DE7237791U - Hut joint socket part for a hut prosthesis - Google Patents

Description

Artur F Is Q here

72 ¹ Jl Tu: r.lingen October O. 1.972

Ju / RB

PM 12'12

Hip joint socket part for a hip prosthesis

The invention relates to a Füftgolenkpfanne for a Hip prosthesis with hemispherical part, the Via fastening means in the hip cavity of the pelvic knee ο c h e j: s b e f e s t i f-b ar is.

Abnormal f- ^: .t on, injuries and diseases of the hip joints.;. v: grounding with partial or complete hip gelc: ':' .-: replacement corrected. For this purpose, the hip joint was replaced by a metallic hip joint socket part and / or a metallic thigh part connected to the hip joint socket part. At. In the most resourceful hip replacement, it is also known to produce part of the joint, preferably the acetabular cup part, from high density polyethylene because of the high friction and excessive abrasion due to the metal-to-keta] contact. Although this can considerably reduce the abrasion and the friction, an abrasion cannot be completely avoided. Thus the exchange is also with this V. 'material' selection:

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ii ^ f. Hu ft ", f ^ p Ί f * v-) <v * Vri ΠΓ! HP 1, ρ ι Ί ί- * s V ^ ??!)! L- ⁱ ? r! P * ^r: unavoidable ^{i "r} ''^tr>7" * Vp Replacing the llüftRelenkpfanne abuts abc} ¹ at the currently conventional method of attachment of the Hfi.ftgelenkpfanne the difficulties,.. v / ith namely Methylmethacrylatzeinent in the Hil.fthi'VL If the cemented-in acetabular cup part has to be replaced, it is necessary to chisel out and grind off all of the methyl methacrylate down to the bone and / to drill a new recess in the pelvic bone. Since this requires a fairly large operation, there is a risk of infection great.

It may also be necessary to replace the acetabulum if foci of infection develop under the ethyl methacrylate cement, which would destroy the bones. draw substance.

Difficulties in the operation thus arise, on the one hand, from the fact that the acetabulum is used to chisel out the acetabulum and the long operating time required to grind out the cement results in an undesirable operation tionstrauina can lead to the patient, and on the other hand by the fact that when cementing a new one The acetabulum is released when the cement hardens, which protects the bone substance and heat of the other neighboring tissue parts must be discharged via coolant.

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The invention is now based on the object of creating a HfSftp ^ lenkpranne z-u that the! Achtoilo the known prostheses, and those at Inf'ectionor. or excessive abrasion in a simple manner and 5 ·. a relatively uncomplicated Oporatior is.

According to the invention this is achieved in that the Jchalteil a covering the edge bulge of the hip cavity Has front flange, which by screwing in fastening screws intraraedull-tr anchorable, in perforation of the front flange recorded dowels can be attached to the beaded edge.

The Küftgeiei kpfänne has a hemispherical shape Shell part, which is used for receiving «· - ^ s spherical head of the Serves the thigh part. The switch part is received by the hip cavity, while a front flange the acetabulum covers the bulge at the edge of the hip cavity. For better support of the front flange you can the unevenness of the edge bead is milled off, so that a flat contact surface is created. Corresponding the height and thickness of the corticalis of the edge bulge are the openings provided for receiving the dowels distributed in the front flange of the acetabulum.

Before inserting the dowels into the bone, first drill the holes for the dowels with the help a drilling device drilled. After these preparatory measures, the acetabular cup with the. Dowels that can be expanded by screwing in a fastening screw,

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air Reckenkneoh ^ n attached. The ·· Ari ^ ahJ öe: for the
depends on height and weight don Hiti

To replace the acetabulum, the head or above o: ine Up.tor] nr.schei be; Ί 5e HuTtgelcnkpfar.ne r ^ rri ^> iochen! Read: "; Eofest i Γ ^ ·" · ί "^ ^π οΙ-λτ. ¹ ;": solved. Then d ^ e Πο1οπ] ··: υΓ ?? πηο out of doi · Huf 1! Κ "':::Koncnmen and through a / new one, of those: Ft Irnf 1; r' r : however the same nurchbruc'ivortoilut"aufv; o :! s · "·: must air. the old joint socket, or.; et;: t. IV! c dura ·; .- fractions par.sen then on the rap; r-rnders from the bone. Flanges of the when replacing the socket im Bone'.n ν · ■■: ■ permanent oubel, M ^ t dern ^?. ^^ '' ^ c ^:> ^^ "pr -) ^;. rir ^ ^ΐ7 .ρ ^% »: · .ν fastening screws in the dowel is the GeloiJci ^ 'anne he; attached to the pelvic bone.

After a further Aus ^ est-iltunn der ^ rf: ir.dun £! ·: "> ■. :: ■ the dowel frontal tip; a polygonal., Vorzufsv: r - ir rectangular flange aufv.'cisen, c ^. he in the kcr.iv ler.;. · designed opening of the front flange of the H "Hr: -! pan engages. This configuration prevents the dowel from rotating at the same time in the breakthrough. des .VV i.rnf lan: · :. ¹ hc: screwing in the fastening screw. In the case of a design of the flange on the dowel and a correspondingly adapted opening in the front flange of the acetabular cup, it is also possible to determine the position of the anchor in relation to the acetabular cup and in particular to the edge of the cup .. specify the Hüfthöhle Pa of rar; '· radially measured is not too thick, is a Aufsr: the anchor of advantage that, ^ entialer Richtur-r Randv in tan ^r Ulst the Hüfthchle proceeds to in this Rr-c.. . · - · available space for the spreading? ^ T so that the danger of rupturing the bone is out of ^ .c; sen.

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As a fastening element for fastening the hip joint]; start at the. Becker.knochen can make a dowel from one; Knot compatible ?. 'chen I'etall, which is formed from a shaft provided with an internal thread and from this shaft extending in the longitudinal direction and half-shell-shaped webs, which when the shaft is drawn in by a fastening screw with radisle buckling behind the
are collapsible.

Axial kinking behind the cortical bone of the bone

Due to the cancellous inner tissue of the bones, dowels are required to fasten the acetabulum, the same as dowels for hollow profiles behind the relatively thin, but stable Corticalis form a bulge. Since a metal compatible with bones is necessary as a square material for the dowels is, the webs at the future kinks with indentations or notches to reduce the bending stiffness or, in order to predefine the direction of bending, be slightly pre-bent. At the Screwing in the fastening screw moves the shaft in the direction of the screw head, whereby the webs Bend radially outwards and, as you tighten further, place yourself on the back of the corticalis. Of the The front flange of the acetabulum is thus between the corticalis and the head of the fastening screw or a Washer clamped and thus held immovable.

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PM 1242

Finally, in a further embodiment of the invention, the fastening screw screwed into the dowel can be used by flaps which can be flanged over the head of the fastening screw and which are attached to a washer are arranged in a ring, be securable. Without securing means it might be possible that the fastening screw loosens and gradually comes off the dowel creates. The attachment of the acetabular cup would be severely weakened as a result.

In the patent drawing, embodiments of the invention are shown.

Figure 1 shows the acetabular cup inserted into the hip cavity and fastened with dowels,

Figure 2 is a plan view of the attached in the hip cavity Acetabulum,

Figure 3 is a sectional drawing of the attachment the dowel used for the acetabulum.

From Figure 1 of the patent drawing it can be seen that a

Full hip joint prosthesis has a thigh part 1 and a hip joint socket part 2. The upper leg section 1 is composed of the ball head portion 3 and an encryption ^f anchoring part 4, with which the thigh part 1 in the femur 5 is inserted and anchored. '

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PM 1242

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The acetabulum 2 has a shell part 6, the shell-shaped recess for receiving the Head 3 of the thigh part 1 is used. For fastening the hip joint arms 2 in the hip cavity 7 of the The cheekbone 8 is provided with an end flange 9 which rests on the edge bead 10 of the hip cavity 7 . To improve the support, the unevenness of the bead 10 can be milled off. For the The front flange has anchoring of the acetabulum 2 distributed over its entire ring surface through openings 11, which serve to accommodate Be.festigungselemente 12. According to the distribution of the openings 11, which is determined by the formation of the edge bead 10 and its ability to Depends on receiving an expansion dowel, the edge bead 10 with holes 13 for receiving the fastening elements 12 provided. To ensure the alignment of the openings 11 and the bores 13 in the bead 10 ensure, it is advantageous to use 13 drilling jigs for the production of the holes.

After these preparatory actions, the dowels are pushed through the openings 11 of the end flange 9 of the acetabular socket 2 into the bores 13 in the bead 10 of the pelvic bone 8 and anchored by screwing in fastening screws 14. The end flange 9 of the acetabular cup 2 is "" clamped between the corticalis of the edge bulge 10 and the head 15 of the fastening screw I ¹ J or a washer 16 and thus held immovably. To secure

7237791 July 3, 75

PH 12-2

of the fastening screw I ¹ A , the washer Ir still has vertically standing tabs 17 which, after nir.-turning the fastening screw I ^, are rounded around its head.

A possible distribution of the fastening elements 12 be: I the fastening of the joint socket 2 shows the top view according to Figure 2. The width of the end face 9 of the acetabulum 2 varies from case to case depending on Width of the bead 10 between 10 mm and 25 rom.

FIG. 3 shows a possible embodiment of the fastening elements 12 used for anchoring. The fastening element 12 consists of a shaft 19 provided with an internal thread 18 and zv ^{r a} half-shell _; : g formed webs 20, which extend from this shaft 19 starting in the longitudinal direction. The free ends of these two webs 20 are limited by a flange 21 which can have a square or a rectangular cross section. The opening 11 in the end flange 9 of the hip joint socket part 2 is also designed in accordance with the outer contour of this flange, so that the flange 21 fits into the opening 11. This provides an anti-twist protection for the dowel 12 when the fastening screw 1 ^{L is} screwed into the shank of the dowel 12. With a rectangular design of the flange 21, it is also possible to determine the right angle of the dowel 12 within the bead 10. A buckling direction of the dowel 12 which runs tangentially to the edge bead 10 is advantageous. A radially directed buckling could of course

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to blow up the bead it f "her / there its in this Direction measured thickness is small.

Beirr ¹ . Screwing a fastening screw into the shaft 19 of the dowel 12, this shaft 19 moves in the direction of the head of the fastening _{screw 1 ^ 5} se daft the two webs? 0 of the fastening element 12 bend radially outward and axially sanserif behind the corticalis of the bone al ^J .en ^; . In order to ensure the buckling outwards, the webs 20 can be provided with recesses and notches at the future kinks, which reduce the flexural rigidity of the webs 20 in the respective area. The same purpose, however, is already fulfilled by a slight pre-kinking of the half-shell-shaped webs 20, as is indicated in FIG. 3 of the patent drawing.

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Claims (3)

Artur Fischer 72 * 11 Tumlingen 9 October 1972 Ju / RB PM 12 * 12 nsprüche 1. Hip joint socket for a hip prosthesis with a hemispherical shell part which can be fastened via fastening means in the hip cavity of the pelvic bone, characterized in that the shell part (6) has a face flange (9) covering the edge bead (10) of the hip cavity (7); can be fastened to the edge bead (10) by means of dowels (12) which can be anchored intramedullary by screwing in fastening screws (I ^{1 I) and are received in openings (11) of the end flange (9).} 2. acetabulum according to claim 1, characterized in that the dowels (12) have an end face have polygonal, preferably rectangular flange, which in the complementary shaped The opening (11) of the end flange (9) of the hip joint socket (2) engages. 7237791 07/03/75 PM 12 '! 2 3. Ilüft geler. 1-: pf nr.ne after .Aηsι: · ruch 1, dadu ^ - 'h marked, dar * ό' · <: - ·. in ^r 'on dowel (l: -' ^J) screwed Defestir unpn ^ ^ chr'vj.be (l'O duro.h above the: head (15) of the Hofestif.un, "sschr'nur ^£ ( '^ umbörtelba e tab (17), which is arranged on a washer (16) rir: f, f cr ::: 5 £ -r'nd, can be secured. Anchor made a ^{kncchenvertri:} r, ln chon ^v .etall for Rails and drr.l. / the attachment of implants to bones in particular for attaching a Hiii'tgeler:] ··: - socket on the pelvic bone according to claim 1, characterized in that the dowel (12) consists of a. Internal thread (18) provided shaft (19) and vcr, this shaft (19) in L'-Ingsrichtunp; s-'i extensive and half-shell-shaped webs (? 0) are formed is that when pulling in the shaft (1 °) by a fastening screw (1 * 0 under radial Buckling behind the corticalis of the bone can be axially collapsed. 7237791 07/03/75