JP6746743B2 - Patella drill guide and trial surgical instrument - Google Patents

Description

(Cross-reference of related applications)
Jennifer B. Co-pending U.S. patent application Ser. No. 13/630,935 (Attorney Docket No. 265 EP2350S, attorney docket No. 2265-2510S), entitled "ORTHOPAEDIC SURGICAL INSTRUMENT ASSEMBLY FOR IMPLANTING A PROSTHELA COMPONENT" by Clever et al. The name of the invention by Wallace et al. is "PATELLA DRILL GUIDE AND TRIAL SURGICAL INSTRUMENT HAVING AN ALIGNMENT BORE FORMED THEREIN AND METHOD No. 210/US Patent No. 210/30 US NUMBER 6/24, US USING THE 24 SAME No. 6/13, US USING THE 26 SAME No. 6/US 13 THE SAME No. 6/US 13 THE SAME No. , DEP6596USNP), and Jennifer B. The co-pending US patent application Ser. No. 13/630,965, entitled “METHOD FOR SURGICALLY IMPLANTING A PROSTHETIC PATELLA COMPONENT” by Cleveler et al. Is done. Each of these co-pending applications is assigned to the same assignee as the present application, filed concurrently therewith and incorporated herein by reference.

(Field of the invention)
The present disclosure relates generally to orthopedic surgical instruments, and more specifically to patella surgical instruments.

Arthroplasty is a well known surgical procedure in which lesioned and/or damaged natural joints are replaced with prosthetic joints. A typical knee prosthesis includes a tibial tray, a femoral component, and a polymer insert or bearing disposed between the tibial tray and the femoral component. In some cases, the knee prosthesis may also include a knee prosthesis component that is fixed to the posterior side of the surgically prepared patient's patella. To secure the prosthetic component to the patella, the orthopedic surgeon can prepare the natural patella to receive the prosthetic component by cutting the posterior aspect of the patient's natural patella. In use, the patella prosthesis component articulates with the femoral component during extension and flexion of the patient's knee.

According to one aspect, a patella drill guide and trial instrument includes a posterior trial bearing surface configured to articulate with a condylar surface of an artificial femoral component. The posterior trial bearing surface has a curved peak surface that defines the posterior surface of the patella drill guide and trial instrument. The patella drill guide and trial instrument also extends from the posterior trial bearing surface to the anterior surface through the patella drill guide and trial instrument and the anterior surface with some spikes extending outwardly therefrom. , Several drill guide holes, and.

In one embodiment, the posterior bearing surface is articulated with the medial trial articulating surface configured to articulate with the medial condylar surface of the artificial femoral component and the lateral condylar surface of the artificial femoral component. A configured outer trial articulation surface.

In one embodiment, the imaginary line bisects the anterior surface in the inward/outward direction and the center of each of the several spikes is located inside the imaginary line.

In one embodiment, some spikes include a central spike, an upper spike, and a lower spike. The upper/lower imaginary line bisects the front surface in the upper/lower direction, the center of the center spike is located on the upper/lower imaginary line, and the center of the upper spike is located above the upper/lower imaginary line. And the center of the lower spike is positioned below the upper/lower imaginary line.

The center spike may be longer than the top and bottom spikes.

Some drill guide holes may be counterbore holes.

The patella drill guide and trial instrument may further include a connecting slot positioned between the posterior trial bearing surface and the anterior surface. The connecting slot may be configured to receive the connecting tongue of the removable fastener to secure the patella drill guide and trial instrument to the removable fastener.

In one embodiment, the aft trial bearing surface and the anterior surface define a monolithic body. In another embodiment, the aft trial bearing surface and the anterior surface define a monolithic polymer body and a metal sleeve is inserted into each of several drill guide holes.

According to yet another aspect, a patella drill guide and trial instrument includes a posterior trial bearing surface configured to articulate with a condylar surface of a femoral prosthetic component. The posterior trial bearing surface has a curved peak surface that defines the posterior surface of the patella drill guide and trial instrument. The patella drill guide and trial instrument also include an anterior surface having a central spike and a number of peripheral spikes extending outwardly therefrom. The top/bottom imaginary line bisects the anterior surface in the top/bottom direction, with the center spike centered on the top/bottom imaginary line. The central spike may be longer than the peripheral spike. The patella drill guide and trial instrument further includes a number of drill guide holes extending through the patella drill guide and trial instrument from the posterior trial bearing surface to the anterior surface.

In one embodiment, the posterior bearing surface is articulated with the medial trial articulating surface configured to articulate with the medial condylar surface of the artificial femoral component and the lateral condylar surface of the artificial femoral component. A configured outer trial articulation surface.

In one embodiment, the imaginary line bisects the anterior surface in the inward/outward direction and the center of each of the several spikes is located inside the imaginary line.

In one embodiment, some of the peripheral spikes include an upper spike and a lower spike, with the center of the upper spike positioned above the upper/lower imaginary line and the center of the lower spike below the upper/lower imaginary line. Be positioned at.

In one embodiment, the inner/outer imaginary line bisects the anterior surface inward/outward and the center of each of the center spike, upper spike, and lower spike is positioned inside the inner/outer imaginary line. It

Some drill guide holes may be counterbore holes.

The patella drill guide and trial instrument may further include a connecting slot positioned between the posterior trial bearing surface and the anterior surface. The connecting slot may be configured to receive the connecting tongue of the removable fastener to secure the patella drill guide and trial instrument to the removable fastener.

In one embodiment, the aft trial bearing surface and the anterior surface define a monolithic body. In another embodiment, the aft trial bearing surface and the anterior surface define a monolithic polymer body and a metal sleeve is inserted into each of several drill guide holes.

In particular, the following drawings are referred to in the embodiments for carrying out the invention.
FIG. 6 is a perspective view of an orthopedic surgical instrument assembly showing a patella drill guide and trial instrument secured to a removable fastener. FIG. 2 is an enlarged perspective view of a patella drill guide and trial instrument of the orthopedic surgical instrument assembly of FIG. 1. FIG. 3 is a bottom elevation view of the patella drill guide and trial instrument of FIG. 2. FIG. 3 is a top elevational view of the patella drill guide and trial instrument of FIG. 2. FIG. 3 is a side elevational view of the patella drill guide and trial instrument of FIG. 2. 6 is a cross-sectional view of the patella drill guide and trial instrument taken along line 6-6 of FIG. 7 when viewed in the direction of the arrow. FIG. 3 is a side elevational view of a patella drill guide and trial instrument showing the instrument connector. 8 is a cross-sectional view of the patella drill guide and trial instrument taken along line 8-8 of FIG. 3 when viewed in the direction of the arrow. 2 is a side elevational view of the orthopedic surgical instrument assembly of FIG. 1. FIG. 2 is an enlarged fragmentary perspective view of the connector of the removable fastener of the orthopedic surgical instrument assembly of FIG. 1. FIG. FIG. 6 is a fragmentary top elevational view showing the patella drill guide and trial instrument secured to a removable fastener. FIG. 6 is a fragmentary perspective view showing a compression socket secured to a removable fastener. The perspective view of a compression socket. The side elevation view of a compression socket. The perspective view of an alignment handle. FIG. 6 is a perspective view showing an alignment handle secured to a patella drill guide and a trial instrument. FIG. 2 is a view similar to FIG. 1, but with an anatomical patella drill guide and trial instrument. FIG. 9 is a top perspective view of a modified domed patella component that may be implanted using the devices and methods described herein. FIG. 19 is a bottom perspective view of the modified domed patella component of FIG. 18. Front view of the patient's knee. Lateral view of the patient's knee. FIG. 6 is a surgical view showing alignment holes drilled in the apex of a patient's natural patella. FIG. 6 is a surgical view showing a generally flat surgically excised patella surface of a patient's patella. FIG. 6 is a surgical view showing a generally flat surgically excised patella surface of a patient's patella. FIG. 3 is a surgical diagram showing alignment of a patella drill guide and trial instrument 14 on a surgically resected patella surface of a patient's patella. FIG. 1 is a surgical view showing a patella drill guide and trial instrument 14 placed on a surgically resected patella surface of a patient's patella. FIG. 1 is a surgical view showing a patella drill guide and trial instrument 14 placed on a surgically resected patella surface of a patient's patella. FIG. 6 is a surgical diagram showing an alignment handle used to evaluate rotational positioning of the patella drill guide and trial instrument 14 during trial of the patellofemoral joint. FIG. 6 is a surgical diagram showing an alignment handle used to evaluate rotational positioning of the patella drill guide and trial instrument 14 during trial of the patellofemoral joint. FIG. 3 is a surgical view showing a tethered hole drilled into a patient's patella through a guide hole in a patella drill guide and trial instrument 14. FIG. 25 is a view similar to FIG. 24, but showing an anchoring hole drilled in the patient's patella. A patella clamp and compression socket used to clamp the patella component to the patient's patella during the bone cement polymerization process.

While various modifications and alternatives are possible to the concepts of the present disclosure, certain representative embodiments thereof are shown by way of example in the drawings and will be described in detail herein. However, it is not intended to limit the concept of the present disclosure to the specific form disclosed, and to the contrary, the present invention is intended to include the spirit and scope of the invention defined in the appended "Claims". It is to be understood that it is intended to cover all modifications, equivalents and alternatives included in.

The terms anterior, posterior, medial, lateral, superior, inferior, etc., which represent anatomical references, are used throughout the specification with respect to the orthopedic implants and surgical instruments mentioned herein, and with the patient's natural It can be used with respect to anatomy. These terms have their widely understood meanings both in the field of anatomy and in the field of orthopedics. The use of these anatomical reference terms in the specification and claims, unless otherwise stated, shall be consistent with their widely understood meanings.

With reference to FIG. 1, an orthopedic instrument assembly 10 includes a removable patella fastener 12 and a patella drill guide and trial instrument 14 configured to be secured to the patella fastener 12. The instrument assembly 10 is utilized to surgically prepare the patient's patella 16 for implantation of the artificial patella component 18, as described in further detail below (see FIGS. 18 and 19). To do this, the patella drill guide and trial instrument 14 serves as a trial instrument for trialing the patellofemoral joint and for drilling an anchoring hole into the flat, excised posterior surface of the patient's patella 16. Can be used as a drill guide. The surgeon may use the patella drill guide and trial instrument 14 to size and select a patella prosthetic component suitable for use with the patella of a particular patient.

As shown in FIG. 1, the patella fastener 12 of the instrument assembly 10 includes a pair of levers 20, 22 that are pivoted together with pivot pins 24. The proximal end of lever 20 includes an upper handle 26 and the distal end of lever 20 has a retention socket 28. The proximal end of the lever 22 includes the lower handle 30 and the distal end of the lever 22 has a connector 32 (see Figure 10). The lever 22 is a module whose design is such that the connector 32 is not integrally formed with the lower handle 30. The proximal end 34 of the connector 32 is captured within a slot 36 formed in a cylindrical housing 38. As shown in FIG. 9, the proximal end 34 of the connector 32 is substantially parallel to the distal end 42 of the lever 20 as the connector 32 translates upward and downward within the cylindrical housing 38. Connected to the distal end 40 of the lower handle 30 within the cylindrical housing 38 so as to be maintained in a relationship. A compression spring 44 (see FIG. 9) is positioned within the cylindrical housing 38 and exerts a spring bias on the proximal end 34 of the connector 32 to push the connector 32 away from the retention socket 28.

As the surgeon grasps or otherwise pushes the two handles 26, 30 towards each other, the levers 20, 22 pivot about the pin 24, thereby moving the connector 32 and the retention socket 28 toward each other. To move. When the surgeon releases the two handles 26, 30, the spring bias of the compression spring 44 pushes the connector 32 away from the retaining socket 28, thereby pivoting the levers 20, 22 about the pin 24 and the two handles. Move 26, 30 away from each other.

As can be seen in FIG. 9, the lever 22 has a number of ratchet teeth 46 formed therein. The button 48 is fixed to the lever 20 near its upper handle 26. The button 48 is moved so that the locking pole 50 engages the ratchet teeth 46 by sliding the button 48 toward the cylindrical housing 38 and sliding it in the opposite direction. The locking pole 50 is engaged so as to be disengaged from the ratchet teeth 46. When the locking pole 50 engages the ratchet teeth 46, the levers 20, 22 of the patella clamp 12 are locked and thus cannot move relative to each other. When the locking pole 50 is disengaged from the ratchet teeth 46, the levers 20, 22 of the patella clamp 12 are free to move relative to each other.

As can be seen in FIG. 1, in the illustrative embodiment described herein, the fastener retaining socket 28 is implemented as a ring 58 having a number of spikes 60 extending outwardly therefrom. To be done. When the instrument 14 is secured to the fastener 12, the spikes 60 face towards some of the spikes in the patella drill guide and trial instrument 14. In such an arrangement, the fastener spikes 60 cooperate with the patella drill guide and trial instrument 14 spikes to capture the patella 16 therebetween.

The patella fastener 12 may be constructed from medical grade metals such as stainless steel, cobalt chrome or titanium, although other metals or alloys may be used.

2-8, the patella drill guide and trial instrument 14 is shown in greater detail. As alluded to above, the patella drill guide and trial instrument 14 is used for conformity assessment during a surgical procedure in which an artificial patella component 18 is implanted into a patient's surgically prepared patella 16. In essence, the patella drill guide and trial instrument 14 is used to ensure proper sizing of the final patella component 18 (ie, the patella component 18 ultimately implanted in the patient's patella 16). As described in more detail below, the patella drill guide and trial instrument 14 also for drilling an anchoring hole in the patient's surgically prepared patella 16 to receive an anchoring peg of the patella component 18. It functions as a drill guide for guiding the drill bit used in (see FIG. 30).

As shown in FIGS. 2, 5, 7, and 8, the patella drill guide and trial instrument 14 is in the form of a curved peak surface that is configured to articulate with the condylar surface of the femoral prosthetic component 154. Includes a rear trial bearing surface 52 (see Figures 28 and 29). In particular, the posterior trial bearing surface 52 of the patella drill guide and trial instrument 14 includes an outer trial joint surface 54 and an inner trial joint surface 56. The trial joint surfaces 54, 56 are configured to articulate with the lateral condyle surface 172 and the medial condyle surface 174, respectively, of the femoral component 154. The femoral component 154 is configured to mimic the configuration of the patient's natural femoral condyle, and thus the lateral condyle surface 172 and the medial condyle surface 174 are configured in a manner that mimics the condyle of the natural femur ( For example curved). The lateral condyle surface 172 and the medial condyle surface 174 are spaced apart from each other, thereby defining a trochlear groove 176 therebetween.

As can be seen in FIGS. 3, 5, 7, and 8, the patella drill guide and trial instrument 14 also has a flattened member having some fixation members, such as spikes 64, extending anteriorly therefrom. Includes a front surface 62. The spikes 64 are configured to be inserted into a posterior surface (not shown) of a surgically prepared natural patella of a patient. Thus, the posterior trial bearing surface 52 of the patella drill guide and trial instrument 14 faces toward the femoral component 154, which causes the posterior trial bearing surface 52 to flex and extend the patient's knee during the patellofemoral trial procedure. In between, it allows articulation with the femoral condyle surfaces 172, 174.

As shown in FIGS. 3, 5, 7, and 8, in an exemplary embodiment described herein, the spike 64 of the patella drill guide and trial instrument 14 is centered in the superior/inferior direction. Includes spike 66. This is shown geometrically in FIG. 3 with the phantom line 72 bisecting the anterior surface 62 of the patella drill guide and trial instrument 14 in an up/down direction. As can be seen in the figure, the center of the central spike 66 is located on the imaginary line 72, thereby centering the central spike 66 in the up/down direction. The spike 64 of the patella drill guide and trial instrument 14 also includes a pair of peripheral spikes 68, 70. As can be seen in FIG. 3, the center of the peripheral spike 68 is located in the upper half of the anterior surface 62 of the patella drill guide and trial instrument 14 (ie, above the imaginary line 72) and the other peripheral edge. The spike 70 is located on the lower half of the anterior surface 62 of the patella drill guide and trial instrument 14 (ie, below the imaginary line 72).

As can be seen in FIG. 3, in the exemplary embodiment described herein, each of the spikes 64 is located medially on the anterior surface 62 of the patella drill guide and trial instrument 14. In particular, the center of each of the central spike 66 and the peripheral spikes 68, 70 are located in the medial half of the anterior surface 62 of the patella drill guide and trial instrument 14, respectively. This is shown geometrically in FIG. 3, with the phantom line 74 bisecting the anterior surface 62 of the patella drill guide and trial instrument 14 inward/outward. The center of each of the central spike 66 and the pair of peripheral spikes 68, 70 is positioned inside the imaginary line 74 (ie, between the imaginary line 74 and the innermost edge of the patella drill guide and trial instrument 14). Be done). Such medial positioning of spikes 64 allows for fixation to less rigid (ie, softer) bone tissue, which is generally present on the medial surface of patella 16.

As can be seen in FIGS. 5, 7, and 8, central spike 66 is longer than both peripheral spikes 68, 70. In this way, rotational positioning of the patella drill guide and trial instrument 14 may be accomplished prior to its fixation in its final position on the resected posterior surface of the patient's patella 16. In particular, the surgeon first inserts the tip of the central spike 66 into the resected posterior surface of the patient's patella 16 and then its central axis defined by the central spike 66, as described in further detail below. The rotational position of the patella drill guide and trial instrument 14 may be altered by rotating it about the ablated posterior surface of the patient's patella 16 about. When the patella drill guide and trial instrument 14 is rotated to the desired alignment position, the instrument 14 causes the peripheral spikes 68, 70 to engage the bone tissue of the resected patella surface, thereby preventing further rotation and Of the patella 16 may be pressed against the resected posterior surface of the patient's patella 16 to maintain the patella drill guide and trial instrument 14 in its desired rotational position relative to the excised posterior surface.

The body of the patella drill guide and trial instrument has a number of drill guide holes 76 formed therein. The drill guide hole 76 extends through the entire thickness of the body of the patella drill guide and trial instrument. That is, the posterior end 78 of the drill guide hole 76 opens into the posterior trial bearing surface 52 of the patella drill guide and trial instrument 14 and the opposite anterior end 80 of the drill guide hole 76 opens into the instrument anterior surface 62. .. The guide hole 76 serves as a drill guide to drill an anchoring hole 180 in the patient's surgically prepared patella 16 and to guide a drill bit 84 used to receive an anchoring peg of the patella component 18. It works (see Figures 30 and 31). Thus, the size and location of each of the drill guide holes 76 matches the size and location of the anchoring pegs 182 of the patella component 18 (see FIG. 19).

As best seen in FIGS. 2, 4, and 8, in the exemplary embodiment described herein, each of the drill guide holes 76 is counterbored. Thus, the drill guide holes 76 have a larger diameter at their posterior ends 78 than at their anterior ends 80, thereby defining a shoulder 82 therebetween. The shoulder 82 acts as a depth stop to ensure that the surgical drill bit 84 used to drill the anchoring hole 182 in the patient's patella 16 drills to the desired depth. In particular, as can be seen in FIG. 30, a surgical drill bit 84 used to drill an anchoring hole in a patient's patella 16 has an annular collar 86 positioned over the upper end of the cutting flute 88 of the bit. including. During use, the drill bit 84 may be threaded through one of the drill guide holes 76 until the underside of the collar 86 reaches the bottom surface or otherwise engages the shoulder 82 of the counterbore guide hole 76. May be advanced into the bone tissue of the patella 16.

As best shown in FIGS. 1-3, the patella drill guide and trial instrument 14 has an alignment bore 90 formed therein. Similar to the drill guide holes 76, the alignment bore 90 extends through the entire thickness of the body of the patella drill guide and trial instrument. That is, the posterior end 92 of the alignment bore 90 opens into the posterior trial bearing surface 52 of the patella drill guide and trial instrument 14, and the opposite anterior end 94 of the alignment bore 90 opens into the slot 102 of the instrument connector.

Alignment bore 90 acts as a visible alignment guide to allow the surgeon to align the cusp of patella drill guide and trial instrument 14 with the patient's natural patella 16 anterior location prior to resection of patella 16. To enable. In particular, the curved peak surface tip 96 of the posterior trial surface 52 defines the posterior point 98 of the patella drill guide and trial instrument 14. Alignment bores are formed (ie, open) at the tips 96 of the aft trial surface 52. As described in more detail below, the surgeon may drill (eg, drill) into the apex of the patient's natural patella 16 prior to resection. The holes are drilled to a depth greater than the thickness of the bone removed during the patella resection. As such, the shallow holes or depressions are still visible in the flat surgically excised patella surface after bone removal. The surgeon may align the alignment bore 90 with this remaining hole in the patella to align the cusp of the patella drill guide and trial instrument 14 with the position in front of the cusp of the patient's natural patella 16.

As can be seen in FIGS. 2-4 and 6, the alignment bore 90 has a diameter that is smaller than the respective diameter of the drill guide holes 76. As such, surgical drill bit 84 cannot be inadvertently passed through alignment bore 90.

As alluded to above, the patella drill guide and trial instrument 14 may be selectively secured to the removable patella fastener 12. In that regard, the patella drill guide and trial instrument 14 includes a female connector shape configured to receive the male shape of the connector 32 of the patella clamp 12 (see FIG. 10). Specifically, the body of the patella drill guide and trial instrument 14 has a connection slot 102 formed therein. As can be seen in FIGS. 7 and 8, the connecting slot 102 is positioned between the aft trial bearing surface 52 and the aft surface 62. The connecting slot 102 is shaped and dimensioned to receive the connecting tongue 104 of the connector 32 of the patella fastener. As can be seen in FIGS. 10 and 11, the connecting tongue 104 includes a tip 106 that extends outwardly from the rounded surface of the body of the connector 32. As can be seen in FIG. 6, the connecting slot 102 of the patella drill guide and trial instrument 14 has a similar shape and is sized and shaped to receive the tip 106 of the connecting tongue 104 of the patella clamp. And includes a tip recess 108.

As can be seen in FIGS. 6 and 8, the upper sidewall 110 that defines the upper surface of the connection slot 102 has a recess 112 defined therein. In the exemplary embodiment described herein, the locking recess 112 is generally hemispherical in shape. The locking recess 112 is sized and positioned to receive the locking mechanism of the patella clamp connector 32 and secure the patella clamp 12 to the patella drill guide and trial instrument 14. In one embodiment, the locking mechanism is implemented as a bias plunger positioned on the tip 106 of the connecting tongue 104 of the patella fastener. In certain embodiments, the biased plunger may be implemented as a spring biased ball plunger 114. When the patella clamp connector 32 is inserted into the connection slot, the ball plunger 114 is against the spring bias by the upper sidewall 110 until it reaches a position where the ball plunger 114 moves into the locking recess 112 due to the spring bias. Pushed down. When the ball plunger 114 is positioned in the lock recess 112, by pushing the ball plunger 114 downward from the lock recess 112, sufficient force is applied to pull the two components apart, allowing the patella clamp 12 to move the patella drill guide and. The patella clamp 12 is rigidly secured to the patella drill guide and trial instrument 14 until separated from the trial instrument 14.

As can be seen in FIG. 6, the alignment bore 90 of the patella drill guide and trial instrument 14 passes through the distal recess 108 of the connection slot 102. As described above, when the patella clamp 12 is secured to the patella drill guide and trial instrument 14, the tip 106 of the connecting tongue 104 of the patella fastener is positioned in the tip recess 108 of the connecting slot 102. When so positioned, the tip 106 of the patella clamp connecting tongue 104 blocks the alignment bore 90 or otherwise prevents movement therethrough, as shown in FIG. More specifically, when the tip 106 of the patella clamp connecting tongue 104 is positioned in the tip recess 108, a drill bit or other instrument prevents passage through the alignment bore 90.

The patella drill guide and trial instrument 14 may be provided in a number of different sizes to accommodate the anatomy needs of a given patient. For example, in the illustrative embodiment described herein, the patella drill guide and trial instrument 14 is implemented in five different medial/lateral lengths to mimic various dimensions of the artificial patella component 18. (Eg, 29 mm, 32 mm, 35 mm, 38 mm, and 41 mm).

In the exemplary embodiments described herein, the patella drill guide and trial instrument 14 allows for a smooth articulation between the patella drill guide and trial instrument 14 and the femoral component 154. It is realized as a monolithic metal body composed of a compatible metal. Examples of such biocompatible metals include stainless steel, cobalt chrome, or titanium, although other metals or alloys may be used. The patella drill guide and trial instrument 14 may be implemented as a monolithic polymer trial instrument. As such, the patella drill guide and trial instrument 14 may be made of any suitable medical grade polymeric metal. Examples of such polymeric materials include polyethyl ethyl ketone (PEEK), ultra high molecular weight polyethylene (UHMWPE), or acetals. In such an embodiment, the monolithic polymer trial may include a metal insert (eg, sleeve) positioned in the drill guide hole 76.

As can be seen in FIGS. 12-14, the removable fastener 12 may be secured to the compression socket 120. The compression socket 120 may be used to apply clamping pressure to the patella component 18 when secured in place on the patient's resected patella 16. The compression socket 120 includes a base in the form of a ring 122. The ring 122 has a ring-shaped compressible cushion 124 secured thereto. The compression cushion 124 is deformable to engage the posterior bearing surface 188 of the patella component 18 by pushing it toward the patella 16 when a tightening force is applied by use of the patella fastener 12. Composed of materials and functions.

The compression socket 120 includes a female connector shape similar to that of the patella drill guide and trial instrument 14 and, as a result, is configured to receive the male shape of the connector 32 of the patella clamp 12 (see FIG. 12). .. Specifically, the ring 122 of the compression socket 120 has a connection slot 126 formed therein. As can be seen in FIGS. 13 and 14, the connecting slot 126 is shaped and dimensioned to receive the connecting tongue 104 of the connector 32 of the patella fastener. As can be seen in FIG. 12, the tip 106 of the connecting tongue 104 allows the spring biased ball plunger 114 to engage the annular wall 128 of the ring 122 to secure the clamp 12 to the compression socket 120. In addition, it extends beyond the inner annular wall 128 of the compression socket ring 122. In particular, when the patella clamp connector 32 is inserted therethrough into the compression socket connection slot 126, the ball plunger 114 exits the connection slot 126 when the ball plunger 114 moves upward due to its spring bias. Is pushed downwards against its spring bias by the upper sidewall 130 until it enters the center of the ring. When the ball plunger 114 is so positioned, sufficient force is applied to pull the two components apart by pushing the ball plunger 114 downward and back into the connecting slot 126, which causes the patella fastener 12 to move. The patella fastener 12 is rigidly secured to the compression socket 120 until it is separated from the compression socket 120.

The ring 122 of the compression socket 120 may be realized as a monolithic metal body composed of a biocompatible metal such as stainless steel, cobalt chrome, or titanium, although other metals or alloys may be used. Ring 122 may be implemented as a monolithic polymer trial instrument constructed of any suitable medical grade polymeric material such as polyethylethylketone (PEEK), ultra high molecular weight polyethylene (UHMWPE), or acetal. The compression cushion 124 may be constructed of any suitable medical grade compressible material such as silicone.

As can be seen in FIGS. 15 and 16, the patella drill guide and trial instrument 14 may be secured to the alignment handle 140. The use of the alignment handle 140 allows the surgeon to assess the rotational alignment of the patella drill guide and trial instrument 14 when articulating within the trochlear groove of the femoral component 154 during a patellofemoral joint trial. .. The alignment handle 140 includes a relatively flat elongated flange 142 having a connector 144 formed at one end thereof. The alignment handle connector 144 is identical to the patella clamp connector 32 so that it mates with the patella drill guide and trial instrument 14 connector in the same manner as the patella clamp 12. Thus, the alignment handle connector 144 has a connecting tongue 146 that includes a tip 148 that extends outwardly from the rounded surface of the body of the connector 144. The connecting tongue 146 and its tip 148 are received in the connecting slot 102 of the patella drill guide and trial instrument 14 in a manner similar to a similar structure of the patella clamp connector 32.

Similarly, the alignment handle connector 144 includes a locking mechanism that secures the alignment handle 140 to the patella drill guide and trial instrument 14. In one embodiment, the locking mechanism is implemented as a bias plunger positioned on the tip 148 of the connector 144 of the alignment handle. In certain embodiments, the biased plunger may be implemented as a spring biased ball plunger 152. The ball plunger 152 is captured in the locking recess 112 of the connection slot 102 of the patella drill guide and trial instrument 14 and causes the alignment handle 140 to engage the patella drill guide and trial in the same manner as described above for attachment of the patella fastener 12. It can be fixedly secured to the instrument 14. By pushing the ball plunger 152 downwards out of the lock recess 112, sufficient force is applied to pull the two components apart, until the alignment handle 140 is separated from the patella drill guide and trial instrument 14, the alignment handle 140 is It remains fixed to the patella drill guide and trial instrument 14 by the ball plunger 152.

Referring now to FIG. 17, another embodiment of the patella drill guide and trial instrument 14 is shown. In particular, the patella drill guide and trial instrument 14 of FIGS. 1-9 is implemented as a trial instrument that mimics a modified domed patella component, while the patella drill guide and trial instrument 14 mimics other types of patella components. May be realized as: For example, as shown in FIG. 17, the patella drill guide and trial instrument 14 is implemented to mimic a “matching” or “anatomical” patella component designed to match the condylar surface of the femur. May be. The domed patella component allows for greater movement between the patella component and the femoral component of the knee joint prosthesis, while the anatomical patella component is more constrained relative to the femoral component. As shown in FIG. 17, such an “anatomical” patella drill guide and trial instrument 14 is implemented with functionality similar to that described above with respect to the “modified domed” patella drill guide and trial instrument 14. Can be done.

Referring now to FIGS. 20-32, a patient's patella 16 is surgically implanted to implant the artificial patella component 18 of FIGS. 19 and 20 using various instruments described herein with respect to FIGS. A surgical procedure to be prepared is shown. The surgical procedure may begin with pre-operative planning, and in particular, CT scans or other types of pre-operative images may be obtained to plan the location and orientation of the patella component 18. Upon completion of the pre-operative plan, the patient's soft tissue is dissected and retracted to allow access to the knee. Complete exposure of the patient's joints is typically accomplished to expose the patient's femur 150 and tibia 152 in addition to the patella 16 (see Figures 20 and 21).

In addition to implanting the patella component 18, the surgical procedure also replaces the patient's natural distal femur 150 with an artificial femoral component 154 and replaces the patient's natural proximal tibia 152 with a tibial tray 156 and tibial bearing 158. (See Figures 28 and 29). However, the surgical implantation of femoral component 154, tibial tray 156, and tibial bearing 158 has not been detailed herein. Furthermore, the patella 16 is shown in its anatomical position relative to the femur 150 and tibia 152 in FIGS. 20 and 21, but the patella 16 is shown in the remaining drawings (FIGS. 28 and 28) for clarity of explanation. (Except 29) are shown separated from their anatomical position.

Prior to resection of the patient's patella 16 as shown in FIG. 22, the surgeon first creates alignment features on the apex 160 of the posterior surface 162 of the patella. In particular, the surgeon may drill 166 a hole 164 in the apex 160 of the posterior surface 162 of the patient's natural patella 16 prior to resection. As can be seen in the comparison of FIGS. 22 and 23, the alignment hole 164 is drilled to a predetermined depth that is deeper than the thickness of the bone removed during the patella resection. As such, the holes 164 (or slight depressions depending on the depth of the drill) are still visible in the flat surgically excised patella surface 170 following bone removal.

Once the alignment hole 164 is drilled into the posterior surface 162 of the patient's natural patella 16, the surgeon may then resect the patient's natural patella 16. Specifically, the surgeon uses a resection guide (not shown) and a bone saw (also not shown) to have a generally flat surgical resection on which the patella component 18 is subsequently implanted. A patella surface 170 may be created. Although a number of different instruments and methods can be used to excise a patient's natural patella 16, an illustrative instrument and method for doing this is the title of the invention, "Patella Orthopedic Surgical Method", June 2012. It is described in co-pending co-pending US patent application Ser. No. 13/533,607, filed 26th.

As alluded to above and shown in FIGS. 23 and 24, the alignment holes 164 drilled by the surgeon prior to resection are still visible at the flat surgically resected patella surface 170 following bone resection. appear. Depending on the depth of the drilling procedure utilized to form the alignment hole 164, it may appear as a slight depression in the surgically resected patella surface 170.

Once the resection of the patient's natural patella 16 is complete, the surgeon determines the appropriate size of the patella component 18 for implantation on the surgically resected patella surface 170. To do this, the surgeon uses a patella drill guide and trial instrument 14. Specifically, as further detailed herein, the patella drill guide and trial instrument 14 is secured to the patient's surgically resected patella surface 170 to function as both a sizing trial and drill guide. May be done. To do this, the surgeon selects the first one of the different sizes of the patella drill guide and trial instrument 14 that he estimates is the appropriate size for the patient. As shown in FIGS. 25 and 26, the surgeon then positions the selected patella drill guide and trial instrument 14 on the surgically excised patella surface 170 and evaluates the coverage. Specifically, the surgeon drilled the alignment bore 90 of the initially selected patella drill guide and trial instrument 14 into the flat surgically excised patella surface 170 (before excision) by the surgeon. Align with the alignment hole 164. To do this, the surgeon visualizes the drilled alignment holes 164 in the flat surgically excised patella surface 170 through the alignment bores 90 in the instrument, and the drilled alignment holes 164 and the instrument. Adjust the position of the selected patella drill guide and trial instrument 14 so that the alignment bores 90 are aligned with each other. Once aligned in this manner, the surgeon may then evaluate the coating of the selected patella drill guide and trial instrument 14. If the surgeon determines that the selected patella drill guide and trial instrument 14 is not the proper size, then the initial patella drill guide and trial instrument 14 is removed and a patella drill guide and trial instrument 14 having different dimensions is selected. Aligned and evaluated on the surgically excised patella surface 170.

Once the appropriately sized patella drill guide and trial instrument 14 is determined, the surgeon secures the patella drill guide and trial instrument 14 to the surgically excised patella surface 170. To do this, the surgeon aligns the alignment bore 90 of the selected patella drill guide and trial instrument 14 with the drilled alignment hole 164 of the flat surgically excised patella surface 170. Position the patella drill guide and trial instrument 14 (ie, patella component 18) in the desired location and orientation for final implantation. Once so positioned, the spikes 64 of the patella drill guide and trial instrument 14 face downward toward the surgically resected patella surface 170. As can be seen in FIG. 26, when aligned over the surgically resected patella surface 170, the peripheral spikes 68, 70 of the patella drill guide and trial instrument 14 are medial to the center of the patella 16. Be positioned at.

As can also be seen in FIG. 26, when the patella drill guide and trial instrument 14 was pushed toward the patella 16, the central spike 66, which was longer than both the peripheral spikes 68, 70, was first surgically excised. Contact the patella surface 170. In this way, rotational positioning of the patella drill guide and trial instrument 14 can be accomplished prior to its fixation in its final position on the surgically resected patella surface 170. In particular, the surgeon may first insert the tip of the central spike 66 into the surgically resected patella surface 170 of the patient's patella 16. The surgeon then adjusts the rotational position of the patella drill guide and trial instrument 14 by rotating it relative to the surgically excised patella surface 170 about its central axis defined by the central spike 66. obtain.

As shown in FIG. 27, when the patella drill guide and trial instrument 14 is rotated to the desired alignment position, the patella drill guide and trial instrument 14 displays the peripheral spikes 68, 70 on the surgically excised patella surface. It may be pushed into the surgically resected patella surface 170 to engage and seat the bone tissue of 170. Doing this prevents further rotation of the patella drill guide and trial instrument 14 and maintains it in its desired position relative to the surgically resected patella surface 170 of the patient's patella 16.

Of course, the surgeon may push the patella drill guide and trial instrument 14 into the bone tissue of the surgically resected patella surface 170 by the application of manual acupressure alone. However, in some cases it may be necessary to utilize additional force to fully seat the patella drill guide and trial instrument 14 on the surgically resected patella surface 170. In such a case, the surgeon places the removable fastener 12 on the patella drill guide and trial instrument 14 and uses the fastener 12 to pull the spike 64 of the instrument on the surgically resected patella surface 170. A tightening force that pushes into the bone tissue may be applied to fully seat the patella drill guide and trial instrument 14.

Once the patella drill guide and trial instrument 14 is placed over the surgically excised patella surface 170, the surgeon may then perform trials of the patellofemoral joint to assess sizing and positioning. To do this, the surgeon first installs an alignment handle 140 on the patella drill guide and trial instrument 14. The use of the alignment handle 140 allows the surgeon to assess the rotational alignment of the patella drill guide and trial instrument 14 when articulating within the trochlear groove of the femoral component 154 during a patellofemoral joint trial. .. To secure the alignment handle 140 to the patella drill guide and trial instrument 14, the surgeon inserts the handle connector 144 into the patella drill guide and trial instrument 14 connection slot 102. To do this, the handle's ball plunger 152 is captured in the locking recess 112 of the connecting slot 102 of the patella drill guide and trial instrument 14 to secure the alignment handle 140 to the patella drill guide and trial instrument 14.

Once the alignment handle 140 is in place, the surgeon then positions the patella so that its posterior trial bearing surface 52 is positioned to articulate within the trochlear groove 176 of the femoral condyle surfaces 172, 176 of the femoral component 154. The drill guide and trial instrument 14 can be positioned. The surgeon may then manipulate the patient's leg to make a trial articulation of the patellofemoral joint. In doing this, the surgeon uses the alignment handle 140 as a visual indicator of the rotational alignment of the patella drill guide and trial instrument 14 as it articulates in the trochlear groove 176 of the femoral component 154. Good. Specifically, as can be seen in FIG. 28, when the medial edge of the patella drill guide and trial instrument 14 (ie, the edge in which the connection slot 102 is formed) is properly aligned, the alignment handle 140 will , Extend outward in a direction generally perpendicular to the long axes of the femur and tibia. That is, it extends outward in a generally inward/outward direction.

However, if the rotational positions of the patella drill guide and trial instrument 14 are not properly aligned, the alignment handle will extend outwardly at a skewed angle, as shown in FIG. That is, if not properly aligned, the alignment handle 140 extends outwardly in a direction that is not generally perpendicular to the long axis of the femur and tibia. As such, the alignment handles 140 are not aligned in a generally medial/lateral direction.

Based on the above, the surgeon may evaluate the rotational position and alignment of the patella drill guide and trial instrument 14 through the trial articulation of the patellofemoral joint by monitoring the position of the alignment handle 140. At any point during the trial procedure, if the alignment handle 140 does not maintain the desired angle with respect to the long axis of the femur and tibia (ie, does not extend in a generally medial/lateral direction), the surgeon may Correct manipulations may be performed regarding the positioning of the drill guide and trial instrument 14 to improve its rotational positioning.

Once the surgeon has completed the trial arthroplasty of the patellofemoral joint and made any necessary adjustments to the position of the patella drill guide and trial instrument 14, the surgeon then makes several adjustments to the surgically resected patella surface 170. The mooring holes 180 may be drilled. The anchoring holes 180 are sized and positioned to receive the anchoring pegs 182 of the patella component 18 (see Figure 19). To do this, the surgeon first secures the removable fastener 12 to the patella drill guide and trial instrument 14 by advancing the fastener connector 32 into the connecting slot 102 of the patella drill guide and trial instrument 14. .. To do this, the ball plunger 114 of the handle is captured in the locking recess 112 of the connecting slot 102 of the patella drill guide and trial instrument 14 to secure the patella fastener 12 to the patella drill guide and trial instrument 14.

The surgeon then grasps the fastener handles 26, 30 towards each other, thereby moving the patella drill guide and trial instrument 14 and the retention socket 28 towards each other, tightening the patella 16 therebetween. Once the patella 16 is secured by the fastener 12, the surgeon may now drill the anchoring holes 180. To do this, the surgeon inserts the rotating tip 184 of the surgical drill bit 84 through the guide hole 76 through the anterior surface 62 of the instrument and into the bone tissue of the surgically resected patella surface 170. As such, it is advanced through the patella drill guide and trial instrument 14 into the opening formed in the posterior trial bearing surface 52 of one of the drill guide holes 76. The surgeon inserts the drill bit 84 into the patella 16 until the lower surface of the collar 86 of the bit reaches the bottom or otherwise engages the depth stop (ie, shoulder 82) of the counterbore guide hole 76. Keep moving forward in. The surgeon then drills the remaining anchor holes 180 in a similar manner.

As noted above, the dimensions and locations of each of the drill guide holes 76 match the dimensions and location of the anchoring pegs 182 of the patella component 18 (see FIG. 19). Thus, as the surgeon advances the surgical bit 84 of the drill through each of the guide holes 76, the surgically excised patella surface 170 is prepared for implanting the patella component 18 as shown in FIG. To be done.

Of course, during such drilling of the anchoring hole 180, the diameter of the bore is smaller than the diameter of the bit, so the surgeon will need to insert the surgical bit 84 of the drill through the alignment bore 90 of the patella drill guide and trial instrument 14. Can't move forward. Further, as described above, when the patella clamp 12 is secured to the patella drill guide and trial instrument 14, the tip 106 of the patella clamp connecting tongue 104 is positioned in the tip recess 108 of the instrument connecting slot 102. It When so positioned, the tip 106 of the patella clamp connecting tongue 104 blocks the alignment bore 90 or otherwise prevents movement therethrough, as shown in FIG. Thus, the drill bit 84 used to drill the mooring hole 180 cannot be advanced through the alignment bore 90 due to the smaller diameter of the bore, as well as other instruments. The presence of the tip 106 of the patella clamp connecting tongue 104, which is positioned in the tip recess 108 of the instrument connecting slot 102, does not allow it to pass through the alignment bore 90 to the surgically excised patella surface 170.

Of course, in some instances, the surgeon may wish to utilize the patella drill guide and trial instrument 14 to drill the anchoring hole 180 without using the patella clamp 12. In such cases, the surgeon may maintain the patella drill guide and trial instrument 14 with only the application of acupressure.

Referring now to FIG. 32, when an anchoring hole 180 is drilled into the surgically resected patella surface 170, the surgeon selects the appropriately dimensioned patella component 18 (ie, through trials as described above). A component 18 having the defined dimensions (ie, medial/lateral length) is implanted in the patient's patella 16. The surgeon may first apply bone cement to the anterior surface 190 of the patella component 18. The patella component 16 is then positioned over the surgically excised patella surface 170 such that the component's anchoring pegs 182 align with their respective anchoring holes 180. The patella component 12 may then be advanced such that the anchoring pegs 182 are received within the anchoring holes 180 and the anterior surface 190 is positioned in contact with the surgically resected patella surface 170.

The removable fastener 12 may then be secured to the compression socket 120 by inserting the fastener connector 32 into the socket connection slot 126. The compression socket 120 may then be used to apply tightening pressure to the patella component 18 when secured in place on the patient's resected patella 16. That is, the compression socket 120 and the fastener 12 may be used to maintain the clamping pressure on the patella component 18 as the bone cement polymerizes. To do this, the ring-shaped compressible cushion 124 of the compression socket 120 is positioned over the posterior bearing surface 188 of the patella component 18. The surgeon then grasps the fastener handles 26, 30 toward each other, thereby moving the compression socket 120 and the retention socket 28 toward each other. During such movement, the compressible cushion 120 of the compression socket 120 is advanced into contact with the posterior bearing surface 188 of the patella component 16. The patella component 16 is seated within the concave surface 192 of the compressible cushion 120 and thereby secured (see FIG. 14), excising the patella component 16 until polymerization is complete and the patella component 16 is secured therein. The patella 16 is tightened tightly. During the polymerization process, the surgeon may slide the patella clamp button 48 forward to lock the clamp 12 in its current position.

Although the present disclosure has been illustrated and described in detail in the drawings and the above description, such illustration and description should be regarded as illustrative in nature and not restrictive. It will be appreciated that the exemplary embodiments are shown and described only and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.

The present disclosure has many advantages based on the various features of the methods, devices, and systems described herein. It is noted that alternative embodiments of the methods, apparatus, and systems of the present disclosure do not include all of the features described herein, but benefit from at least some of the advantages of those features. See. A person of ordinary skill in the art will readily be able to uniquely implement methods, apparatus and systems within the spirit and scope of the present disclosure as defined in the claims, which incorporate one or more features of the invention. It is possible to carry out.

Embodiments
(1) A patella drill guide and a trial instrument,
A posterior trial bearing surface configured to articulate with a condylar surface of an artificial femoral component, the posterior trial bearing surface comprising a curved peak surface defining a posterior surface of the patella drill guide and trial instrument. When,
A front surface having a number of spikes extending outwardly therefrom, and
A number of drill guide holes extending from the posterior trial bearing surface to the anterior surface through the patella drill guide and trial instrument;
A patella drill guide and trial instrument comprising.
(2) The rear bearing surface is
A medial trial articulation surface configured to articulate with the medial condyle surface of the artificial femoral component;
A lateral trial articulating surface configured to articulate with a lateral condylar surface of the artificial femoral component,
A patella drill guide and trial instrument according to embodiment 1, comprising:
(3) An imaginary line bisects the front surface in the inward/outward direction,
The patella drill guide and trial instrument according to embodiment 1, wherein the center of each of the several spikes is positioned inside the imaginary line.
(4) The some spikes include a center spike, an upper spike, and a lower spike,
An up/down imaginary line bisects the front surface in the up/down direction,
The center of the central spike is located on the upper/lower imaginary line,
The center of the upper spike is positioned above the upper/lower imaginary line,
The patella drill guide and trial instrument according to embodiment 1, wherein the center of the lower spike is positioned below the upper/lower imaginary line.
(5) The patella drill guide and trial instrument according to embodiment 4, wherein the central spike is longer than the upper spike and the lower spike.

(6) An inner/outer imaginary line bisects the front surface in the inner/outer direction,
The patella drill guide and trial instrument according to embodiment 5, wherein the centers of each of the central spike, the upper spike, and the lower spike are positioned inside the medial/lateral imaginary line.
(7) The patella drill guide and trial instrument according to embodiment 1, wherein the some drill guide holes are counterbore holes.
(8) further comprising a connecting slot positioned between the posterior trial bearing surface and the anterior surface, the connecting slot securing the patella drill guide and trial instrument to a removable fastener. The patella drill guide and trial instrument of embodiment 1, configured to receive the connecting tongue of the removable fastener.
(9) The patella drill guide and trial instrument according to embodiment 1, wherein the posterior trial bearing surface and the anterior surface constitute a monolithic body.
(10) The patella drill guide of embodiment 1, wherein the posterior trial bearing surface and the anterior surface comprise a monolithic polymer body and further comprise a metal sleeve inserted into each of the several drill guide holes. Trial equipment.

(11) A patella drill guide and a trial instrument,
A posterior trial bearing surface configured to articulate with the condylar surface of an artificial femoral component, the posterior trial bearing surface comprising a curved peak surface defining the posterior surface of the patella drill guide and trial instrument. Surface and
An anterior surface having a central spike and a number of peripheral spikes extending outwardly from the anterior surface, (i) an upper/lower phantom line that extends the anterior surface in the upper/lower direction Bisected, (ii) the center of the central spike is located on the upper/lower imaginary line, and (iii) the central spike is longer than the peripheral spike;
A number of drill guide holes extending from the posterior trial bearing surface to the anterior surface through the patella drill guide and trial instrument;
A patella drill guide and trial instrument comprising.
(12) The rear bearing surface is
A medial trial articulation surface configured to articulate with the medial condyle surface of the artificial femoral component;
A lateral trial articulating surface configured to articulate with a lateral condylar surface of the artificial femoral component,
A patella drill guide and trial instrument according to embodiment 11, comprising:
(13) An imaginary line bisects the front surface in the inward/outward direction,
The patella drill guide and trial instrument according to embodiment 11, wherein a center of each of the central spike and the some peripheral spikes is positioned inside the imaginary line.
(14) The number of peripheral spikes includes an upper spike and a lower spike,
The center of the upper spike is positioned above the upper/lower imaginary line,
The patella drill guide and trial instrument according to embodiment 11, wherein the center of the lower spike is positioned below the upper/lower imaginary line.
(15) An inner/outer imaginary line bisects the front surface in the inner/outer direction,
The patella drill guide and trial instrument according to embodiment 11, wherein the centers of the central spike, the superior spike and the inferior spike are positioned inside the medial/lateral imaginary line.

(16) The patella drill guide and trial instrument according to embodiment 11, wherein the some drill guide holes are counterbore holes.
(17) further comprising a connection slot positioned between the posterior trial bearing surface and the anterior surface, the connecting slot securing the patella drill guide and trial instrument to a removable fastener. The patella drill guide and trial instrument of embodiment 11, configured to receive the connecting tongue of the removable fastener.
(18) The patella drill guide and trial instrument according to embodiment 11, wherein the posterior trial bearing surface and the anterior surface constitute a monolithic body.
(19) The patella drill guide of embodiment 11 wherein the posterior trial bearing surface and the anterior surface comprise a monolithic polymer body and further comprise a metal sleeve inserted into each of the several drill guide holes. Trial equipment.

Claims (8)

A patella drill guide and trial instrument,
(I) a posterior trial bearing surface configured to articulate with the condylar surface of the artificial femoral component, the posterior trial bearing surface comprising a curved peak surface defining the posterior surface of the patella drill guide and trial instrument. Trial bearing surface,
(Ii) a front surface positioned opposite the rear trial bearing surface,
(Iii) a plurality of peripheral spikes extending outwardly from the anterior surface, the patella drill guide and trial when the anterior surface is engaged with a surgically prepared posterior surface of a patient's patella. A plurality of peripheral spikes configured to engage a surgically-prepared posterior surface of the patient's patella to prevent the instrument from rotating relative to the patient's patella.
(Iv) a central spike extending outwardly from the anterior surface configured to engage a surgically prepared posterior surface of the patient's patella, the central spike defining a central axis. ,
(V) a number of drill guide holes extending from the posterior trial bearing surface to the anterior surface through the patella drill guide and trial instrument;
Equipped with
The patella drill guide and trial instrument has only the central spike surgically prepared of the patient's patella to allow rotational positioning of the patella drill guide and trial instrument about the central axis relative to the patient's patella. Configured to be positioned in a first position for engaging a posterior surface,
The patella drill guide and trial instrument has a second position for engaging the surgically prepared posterior surface of the patient's patella to prevent the patella drill guide and trial instrument from rotating relative to the patient's patella. A patella drill guide and trial instrument configured to position the plurality of peripheral spikes on the patella. The posterior trial bearing surface is configured to articulate with a medial trial articulating surface configured to articulate with a medial condyle surface of the artificial femoral component and with a lateral condylar surface of the artificial femoral component. A patella drill guide and trial instrument according to claim 1 including a lateral trial articulation surface that is configured. An inner/outer imaginary line bisects the front surface inward/outward,
The patella drill guide and trial instrument of claim 1, wherein a center of each of the plurality of peripheral spikes is positioned inside the medial/lateral imaginary line. The plurality of peripheral spikes include an upper spike and a lower spike, an upper/lower imaginary line bisects the front surface in an upper/lower direction, and a center of the central spike is on the upper/lower imaginary line. The patella drill guide of claim 1 and wherein the center of the upper spike is positioned above the upper / lower imaginary line and the center of the lower spike is positioned below the upper / lower imaginary line. Trial equipment. An inner/outer imaginary line bisects the front surface inward/outward,
The patella drill guide and trial instrument of claim 4, wherein the centers of each of the central spike, the upper spike, and the lower spike are positioned inside the medial/lateral imaginary line. The patella drill guide and trial instrument of claim 1, wherein the number of drill guide holes are counterbore holes. Further comprising a connection slot positioned between the posterior trial bearing surface and the anterior surface, the connection slot being removable to secure the patella drill guide and trial instrument to a removable fastener. The patella drill guide and trial instrument of claim 1, configured to receive a connecting tongue of a fastener. The patella drill guide and trial instrument of claim 1, wherein the posterior trial bearing surface, the anterior surface, and the plurality of peripheral spikes and the central spike are contained in a single monolithic body.

Images