JPH07502176A - adjustable hip endoprosthesis - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] adjustable hip endoprosthesis The present invention relates to a hip joint endoprosthesis.

Artificial replacement of the hip joint is one of the most favorable surgical interventions for orthopedic surgeons. Although it is a surgical procedure, there are still many problems associated with artificial joint replacement. is still unresolved even today.

Due to the wide variety of morphological deformities in the femur and pelvis, the forces of the musculature and the leverage of the supporting structures can be reduced. There is almost no correlation between independent arm parameters regardless of physiological interactions (P C Nople, Proximal Femoral Geometry and Cementless Hip Replacement Design of Orthop Rel 5cj 1.86- 92). Many problems arise from this and are currently not completely resolved.

For example, the femoral neck currently has three neck lengths with different sizes. It is only roughly imitated by the product. Adjustment of the center of the head is based on the femur. Depending on the choice of angle between neck and shaft (femoral neck/shaft angle), Recently, for example, the physiological angle of about 1266-130° has been changed to about 140°. This valgus condition is increasingly being chosen. Therefore lower bending & shear on the bed It is required to achieve stress. However, the resulting lateralization of the force It provides high-speed detriction of bread from dry foods. Ru.

Cementless prostheses are known that are optimally attached to the bone and provide uniform force transmission. are expected (Walker (Wa Ik e r) P, Boss (Pos) ) R, O Bertson (Robe r t 5 on) DD, Reill (Reill) y) DT, Ewa 1d FC, Thomas WH, and SI edge CB, design analysis of pressure-fixed lumbar trunk, OSUO Orthop Rel 5ci, 75-85), but However, various head center heights and protrusions are available for optimal attachment to the bone bed. The problem arises of adjusting and permanently fixing it. In this regard, the stability of joint articulation have particular difficulties.

FR-AI-2605514 can adjust the prosthesis head in 3 directions. Discloses a hip prosthesis. For this purpose, the prosthesis is It consists of parts. The prosthesis head is mounted on screws fixed within the femur. It has a cone with a bonded ball on top. The center of the bonded ball and the prote The distance between the center line of the cone and the Adjust. The heights of the centers of the joint balls along the centerline of the prosthesis were different. Adjust by prosthesis head with total height. around the central axis of the prosthesis Rotation supports the prosthesis head in a screw protruding from the prosthesis shaft One rotation means screwing the prosthesis head onto the prosthesis shaft. Fixed by

Furthermore, EP-AI-0390883 describes the use of screws placed on neck parts connected to screws. Discloses a hip prosthesis having a pad component, which includes 1.2 or It can be arranged in a three-dimensionally adjustable manner. in the anterior and/or sagittal plane The displacement is determined by two rails perpendicular to each other, e.g. a dovetail rail. given by id. It also provides tilting and vertical adjustment in the can-like plane. It has been suggested that Adjustment is fixed by screws.

The object of the invention is to provide an improved adjustment that can be adapted to the orthopedic conditions of the patient during surgery. The aim is to provide a hip endoprosthesis that allows for uniformity of forces. Allows transmission and ensures stable fixation of adjustment.

This object is achieved by the invention as defined in the claims. Hip joint end of the present invention The prosthesis allows adjustment of the prosthesis head in the horizontal plane without forming steps. along the tangent to Shenton's line at the medial end. , is possible. According to the invention, the planar direction of the medio-lateral displacement is Parallel to the tangent line starting from the shaped edge and touching the medial internal limit of the neck of the femur Adjust so that it is placed at

The present invention provides a hip joint system that greatly expands the adjustability without replacing individual elements. effectively provide endoprosthesis. The prosthesis is made by removing the prosthesis head during surgery. Adapt to the patient's orthopedic conditions by adjustment. For this purpose, Gradual adjustment of the prosthesis in the medio-lateral direction and rotation around the axis of the femoral shaft. This is possible with a torsion angle of 0. These adjustments are made by the active mouthing and pricking of the teeth. Preferably fixed. These can be removed by external force without active unlocking. Changing the adjustment of the prosthesis is not possible unless these forces are strong enough to break the prosthesis. It is Noh.

These teeth allow you to adjust the position with little force without having to change each other adjustment. It is also possible to adjust the prosthesis separately in the direction of transmission. Fixed both adjustments at the same time In order to Attachment only requires rivets, etc. to connect the main body if possible.

The bonded ball with internal cones of different depths is It is used to adjust the stomach.

All adjustment and fixation means are such that they can be easily assembled by the operating surgeon. It is designed and located in the following manner.

Examples of embodiments of the invention are shown in the drawings and will be described in more detail below.

In the drawing: FIG. 1 shows a femur with an adjustable hip endoprosthesis according to the invention 2 shows a front sectional view of the hip joint endoprosthesis; FIG. 3 shows the line III-II of FIG. FIG. 4 shows a cross-sectional view taken along line I; FIG. 4 shows an upper view seen from the direction of arrow X in FIG.

Figure 1 shows a large hip joint endoprosthesis surrounded by a bone cement covering 2. Femur bone 1 is shown. The endoprosthesis consists of three shafts or stems, one shaft a connecting element or groove element 4 provided and a prosthesis movable with respect to the groove element 4; It consists of 5 heads. This head has a joint ball 6 and a setting or adjusting element 7 , an intermediate plate 8 and a fastening element (which may also be a threaded bolt 10). It has a holding member 9. Mouth formed by front teeth 12.13 and 15.16 The locking means are arranged between the support member 9 and the intermediate plate 8 on the one hand and the groove element on the other hand. 4 and the intermediate plate 8 (FIG. 2). endoprosthesis orthopedics All adjustment means that allow adaptation to the physical environment are indicated by the reference numeral 23 in each figure. hip joint The endoprosthesis is inserted into the femur 2 along the shaft axis S, and is covered with bone cement. Fixed within 2. Eliminate stress concentrations that damage or destroy the bone cement coating 2 Adjustment means 23, including all edge and groove elements 4 of the hip endoprosthesis, are placed as far apart as possible, especially in the medial-lateral end portions of the prosthesis.

At least three adjustment directions are provided for orthopedically precise position adjustment of the joint ball 6. provided to you. The first adjustment is a linear displacement in the medio-lateral direction along line B-B' The second adjustment is made in the lateral direction of one end of the proximal side along the line C-C, and the third adjustment is The node rotates around the axis A-A perpendicular to line B-B' as seen in the front view of Figure 1. Do more.

In FIG. 2 a cross-sectional view of the groove element 4 is shown, which has a central part on the surface facing the head. It has a groove 11 cut downwards in the lateral-lateral direction, into which the adjustment element 7 is guided. do. Due to the downward cut, the adjusting element 7 only transmits linearly in the direction of the groove 11. can be done. A first linear front tooth 12 is arranged on the surface of the groove element 4 .

An intermediate plate 8 is supported on the groove element 4 , an intermediate plate facing the groove element 4 . A second linear front tooth 13 is arranged on the surface of 8, which tooth is similar to the first linear front tooth 1. It forms a pair with 2 and engages with it. The front teeth 12 extend along the length of the groove element 4. and are arranged only on the same side facing the prismatic guide 18 (FIG. 3).

FIG. 2 schematically shows a prosthesis head 5 for explaining the adjustability of the prosthesis head 5. Only the proximal end of the shaft 3 and the groove element 4 are shown. As explained earlier, the groove The edges of the element 4 and the prosthesis shaft 3 are covered with a bone cement coating 2, as shown in FIG. proximal shaft area to prevent concentration of tension and stress that could destroy the It is preferable to place it within.

The holes 25 in the intermediate plate 8 receive the screws 14 of the adjustment element 7. of the locking means 22 The first radial front teeth 15 extend radially from the center of the hole 25 one step higher. 1 disposed on the upper side of the intermediate plate 8 opposite to the second linear front tooth 13; The radial front teeth 15 are confined to an area approximately having the shape of a portion of a circle. Intermediate The rate 8 can widen outward from the groove element 4 in the area of the radial front teeth 15. Wear.

The support member 9 is located on the intermediate plate 8 and the screw 14 of the adjustment element 7 is inserted into the support member 9. Stretch it into the blind hole 26. On the extension of said hole 26, it has a smaller diameter. a hole 27 through which the threaded bolt 10 can be adjusted through the support element 9; It is screwed into the inner thread of the screw 14 of the element 7. The support member 9 has a first radiation On the opposite side of the radial front tooth 15, there is a corresponding second radial front tooth. Said A region defining the second radial front tooth 16 and having the shape of a portion of a circle is defined by the first radial front tooth 16. It occupies a smaller angle than the area defining the radial front teeth 15.

The support member 9 has a shaft carrying an external cone 17 at its end. joining A corresponding internal cone is formed inside the ball 6, and this bonded ball is connected to the external cone. Attach it to the Here, the extent to which the cone 17 penetrates into the bonded ball 6 is called the press-fit depth. It will be revealed. Adjustment in the proximal one end lateral direction by line C-C allows for internal adjustment with different depths. This is done using a joining ball 6 equipped with a cone.

FIG. 3 shows a groove element 4 with a groove 11 and a prismatic guide 18 arranged on the same side. A cross-sectional view is shown. Both guides are introduced above the trunk 3.

In FIG. 1, the neutral or initial position of the center of the bonded ball 6 is indicated by M.

The center of the bonded ball is located at the desired final position parallel to the line B-B' from the above position. can be displaced to the center of rotation of the hip joint.

2 to 4, the neutral position of the center M of the bonded ball 6 is shown as N, which is the first It corresponds to the initial position. The center of the joint ball 6 is from the neutral position N to the limit G1 and G2 (FIG. 2), linear displacement in the direction B-B' is possible. joining The center of the ball 6 has internal cones of different depths in the direction of the line C-C within the limit G3. It can be adjusted in stages by using the joint ball 6 (Fig. 2) with Wear. Finally, up to limits G4 and G5 (Fig. 2), the variation on the arc around axis A-A (Figure 4).

In the configuration of the medial-lateral displacement plane, the angle α is between the line perpendicular to the shaft axis S and the line B-B It stipulates the distance between Line B-B' is the infundibulum of the proximal femoral metaphysis. (position b) or intersects with it. The position is radiation a-p ( Anterior-posterior) can-shaped X-ray image This is a projection of the outer 1-tobe edge. The inside of the line B-B' is point b', which is the point of the femur. It is in contact with the arcuate inner limit of the curved neck. The angle α is 1-15°, preferably 2-15° 100 degrees, more preferably in the range of 2 to 4 degrees. Adjustment for selected angle α Since the displacement of the prosthesis head 5 by the means is not stepwise but follows the Nentons line. Displacement of the prosthesis head along line B-B' allows for uniform transmission of forces .

The hip endoprosthesis is inserted into the proximal femoral funnel of the hip joint with the prosthesis head 5. flat on the tangent line that lies on the lateral edge of the Adjust so that it moves in the medio-lateral direction. Adjustment / Yaft 3 into the femur Preferably, this is done after insertion. However, adjustment of the hip endoprosthesis The operation can also be carried out outside the body with X-ray images, and all necessary adjustments can be made there. I can do it. Additionally, the hip endoprosthesis can be X-rayed independently of the surgical procedure performed. It is possible to pre-adjust on a trial basis based on the image.

In a preferred method, the shaft 3 with the groove element 4 is inserted into the femur 1 and then adjusted. Push the knot element 7 into the groove 11. The intermediate plate 8 and the support member 9 are attached to the adjustment element 7. The screw 14 passes through the hole 25 in the intermediate plate 8 and into the blind hole 26 in the support member 9. It is placed on the groove element 4 so as to be inserted. This arrangement allows the individual parts to intersect with each other. threaded so that it can only be displaced relative to teeth 12.13 and 15.16 It is first fixed by tightening the bolt 10.

Supports the bonded ball 6 selected in advance according to the press-fit depth of the internal cone and the size of the ball. It is attached to the cone 17 of the holding member 9. The cone press-in depth is the center M of the joining ball 6 and the surface of the groove element 4 is determined. Next, from the shaft axis S to the inside of the bonded ball Displace the prosthesis head 5 in the groove 11 along the B-B' direction to the center. Adjust by After rotating the support member 9 around the screw 14 of the adjusting element 7 , fix the adjustment by tightening the threaded bolt 10. With this, one Pairs of teeth 12.13 and 15.16 tighten and positively lock each other This transmits the force acting on the joint ball 6 to the groove element 4 and further to the shaft 3. Ru.

A force that does not act in the axis A-A direction causes the prosthesis head 5 to move around the axis A-A. try to rotate it. These forces are transferred from the support member 9 to the intermediate plate 8 in the second is transmitted through the pair of teeth 15, 16, and from said intermediate plate 8 to the groove element 4. It is transmitted by the rhythm-shaped guide 18. The other force is from the support member 9 to the intermediate plate 8. is transmitted through the screw 14 and from there to the groove element 4 and the prism depending on its direction. It is transmitted through the shaped guide 18 or the first pair of teeth 12.13.

)A Country @ survey 1i4 loss PCT/EP　92101925 Continuation of front page (81) Designated countries EP (AT, BE, CH, DE.

DK, ES, FR, GB, GR, IE, IT, LU, MC, NL, SE), 0A (BP, BJ, CF, CG, C1, CM, GA, GN, N・LL, MR, SN, TD, TG), AU, BB, BG, BR, CA, C3, FI, H.U.

JP, KP, KR, LK, MG, MN, MW, No, PL, RO, RU, SD, US (72) Inventor: Bieber, Ortwin Federal Republic of Germany 71701. Shu Wieberdeingen, Hermann-Etzschihistrasse 26

Claims (16)

[Claims] 1. Hip joint end with shaft (3) and adjustable prosthesis head (5) a prosthesis, wherein the prosthesis head (5) is inside the prosthesis head (5); The plane of unilateral displacement (B-B') is on the lateral edge of the infundibulum of the proximal femur of the hip joint. and parallel to the tangent to the internal contour of the curved neck of the femur. A hip joint endoprosthesis characterized by the ability to articulate. 2. The plane of mediolateral displacement (B-B') is perpendicular to the shaft axis (S) of the prosthesis. The angle α is averagely inclined upward with respect to a straight line, and this angle α is 1 to 15°. The hip joint endoprosthesis according to claim 1, characterized in that: 3. Is the prosthesis head (5) fixable by the locking means (21, 22)? Adjustment element (7) guided in a fixed groove element (4) in a plane of displacement from one side to the other and an adjustment means (23) containing a bonded ball (6) on the adjustment means (23). A support member (9) is attached to the groove element (4) via an intermediate plate (8). The locking means (21, 22) extend through the adjusting means (23). being engageable with each other by at least one fixing element (10) extending therethrough; The hip joint endoprosthesis according to claim 1 or 2, characterized in that: 4. an adjustable prosthesis connected to a shaft (3) fixable in the femur (1); A hip joint endoprosthesis having a prosthesis head, the prosthesis head (5) , guided in a fixed groove element (4), which can be fixed by means of locking means (21, 22). an adjustment means (23) containing an adjustment element (7) which is arranged on the adjustment means (23); The support member (9) of the joint ball (6) is attached to the groove element (4) and The locking means (21, 22) are displaceably supported via the plate (8), and the locking means (21, 22) The adjustment means (23) are secured to each other by at least one fixing element (10) extending therethrough. A hip joint endoprosthesis characterized in that it is engageable with the hip joint endoprosthesis. 5. An adjustment element (7) connects the intermediate plate (8) in a linearly displaceable manner. and a cylindrical screw (14) that axially supports the support member (9). hip endoprosthesis. 6. From the teeth (12, 13 and 15, 16) that the locking means (21, 22) face The first set of teeth (12, 13) are arranged between the support member (9) and the intermediate plate (8). and the second set of teeth (15, 16) are arranged between the groove element (4) and the intermediate plate (8). The hip joint endoprosthesis according to any one of claims 3 to 5, characterized in that . 7. The first set of teeth (12, 13) is such that the linear front teeth (12) are the least of the groove elements (4). both are arranged on one front surface and have corresponding opposite teeth (13) of the intermediate plate (8). 7. The hip joint endoprosthesis according to claim 6, wherein the hip joint endoprosthesis is engaged with the hip joint endoprosthesis. 8. The second set of teeth (15, 16) comprises radial front teeth (1) on the surface of the support member (9). 6) is engaged with the corresponding opposite tooth (15) of the intermediate plate (8). Hip joint endoprosthesis according to claim 6 or 7. 9. An intermediate plate (8) is placed on the groove element (4) with a prismatic guide ( 18) The crotch according to any one of claims 3 to 8, characterized in that the crotch is guided through Joint endoprosthesis. 10. The adjustment element (7) moves on the prismatic guide (18) of the groove element (4) in the plane (B -B') The hip joint according to claim 9, characterized in that it is linearly displaceable in the direction. endoprosthesis. 11. A groove element (4) and a prismatic guide (18) are located in the head of the shaft (3). 11. The hip joint endoprosthesis according to claim 10. 12. Features below: (a) Groove element (4) extends in the medial-lateral displacement (B-B') plane of the prosthesis head. a downwardly cut groove (11) and on the same surface said groove (11); (b) the adjusting element (7) comprises a first linear front tooth (12) perpendicular to said groove ( 11) the cylindrical screw (14) of said adjusting element (7) is threaded inside; (c) an intermediate plate (8) located on said groove element (4); , the hole (25) receives the screw (14) and the second linear front tooth ( 13) engages with the first front tooth (12) of the groove element (4); (d) on the back side of the second front tooth (13), on the upper plane of the plate (8) a first radiation; a radial front tooth (15), said first radial front tooth (15) being located at the center of the hole (25); extending radially from and limited to an area having the shape of a portion of a circle; (e) support material (9) is located on the intermediate plate (8) and the blind hole (26) is located on the adjustment element ( 7), the second radial front tooth (16) receives the cylindrical screw (14) of the plate (8). arranged on the support member (9) to engage the first radial front tooth (15) of the A shaft protruding radially obliquely from the shaft serves as a cord for receiving the joint ball (6). (17); (f) The joint ball (6) is provided with a cone-shaped recess corresponding to the cone, and this The press-fit depth of the curved recess is adjusted according to the manufacturer's procedures; (g) Fixing element (threaded The attached bolt 10) passes through the hole (27) in the support member (9) and enters the inside of the screw (14). In contact with the thread, the fixing elements in the fixed state are the groove element (4), the intermediate plate (8) and and the supporting member (9), and further tighten the mutually opposing engagement locking means (21, 22). attach; and (h) The plane of the medial-lateral displacement (B-B') of the prosthesis head (5) is large on the proximal side. Located on the lateral edge of the infundibulum of the femur and tangent to the internal contour of the curved neck of the femur runs parallel to the tangent line; Hip endoprosthesis with adjustable prosthetic head featuring a combination of Lotese. 13. The plane of medial-lateral displacement (B-B') is relative to the line perpendicular to the shaft axis (S) 13. The structure of claim 12, wherein the curved surface is tilted upwardly by an average of about 1 to 15 degrees. Hip endoprosthesis. 14. Hip joint implant with shaft (3) and adjustable prosthesis head (5) A method for adjusting a prosthesis, in particular when the prosthesis head (5) is adjusted to the base of the hip joint. Located laterally on the lateral edge of the infundibulum of the femur and on the internal contour of the curved neck of the femur The hip endoprosthesis is displaced in a mediolateral direction parallel to the tangent line. The hip joint endoprosthesis according to any one of claims 1 to 13, characterized in that the hip joint endoprosthesis adjusts the How to adjust the thesis. 15. The prosthesis head (5) has a groove element (4) in the medial-lateral direction (B-B') the hip joint end so that it is displaced within and rotated about an axis (A-A) perpendicular to said direction. Adjust the prosthesis, both adjustments being secured through locking means (21, 22) , characterized in that the fixing is performed by tightening the fixing element (10). A shaft fixable within the femur (1) according to one or more of claims 1-13 ( 3) a hip endoprosthesis with an adjustable prosthesis head (5) connected to How to adjust the temperature. 16. In addition to adjusting displacement, the hip endoprosthesis can be adjusted in a mediolateral direction (B- B') and the shaft (A-A) in the side direction (C-C) of one end of the base side. A mating ball (6) is selected from a group of mating balls (6) having different press-in depths. The distance of the joint ball (6) from the surface of the groove element (4) is determined by the press-fit depth. Adjustment of the hip joint endoprosthesis according to claim 15, characterized in that the hip joint endoprosthesis is adjusted by: Method.