JPWO2021149000A5

JPWO2021149000A5 -

Info

Publication number: JPWO2021149000A5
Application number: JP2022545032A
Authority: JP
Publication date: 2023-11-21

Claims

A computer-assisted method of creating a natural, personalized implant for a patient, the method comprising the steps of:
(a) measuring the patient's preoperative condition, including at least the following items;
(i) HKA alignment
(ii) Relative movement of the femur with respect to the tibia (combination of sliding and rolling movements)
(iii) Contact surface and bone shape of femur and tibia
(iv) the shape and position of the patella relative to the femur and tibia, and the contact surface of the patella with the femur;
(b) If not an outlier, replicate post-surgical 3D HKA realignment to pre-arthritic HKA;
(c) define post-surgical 3D HKA realignment and correct any outliers to pre-arthritic HKA;
(d) in accordance with (b), (c) and (a)(ii), define the relative movement (combined sliding and rolling motion) of said femur with respect to the tibia after the subject's surgery;
(e) define the shape of the contact surfaces of the femoral and tibial prostheses according to (b), (c), and (a)(iii);
(f) defining the shape of the femoral and tibial prosthesis attachments in accordance with (e) and (a)(iii);
(g) for said femoral prosthesis and for said tibial prosthesis according to (b), (c), (d), (e), (a)(iv) and the patient's anatomical history (if known); Define the position of the patella after the target surgery,
(h) define the shape of the contact surface between the femoral prosthesis and the patella according to (b), (c), (e), (g) and (a) (iv) (said patellar component and said contact surfaces only between the femoral component and the patellar component, but not with the tibial component);
(i) perform other measurements according to the needs of the patient;
(j) creating an artificial joint according to measurements and definitions;

further measuring the preoperative anteroposterior dimensions of the distal femur and replicating the correct AP prosthesis femoral size such that the implant cannot rotate (or tilt or flex) more than 10° in the sagittal plane; 2. The method of claim 1, comprising:

Measuring the pre-operative distal posterior FMA and TMA (joint line);
Replicating the post-surgery FMA and TMA slopes to the pre-arthritis FMA and TMA slopes if they are not outliers;
replicating the arthritic anterior femoral torsion;
If there is an outlier, defining the post-surgery FMA, TMA slope to the corrected pre-arthritis FMA, TMA slope, and adapting the femoral torsion according to the planning matrix;
2. The method of claim 1, further comprising:

Measuring the pre-surgery TL inclination and trochlear depth;
defining, according to the rules disclosed in the planning matrix, which part of the final slope will be made on the bone (orientation of the resection) and which part will be integrated into the implant (condylar offset);
2. The method of claim 1, further comprising:

If it is not an outlier, replicating the post-surgery TL slope to the pre-arthritic TL slope and replicating the trochlear depth;
or defining the post-surgery TL slope to the corrected pre-arthritic TL slope if there is an outlier, and duplicating the trochlear depth by adding a lateral ridge to the trochlea;
2. The method of claim 1, further comprising any of the following.

replicating the post-operative condylar and trochlear JL curves to the pre-arthritic JL curves if they are not outliers;
By correcting the JL curve of the lateral condyle if there is an outlier or hypoplasia, or of both condyles in the case of sagittal deformity such as anti-tension or large flexion, the condylar and trochlear joint line curves after surgery can be corrected. defining a corrected pre-arthritic JL curve;
2. The method of claim 1, further comprising any of the following.

replicating the post-operative condylar and mediolateral trochlear curves to the pre-arthritic ML if not an outlier;
If there is an outlier, correct the ML curve of the lateral condyle or of both condyles in the case of sagittal deformity such as antitension or large flexion, and correct the postoperative condylar and trochlear ML curves. Steps defined in the curve,
2. The method of claim 1, further comprising any of the following.

2. The method of claim 1, further comprising measuring a distance from the axis of each condyle to the mid-knee and replicating the distance.

2. The method of claim 1, further comprising the step of defining the lateral limits (contours) of the condyle and trochlear articular surfaces to avoid extrusion or undersizing of the prosthesis.

measuring the preoperative posterior tibial slope;
if not an outlier, replicating the post-operative posterior tibial slope (TPS) to the corrected pre-arthritic TPS;
If there is an outlier, defining the post-operative posterior tibial slope to the corrected pre-arthritic TPS;
2. The method of claim 1, further comprising any of the following.

Define the rotation of the tibial component by measuring the angle relative to the anterior tibial tuberosity (TTA), i.e., the AP axis, and by an axis passing through the center of two circles that describe the mediolateral tibial surface geometry (ML axis). 2. The method of claim 1, further comprising:

2. The method of claim 1, further comprising defining AP and ML positions of the tibial keel to accurately center the keel on the metaphysis and/or shaft of the tibia.

The lateral limits of the contour of the tibial component (to the tibial edge) are adjusted to avoid protrusion (risk of collision with surrounding soft tissue and pain) or reduction (risk of subsidence and revision) of the prosthesis. 2. The method of claim 1, further comprising the step of defining.

2. The method of claim 1, further comprising measuring a distance (difference in extension) between the distal femoral resection and the proximal tibial resection to account for the global thickness of the implant. Method.

2. The prosthetic joint components, the tibial insert, the tibial tray, and the keel, each consisting of one or more parts and adapted to be assembled before or during surgery. artificial joint .

At least one of said components
(a) one element selected from one of the following element groups,
(i) Articular surface of the tibial insertion, including the medial condylar corresponding surface (1262)
(ii) Pulley compatible surface (1263)
(iii) Lateral condyle corresponding surface (1263)
(b) a bone-facing surface (1230) of the tibial tray;
(c) the keel portion (1240);
The artificial joint according to claim 15 , comprising:

17. Any desired orientation angles, offsets, and any combinations thereof are applied to the tibial insert, tibial tray, and keel to best meet the needs of the individual patient. Artificial joint .

18. A joint prosthesis according to claim 16 or 17, wherein the tibial insert, the tibial tray, and the keel are each formed of one or more elements.

19. Any one of claims 15 to 18 , wherein the keel (1240) is formed non-orthogonally to the bone-facing surface (1230) and oriented at a selected angle (1242) to meet the needs of the individual patient. Artificial joint described in.

To meet the needs of the individual patient, the keel (1240) is oriented at another angle (1242) rather than perpendicular to the bone-facing surface (1230), and the bone-facing surface (1230) is oriented at an angle (1232). ) The prosthetic joint according to any one of claims 15 to 19 .

21. The prosthesis of claim 20 , wherein the medial insertion thickness is reduced so that the knee is oriented in varus.

To meet the needs of the individual patient, the keel (1240) is oriented at a selected angle (1242) rather than perpendicular to the bone-facing surface (1230), and the bone-facing surface (1230) is oriented at another selected angle. A prosthesis according to any one of claims 15 to 19, oriented at (1232), with the lateral condyle-corresponding surface (1264) exhibiting an offset (1265).

To meet the needs of the individual patient, the keel (1240) is oriented at a selected angle (1242) rather than perpendicular to the bone-facing surface (1230), and the bone-facing surface (1230) is oriented at a second selection. A joint prosthesis according to any one of claims 15 to 22 , oriented at an angle (1232), said bicondylar distal tangent (1266) being oriented at a third selected angle (1267).

24. According to any one of claims 15 to 23, the offset (1265) is selected from the range 0 to 10 mm and the orientation angle (1232, 1242, 1267) of the offset angle is selected from the range up to 12°. Artificial joint as described.

25. The prosthesis of claim 24 , wherein the offset is selected from a range of -10° to +10° in a mediolateral or anteroposterior dimension and is oriented at an angle of up to 12° about the longitudinal axis of the keel.

Any of claims 15 to 25 , wherein the sagittal J- curve (1310) is adapted to fit a corresponding surface of the femoral prosthesis so that the function of the knee prosthesis is tailored to the needs of the individual patient. The artificial joint according to item 1.

27. The prosthesis of claim 26 , wherein the sagittal J-curve (1310) is essentially single radius.

27. Prosthesis according to claim 26 , wherein the sagittal J-curve (1310) is essentially a combination of two or more radii (1312, 1313, 1314, 1315), the dimensions of which are in the range 15 mm to 80 mm. .

In order to fit the tibia of the individual patient, the keel (1340) of the tibial component (1300) of the knee prosthesis of the invention is located in the center of the tibial component (1300) in the sagittal plane, optionally A prosthesis according to any one of claims 15 to 28, which exhibits an offset (1342) in the anterior direction of the tibia or in the posterior direction of the tibia.

A joint prosthesis according to claim 29 , wherein the offset (1342) is selected from a range of 0 to 10 mm.

31. A joint prosthesis according to claim 30 , wherein the offset is selected from a range of -10° to +10° in a mediolateral or anteroposterior dimension, and up to a range of 12° about the longitudinal axis of the keel.

For the same purpose of fitting the tibia of the individual patient, in the sagittal plane, the bone-facing surface (1332) of the tibial component (1300) of the knee prosthesis varies from 0° to 12°. 32. A prosthesis according to claim 31 , oriented at an angle (1344) selected from a range.

Articular surfaces (1862, 1863, 1864) of said patellar component are created to match corresponding surfaces (1852, 1853, 1854) of said femoral component, respectively, whether normal, varus, or valgus. 33. A joint prosthesis according to any one of claims 15 to 32, which also takes into account the patient's hip-knee-ankle (HKA) alignment.

If the femoral component has an offset (1872, 1874) between the distal lateral condyle and the distal medial condyle, the offset (1872, 1874) is replicated within the patellar component . 34. The artificial joint according to any one of 33 .

To meet the needs of the individual patient, selectively using a planning algorithm, the patellar component and medial and medial surfaces can be symmetrical or asymmetrical between the medial and medial compartments, and the anteroposterior surface can be symmetrical or asymmetrical between the anterior and posterior compartments. 35. The artificial joint of claim 34 .

The width and height of each of the medial, lateral, anterior, and posterior compartments are in the range from 8 mm to 30 mm, independent of the thickness of the patella, which thickness is at least 6 mm. The artificial joint according to any one of claims 15 to 35, selected from the range.

Curve/surface fitting and smoothing techniques are applied between interacting shapes across adjacent bone compartments to blend elements of the prosthesis that correspond to bone compartments to adapt to the patient's needs. 2. The method of claim 1 , including the step of creating a hybrid knee prosthesis .

A method for creating a partial or complete knee prosthesis adapted to the structural anatomy of an individual patient, the method comprising: hip-knee-ankle (HKA) alignment of A method in which the recreated natural knee joint model is used to create a prosthetic joint that recreates the natural knee joint.

A femoral prosthesis for implantation in the femur of a patient's knee,
(a) having a bone-facing surface comprising a medial condyle and a lateral condyle, abutting at least a portion of each condyle of the patient's knee, and an articular surface typically located opposite each bone-facing surface; Each articular surface has a curvature (J-curve) normally located in a first plane (sagittal plane) and a second and third plane (frontal plane in the case of the distal condyle, coronal plane in the case of the posterior condyle). an ML curve typically disposed in a transverse plane), each articular surface of the medial condyle and lateral condyle having a condylar offset in the second and third planes, optionally equivalent two condyles, which are;
(b) a bone-facing surface comprising said trochlear depth and said medial trochlear ridge and said lateral trochlear ridge and adjoining at least a portion of said trochlea of said patient's knee, and generally located opposite said bone-facing surface; articular surfaces, each articular surface having a curvature (J-curve) normally located in a first plane (the sagittal plane) and a second and third plane (coronal and transverse planes). and an ML curve typically disposed on the medial ridge, and each articulating surface of the medial ridge and the lateral ridge can have an offset and a trochlear depth at the second and third surfaces, optionally. A pulley portion that is equivalent to
(c) an articular surface orientation of the trochlear portion of the distal posterior condyle to the distal posterior condyle, which is independent and parallel or obliquely oriented (converging or convergent) in at least one of the planes; ,
(d) a ML condyle optionally integrated between the distal (i.e., distal condylar offset) condylar portion of the distal posterior condyle and the medial and medial articular surfaces of the posterior (i.e., posterior condylar offset) condylar portion; an ML condylar offset, wherein the condylar offset is optionally equivalent between the distal condyle and the posterior condyle;
(e) an ML trochlear offset optionally integrated between the medial ridge and the medial and lateral articular surfaces of the lateral ridge, wherein the trochlear offset an ML pulley offset that is arbitrarily the same as the offset;
Femoral prosthesis consisting of.

whether the sagittal J-curve of at least one articular surface from the distal posterior condyle (medial, lateral) or the trochlea (ridge, trochlear depth) is defined by a single, double, or multiple radius; 40. The prosthetic joint of claim 39 , which fits a patient's unique J-curve.

The sagittal J-curve of at least one of the mediolateral articulation lines is optionally symmetrical and optionally fixed from the distal posterior condyle to the trochlear J-curve (medial and/or lateral ridge, trochlear depth). 41. A joint prosthesis according to claim 39 or 40, arranged at a distance.

Said sagittal J-curve of at least one said line of articulation from said distal posterior condyle (medial, lateral = narrowing angle), or said trochlea (medial ridge and/or lateral ridge, trochlear depth = groove axis in frontal plane, axis 40. A prosthesis according to claim 39 , wherein the (Whiteside line in a plane) is optionally oriented obliquely in at least one of the planes, primarily the coronal plane and the axial plane.

Measurements (including at least AP measurements), shape (including at least condylar offset and trochlear offset, J-curve, and ML curve), and (including at least AP/ML, measurements, narrowing angle, trochlear height, and posterior condylar height) ) a joint geometry and dimensions such that, in terms of contour, at least one of the joint-facing surfaces of the condyle and/or trochlear corresponds to (or closely matches or closely fits) the patient's knee joint surface; 41. The artificial joint according to claim 39 or 40 .

A tangent line connecting the medial and lateral most distal positions of the bone facing surface of the distal portion, a tangent line connecting the medial and lateral most distal positions of the bone facing surface of the posterior condyle, or a tangent line connecting the medial and lateral most distal positions of the bone facing surface of the posterior condyle, or the bone facing surface of the trochlear portion. The artificial joint according to any one of claims 39 to 41, wherein the tangents connecting the medial and lateral most anterior positions are parallel or oblique to each other.

45. The bone-facing surface of claims 39 to 44, wherein the bone-facing surface is a single straight, smooth or beveled surface, or two offset smooth or beveled surfaces, or an offset and curved surface. The artificial joint according to any one of the items.

A prosthetic joint according to any one of claims 39 to 45 , wherein the bone-facing surface is optionally cemented to the bone.

For primary or modified knees (semi-forced or forced, hinged), optionally for cementation, for monobloc or modular components, and typically one of the group of materials consisting of Ti, CrCo, ceramic For the material selected from PS: Postero-Stabilized, UC: Ultra-Congruent, PCR: Posterior Cruciate Retaining, BCR: Bilateral Cruciate Retaining. 47. A joint prosthesis according to any one of claims 39 to 46, corresponding to a different system selected from one of the group of systems consisting of: Bi-Cruciate Retaining.

A method for creating a knee prosthesis from a 3D model selected after applying the method, the method comprising:
(a) analyzing the current and prepathological knee behavior of a patient and the 3D HKA alignment of said patient;
(b) selecting an appropriate 3D model from a comprehensive database of 3D models that optionally uses a planning algorithm to vary the knee morphology, each 3D model being adapted to the known morphology and manufacturing limitations and requirements; And,
(c) creating said selected 3D model that corresponds to a manufacturable, essentially custom knee prosthesis adapted to the 3D structural anatomy of said individual patient, thereby creating a natural-like knee joint; enabling the re-creation of
method including.

a selection program for instructing a processor to carry out the method according to any one of claims 1, 37 to 38, 48, comprising features of a knee prosthesis for receiving input and generating an output. Non-transitory information storage medium.

an encoded selection program implementing a method for instructing a processor to identify characteristics of a knee prosthesis and, when executed, steps to assist a user in selecting a 3D knee prosthesis for a particular patient; A non-transitory information storage medium, the method comprising:
(a) parameterizing the knee prosthesis according to well-defined and independent knee joint compartments ;
(b) 3D of a large number of individual knee samples comprising a model that essentially replicates the movement of the patient's knee by generating a shape that changes said shape parameters (surfaces and dimensions) of at least one said compartment; In the aspect of a 3D knee prosthesis model that replicates shape asymmetry, a large number of knee shapes are generated and the 3D knee is stored in a database that makes it possible to compare the asymmetry of the patient's knee with the asymmetry of the 3D knee prosthesis model. storing the artificial joint models in association with shape parameters and asymmetry of each model;
(c) after learning the patient's pathology and developing prepathological knee prosthesis criteria that meet the patient's needs, optionally using a planning algorithm, searching the database comparing a large number of knee shapes to identify candidate matches;
(d) displaying the candidate matches and their attributes on an output device;
(e) providing a method for selecting a best match from the identified suitable candidate matches;
(f) if the selected knee prosthesis is not in stock, optionally placing a production order;
A medium consisting of

51. The medium of claim 50, wherein the processor is responsive to inputs and outputs communicated to and from a user by the program.