166 results about "Hip joint prosthesis" patented technology

An acetabular shell liner having a variable rim surface geometry, which improves range of motion of the femoral component within the liner and decreases the incidence of dislocation and subluxation, and methods of making and using the acetabular shell liner. Prosthetic devices, more particularly hip joint prostheses, containing the acetabular shell liner having a variable rim surface geometry are also provided.

The present invention relates to acetabular cup assemblies for ball-and-socket joint protheses. The acetabular cup assembly is essentially characterized by the fact that it comprises a cup 20 of outside general shape that is substantially hemispherical, the cup including an open hollow housing 21, and an insert 23 in which a hemispherical cavity 24 is made suitable for receiving a spherical head to co-operate in rotation therewith, the insert being of outside shape that is substantially complementary to the housing 21 so as to be capable of being engaged therein, the cup 20 comprising a central base 30 constituting the polar cap of the cup 20, a determined number of cup portions 31-33, and means 34 for associating the cup portions 31-33 at least with the central base 30 to form the cup 20 with its housing 21. The invention is applicable to making a prosthesis, in particular a hip prosthesis or the like.

There is provided an acetabular shell liner, and particularly a constrained liner, having a variable rim surface geometry to improve the range of motion of a femoral component within the liner and decrease the incidence of dislocation and subluxation. There are also provided methods of making and using the acetabular shell liner. Prosthetic devices, and particularly hip joint prostheses, containing the acetabular shell liner having a variable rim surface geometry are also provided.

A femur fixture for a hip-joint prosthesis comprising an intraosseous anchoring structure of a generally circular cross-section for screwing laterally into a complementary bore drilled laterally into the neck of a femur after resection of the femur head to an anchored position. The intraosseous anchoring structure has a proximal end, a distal end, a relatively short frusto-conical proximal section at the proximal end, and a proximal cylindrical section having a screw thread profile thereon. The proximal cylindrical section extends from the frusto-conical proximal section towards the distal end of the anchoring structure. The frusto-conical proximal section and the proximal cylindrical section each being dimensioned so as to bear against the cortex of the femur neck when the intraosseous anchoring structure is in the anchored position. The invention also relates to a set of such femur fixtures, wherein the frusto-conical proximal section and the proximal cylindrical section of each fixture in the set have different dimensions, whereby the fixture in the set having the frusto-conical proximal section and the proximal cylindrical section of correct size for abutting the cortex of the femur neck of a particular patient can be selected for use in that patient.

A flat shaft of a hip-joint prosthesis for anchoring in a femur. The shaft expands on all sides towards a proximal end from a distal end of the shaft and medially merges with a curved section that is continuous with a prosthesis neck. The shaft is additionally expanded in a proximal region along a proximal direction on at least one of an anterior and posterior surfaces.

A hip joint prosthesis with a shaft fastened on the shaft head of which there is a ball head which in turn is inserted in a rotatable manner in the spherical recess of a socket insert and the socket insert is coupled with a hip socket wherein the shaft can be implanted in the femur and the hip socket can be implanted in the pelvic bone. To avoid transmission of vibrations, damping elements of a vibration-damping material are arranged at the coupling points of the shaft head with the ball head and/or of the socket insert with the hip socket.

A temporary neck for a hip joint prosthesis comprising a mechanism that will allow the length of the temporary neck to be varied while in place, during implant surgery and after the stem and base of a permanent prosthesis have been positioned. In one best mode the variation in length is driven by rotating a pinion gear that engages a rack gear connected to the interior of the side walls of a moveable unit, and the ball is connected by a stud to the front wall of the moveable unit; thus the ball moves the same distance as the moveable unit, and that distance is a direct function of gear tooth spacing and number of rotations of the gear. In an alternative mechanism, a threaded drive axle (worm gear) moves in response rotation an adjustment base (wheel gear) in which the base comprises a drive disk with a female, threaded bore. The axle is secured to the pressure disk at one end and free at the other. The position of the drive disk (hence bore) is static; thus as the drive disk rotates and the threads are engaged, the pressure disk moves and the ball moves with it. Both devices include visual references to determine precisely the distance that has been traveled (generally in mm).

A stem (100) for use in a joint prosthesis, such as a femoral stem for a hip joint prosthesis, the stem comprising: a solid central core (102); a proximal outer layer (127) disposed over a proximal portion (101a) of the central core, wherein the proximal outer layer comprises a set of longitudinal ribs (120), defining slots (130) there between; and a distal outer layer made of a deformable porous material disposed over a distal portion (101b) of the central core. The arrangement is such that the stem (100) can be made with a relatively large diameter yet without being excessively stiff, for cementless fixation in osteoporotic patients. The deformability of the distal outer layer also mitigates against the risk of intraoperative bone fractures.

The invention provides a hip joint prosthesis and solves the problems that parts of fastening nails of bone grafts in periacetabular osteotomy interfere with a hip joint prosthesis to cause fixing inconvenience of the bone grafts or the hip joint prosthesis and further to cause the impossibility of reaching an optimum fixing position in the prior art and that an existing total hip femoral prosthesis is not applicable to all DDH (Developmental Dysplasia Of The Hip) patients. The hip joint prosthesis comprises an acetabular cup for fixing inside an acetabulum, an eccentric acetabular liner for increasing the range of motion of the hip joint prosthesis and arranged inside the acetabular cup, a ball heat playing the role of a femoral head and arranged inside the eccentric acetabular liner and a stable femoral stem for being fixed onto a cuboid and connected with the ball head. By means of the above technical scheme, the hip joint prosthesis can be arranged in the optimum fixing position and meets the requirements on prostheses required by operations of the DDH patients.

The present invention relates in certain embodiments to components of a hip-joint prosthesis. More particularly, embodiments of the invention relate to a leaf-like femoral shaft for use as part of a hip-joint prosthesis, and instruments (e.g., a rasp) and methods for implanting the shaft. The shaft includes an anchoring section extending between a proximal region and a distal end of the shaft. The shaft has a cross-sectional contour that defines a lateral side, a medial side, an anterior side and a posterior side. A corresponding rasp is preferably provided for each femoral shaft. The rasp is inserted into the femur to form a cavity having generally the same configuration as the rasp. The shaft is configured to be over-dimensioned in at least one of the anterior-posterior direction and medial-lateral direction relative to the rasped femur cavity. In one embodiment, the distance between diagonally opposite corner junctions of the shaft is substantially equal to the distance between corresponding diagonally opposite corner junctions of the femur cavity, so as to inhibit excess stress on the corticalis.

The invention relates to the field of medical apparatus and instruments, in particular to a non-metal ball hip joint prosthesis.The non-metal ball hip joint prosthesis comprises an acetabulum cup prosthesis body, a non-metal femoral head prosthesis body and a femoral stem prosthesis body.According to the non-metal ball hip joint prosthesis, an original acetabulum cup and liner are changed into a metal cup, and meanwhile a traditional metal or ceramic ball is changed into a high-crosslinking polyethylene ball with a metal core.On the premise that compatibility of the original metal-polyethylene joint surface is maintained, the thickness of the acetabulum cup is greatly decreased, and the large-diameter ball can be used when the small-diameter joint cup is available.Connection among components is reduced, meanwhile, the wear probabilit is greatly lowered, and the defects that a traditional complete hip joint prosthesis is small in movement angle, prone to dislocation and high in acetabulum side bone removal amount are overcome.

The invention discloses a dynamic hip joint prosthesis, and adopts an MDOF (multi-degree of freedom) multi-shaft joint design scheme. The dynamic hip joint prosthesis includes U-shaped components (1), a trunk part (2) and thigh end parts (3), which form a hip forward and backward swing joint and a hip side swing joint. The joint moving range is ensured through bosses (7) on side plates of the U-shaped components (1), the impact when the joints reach limit positions are absorbed through soft baffle blocks (8), the friction force is adjusted through lock nuts (11) and further the joint damping is adjusted; and a sensor (12) is mounted through a sensor support (13), so that the joint angular displacement can be measured in real time. The simulated hip joint model can realize hip joint forward and backward swing and inward and outward swing, the joint damping can be adjusted, a trunk can keep a posture under the condition of no external force, and the motion angle can be measured by the sensor in real time.

The invention provides a metal hip joint prosthesis with a porous layer structure. The metal hip joint prosthesis comprises an acetabulum outer cup, an acetabulum lining, a femoral ball head and a hipjoint femoral stem, wherein the hip joint femoral stem comprises a femoral stem neck part, a femoral stem near end and a femoral stem far end; the upper end of the hip joint femoral stem neck part issleeved by the femoral ball head in cooperation with the acetabulum lining for use; the acetabulum outer cup sleeves outside the acetabulum lining; the contact surfaces of the metal hip joint prosthesis and host bone tissue are of porous structures similar to human bone trabecula in three-dimensional communication; the metal hip joint prosthesis specifically comprises the hip joint femoral stem with a pore layer and the porous acetabulum outer cup; the femoral stem far end is of a whole or surface porous structure; and the pore diameter of the pore layer of the femoral stem far end is smallerthan the pore diameter of the pore layer of the femoral stem near end. The invention also discloses a method for preparing the hip joint femoral stem and the acetabulum outer cup by integrated molding with a 3D printing technology. The metal hip joint prosthesis with the porous layer structure provided by the invention facilitates ingrowth of new bone tissues, and reduces the risk that a pore layer prepared through a surface treatment method is prone to falling off.

The invention relates to a modular hip implant comprising a base that is to be attached to a hipbone, and a socket for accommodating a hip joint prosthesis. The base is provided with fastening means for mounting the base on the hipbone as well as a concave receiving area for the socket. The socket has a convex outer form which is complementary to the receiving area such that the radii of curvature determining the concave receiving area and the convex outer form essentially correspond to each other. The socket can be fastened within the base. The inventive hip implant is characterized in that the base and/or the socket encompass/es means for adjusting the position of the socket relative to the base. The invention allows the inclination and anteversion to be adjusted by arranging the socketinside the base.

A method and a device for helping a surgeon during the application of a determined and known orthopedic surgery protocol, comprising steps of overlaying determined and recorded virtual data, based on 3D markers, so as to allow the surgeon to continuously overlay the virtual spatial information with the actual data of the limbs of the patient.