Orthopedic prosthetic system for rotating articulated knee joint prostheses

Abstract

This invention is entitled "Orthopedic Prosthetic System for Rotationally Articulated Knee Prostheses". The invention discloses an orthopedic prosthesis comprising a femoral component configured to attach to the distal end of a patient's femur. A tibial support is configured to attach to the proximal end of a patient's tibia. A tibial insert is configured to rotate relative to the tibial support. A modular insert is received in a cavity defined within the tibial insert. The femoral component is rotatably coupled to the body of the modular insert.

Description

Technical Field

[0001] This disclosure relates generally to orthopedic prosthetic systems, including prosthetic components and methods for assembling prosthetic components during orthopedic joint replacement surgery, and more specifically to orthopedic prosthetic components and methods for assembling prosthetic components during knee replacement surgery. Background Technology

[0002] Movement of the natural human knee (e.g., flexion and extension) involves the movement of the femur and tibia. Specifically, during flexion and extension, the distal ends of the femur and the proximal ends of the tibia move relative to each other through a series of complex movements. Injuries (e.g., trauma) or diseases can damage the bone, articular cartilage, and ligaments of the knee, which can ultimately affect the natural knee's ability to function in the manner described above. Therefore, knee prostheses have been developed and implanted in the surgically prepared ends of the femur and tibia.

[0003] For example, a typical knee prosthesis for total knee replacement includes a tibial component or tibial support attached to the patient's tibia, a femoral component attached to the patient's femur, and a tibial insert positioned between the tibial support and the femoral component, including a surface for receiving the condyle of the femoral component. One type of knee prosthesis is an articulated knee prosthesis, which typically includes a hinge mechanism to connect the femoral component to one or both of the support component and the tibial component, thereby restraining and mechanically connecting the components of the knee prosthesis together. Summary of the Invention

[0004] According to one aspect of this disclosure, an orthopedic prosthesis includes a femoral component configured to attach to the distal end of a patient's femur. A tibial support is configured to attach to the proximal end of a patient's tibia. The tibial support includes a base having an outer surface, a column extending distally from the base, and a hole defined in the column and extending from the base. A tibial insert is configured to rotate relative to the tibial support. The tibial insert includes a platform shaped to engage the base of the tibial support. A rod extends distally from the platform and is received in the hole of the tibial support. A cavity extends longitudinally through the platform. A protrusion is coupled to the platform. The protrusion is configured to engage the outer surface of the base to restrict rotation of the tibial insert relative to the tibial support. A modular insert is received in a cavity defined in the tibial insert. The modular insert includes an elongated rod and a body rotatably coupled to the elongated rod. The femoral component is rotatably coupled to the body of the modular insert. The femoral component is configured to rotate about a first axis relative to the tibial insert within a first range of motion. The first axis extends in the inward and outward directions. The main body of the modular insert is configured to rotate relative to the tibia insert about a second axis extending parallel to the first axis within a second range of motion. The second range of motion is smaller than the first range of motion.

[0005] In some implementations, the body of the modular insert may be configured to rotate relative to the femoral component to move the first axis relative to the second axis within a second range of motion.

[0006] In some embodiments, an elongated pin connects the femoral component to the body of the modular insert. The elongated pin may define a first axis and may be movable relative to the tibial insert within a second range of motion between a first position and a second position. The second position may be located anterior to the first position. The modular insert may be configured to move relative to the tibial insert in a vertical direction between a lower position and an upper position within the second range of motion. When the modular insert is positioned in the lower position, the elongated pin may be in the first position. When the modular insert is positioned in the upper position, the elongated pin may be in the second position. The tibial insert may have an inner wall defining a cavity. The inner wall may have a tapered proximal surface defining a proximal segment of the cavity. When the modular insert is positioned in the lower position, the body of the modular insert may be seated within the proximal cavity segment. The inner wall of the tibial insert may have a lower basal surface. The tapered proximal surface of the tibial insert may extend from an elongated opening defined in a platform to the lower basal surface.

[0007] In some embodiments, the elongated opening may have a substantially elliptical shape. The opening may be defined in the lower basal surface. The inner wall of the tibial insert may have a distal surface defining a distal segment of the cavity. The elongated rod of the modular insert may extend into the distal cavity segment. The elongated rod of the modular insert may define a longitudinal axis. When the modular insert is positioned in the superior position, the modular insert may be allowed to rotate about the longitudinal axis relative to the tibial insert.

[0008] In some implementations, the protrusion is removably attached to the platform of the tibial insert.

[0009] In some implementations, the first range of motion can be in the range of -3 to 140 degrees of flexion. The second range of motion can be in the range of 3 to 10 degrees of flexion.

[0010] According to another aspect of this disclosure, an orthopedic prosthesis system includes a first implantable prosthesis component configured to attach to the distal end of a patient's femur. The first implantable prosthesis component includes a first body having a pair of spaced-apart curved convex condylar surfaces. A second body is rotatably coupled to the first body. An elongated rod is rotatably coupled to the second body. The second implantable prosthesis component is configured to attach to the proximal end of a patient's femur. A plug-in prosthesis component is configured to be positioned between the first and second implantable prosthesis components. The plug-in prosthesis component includes a cavity sized to receive the elongated rod of the first implantable prosthesis component. The first body is configured to rotate relative to the plug-in prosthesis component about a first axis within a first range of motion. The first axis extends in an inward-outward direction. The second body is configured to rotate relative to the plug-in prosthesis component about a second axis extending parallel to the first axis within a second range of motion. The second range of motion is smaller than the first range of motion.

[0011] In some embodiments, an elongated pin connects the first body to the second body. The elongated pin defines a first axis and is movable relative to the implantable prosthesis component between a first position and a second position within a second range of motion. The second position may be located anterior to the first position. The second body of the first implantable prosthesis component may be configured to move relative to the implantable prosthesis component in a vertical direction between a lower position and an upper position within the second range of motion. When the second body is positioned in the lower position, the elongated pin may be in the first position. When the second body is positioned in the upper position, the elongated pin may be in the second position. The implantable prosthesis component may have a pair of curved proximal surfaces. The pair of spaced-apart curved convex condylar surfaces of the second body may be configured to engage the curved proximal surfaces. The curved convex condylar surfaces and the curved proximal surfaces may be shaped such that engagement of the curved convex condylar surfaces and the curved proximal surfaces within the second range of motion causes the second body of the first implantable prosthesis component to move between the lower position and the upper position.

[0012] In some implementations, the second range of motion may overlap with the first range of motion. The first range of motion may be in the range of -3 to 140 degrees of flexion. The second range of motion may be in the range of 3 to 10 degrees of flexion.

[0013] According to another aspect of this disclosure, a plastic surgery prosthesis system includes a first implantable prosthesis component configured to attach to the distal end of a patient's femur and including a pair of spaced-apart curved convex condylar surfaces. A second implantable prosthesis component is configured to attach to the proximal end of the patient's femur. A plug-in prosthesis component is positioned between the first and second implantable prosthesis components. The plug-in prosthesis component includes a pair of curved proximal surfaces that engage with the pair of spaced-apart curved convex condylar surfaces. An elongated pin extends along a first axis. The elongated pin rotatably connects the plug-in prosthesis component to the first implantable prosthesis component. The first implantable prosthesis component is configured to rotate relative to the plug-in prosthesis component about the first axis within a range of motion. The first axis extends in an inward-outward direction. The curved convex condylar surfaces and the curved proximal surfaces are shaped such that engagement of the curved convex condylar surfaces and the curved proximal surfaces within the range of motion causes the elongated pin to move between a first position and a second position. The second position is located in front of the first position. Attached Figure Description

[0014] The specific implementation method refers to the following figures, in which:

[0015] Figure 1 An exploded view of an orthopedic knee prosthesis system;

[0016] Figure 2 for Figure 1 Top perspective view of the tibia insert and the rear insert connected to the tibia insert shown;

[0017] Figure 3 for Figure 2 The bottom perspective view of the tibia insert shown;

[0018] Figure 4 for Figure 2 The top plan view of the tibia insert shown, with the posterior insert removed;

[0019] Figure 5 for Figure 4 Rear perspective view of the tibia insert shown;

[0020] Figure 6 for Figure 2 The rear perspective of the rear plug-in shown;

[0021] Figure 7 for Figure 1 The tibia support shown Figure 1 The bottom plan view of the tibial insert connected to the tibial support is shown;

[0022] Figure 8 for Figure 1 An exploded view of the modular plugin shown;

[0023] Figure 9 for Figure 1 The bottom perspective view of the main body of the modular plug-in shown;

[0024] Figure 10 for Figure 1 Side perspective view of the modular plug-in shown;

[0025] Figure 11 for Figure 1 The side perspective view of the orthopedic knee prosthesis shown;

[0026] Figure 12 For along Figure 11 The sectional view of the orthopedic knee prosthesis system in the extended position, taken by line 12-12 shown.

[0027] Figure 13 For similar Figure 12 The image shows a view of an orthopedic knee prosthesis system in a flexed position.

[0028] Figure 14 For along Figure 12 The sectional view of the orthopedic knee prosthesis system in the extended position, taken by line 14-14 shown.

[0029] Figure 15 For along Figure 13 The cross-sectional view of an orthopedic knee prosthesis system in a flexed position, shown by line 15-15.

[0030] Figure 16 for Figure 1 The top plan view of the modular insert and tibia insert shown is illustrated, with the modular insert in a rotated position; and

[0031] Figure 17 for Figure 1 The diagram shows the top plan view of the tibia insert and tibia support, with the tibia insert in a rotated position. Detailed Implementation

[0032] While the concepts of this disclosure are readily available in various modifications and alternatives, specific exemplary embodiments thereof have been shown by way of example in the accompanying drawings and will be described in detail herein. However, it should be understood that the concepts of this disclosure are not intended to be limited to the specific forms disclosed, but rather are intended to cover all modifications, equivalents, and alternatives within the spirit and scope of the invention as defined by the appended claims.

[0033] Throughout this specification, when referring to orthopedic implants and orthopedic instruments described herein, as well as the natural anatomy of a patient, terms indicating anatomical reference, such as anterior, posterior, medial, lateral, superior, inferior, etc., may be used. These terms have well-known meanings in anatomical studies and orthopedic surgery. Unless otherwise stated, these anatomical reference terms used in the written details and claims are intended to be consistent with their well-known meanings.

[0034] See now Figure 1 An orthopedic knee prosthesis system 10 is shown. The orthopedic knee prosthesis system 10 includes: a femoral component 12 configured to attach to the distal end of a patient's femur; a tibial support 16 configured to attach to the proximal end of a patient's femur; and a tibial insert 18 configured to be assembled separately from the tibial support 16. The femoral component 12, tibial support 16, tibial insert 18, and modular insert 22 can be individually assembled to form an orthopedic knee prosthesis; specifically, an articulated orthopedic knee prosthesis, as described below.

[0035] The orthopedic knee prosthesis system 10 is configured to allow joint movement across three ranges of motion. The orthopedic knee prosthesis system 10 is capable of movement at various degrees of flexion between full extension and full flexion. As the orthopedic knee prosthesis system 10 moves across the range of flexion, the contact point between the condyle of the femoral component 12 and the condylar surface of the tibial insert 18 moves, such that the contact point is different at different degrees of flexion. Additionally, the surgeon may selectively add rotation about the superior-inferior axis. Rotation may occur between the femoral component 12 and the tibial insert 18. Rotation may also occur between the tibial insert 18 and the tibial support 16. When the system moves within the first range of flexion, the contact point between the condyles moves in the anteroposterior direction. During the second range of flexion, which is within the first range of flexion, the femoral component 12 may be allowed to rotate relative to the tibial insert 18. In some embodiments, the surgeon may also selectively allow the tibial insert 18 to rotate relative to the tibial support 16 throughout the entire first range of flexion. The amount of rotation of the tibial insert 18 relative to the tibial support 16 can be adjusted by the surgeon.

[0036] In an exemplary embodiment, the femoral component 12 includes a post 24 configured to be implanted in the distal end of a patient's femur. The post 24 is attached to a body 26 having a pair of spaced-apart lateral and medial condyles 28. Each condyle 28 includes corresponding lateral and medial condylar surfaces 30, 32, which are convexly curved. An intercondylar fossa 34 is defined between the lateral and medial condyles 28 and is sized to receive a modular insert 22. The femoral component 12 also includes a posterior bore 40 extending medially through the lateral and medial condyles 28. As described in more detail below, the bore 40 forms part of a hinge mechanism and is sized to receive a hinge pin 42.

[0037] The femoral component 12 and the tibial support 16 are each made of implantable metallic material, such as cobalt-chromium. Figure 1 As shown, the tibial support 16 includes a base 50 and an anchor 52 extending downward from the distal surface 54 of the base 50. The size and shape of the base 50 are configured to conform to the configuration of the proximal surface of the surgically prepared tibia of the patient, and the size and shape of the anchor 52 are configured to be implanted into the surgically prepared medullary canal of the patient's tibia.

[0038] The base 50 includes a generally flat proximal surface 60 positioned opposite the distal surface 54. A curved outer wall 62 extends between the distal surface 54 and the proximal surface 60, and its size and shape are configured to conform to the outer edge of the surgically prepared proximal surface of the patient's tibia. A concave posterior channel 66 is formed by the outer wall 62. An opening 64 is defined in the proximal surface 60, and the tibial support 16 includes a hole 70 extending inwardly from the opening 64. The hole 70 extends through the base 50 and into the anchor 52.

[0039] Tibial support 16 can be used with Figure 1 The tibial insert 18 shown is assembled to form a tibial component. The insert is formed from an implantable plastic material, such as ultra-high molecular weight polyethylene (UHMWPE). The tibial insert 18 includes a platform 72 and an elongated rod 74, the platform being sized to be positioned on the proximal surface 60 of the tibial support 16, the elongated rod extending downward from the distal surface 76 of the platform 72 along a longitudinal axis 78 extending in the vertical direction. Similar to the proximal surface 60 of the tibial support 16, the distal surface 76 of the platform is substantially flat. The platform 72 also includes a pair of concave, curved proximal surfaces 80, 82 corresponding to the lateral and medial condylar surfaces 30, 32 of the femoral component 12. The platform 72 also includes a curved outer wall 84 extending between the proximal surfaces 80, 82.

[0040] See now Figure 2 An opening 90 is defined in the proximal surfaces 80, 82 of the platform 72. The tibial insert 18 includes a hole 92 that extends inwardly from the opening 90 through the platform 72 and into the elongated rod 74. The hole 92 then extends along the longitudinal axis 78 of the elongated rod 74.

[0041] When attached to the tibial support 16, the distal surface 76 of the tibial insert 18 engages with the proximal surface 60 of the tibial support. The elongated rod 74 of the tibial insert 18 is sized to be received in the hole 70 of the tibial support 16 when the tibial insert 18 is attached to the tibial support.

[0042] See again Figure 1 Modular insert 22 includes an elongated rod 100 extending along longitudinal axis 78 (shown in...). Figure 8(Middle). The proximal body 104 is pivotally attached to the elongated rod 100. The elongated rod 100 is sized and shaped to insert into the opening 90 and extend into the hole 92 of the tibial insert 18. The proximal body 104 includes an inner opening 106, an outer opening 108, and an inner wall 110 extending between the inner opening 106 and the outer opening 108. The inner wall 110 defines a cylindrical pin hole 112 extending through the proximal body 104.

[0043] The proximal body 104 of the modular insert is sized and shaped to be positioned within the intercondylar fossa 34 of the femoral component 12, such that the posterior bore 40 can be aligned with the channel 116 of the modular insert 22. A hinge pin 42 extends along a longitudinal axis 20 extending in the medial-lateral direction through the posterior bore 40 and the channel 116 to attach the modular insert 22 to the femoral component 12. As described above, the tibial support 16 and the tibial insert 18 can be combined with the femoral component 12 and the modular insert 22 to form an articulated orthopedic knee prosthesis.

[0044] See Figure 2 and 3 The posterior component 130 is removably coupled to the posterior side 132 of the platform 72 of the tibial insert using fasteners 136. The posterior component 130 limits the amount of rotation between the tibial insert 18 and the tibial support 16. In some embodiments, multiple posterior components 130 may be provided, each providing a different predetermined amount of rotation between the tibial insert 18 and the tibial support 16. In some embodiments, the posterior component 130 may be provided to completely restrict rotation between the tibial insert 18 and the tibial support 16. The posterior component 130 includes a downwardly extending protrusion 134 extending from a surface of the posterior component 130. When the posterior component 130 is coupled to the tibial insert 18, the protrusion 134 extends from the distal surface 76 of the tibial insert 18. In some cases, the posterior component 130 is integrally formed with the tibial insert 18. The protrusion 134 extends a length 138 from the distal surface 76. The protrusion 134 includes a flat sidewall 140 extending along the posterior surface 132 of the tibial insert 18. A curved sidewall 142 extends anteriorly and superiorly from the flat sidewall 140. The curved sidewall 142 extends below the distal surface 76 of the tibial insert 18.

[0045] The curved sidewall 142 is sized to be positioned within the channel 66 of the tibial support 16. The curved sidewall 142 is sized smaller than the channel 66, allowing the tibial insert 18 to rotate relative to the tibial support 16, as described in more detail below. In other embodiments, the protrusions 134 of different posterior components 130 include curved sidewalls 144 (shown in dashed lines) sized to be fixed within the channel 66 to prevent rotation of the tibial insert 18 relative to the tibial support 16, as described in more detail below. As described above, the orthopedic knee prosthesis system 10 may include multiple posterior components 130 having protrusions 134 sized differently. Therefore, the surgeon can select the protrusion size based on a preferred amount of rotation. In some embodiments, the tibial support 16 rotates in 5-degree increments within a range of 0 to + / -20 degrees.

[0046] like Figure 4 and Figure 5 As shown, the tibial insert 18 includes a mounting cavity 168 extending from a superior opening 170 formed in proximal surfaces 80, 82 and an opening 172 formed in a posterior surface 132. The mounting cavity 168 is sized to receive the posterior component 130 when it is attached to the tibial insert 18. A bore 174 extends from the superior opening 170 and the opening 172, and is sized to receive the posterior component 130. The bore 174 includes a pair of posterior planar sidewalls 176 extending from the superior opening 170 to the bottom wall 178. A curved end wall 180 extends from the bottom wall 178 to the distal surface 76 of the tibial insert 18. A pair of openings 182 are formed in the curved end wall 180. The bore 184 extends from each opening 182 into the tibial insert 18. The curved notch 186 extends medially and laterally from the curved end wall 180 along the posterior surface 132 of the tibial insert 18.

[0047] See now Figure 6 The rear component 130 includes a body 196. A protrusion 134 extends downward from the body 196. A pair of upper flanges 198 extend forward and upward from the body 196. The upper flanges 198 are sized and shaped to be received in a proximal cavity 154 of the tibial insert 18. A pair of lower flanges 200 extend medially and laterally from the body 196. Each of the pair of lower flanges 200 is sized and shaped to be positioned in a corresponding curved notch 186 of the tibial insert 18.

[0048] A pair of openings 202 are formed in the rear end 204 of the body 196. Boring holes 188 extend inwardly from each of the pair of openings 202 through the body 196 of the rear member 130. Boring holes 188 are configured to align with boring holes 174 of the tibial insert 18 when the rear member 130 is engaged with the tibial insert 18. Fasteners 136 are received in boring holes 174 and 188 to secure the rear member 130 to the tibial insert 18. In some embodiments, boring holes 188 and 174 are threaded to receive threaded fasteners 136.

[0049] Figure 7 A protrusion 134 of the posterior member 130 extending into the channel 66 of the tibial support 16 is shown when the tibial insert 18 is attached to the tibial support 16. The channel 66 of the tibial support 16 includes a curved sidewall 206 extending from an opening 208 having a length of 210. The protrusion 134 is dimensioned such that the length of the flat sidewall 140 is less than the length 210 of the opening 208. Additionally, the curved sidewall 142 of the protrusion 134 is dimensioned smaller than the curved sidewall 206 of the channel 66 to allow movement of the protrusion 134 within the channel 66. The combination of the dimensions of the flat sidewall 140 and the curved sidewall 142 relative to the dimensions of the channel 66 allows for restricted rotation of the tibial insert 18 relative to the tibial support 16. That is, the tibial insert 18 is allowed to rotate about a longitudinal axis 78 until the curved sidewall 142 of the protrusion 134 contacts the curved sidewall 206 of the channel 66.

[0050] In another embodiment, the protrusion 134 includes a curved sidewall 144. In such an embodiment, the flat sidewall 140 has a length 212 that is substantially equal to the length 210 of the opening 208. Additionally, the curved sidewall 144 of the protrusion 134 is sized to contact the curved sidewall 206 of the channel 66 to prevent rotation of the tibial insert 18 relative to the tibial support 16.

[0051] See again Figure 4The orifice 92 of the tibial insert 18 includes a tapering inner wall 150 extending from the platform 72 to the lower bottom wall 152 to define a proximal cavity 154 extending longitudinally through the platform 72. The inner wall 150 slopes radially inward from the platform 72 to the lower bottom wall 152. The inner wall 150 is substantially elliptical in shape, such that the proximal cavity 154 includes a long axis 156 extending in the anteroposterior direction and a short axis 158 extending in the medial-lateral direction. The length 160 of the long axis 156 is greater than the length 162 of the short axis 158. In some embodiments, the short axis 158 extends in the anteroposterior direction, and the long axis 156 extends in the medial-lateral direction. At the platform 72, the long axis 156 and the short axis 158 each have their maximum length. Due to the slope of the inner wall 150, the long axis 156 and the short axis 158 have their minimum length at the lower bottom wall 152. The lengths of the major axis 156 and the minor axis 158 gradually decrease between the platform 72 and the lower bottom wall 152, thus experiencing various intermediate lengths.

[0052] An opening 164 is formed in the lower bottom wall 152. A distal cavity 166 extends from the opening 164. The distal cavity 166 is generally cylindrical in shape and extends from the opening 164 to the bottom wall 178. The distal cavity 166 is sized to receive an elongated rod 100 of the modular insert 22.

[0053] See now Figure 8 An elongated rod 100 of the modular insert 22 extends between a distal end 220 and a proximal end 222. The distal end 220 of the elongated rod 100 is sized to be positioned within the distal cavity 166 of the tibial insert 18. The proximal end 222 includes a circular outer wall 226 and a pair of linear sidewalls 228 extending from the circular outer wall 226. A pin hole 230 extends between a pair of openings 232 formed in the proximal end 222. Each of a pair of bushings 240 is sized to be positioned within one of the openings 232.

[0054] Each bushing 240 includes a body 242 and a flange 244 extending around the body 242. The diameter 246 of the flange 244 is larger than the diameter 248 of the body 242. The diameter 248 of the body 242 is sized such that the body 242 is positioned within the opening 232. The diameter 246 of the flange 244 is sized such that the flange 244 is positioned against a corresponding sidewall 228.

[0055] Each bushing 240 includes a pin hole 250 extending between a pair of openings 252. The pin hole 250 is sized to receive a pin 254 along a longitudinal axis 256 that extends in an inward or outward direction parallel to the longitudinal axis 20. The pin 254 includes a cylindrical shaft 258, the diameter 260 of which is sized to match the diameter 270 of the pin hole 250. A threaded head 272 extends from the shaft 258. The diameter 274 of the threaded head 272 is larger than the diameter 260 of the shaft 258.

[0056] The proximal body 104 of the modular insert 22 includes a distal segment 280 and a ridge 282 extending proximally from the distal segment 280. Fasteners 284 are configured to secure the ridge 282 to the distal segment 280. The distal segment 280 is sized to be positioned within the proximal cavity 154 of the tibial insert 18. The distal segment 280 includes a lateral wall 286 whose dimensions and shape are configured to conform to the inner wall 150 of the tibial insert 18. The lateral wall 286 is generally elliptical in shape and slopes from a superior end 288 to a inferior end 298. The distal segment 280 is configured to receive the proximal end 222 of the elongated rod 100.

[0057] See now Figure 9 The outer wall 286 includes a long axis 290 extending in a retardation direction and a short axis 292 extending in a medial-lateral direction. The length 294 of the long axis 290 is greater than the length 296 of the short axis 292. In some embodiments, the long axis 290 extends in the medial-lateral direction, and the short axis 292 extends in the retardation direction. The distal segment 280 includes a cavity 300 extending from an opening 302 in the distal end 304 of the distal segment 280. The cavity 300 is sized and shaped to receive the proximal end 222 of the elongated rod 100.

[0058] At the upper end 288, the major axis 290 and the minor axis 292 each have their maximum length. Due to the inclination of the outer side wall 286, the major axis 290 and the minor axis 292 have their minimum length at the lower end 298. The lengths of the major axis 290 and the minor axis 292 gradually decrease between the upper end 288 and the lower end 298, thus experiencing various intermediate lengths.

[0059] The lateral wall 286 is configured to engage the inner wall 150 of the tibial insert 18 when the modular insert 22 is attached to the tibial insert 18. In the initial extended position, the distal segment 280 of the modular insert 22 is seated in the bore 92 of the tibial insert 18, with the distal end 298 positioned against the lower bottom wall 152 of the tibial insert 18. The lateral wall 286 is positioned against the inner wall 150 of the tibial insert 18. During flexion of the femoral component 12 relative to the tibial insert 18, the modular insert 22 moves upward, causing the distal end 298 to separate from the lower bottom wall 152 of the tibial insert 18. In the separated position, the long axis 290 and short axis 292 of the modular insert 22 are positioned such that at any given location, the lengths of the long axis 290 and short axis 292 are both less than the lengths of the aligned long axis 156 and short axis 158. For example, the long axis 156 and short axis 158 at platform 72 are aligned with the shorter intermediate long axis 290 and short axis 292 of modular plug 22, thereby allowing the modular plug 22 to rotate relative to the tibia plug 18.

[0060] See again Figure 8 The threaded bore 310 extends from the opening 280 in the distal section 312 and enters the cavity 300. For example... Figure 10 As shown, when the proximal end 222 of the elongated rod 100 is received in the cavity 300, the threaded bore 310 is configured to align with the pin hole 230 of the elongated rod 100 and the pin hole 250 of the bushing 240 to define a channel 320. The channel 320 is configured to receive a pin 254 to hingedly attach the distal segment 280 to the elongated rod 100. A threaded head 272 is secured to the thread 322 of the bore 310 to secure the pin 254 to the distal segment 280. The proximal body 104 of the modular insert 22 is configured to rotate relative to the elongated rod 100 about a longitudinal axis 256 in the direction of arrow 324.

[0061] The ridge 282 of the proximal body 104 includes a channel 116 extending between an inner opening 106 and an outer opening 108. The size and shape of each opening 106, 108 are configured to receive a bushing 334. Each bushing 334 includes a bore 336 extending between openings 338. Figure 11 As shown, bore 336 is configured to align with rear bore 40 of femoral component 12 when femoral component 12 is attached to modular insert 22. Hinge pin 42 extends through rear bore 40, channel 116, and bore 336 to pivotally attach modular insert 22 to femoral component 12 along longitudinal axis 20. Femoral component 12 is configured to rotate about arrow 340 when attached to modular insert 22.

[0062] During a knee replacement surgery, the surgeon selects the femoral component 12 and the tibial support 16. The ends of the patient's femur and tibia are removed to prepare for insertion into the orthopedic knee prosthesis system 10. The surgeon drills medullary cavities in the femur and tibia to receive the column 24 of the femoral component 12 and the elongated rod 74 of the tibial support 16, respectively. Generally, the orthopedic knee prosthesis system 10 includes various femoral components 12 and tibial supports 16 of different sizes. The surgeon selects the femoral component 12 and the tibial support 16 based on the anatomy of the patient's knee joint. The femoral component 12 is attached to the end of the femur by inserting the column 24 into the medullary cavity of the femur. Similarly, the tibial support 16 is attached to the tibia by inserting the elongated rod 74 into the medullary cavity of the tibia.

[0063] The surgeon then selects a tibial insert 18 from a plurality of tibial inserts 18 of different sizes. Each tibial insert 18 may have condylar surfaces 30, 32 set to different sizes and shapes. The surgeon tests the range of motion of the orthopedic knee prosthesis system 10 by moving the femoral component 12 through a first range of motion between a fully extended position and a fully flexed position. During flexion of the orthopedic knee prosthesis system 10, the surgeon evaluates the movement of the femoral component 12 along the tibial insert 18. The surgeon may select to test multiple tibial inserts 18 until the desired range of motion is achieved.

[0064] As described below, the tibial insert 18 can also be selected based on the dimensions of the proximal cavity 154 of the tibial insert 18. The dimensions of the proximal cavity 154 are varied to allow rotation between the modular insert 22 and the tibial insert 18.

[0065] A posterior component 130 is selected from a plurality of posterior components 130 for attachment to a tibial insert 18. Each of the posterior components 130 includes a protrusion 134 having a flat sidewall 140 and a curved sidewall 142 configured to different sizes. In some embodiments, the posterior component 130 is integrally formed with the tibial insert 18, and each tibial insert 18 has a protrusion 134 configured to different sizes. With the posterior component 130 attached to the tibial insert 18, the surgeon tests the range of rotation of the tibial insert 18 relative to the tibial support 16. The surgeon selects the posterior component 130 based on the desired range of rotation. In some embodiments, the surgeon may select a posterior component 130 that prevents rotation of the tibial insert 18 relative to the tibial support 16.

[0066] Modular inserts 22 are selected from multiple modular inserts 22 of different sizes. The dimensions of the modular inserts 22 are chosen such that when the system is fully extended, the distal segment 280 of the modular insert 22 is positioned in a seated position within the proximal cavity 154. The surgeon retests the orthopedic knee prosthesis system 10 by flexing the femoral component 12 through a first range of motion. In intermediate flexion, the femoral component 12 enters a second range of flexion located within the first range of flexion. The second range of flexion lies between intermediate flexion and full extension. In intermediate flexion, the distal segment 280 of the modular insert 22 becomes disseminated within the proximal cavity 154.

[0067] Through the second flexion range, the distal segment 280 is pulled upward within the proximal cavity 154, allowing the modular insert 22 to rotate relative to the tibial insert 18. The surgeon tests the range of rotation of the modular insert 22 and selects the modular insert 22 that provides the desired range of flexion. In some embodiments, the surgeon may select to use different tibial inserts 18 with proximal cavities 154 set to different sizes to achieve the desired range of rotation. The surgeon may also select the modular insert 22 and the tibial insert 18 based on the range of motion and the second flexion range.

[0068] Therefore, during surgery, the surgeon tests multiple ranges of motion to select the desired component. The surgeon evaluates a first range of motion from full extension to full flexion, and a second range of motion from intermediate flexion to full flexion. Additionally, the surgeon evaluates a first range of rotation of the tibial insert 18 relative to the tibial support 16, and a second range of rotation of the modular insert 22 relative to the tibial insert 18. It should be noted that the second range of rotation may fall within the first range of rotation.

[0069] See now Figure 12 In the fully extended position 400, the elongated rod 100 extends into the inferior position 398 within the distal cavity 166 of the tibial insert 18, such that the distal end 402 of the distal end 220 is positioned adjacent to the bottom 404 of the distal cavity 166. The elongated rod 100 extends along the longitudinal axis 78. The distal segment 280 of the proximal body 104 of the modular insert 22 is seated within the cavity 300. The hinge pin 42 is located in the fully extended position 416. Figure 14 As shown, the lateral wall 286 of the distal segment 280 is positioned against the inner wall 150 of the tibial insert 18. The lateral wall 286 of the distal segment 280 contacts the inner wall 150 of the tibial insert 18 to prevent the modular insert 22 from rotating inward or outward relative to the tibial insert 18 and to hold the modular insert 22 in a fixed position 412.

[0070] See Figure 13In the fully flexed position 420, the femoral component 12 rotates about the longitudinal axis 20 over a first flexion range that includes a second flexion range, as indicated by arrow 422. In one embodiment, the first flexion range is in the range of -3 to 140 degrees. The engagement of the curved convex condylar surfaces 30, 32 with the curved proximal surfaces 80, 82 during the first flexion range causes the modular insert 22 to move upward from the inferior position 398 to the superior position 396 within the proximal cavity 154. As the femoral component 12 rotates, the elongated rod 100 moves upward in the superior position 396 within the distal cavity 166 in the upward direction as indicated by arrow 424, such that the distal end 402 of the distal end 220 is advanced away from the bottom 404 of the distal cavity 166. The proximal body 104 of the modular insert 22 is also advanced upward, such that the distal segment 280 is raised within the cavity 300.

[0071] The proximal body 104 of the modular insert 22 then rotates relative to the elongated rod 100 about the longitudinal axis 256 in a second range of motion from intermediate flexion to full extension, as indicated by arrow 430. In some embodiments, the second flexion range is between 3 and 10 degrees. The second range of motion overlaps with the first range of motion. During the second flexion range of the femoral component 12, the longitudinal axis 20 moves relative to the longitudinal axis 256 in the second range of motion. As the longitudinal axis 20 moves relative to the longitudinal axis 256, the hinge pin 42 moves between a fully flexed position 416 and a fully extended position 418. The second position 418 is located anterior to the first position 416.

[0072] like Figure 15 As shown, during the second flexion range, the lateral wall 286 of the distal segment 280 separates from the medial wall 150 of the tibial insert 18, thereby allowing the modular insert 22 to rotate laterally or laterally relative to the tibial insert 18. An example of the modular insert 22 rotating about the longitudinal axis 78 to a rotational position 432 is provided. Figure 16 middle.

[0073] When the femoral component 12 returns to the extended position 400, the modular insert 22 is advanced distally into the distal cavity 166, so that the lateral wall 286 of the distal segment 280 engages the inner wall 150 of the tibial insert 18, thereby causing the modular insert 22 to rotate back to the fixed position 412.

[0074] See now Figure 17In some embodiments, the tibial insert 18 is also capable of rotating inward and outward relative to the tibial support 16. In embodiments where the dimension of the curved sidewall 142 of the protrusion 134 is set smaller than that of the curved sidewall 206 of the channel 66, the tibial insert 18 rotates about the longitudinal axis 78 in the extended position 400 or the flexed position 420. The tibial insert 18 is allowed to rotate inward or outward to a rotation position 440, examples of which are provided in Figure 17 The range of rotation is determined by the size of the protrusion 134. A smaller protrusion 134 will provide more rotation compared to a larger protrusion 134. The tibial insert 18 is allowed to rotate around until the curved sidewall 142 of the protrusion 134 contacts the curved sidewall 206 of the channel 66.

[0075] Although the present disclosure has been illustrated and described in detail in the accompanying drawings and the foregoing description, such illustrations and descriptions should be regarded as exemplary rather than limiting in nature. It should be understood that only exemplary embodiments have been shown and described, and all changes and modifications made within the substance of the present disclosure should be protected.

[0076] The various features of the apparatus and components described herein give this disclosure several advantages. It should be noted that alternative embodiments of the apparatus and components of this disclosure may not include all of the described features, but may still benefit from at least some of the advantages of these features. Those skilled in the art can readily design their own implementations of the apparatus and components that integrate one or more of the features of the invention and fall within the spirit and scope of this disclosure as defined by the claims.

Claims

1. A plastic surgery prosthesis, comprising: A femoral component, the femoral component being configured to attach to the distal end of the patient's femur; A tibial support, configured to attach to the proximal end of a patient's tibia, the tibial support comprising (i) a base having an outer surface, (ii) a post extending distally from the base, and (iii) a hole defined extending in the post and the base. A tibial insert configured to rotate relative to the tibial support, the tibial insert including (i) a platform shaped to engage the base of the tibial support; (ii) A rod that extends distally from the platform and is received in the hole of the tibial support; (iii) A cavity that extends longitudinally through the platform; and (iv) a protrusion coupled to the platform, the protrusion being configured to engage the outer surface of the base to restrict rotation of the tibial insert relative to the tibial support, and a modular insert received within the cavity defined in the tibial insert, the modular insert comprising (i) an elongated rod and (ii) a body rotatably coupled to the elongated rod. The femoral component is rotatably coupled to the body of the modular insert, the femoral component being configured to rotate relative to the tibial insert about a first axis within a first range of motion, the first axis extending in an inward and outward direction, and The body of the modular insert is configured to rotate relative to the tibia insert about a second axis extending parallel to the first axis within a second range of motion, the second range of motion being smaller than the first range of motion.

2. The orthopedic prosthesis of claim 1, wherein the body of the modular insert is configured to rotate relative to the femoral component to move the first axis relative to the second axis within the second range of motion.

3. The orthopedic prosthesis of claim 1, further comprising an elongated pin connecting the femoral component to the body of the modular insert, wherein the elongated pin defines the first axis and is movable relative to the tibial insert between a first position and a second position within a second range of motion, the second position being anterior to the first position.

4. The plastic surgery prosthesis according to claim 3, wherein: The modular insert is configured to move relative to the tibia insert in the vertical direction between a lower and upper position within the second range of motion. When the modular insert is positioned at the lower side, the elongated pin is in the first position, and When the modular plug is positioned at the upper side, the slender pin is in the second position.

5. The plastic surgery prosthesis according to claim 4, wherein: The tibial insert includes an inner wall defining the cavity, the inner wall including a tapering proximal surface defining a proximal segment of the cavity, and When the modular plug-in is positioned at the lower side, the main body of the modular plug-in is placed in the proximal section of the cavity.

6. The orthopedic prosthesis of claim 5, wherein the inner wall of the tibial insert includes a lower base surface, and the tapered proximal surface of the tibial insert extends from an elongated opening defined in the platform to the lower base surface.

7. The orthopedic prosthesis of claim 6, wherein the elongated opening has a substantially elliptical shape.

8. The plastic surgery prosthesis according to claim 6, wherein: The opening is defined in the lower base surface. The inner wall of the tibial insert includes a distal surface that defines a distal segment of the cavity, and The elongated rod of the modular plug extends into the distal cavity section.

9. The plastic surgery prosthesis according to claim 5, wherein: The elongated rod of the modular plug defines a longitudinal axis, and When the modular insert is positioned in the upper position, the modular insert is allowed to rotate about the longitudinal axis relative to the tibia insert.

10. The orthopedic prosthesis of claim 1, wherein the protrusion is removably coupled to the platform of the tibial insert.

11. The orthopedic prosthesis of claim 1, wherein the first range of motion is in the range of -3 to 140 degrees of curvature.

12. The orthopedic prosthesis of claim 11, wherein the second range of motion is in the range of 3 to 10 degrees of curvature.

13. A plastic surgery prosthesis system, comprising: A first implantable prosthesis component, configured to be attached to the distal end of a patient’s femur, the first implantable prosthesis component including (i) a first body having a pair of spaced-apart curved convex condylar surfaces. (ii) a second body, which is rotatably connected to the first body; and (iii) an elongated rod, which is rotatably connected to the second body. A second implantable prosthetic component, configured to attach to the proximal end of the patient's tibia, and A plug-in prosthesis component configured to be positioned between a first implantable prosthesis component and a second implantable prosthesis component, the plug-in prosthesis component including a cavity sized to receive the elongated rod of the first implantable prosthesis component. The first body is configured to rotate relative to the prosthetic component about a first axis within a first range of motion, the first axis extending in an inward or outward direction, and the second body is configured to rotate relative to the prosthetic component about a second axis extending parallel to the first axis within a second range of motion, the second range of motion being smaller than the first range of motion.

14. The orthopedic prosthesis system of claim 13, further comprising an elongated pin connecting the first body to the second body, wherein the elongated pin defines the first axis and is movable relative to the insert prosthesis component between a first position and a second position within a second range of motion, the second position being located anterior to the first position.

15. The orthopedic prosthesis system according to claim 14, wherein: The second body of the first implantable prosthesis component is configured to move relative to the plug-in prosthesis component in the vertical direction between a lower position and an upper position within the second range of motion. When the second body is positioned at the lower side, the elongated pin is in the first position, and When the second body is positioned on the upper side, the elongated pin is in the second position.

16. The orthopedic prosthesis system according to claim 15, wherein: The insert prosthesis component includes a pair of curved proximal surfaces, and the pair of spaced-apart curved convex condylar surfaces of the first body are configured to engage the curved proximal surfaces. The curved convex condylar surface and the curved proximal surface are shaped such that the engagement of the curved convex condylar surface and the curved proximal surface within the second range of motion causes the second body of the first implantable prosthesis to move between the lower position and the upper position.

17. The orthopedic prosthesis system of claim 13, wherein the second range of motion overlaps with the first range of motion.

18. The orthopedic prosthesis system of claim 13, wherein the first range of motion is in the range of -3 to 140 degrees of curvature.

19. The orthopedic prosthesis system of claim 13, wherein the second range of motion is in the range of 3 to 10 degrees of curvature.

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