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
  • A61F2/38—Joints for elbows or knees
  • A61F2/389—Tibial components
• • 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
  • A61F2002/30108—Shapes
  • A61F2002/3011—Cross-sections or two-dimensional shapes
  • A61F2002/30159—Concave polygonal shapes
  • A61F2002/30179—X-shaped
• • 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
  • A61F2002/30329—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
  • A61F2002/30405—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements made by screwing complementary threads machined on the parts themselves
• • 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
  • A61F2/30771—Special external or bone-contacting surface, e.g. coating for improving bone ingrowth applied in original prostheses, e.g. holes or grooves
  • A61F2002/30841—Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
  • A61F2002/30845—Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes with cutting edges
• • 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
  • A61F2/30771—Special external or bone-contacting surface, e.g. coating for improving bone ingrowth applied in original prostheses, e.g. holes or grooves
  • A61F2002/30878—Special external or bone-contacting surface, e.g. coating for improving bone ingrowth applied in original prostheses, e.g. holes or grooves with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts

Definitions

• the present invention refers to a non-cemented tibial component that can be decomposed for a knee prosthesis implant.
• knee prosthesis surgery has strongly evolved in the last years, dealing with the need of patients of having a quicker re-education and a lower intervention invasiveness.
• a surgeon therefore has more and more refined surgical techniques available, which allow him to safely perform the knee prosthesis intervention.
• the knee prosthesis replacement intervention provides to intervene on femur and tibia components by implanting elements that functionally replace these two components of the physiologic articulation: currently, the art proposes to use a tibial component composed of a metallic support plate equipped with a projection to be inserted inside a medullary tibia recess, such plate being adapted to be articulated with the femur component by interposing a suitable spacer (or insert) generally made of polyethylene.
• the prosthesis that is applied to patients with a good health is the non-cemented one, secured only through pressure so that the biologic bone- integration phases, helped by the materials with which the prosthesis is coated or directly produced, are those that perform the final 'joining'.
• obtaining the primary plant stability is a process that requires time, since it is demanded to the degree of obtained bone-integration.
• possible revision interventions of the implant are more complex and invasive.
• object of the present invention is solving the above prior art problems by providing a non-cemented tibial component that can be decomposed for a knee prosthesis implant that allows obtaining an immediate primary stability of the implant itself.
• Another object of the present invention is providing a non-cemented tibial component that can be decomposed for a knee prosthesis implant that allows an easy revision of the implant whenever necessary .
• Figure 1 shows a front view of a preferred embodiment of a first element of the tibial component according to the present invention
• Figure 2 shows a top view of the element of Figure 1;
• Figure 3 shows a side view of the element of Figure 1;
• Figure 4 shows a front view of a preferred embodiment of a second element of the tibial component according to the present invention
• Figure ⁇ 5 shows a top view of the element of Figure 4.
• Figure 6 shows a side view of the tibial component according to the present invention once having been assembled
• Figure 7 shows a front view of the tibial component of Figure 6.
• the non-cemented tibial component 1 that can be decomposed according to the present invention for a knee prosthesis implant is composed of at least one tibial plate 3 and of at least one tibial stem 5, such tibial plate 3 being equipped with at least one connection seat 7 for such tibial stem 5.
• a lower surface of the tibial plate 3 adapted to be overlapped to the tibial plate of the bone head of the tibial bone is equipped with at least two projections 13: in particular, such projections 13 are equipped with a suitably sharpened profile adapted to make it easier to insert it inside the bone material of the tibial plate, and are developed along the major transverse axis T-T of the tibial plate 3 in diametrically opposite positions with respect to the seat 7.
• the projections -13 are suitably slanted with respect to an axis P-P orthogonal to the lower surface of the tibial plate 3, and frontward with respect to the longitudinal axis of the tibial bone, in a side projection once having implanted the tibial plate 3 itself, by an angle a, such angle a being preferably equal to 30°.
• Such front slanting is advantageously aimed to contrast the stresses developed by the rotation of the femur component of the knee prosthesis implant when walking, with a mainly backward-frontward direction.
• the external surface of the tibial stem 5 is smooth, and, moreover, the seat 7 is internally equipped with at least one first threaded portion 9 adapted to be engaged with a corresponding second threaded portion 11 made externally to the tibial stem 5 when connecting the tibial plate 3 to the tibial stem 5 itself.
• this latter one has its own longitudinal axis L-L in a substantially parallel position to the axis P-P, and therefore oriented along the longitudinal axis of the tibial bone .
• Assembling of the tibial plate 3 and the tibial stem 5 on the suitably prepared tibia therefore allows advantageously obtaining a primary (immediate) stability of the implant due to the different axes of the action exerted on the tibial bone by the projections 13 and the stem 5 itself.
• the secondary stability derived by the bone integration can be obtained by covering part of the surfaces in contact with the bone with the material that will be deemed most suitable, such as, for example, plasma spray, hydroxy-apatite, etc.
• the tibial component 1 according to the present invention as previously described further allows an easy implant revision when necessary: in fact, the tibial stem 5 can be removed from the tibial bone with torsion stresses that are more efficient than the traction stresses necessary for removing the tibial components of the prior art implants: moreover, the tibial plate 3 without the tibial stem 5 allows an easier aggression of the lower bone-integrated surface through a tangential ungluing .

Landscapes

• Health & Medical Sciences (AREA)
• Orthopedic Medicine & Surgery (AREA)
• Physical Education & Sports Medicine (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=43975600

Family Applications (1)

Country Status (2)

Citations (18)

• 2011
  • 2011-01-14 IT ITTO2011A000017A patent/IT1406772B1/it active
  • 2011-12-27 WO PCT/IT2011/000419 patent/WO2012095879A1/en active Application Filing

Patent Citations (18)

Also Published As

Similar Documents

Legal Events