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FR2528694A1 - Artificial hip medullary joint - incorporates grooves to aid cement distribution on tail of joint section - Google Patents

Artificial hip medullary joint - incorporates grooves to aid cement distribution on tail of joint section Download PDF

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Publication number
FR2528694A1
FR2528694A1 FR8210754A FR8210754A FR2528694A1 FR 2528694 A1 FR2528694 A1 FR 2528694A1 FR 8210754 A FR8210754 A FR 8210754A FR 8210754 A FR8210754 A FR 8210754A FR 2528694 A1 FR2528694 A1 FR 2528694A1
Authority
FR
France
Prior art keywords
joint
tail
medullary
artificial hip
prosthesis
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
FR8210754A
Other languages
French (fr)
Inventor
Alain Tornier
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tornier SAS
Original Assignee
Tornier SAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tornier SAS filed Critical Tornier SAS
Priority to FR8210754A priority Critical patent/FR2528694A1/en
Publication of FR2528694A1 publication Critical patent/FR2528694A1/en
Pending legal-status Critical Current

Links

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
    • A61F2/36—Femoral heads ; Femoral endoprostheses
    • A61F2/3662—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
    • A61F2/32—Joints for the hip
    • A61F2/36—Femoral heads ; Femoral endoprostheses
    • A61F2/3662—Femoral shafts
    • A61F2/367—Proximal or metaphyseal parts of 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
    • 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
    • A61F2002/3082—Grooves
    • 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
    • A61F2002/30884—Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
    • 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
    • A61F2002/3625—Necks
    • A61F2002/3631—Necks with an integral complete or partial peripheral collar or bearing shoulder at its base
    • 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
    • A61F2/46—Special tools for implanting artificial joints
    • A61F2002/4631—Special tools for implanting artificial joints the prosthesis being specially adapted for being cemented

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)

Abstract

The artificial hip joint is equipped with grooves (4, 5) for distribution of the cement used to secure it in place, to give a reinforcing action. It has a network of channels on the side faces of the tail (1) of the joint, each formed by a deep lengthwise groove, from which shallower lateral branches extend in a herringbone pattern. To reduce weight, the joint can be made of titanium.

Description

La présente invention est relative à des perfectionnements apportés aux prothèses de hanche et elle vise plus particulièrement à obtenir sa meilleure adaptation par rapport à l'os à l'aide d'un ciment. The present invention relates to improvements made to hip prostheses and it aims more particularly to obtain its best adaptation with respect to the bone using a cement.

Pour diverses raisons techniques, il a été démontré par l'expérience que l'on a intérêt à diminuer la quantité de ciment utilisée dans les implantations de prothèse de hanche, c'est-à-dire l'épaisseur de la couche de ce ciment disposée entre la queue de la prothèse et la paroi interne du canal médullaire du fémur. Bien entendu, cette couche étant très mince, il est nécessaire que sa répartition soit homogène en particulier sur les deux faces latérales de la queue de la prothèse présentant la plus grande surface. For various technical reasons, experience has shown that there is an advantage in reducing the amount of cement used in hip prosthesis implantations, that is to say the thickness of the layer of this cement. disposed between the tail of the prosthesis and the internal wall of the medullary canal of the femur. Of course, this layer being very thin, it is necessary that its distribution is homogeneous in particular on the two lateral faces of the stem of the prosthesis having the largest surface.

Conformément à l'invention, l'on ménage sur les deux faces latérales en question de la queue d'une prothèse de hanche un réseau de canaux en creux, ledit réseau étant composé d'une gorge principale orientée axialement par rapport à la queue et de branches latérales partant en épi à partir de cette gorge centrale. Bien entendu la profondeur de cette dernière est plus importante que celle des branches latérales. According to the invention, on the two lateral faces in question of the tail of a hip prosthesis, a network of hollow channels is arranged, said network being composed of a main groove oriented axially with respect to the tail and lateral branches starting on the cob from this central gorge. Of course the depth of the latter is greater than that of the lateral branches.

Grâce aux canaux considérés on peut
- d'abord permettre l'évacuation du ciment excédentaire lors de l'implantation ;
- ensuite permettre une meilleure répartition du ciment en question ;
- créer des lignes de renfort dans le ciment
- et enfin diminuer les contraintes entre le métal et le ciment en augmentant la surface d'appui de la prothèse.Thanks to the channels considered we can
- first allow the removal of excess cement during implantation;
- then allow a better distribution of the cement in question;
- create reinforcement lines in the cement
- and finally reduce the stresses between the metal and the cement by increasing the support surface of the prosthesis.

De plus, étant donné que la prothèse est prévue la plus volumineuse possible en ce qui concerne la section de sa queue par rapport à celle du canal médullaire du fémur, des problèmes d'inertie de l'implant lors de la marche viennent contrecarrer une meilleure acceptation de la prothèse par le patient. In addition, since the prosthesis is intended to be as bulky as possible with regard to the section of its tail relative to that of the medullary canal of the femur, problems of inertia of the implant during walking come to thwart a better acceptance of the prosthesis by the patient.

Suivant une autre caractéristique de l'invention, la prothèse est réalisée en titane dont la masse volumique faible permet de résoudre en partie les problèmes de poids tout en améliorant les qualités de l'ensemble composite du fémur et de la prothèse du fait que le module d'élasticité du titane est plus voisin de celui de l'os que le module d'élasticité de l'acier usuellement employé. According to another characteristic of the invention, the prosthesis is made of titanium whose low density makes it possible to partially solve the weight problems while improving the qualities of the composite assembly of the femur and the prosthesis because the module The elasticity of titanium is closer to that of bone than the elastic modulus of the steel usually used.

le dessin annexé, donné à titre d'exemple, permettra de mieux comprendre l'invention, les caractéristiques qu'elle présente et les avantages qu'elle est susceptible de procurer
Fig. 1 est nue vue en perspective d'une prothèse réalisée conformément à l'invention.the appended drawing, given by way of example, will allow a better understanding of the invention, the characteristics which it presents and the advantages which it is capable of providing
Fig. 1 is a naked perspective view of a prosthesis produced in accordance with the invention.

Fig. 2 et 7 en sont 4es coupes suivant Il-Il et 111-111
(fig. 1).Fig. 2 and 7 are 4 sections according to Il-Il and 111-111
(fig. 1).

La prothèse suivant l'invention comprend essentiellement une queue usuelle I destinée à être engagée dans la canal médullaire du fémur et un pivot 2 destiné à recevoir une rotule, non représentée, ces deux éléments étant séparés par un plateau d'appui 3. The prosthesis according to the invention essentially comprises a usual tail I intended to be engaged in the medullary canal of the femur and a pivot 2 intended to receive a ball joint, not shown, these two elements being separated by a support plate 3.

Conformément à l'invention, les deux faces latérales la, lb de la queue 1 sont pourvues d'un réseau de canaux qui comprend une gorge longitudinale 4 partant de l'extrémité de la face considérée et se terminant sous le plateau 3. A partir de cette gorge centrale partent en épi des branches latérales 5 qui débouchent sur les côtés de la face considérée. According to the invention, the two lateral faces 1a, 1b of the shank 1 are provided with a network of channels which includes a longitudinal groove 4 starting from the end of the face considered and ending under the plate 3. From from this central groove leave on the spike lateral branches 5 which open on the sides of the face considered.

On observera que la section transversale concave des gorges centrales 4 est beaucoup plus importante que celle des branches latérales *5, de telle sorte que lors de l'enfoncement de la queue 1 dans le canal médullaire, le ciment préalablement disposé autour de la queue est bien réparti sur toute sa surface tandis que l'excès de ciment est évacué vers le débouché du canal médullaire. It will be observed that the concave cross section of the central grooves 4 is much greater than that of the lateral branches * 5, so that when the tail 1 is pressed into the medullary canal, the cement previously placed around the tail is well distributed over its entire surface while the excess cement is evacuated towards the outlet of the medullary canal.

La prothèse suivant l'invention présente donc une queue dont la section est très voisine de celle du canal médullaire de telle sorte que la prothèse est pesante. C'est la raison pour laquelle elle est préférable- ment réalisée en titane qui présente les deux avantages suivants d'abord permettre la réalisation de prothèses légères, et d'autre part assurer une meilleure homogénéité de l'ensemble composite os-prothèse du fait de son module d'élasticité voisin de celui de l'os. The prosthesis according to the invention therefore has a tail whose section is very close to that of the medullary canal so that the prosthesis is heavy. This is the reason why it is preferably made of titanium, which has the following two advantages, firstly, allowing the production of light prostheses, and secondly ensuring better homogeneity of the composite bone-prosthesis assembly due to the fact of its modulus of elasticity close to that of the bone.

La face convexe de la queue 1 présente au niveau de sa jonction avec le plateau 3 un petit aileron 6 qui permet un ancrage angulaire immédiat de la prothèse par rapport au canal médullaire de l'os, de manière à éviter les risques de rotation de la prothèse lors de sa réduction. The convex face of the tail 1 has at its junction with the plate 3 a small fin 6 which allows immediate angular anchoring of the prosthesis relative to the medullary canal of the bone, so as to avoid the risks of rotation of the prosthesis during its reduction.

Il doit d'ailleurs être entendu que la description qui précède m'a été donnée qu'à titre d'exemple et qu'elle ne limite nullement le domaine de l'invention dont on ne sortirait pas en remplaçant les détails d'exécution décrits par tous autres équivalents.  It should moreover be understood that the above description was given to me by way of example and that it in no way limits the field of the invention from which one would not depart by replacing the execution details described by all other equivalents.

Claims (4)

R E V E N D I C A T I-O N SR E V E N D I C A T I-O N S 1. Prothèse de hanche, caractérisée en ce qu'elle est pourvue de moyens (4, 5) propres à répartir le mieux possible le ciment et à constituer des renforts de celui-ci.  1. Hip prosthesis, characterized in that it is provided with means (4, 5) suitable for distributing the cement as best as possible and for forming reinforcements thereof. 2. Prothèse de hanche suivant la revendication 1, caractérisée en ce que les moyens de répartir le ciment et de constituer des renforts de celui-ci sont réalisés sous la forme d'un réseau de canaux (4, 5) disposés sur au moins les deux faces latérales (la, lb) de la queue (1) de la prothèse. 2. hip prosthesis according to claim 1, characterized in that the means for distributing the cement and for constituting reinforcements thereof are produced in the form of a network of channels (4, 5) arranged on at least the two lateral faces (la, lb) of the tail (1) of the prosthesis. 3. Prothèse de hanche suivant la revendication 2, caractérisée en ce que chaque réseau de canaux comprend une gorge longitudinale profonde (4) à partir de laquelle partent en épi des branches latérales (5) de plus faible profondeur débouchant sur l'extérieur. 3. Hip prosthesis according to claim 2, characterized in that each network of channels comprises a deep longitudinal groove (4) from which the spikes of lateral branches (5) of shallower depth open out onto the outside. 4. Prothèse de hanche suivant la revendication 1, caractérisée en ce qu'elle est réalisée en titane de manière qu'elle présente un poids réduit.  4. Hip prosthesis according to claim 1, characterized in that it is made of titanium so that it has a reduced weight.
FR8210754A 1982-06-16 1982-06-16 Artificial hip medullary joint - incorporates grooves to aid cement distribution on tail of joint section Pending FR2528694A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR8210754A FR2528694A1 (en) 1982-06-16 1982-06-16 Artificial hip medullary joint - incorporates grooves to aid cement distribution on tail of joint section

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR8210754A FR2528694A1 (en) 1982-06-16 1982-06-16 Artificial hip medullary joint - incorporates grooves to aid cement distribution on tail of joint section

Publications (1)

Publication Number Publication Date
FR2528694A1 true FR2528694A1 (en) 1983-12-23

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4964865A (en) * 1988-02-03 1990-10-23 Intermedics Orthopedics, Inc. Glenoid prosthesis and method of use
FR2697152A1 (en) * 1992-10-23 1994-04-29 Vidal Philippe Femoral shaft component for total hip joint replacement prosthesis - comprises elongate shaft with lateral longitudinal grooves at distal end to promote flow of bone cement during implantation

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2146253B1 (en) * 1971-09-06 1973-03-01 Gebrueder Sulzer Ag, Winterthur (Schweiz)
FR2199967A1 (en) * 1972-09-21 1974-04-19 Telectronics Pty Ltd
DE2607315A1 (en) * 1975-02-28 1976-09-02 United States Surgical Corp STEM FOR ARTICULATED PROSTHESIS
FR2493139A1 (en) * 1980-06-30 1982-05-07 Tornier Sa Artificial ball end of hip joint ball - with variable overall dimensions to suit specific joints

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2146253B1 (en) * 1971-09-06 1973-03-01 Gebrueder Sulzer Ag, Winterthur (Schweiz)
FR2199967A1 (en) * 1972-09-21 1974-04-19 Telectronics Pty Ltd
DE2607315A1 (en) * 1975-02-28 1976-09-02 United States Surgical Corp STEM FOR ARTICULATED PROSTHESIS
FR2493139A1 (en) * 1980-06-30 1982-05-07 Tornier Sa Artificial ball end of hip joint ball - with variable overall dimensions to suit specific joints

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4964865A (en) * 1988-02-03 1990-10-23 Intermedics Orthopedics, Inc. Glenoid prosthesis and method of use
FR2697152A1 (en) * 1992-10-23 1994-04-29 Vidal Philippe Femoral shaft component for total hip joint replacement prosthesis - comprises elongate shaft with lateral longitudinal grooves at distal end to promote flow of bone cement during implantation

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