Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/32—Joints for the hip
  • A61F2/34—Acetabular cups
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/32—Joints for the hip
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/30767—Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/32—Joints for the hip
  • A61F2/36—Femoral heads ; Femoral endoprostheses
  • A61F2/3609—Femoral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic femoral shafts
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof
  • A61F2002/30316—The prosthesis having different structural features at different locations within the same prosthesis; Connections between prosthetic parts; Special structural features of bone or joint prostheses not otherwise provided for
  • A61F2002/30535—Special structural features of bone or joint prostheses not otherwise provided for
  • A61F2002/30604—Special structural features of bone or joint prostheses not otherwise provided for modular
  • A61F2002/30616—Sets comprising a plurality of prosthetic parts of different sizes or orientations
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/32—Joints for the hip
  • A61F2002/3208—Bipolar or multipolar joints, e.g. having a femoral head articulating within an intermediate acetabular shell whilst said shell articulates within the natural acetabular socket or within an artificial outer shell
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/30—Joints
  • A61F2/32—Joints for the hip
  • A61F2/36—Femoral heads ; Femoral endoprostheses
  • A61F2/3609—Femoral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic femoral shafts
  • A61F2002/3611—Heads or epiphyseal parts of femur
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2220/00—Fixations or connections for prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2220/0025—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
  • A61F2220/0033—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2250/0058—Additional features; Implant or prostheses properties not otherwise provided for
  • A61F2250/006—Additional features; Implant or prostheses properties not otherwise provided for modular
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2310/00—Prostheses classified in A61F2/28 or A61F2/30 - A61F2/44 being constructed from or coated with a particular material
  • A61F2310/00005—The prosthesis being constructed from a particular material
  • A61F2310/00011—Metals or alloys
  • A61F2310/00035—Other metals or alloys
  • A61F2310/00059—Chromium or Cr-based alloys

Definitions

• the present invention relates to the field of joint implants, in particular with dual mobility, and aimed at replacing the bone joints of substantially hemispherical geometry of the human or animal body.
• the small joint is used in low amplitude movements and the large joint comes into action when the femoral neck of the prosthetic stem comes into contact with said constriction of the movable insert during large amplitude movements.
• This contact is described in the literature as being the third joint, often the most fragile.
• ⁇ a series of anchoring cups, the external diameter of which varies discretely and incrementally, in order to adapt to the different acetabular cavities, the standard thickness of which is generally between 2 and 4 millimeters;
• the object of the present invention is to provide a range of joint implant systems which significantly overcome these various drawbacks.
• the invention relates to a range of joint implant systems, said implant being of the type comprising:
• the ratio of the internal diameter of the internal cavity of the anchoring cup to the internal diameter of the internal cavity of the mobile insert, for all the elements of the range, is constant.
• the ratio of the areas of the small joint to the large joint is constant for a chosen ball diameter.
• the respective diameters and surfaces are linked to each other by the classical and well-known relations of the calculation of a sphere, particularly truncated, with regard to the insert.
• the practicing surgeon determines, after the patient's acetabulum has been reamed, the external diameter of the appropriate anchoring cup, in particular in order to conserve as much bone capital as possible.
• This determined anchoring cup will have a thickness such that it respects the aforementioned constant dimensional ratio, so as to reduce the friction torque of the large joint, and consequently further reduce the phenomena of dislocation, in addition to the phenomena of wear liable to to lead, as indicated above, to blockage of the joint and other risks of prosthetic failure mentioned above.
• this ratio is between 1.1 and 3.
• Figure 1 is a schematic representation illustrating a dual mobility joint implant according to the prior art.
• FIG. 2 is a series of sagittal sections of a range of articular implants in accordance with the invention, mainly illustrating the variation in the thickness, in particular of the outer cup.
• Figure 1 shows the block diagram of a dual mobility joint implant according to the prior art.
• this implant consists first of all of an anchoring cup (1), in the shape of a cap, intended to be fixed within a first element of a joint to be prosthesis (2), and for example , the acetabular cavity of a patient's pelvis as part of a hip prosthesis.
• This anchoring cup is made of a rigid biocompatible material, for example of metal such as one-piece chromium-cobalt, or a chromium-cobalt composite with an added thickness of trabecular titanium, for example in order to lighten it.
• This anchoring cup defines an internal cavity of substantially hemispherical shape, defining a first internal surface (SI) of articulation.
• This internal cavity of the anchoring cup is intended to cooperate and receive a mobile insert (3), also made of biocompatible material, and typically of high density polyethylene.
• This movable insert (3) also of substantially hemispherical shape, is therefore intended to be received in the internal cavity of the anchoring cup (1) to form a first ball joint called large joint.
• the external diameter of this movable insert (3) is therefore, except for the clearance, substantially equal to the internal diameter of the internal cavity of the anchoring cup (1).
• This movable insert (3) also comprises an internal cavity, also of substantially hemispherical shape, and defining a second articulation surface (S2), called small articulation, said internal cavity being intended to receive and cooperate with a head or ball (4 ) of spherical shape, secured to another element of the prosthesis joint, in this case, to a femoral rod (5), inserted into the medullary cavity of the femur of the joint in question.
• S2 second articulation surface
• this ball (4) is mounted on a Morse taper located at the end of the neck (7) of the femoral stem (5), in a known manner.
• the femoral stem is typically made made of a rigid biocompatible material such as titanium, cobalt-chromium, stainless steel, etc.
• the base of the movable insert is of flared shape defining a constriction (6), able to cooperate with the frustoconical shape of the neck (7) located at the upper end of the rod (5).
• the dimensions of the anchoring cup (1) are inherent, on the one hand, to the joint considered, with the primary objective of conserving the patient's bone stock, and on the other hand, to the constraints that 'she is meant to endure.
• the outer diameter of the anchoring cups of a range typically varies between 44 and 74 millimeters in 2 millimeter increments.
• the thickness of the anchoring cup of the implants of the prior art is constant in a standard range, and therefore depending on the growth of the external diameter thereof, the articular surface (SI), that is to say of the internal surface of the internal cavity of the anchoring cup, is impacted according to this growth, as is the thickness of the mobile insert. Due to the increase in the thickness of the insert, the articulation surface (SI) increases, and therefore the frictional torque at this level increases; It follows that the wear of the prosthesis at this level also increases for large amplitude movements.
• SI articular surface
• the size of the movable insert will vary, and more precisely its external diameter, in contact with the articulation surface SI, de facto increasing its thickness.
• the choice of insert is naturally deduced, and consequently that of the ball. More practically, for external diameters of the anchoring cup typically between 52 and 74 millimeters, a ball 28 millimeters in diameter will be preferred for the sake of limiting the friction torque at the surface (SI). Once this ball has been selected, there is no more choice as to the insert, the latter being unique for a ball of determined diameter.
• the choice of the anchoring cup in terms of thickness is dictated by the constant ratio sought from the invention of the internal diameter of the internal cavity of the anchoring cup, and in the species of the surface of the joint (SI), on the internal diameter of the mobile implant, and therefore in this case (S2), and typically between 1.1 and 3, advantageously close to 1.6 .
• the range considered comprises only two balls, respectively of diameter 22 or 28 millimeters, and corollary two movable inserts, depending on the diameter of the ball adopted.
• the mobile insert selected (itself dependent only on the diameter of the ball chosen), and on the other hand, the external diameter of the anchoring cup, determined by the acetabular environment observed by the surgeon, the latter is able to choose the most suitable anchoring cup for the desired result while respecting the ratio in accordance with the invention.
• FIG. 2 shows a series of views in sagittal section of different cup / movable insert pairs in accordance with the invention, in which it can be observed that for a given movable insert, in this case suitable for a 28-millimeter diameter ball, the thickness of the anchoring cup increases with the increase in its external diameter, in order to respect the constancy of the ratio of diameters, respectively internal of the anchoring cup and internal of the insert.
• the range of balls (4) is composed of 2 sizes, typically with a diameter of 22 millimeters and a diameter of 28 millimeters for a hip, there are for the range of inserts (3) only two sizes corresponding respectively to the sizes of the balls (4).
• the present invention aims to further significantly reduce the few prosthetic failures of dual mobility implants of the prior art.
• reducing the starting torque differential in the joint between the small and the large joint results in:
• the external surface of the mobile insert is optimized so that, even in anchoring cups of large external diameter, the external surface of said mobile insert remains constant and reduced, thus limiting wear debris can lead to osteolysis and therefore prosthetic failure;
• the literature shows that the number of particles emitted in a hip joint depends, among other things, on said external surface of the mobile insert.
• the simplification of the number of joint implants avoids a number of operating errors, such as resulting from labeling errors or size compatibility errors between the mobile insert and the cup. anchor.

Landscapes

• Health & Medical Sciences (AREA)
• Orthopedic Medicine & Surgery (AREA)
• Cardiology (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Transplantation (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Vascular Medicine (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Prostheses (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=67441309

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Family Cites Families (19)

• 2019
  • 2019-03-01 FR FR1902133A patent/FR3093285B1/fr active Active
  • 2019-07-12 US US16/509,985 patent/US11951011B2/en active Active
• 2020
  • 2020-02-18 WO PCT/FR2020/050297 patent/WO2020178494A1/fr not_active Ceased
  • 2020-02-18 EP EP20710242.7A patent/EP3930633A1/de active Pending

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