FR2795626A1 - HIP PROSTHESIS WITH FEMALE COMPONENT AND COTYLOIDAL ELEMENT, WITH LARGE FACILITY OF IMPLANTATION - Google Patents

Abstract

The present invention relates to a hip prosthesis having a femoral component (1) and an associated acetabular element, having great implantability, the femoral element (1) consisting of a shaft (2) which has a distal end. pointed (3) intended to be inserted into the diaphyseal canal of the femur of a patient and a proximal end which is flared and provided with a seat for a separable neck which is intended to connect the femoral component (1) to the element acetabulum. The shaft has, on its outer surface, at the proximal end, several grooves (6) adapted to facilitate osteointegration of the femoral component.

Description

The present invention relates to a prosthesis

  hip having a femoral component and an acetabular element

  dien correspondent, providing a great faculty of im-

  planting. More particularly, the present invention relates to a hip prosthesis having a femoral component.

  ral which adapts to different types of patient's bones.

  We know that hip prostheses are

  with a femoral component, or a stem, which is intended to be inserted into the diaphyseal canal of the femur

  of the patient, a removable collar that can be connected to his ex-

  proximal end, penetrating into the femoral component using its end and having, at the opposite end, a spherical element which is adapted to cooperate with a

  acetabular element which reconstructs the seat of the articu-

  lation of the femur in the patient's pelvic bone.

  An element made of a ceramic or polyethylene is usually interposed between the head

  spherical arranged on the removable collar and the cotton element

  loïdien and makes it possible to avoid the wear of the removable spherical head and consequently to improve the articulation of the femur. Common types of femoral components are provided to suit the diaphyseal canal of the

  femur of the patient in which they are inserted.

  However, depending on the age of the patient, the type of bone is different and therefore has a different response to the insertion of the femoral component. In the case of a young bone, the insertion of the femoral component tends to create a cohesion between the bone and the femoral component, without the need to cement the femoral component to

  inside the diaphyseal canal of the patient's femur.

  If instead the bone is aged, this cohesion is not optimal and therefore the femoral component is cemented inside the diaphyseal canal of the femur,

  as it does if the bone is that of an elderly person.

  Common types of femoral components, which

  are inserted into the diaphyseal canal of the femur after re-

  of a resection of the femur head have an elongated shape in which the distal end, that is to say the end intended to be inserted deeply into the diaphyseal canal of the femur, is shaped so to have a rounded tip, while the proximal part has a flared area in order to adapt to the diaphyseal canal of the femur and especially to block the

femoral component in its seat.

  However, the usual femoral components have the disadvantage that they cannot be easily adapted to the anatomy of the patient's diaphyseal canal, which

  is different for each patient.

  In addition, the acetabular elements used in combination with the femoral components are constituted by hemispherical bodies which have, on their outer surface, several rotation-preventing fins which are formed as elements which protrude radially from of the outer surface of

  the acetabulum, which are located in an indi-

  through the outer surface and reach practi-

  only the edge of the hemispherical body. Through

  diary of this configuration of the fins, on the one hand the acetabular element inserted in the pelvic bone does not perform an involuntary rotation, but on the other hand, because of the angle with which the acetabular element is inserted in

  the pelvic bone, the fins may become partial-

  protrude from the seat of the pelvic bone and through

  therefore come into contact with the surrounding tissue

  rants, deteriorating them accordingly.

  The aim of the present invention is to provide a hip prosthesis having a femoral component and an associated acetabular element, having great implantation capacity and which, thanks to its construction features, can be implanted in patients having

different types of bones.

  Within the scope of the present invention, an object thereof is to provide a hip prosthesis having a femoral component and an associated acetabular element which makes it possible to provide optimum cohesion between the bone and the femoral component without using cement in the case of young patients or using partial or full use of cement in the case of patients

aged.

  Another object of the present invention consists in

  to provide a hip prosthesis having a femoral component

  ral and an associated acetabular element in which the element

  the acetabulum is arranged so as not to deteriorate

  r the surrounding tissue when inserted into the pelvic bone to reconstruct the femoral joint

on the pelvis.

  Another object of the present invention consists in

  to provide a hip prosthesis having a femoral component

  ral and an associated acetabular element, in which the femoral component can be adapted to different types of

diaphyseal canal of femur.

  Another object of the present invention consists in

  to provide a hip prosthesis having a femoral component

  ral and an associated acetabular element, which is very reliable

  ble, relatively easy to manufacture and at low cost

  petitives. This objective, these objectives, as well as others, which will appear below, are achieved by a prosthesis

  hip having a femoral component and a coty-

  associated loidian, having great implantation capacity, the femoral component consisting of a shaft which has a pointed distal end intended to be inserted into

  the diaphyseal canal of a patient's femur and an

  proximal mite which is flared and provided with a seat for a detachable neck which is intended to connect said femoral component to said acetabular element, characterized in that said shaft has, on its outer surface, at the level of

  the proximal end, several grooves adapted for fa-

  cilitate the osteointegration of said femoral component. Other features and advantages of the

  present invention will appear on reading the

  detailed description which will follow preferred modes of

  hip, but not exclusive, prosthesis

  according to the present invention, shown by way of example

  ples non-limiting only in the accompanying drawings, in which: Figure 1 is a view of a first mode of

  realization of a femoral component according to the present in-

  vention, - Figure 2 is a view of a second mode of

  realization of a femoral component according to the present in-

  vention, - Figure 3 is a view of a third embodiment of a femoral component according to the present invention,

  - Figure 4 is a view of the cotyloi element-

dien according to the present invention.

  Referring to the figures above and all

  first in FIG. 1, the femoral component according to the pre-

  invention, indicated in a first embodiment

  tion generally by reference numeral 1, consists of a fitted shaft 2 which has one end

  pointed distal 3 provided with a rounded area 4 in order to

  fish for tip contact with the anterior cortex when the femoral component has been inserted into the canal

diaphyseal of the patient's femur.

  The proximal end of the shape arrangement shaft 2 is provided with a collar 5, the height of which varies according to the dimension of the shaft 2, so as to

  determine a correct distance between the center of rotation

  tion of the joint and the shaft axis 2.

  In addition, tree 2 has, near its zone

  proximal, several grooves 6 which are inclined with respect to

  worn on axis 7 of shaft 2. Said grooves are preferably arranged practically at 45 relative to axis 7 and are provided to improve the osteointegration of the femoral component 1 with the patient's femur. In the case of a young patient or a patient whose bone condition otherwise provides a great capacity for regeneration, the femoral component 1 shown in FIG. 1 is inserted without using cement and the oblique grooves 6 are provided to facilitate osteointegration, allowing

  thus the firm blocking of the femoral component 1 inside

  of the diaphyseal canal of the patient's femur.

  Advantageously, the upper part of the ar-

  bre 2, indicated by reference numeral 8, has a surface finish produced by coarse sanding and is coated

  a layer of hydroxyapatite, so as to facilitate

  core the osteointegration of shaft 2 in said zone.

  Distal area 3, instead, has a finish of

  surface produced by fine sandblasting, without coating layer

hydroxyapatite.

  Figure 2 is a view of a second mode of

  realization of a femoral component according to the present in-

  vention, indicated generally by the reference nu-

  meric 10. In this embodiment, in which identical reference numerals indicate elements identical to those represented in FIG. i and in the figures which follow, the shaft 2 of the femoral component 10 has two lateral pockets 15 which are arranged at level of the proximal end of the shaft 2 and which are provided

  to allow primary stabilization through

  diary of bone cement in the diaphyseal canal of the

Wall.

  The two pockets 15 form a chamber which is

  practically closed in order to put the cement under pressure

  if we. The pockets are formed as parts which are hollowed out from the outer surface of

  shaft 2 and are therefore suitable to be replaced

  plaice of cement, which is injected into a hole 17 by

  through an injector placed in the cavity 16.

  Said cavity is arranged at the proximal end

  male of tree 2 and is connected, in an area located

  downstream, at hole 17 which allows the cement to pass simultaneously

  inside the two pockets 15, so as to fill them when the femoral component 10 has been inserted into

the diaphyseal canal of the femur.

  In addition, the femoral component 10 according to the pre-

  sente invention has at least one channel 18 intended to put

  in the open air and rinse and evacuate each of the pockets 15.

  In practice, the channels 18 make it possible to connect the zone of the pockets 15 to the outside and consequently to insert into said channels tubes which make it possible to rinse and

  to evacuate the pockets 15 and allow the air to escape

  per when cement is injected through hole 17

  to the inside of the pockets 15.

  The surface of the pockets 15 is polished, while the remaining part of the surface of the femoral component 10

  is usually coated with a layer of hy-

  droxyapatite. As in figure 1, tree 2 of figure 2

  includes the rounded zone 4 and the collar 5, the height of which

  tor increases with the size of the tree 2.

  As mentioned, the femoral component 10 is

  used for patients with intermediate bone conditions

  between a bone with a great capacity for regeneration

  tion and a bone with low regenerative capacity.

  The femoral component 10 is actually cemented inside the diaphyseal canal of the femur in an area

  unique which corresponds to the pockets 15 formed on the top

  outer face of the shaft 2 at the level of the proxi-

male of it.

  FIG. 3 represents a third mode of resolution.

  alization of a femoral component according to the present invention

  tion, which, in this case, is generally indicated by the reference numeral 100 and has the distinction of being adapted to be implanted in patients whose bone condition does not ensure good regeneration and for which the femoral component 100 must therefore

  be fully cemented inside the diaphy-

saire the patient's femur.

  In this case, the outer surface of the femoral component 100 is fully polished and the femoral component

has a fitted shape.

  Figure 4 is a view of the acetabulum element.

  dien, which is intended to be connected to the femoral components

  rates previously shown in Figures 1 to 3.

  The acetabular element consists of a hemispherical body

  rique 11 which has a flattened polar region 12 and has, on its outer surface, two fins 13 which are intended to be arranged in a cranial direction and are formed so as to protrude from a practically median zone of the outer surface of the hemispherical body 11 until they reach a

  certain distance from the edge 14 of the hemispherical body

  rique 11, so that they do not protrude from the seat of the pelvis in which the acetabular element is inserted. The presence of the fins in fact makes it possible to avoid unwanted rotations of the acetabular element in the pelvic bone, but at the same time said fins, being

  shorter than the usual fin types, does not

  do not deteriorate surrounding tissue as there is no risk that they will protrude from the bone

  pelvic area in which the acetabulum is received.

  Conveniently, as shown, the element

  acetabulum can in turn receive a hemispherical element

  risk which is intended to receive the head arranged on the

  separable neck, which, in turn, is inserted into the compound

  femoral health. The hemispherical element received in the acetabulum element avoids friction between the element

  acetabulum and the spherical head arranged on the separate neck

  and therefore improves the hip joint and above all extends the life of the prosthesis.

  The acetabular element is inserted into the pel-

  come without cement, using stabilizing fins

  these 13 preventing rotation for fixing

  main and a particular form of exterior surface

  of the hemispherical body 11 for securing

  condaire. In particular, said outer surface is

  of a porous type so as to facilitate bone-

teo-integration.

  More specifically, the exterior surface of the

  hemispherical body 11 which constitutes the acetabular element

  dien is provided via microspheres of

  titanium which consequently provide a po-

reuse.

  Conveniently, the insert, that is to say the hemispherical element which can be received in the hemispherical body 11 of the acetabular element

  is made of ceramic or polyethylene.

  In another embodiment, the surface

  outside of the hemispherical body 11 of the coty-

  Loidian has several holes 20 for the passage of

  screws to fix the acetabulum to the pelvic bone

  come. Conveniently, the outer surface of the hemispherical body 11 can be coated with a layer of hydroxyapatite. In practice, it has been observed that the hip prosthesis according to the present invention fully achieves the intended goals and objectives, since it allows, because of the femoral component, to adapt to different types

  patient's bone, one implantation at a time with

  cement-free, depending on the type of bone condition.

  The acetabular element is also provided with fins which are shorter than the usual types of fin and make it possible to avoid deterioration of the neighboring tissues,

  when implanted into the patient's pelvic bone.

  The hip prosthesis thus designed is suscep-

  tible to undergo many modifications and variations, which are all within the scope of the concept of the present invention, all the details can be replaced by

  other technically equivalent elements.

  In practice, the materials used, for

  as long as they are compatible with the specific use

  that, as well as the dimensions, can be any

  depending on the requirements and the state of the art.

Claims (26)

  1. Hip prosthesis having a femoral component   ral (1) and an associated acetabular element, having great implantation capacity, the femoral component (1; 10; 100) consisting of a shaft (2) which has a pointed distal end (3) intended for be inserted into the diaphyseal canal of a patient's femur and a proximal end which is flared and provided with a seat for a cervix   separable which is provided to connect said femoral component   ral to the acetabulum, characterized in that the ar-   bre (2) has, on its outer surface, at the level of the former   proximal end, several grooves (6) which are adapted   to facilitate the osteointegration of said femoral component   ral. 2. hip prosthesis according to claim 1, characterized in that the grooves (6) are arranged in   forming an angle with respect to the axis of the tree.   3. hip prosthesis according to claim 1,   characterized in that the tree has, at its level   proximal mite, a collar (5) whose height increases   depending on the size of the tree.   4. hip prosthesis according to claim 1,   characterized in that the surface of the shaft (2) at the   calf from the proximal end is finished by sandblasting   coarse and using a coating of hy   droxyapatite, the surface of the tree at the level of the   distal mite (3) being finished by fine sanding.   5. Hip prosthesis according to claim 1, characterized in that the distal end (3) of the shaft   of the femoral component has a rounded area.   6. hip prosthesis according to claim 1,   characterized in that the acetabular element is   killed in a hemispherical body (11) having a polar region   flattened (12), on the outer surface of which are   killed two rotation preventing fins (13) which protrude from a substantially median area of the hemispherical body at a predetermined distance from the edge (14) of the hemispherical body which is most   away from the flattened polar area.   7. hip prosthesis according to claim 6, characterized in that the outer surface of the element   acetabulum has a porous finish.   8. Hip prosthesis according to claim 7, characterized in that the porous finish is provided by   through titanium microspheres.   9. hip prosthesis according to claim 8,   characterized in that the outer surface of the body   the spherical element (11) of the acetabular element has more   holes (20) for the passage of screws intended to fix the acetabular element on the pelvic bone, the surface   being additionally coated with a layer of hy- droxyapatite.   10. Hip prosthesis having a femoral component   ral (10) and a corresponding acetabular element, having great implantation capacity, the femoral component   consisting of a shaft (2) which has a dis-   pointed plate (3) intended to be inserted into the channel   diaphyseal of a patient's femur and a proximal end   flared male provided with a seat for a separable neck which is intended to connect the femoral component to the acetabular element, characterized in that the shaft (2) has on its   outer surface and at its near end   male, two mutually opposite side pockets (15)   in order to provide, by bone cementation, stabilization   main tion of the femoral component.   11. Hip prosthesis according to claim, characterized in that the side pockets (15) are   connected to a through hole (17) whose axis is practi-   only perpendicular to the axis of the shaft, the hole being in turn connected to a cement injection hole (16)   arranged at the proximal end of the shaft.   12. hip prosthesis according to claim 11, characterized in that said proximal end of the shaft has at least one additional pair of holes (18) arranged at the level of said side pockets and connected to these, each of the holes (18 ) allowing insertion   a tube adapted to connect the corresponding side pocket   laying outside the tree.   13. Hip prosthesis according to claim, characterized in that the side pockets (15) are provided with a polished finish, the remaining part of the surface   exterior of the tree being coated with a layer of hy-   droxyapatite. 14. hip prosthesis according to claim 12, characterized in that the shaft (2) has, at its proximal end, a collar (5) whose height   increases with the size of the tree.   15. hip prosthesis according to claim 10, characterized in that the distal end (3) of   the shaft of the femoral component has a rounded area.   16. hip prosthesis according to claim, characterized in that the acetabular element consists of a hemispherical body (11), having a flattened polar region (12), on the outer surface of which are arranged two fins (13) preventing a setting   rotation that protrude from a sensitive area-   median hemispherical body at a pre-   established from the edge (14) of the hemispherical body which   is furthest from the flattened polar region (12).   17. Hip prosthesis according to claim 16, characterized in that the outer surface of   the acetabular element has a porous finish.   18. Hip prosthesis according to claim 17, characterized in that the porous finish is provided by   through titanium microspheres.   19. A hip prosthesis according to claim 18, characterized in that the external surface of the hemispherical body of the acetabular element has several holes (20) for the passage of screws intended to fix the acetabular element on the pelvic bone, the outer surface being   further coated with a layer of hydroxyapatite.   20. Hip prosthesis having a femoral component   ral (100) and a corresponding acetabular element, having great implantation capacity, the femoral component   consisting of a shaft (2) which has a dis-   pointed plate (3) intended to be inserted into the channel   diaphyseal of a patient's femur and a proximal end   male who is flared and provided with a seat for a collar amo-   vible which is intended to connect the femoral component to the acetabulum, characterized in that the shaft has   a polished exterior surface and is intended to be   lying inside the diaphyseal canal of the femur of the pa-   is holding. 21. Hip prosthesis according to claim, characterized in that the shaft (2) has, at its proximal end, a collar (5) whose height   increases with the size of the tree.   22. Hip prosthesis according to claim, characterized in that the distal end (3) of   the shaft (2) of the femoral component has a rounded area.   23. hip prosthesis according to claim 20, characterized in that the acetabular element consists of a hemispherical body (11) provided with a flattened polar region (12), on the outer surface of which are arranged two fins (13 ) preventing a setting   rotation that protrude from a sensitive area-   median hemispherical body at a pre-   established from the edge (14) of the hemispherical body which   is furthest from the flattened polar region.   24. Hip prosthesis according to claim 23, characterized in that the external surface of the acetabular element is provided with a porous finish. 25. Hip prosthesis according to claim 24, characterized in that the porous finish is provided by   through titanium microspheres.   26. Hip prosthesis according to claim 25, characterized in that the external surface of the hemispherical body of the acetabulum element has several holes (20) for the passage of screws intended to fix   the acetabulum on the pelvic bone, the outer surface   being further coated with a layer of hydroxyapa- tite.