implant body  1702  having a series of openings  1704  formed therein and sutures  1706  looped through the openings  1704  to press a graft  1708  against the implant body  1702 . Prior to looping the sutures  1706  through the openings  1704 , the graft  1708  can be pulled in a tensioning direction, signified by arrow  1710 , by an instrument (not shown) to keep the graft  1708  taut prior to being affixed to the implant body  1702  by the sutures  1706 . While two suture loops  1706  and corresponding openings  1704  are shown, the number of openings  1704  can be varied, as desired, to be as few as one or more than two. It is also contemplated that the sutures  1706  can be replaced by surgical staples. 
     Referring now to  FIGS. 40A and 40B , yet another embodiment of an orthopaedic implant  1800  according to the present invention is shown that includes an implant body  1802  with a greater trochanter  1804 . As can be seen in  FIG. 40A , after implantation it can be discovered that the greater trochanter  1804  of the implant body  1802  does not have sufficient length to reach a tendon  1806  that is to be attached to the greater trochanter  1804 . Further stretching the tendon  1806  may cause the tendon  1806  to snap or be excessively strained, and thus is not a viable option. To allow for the tendon  1806  to be attached to the greater trochanter  1804 , and referring specifically to  FIG. 40B , an extension  1808  can be attached to the greater trochanter  1804  that effectively lengthens the greater trochanter  1804  and allows for the tendon  1806  to be attached to the implant body  1802 . The extension  1808  can be formed from the same material as the greater trochanter  1804 , to give similar attachment characteristics, or be a different material. The extension  1808  can also include any of the herein described features to allow the tendon  1806  to be attached to the extension  1808 . Further, the extension  1808  can be more flexible than the greater trochanter  1804  to decrease the gradient in stiffness between the tendon  1804  and the greater trochanter  1804 . 
     Referring now to  FIG. 41 , yet another embodiment of an orthopaedic implant  1900  according the present invention is shown that includes an implant body  1902  and a holder  1904  connected to the implant body  1902 . The implant body  1902  has an attachment region  1906 , similar to previously described implant bodies, and an ingrowth material  1908 , shown as an ingrowth pad, in the attachment region  1906 . The holder  1904  also has a pair of ingrowth materials  1910 , shown as pads, on opposite surfaces of the holder  1904  to contact interior surfaces  1912  of a graft  1914  attached to a tendon  1916 . The graft  1914  has an opening  1918  formed therein to partially split the graft  1914  into an interior portion  1920  that will be held between the holder  1904  and the attachment region  1906  and an exterior portion  1922  that will be on the exterior of the holder  1904 . The interior portion  1920  can thus contact multiple ingrowth pads  1908 ,  1910  and be compressed between the holder  1904  and the attachment region  1906  while the exterior portion  1922  also contacts an ingrowth pad  1910 . Such a configuration increases the amount of surface area of the graft  1914  that is in contact with ingrowth material and can hasten the attachment of the graft  1914  to the orthopaedic implant  1900 . 
     When ingrowth regions are attached to a surface of an implant, it is possible that the ingrowth regions will damage the attached graft due the ingrowth regions being raised relative to the surface. To reduce the risk of damage to an attached graft, and referring now to  FIG. 42 , an orthopaedic implant  2000  according to the present invention can have an implant body  2002  with a recess  2004  formed therein that is filled with a porous ingrowth material  2006  so the porous ingrowth material  2006  is flush with an outer surface  2008  of the implant body  2002 . The implant body  2002  can also have protruding regions  2010  that are rounded with a large radius leading into the area with the recess  2004  and porous ingrowth material  2006  to prevent large stress concentrations on a graft  2012  that is held against the porous ingrowth material  2006 . By having the ingrowth material  2006 , which can be a porous ingrowth pad, in the recess  2004  and flush with the outer surface  2008 , the risk that the graft  2012  will abrade against corners of the ingrowth pad  2006  and be damaged is reduced. It should be appreciated that while the gap between the graft  2012  and the porous ingrowth pad  2006  has been exaggerated in  FIG. 42  to show better detail, the graft  2012  will normally be in contact or close to contacting the porous ingrowth pad  2006  after implantation. 
     Referring now to  FIG. 43 , yet another embodiment of an orthopaedic implant  2100  according to the present invention is shown that includes an implant body  2102  with a recess  2104  formed therein and a porous ingrowth material  2106  placed in the recess  2104 . A holder  2108  can be connected to the implant body  2102  and also have a recess  2110  formed therein with a porous ingrowth material  2112  placed in the recess  2110 . A graft  2114  can be compressed between the holder  2108  and implant body  2102  so that the graft  2114  contacts both porous ingrowth materials  2106  and  2112 , which can lead to increased integration of the graft  2114  with the implant  2100  and reduced risk of wear due to abrasion with the porous ingrowth materials  2106  and  2112 . 
     Referring now to  FIG. 44 , yet another embodiment of an orthopaedic implant  2200  according to the present invention is shown that includes an implant body  2202  with a recess  2204  formed therein and a porous ingrowth material  2206  placed in the recess  2204 . The recess  2204  can be formed, for example, in a greater trochanter  2208  of the implant body  2202  and the porous ingrowth material  2206  can be a porous ingrowth pad placed in the recess  2204 . The orthopaedic implant  2200  can further include a holder, such as a plate, which is not shown to illustrate how a bifurcated graft  2210  with a first branch  2212  and a second branch  2214  can be held between the implant body  2202  and plate with the first branch  2212  and second branch  2214  placed on opposite sides of the porous ingrowth pad  2206 . The porous ingrowth pad  2206 , therefore, can be placed between the first branch  2212  and second branch  2214  to allow ingrowth of both branches  2212  and  2214  to the porous ingrowth pad  2206 . 
     While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.