DE2319098A1 - ARTIFICIAL HIP JOINT - Google Patents

Description

Artificial hip joint
(Priority? May 4, 1972 USSB. Mr. 1776053}

The invention relates to artificial hip joints that
surgically inserted as joint prostheses.

It serves to restore the lost mobility of the hip joint as a result of Beohterew's disease, deforming arthrosis, rheumatoid arthritis, aseptic necrosis and
some femoral neck fractures in the elderly.

Artificial hip joints that have an end prosthesis are already known for the acetabulum and an end prosthesis for the proximal one Hip part included, the latter of a head, a neck and a intended for introduction into the hip bone canal Pen insist. Here, the endoprosthesis for the acetabulum can be used both with respect to the outer surface and also with respect to the contact with. ; the head of the end prosthesis intended for the proximal hip part Inner surface can be designed in different ways in terms of construction.

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-2 - 231909?

On the outer surface of the endoprosthesis for the hip socket according to one of the exemplary embodiments for the artificial hip joint, a long screw is provided which is screwed through the hip socket into the iliac wing of the patient. This secures the endoprosthesis in the pelvis. The inner surface of said endoprosthesis for the hip socket is designed hemispherical _$ and the head of · endoprosthesis for the proximal waist portion steeped in it up to its diameter a _f without being held while being "(See the Journal of Bone and .joint _{Surgery? 1968's"} Vol . 5O-B _?

No. 4, pp. 720-731).

This design is disadvantageous characterized in that the head ₈ can be dislocated of the endoprosthesis for the proximal waist portion of the endoprosthesis for the acetabular cup ".

An artificial hip joint is also known, the endoprosthesis of which has spikes on its outer surface for the cantilever flag. These spikes serve to contribute to a better fixation of the endoprosthesis for the acetabulum in the pelvis using cement "(See Acta Orthopedic a BeI-gica, 1965, Vol. 31" No. 5 _S pp. 681-697). The inner surface of this endoprosthesis is designed as a hemisphere to accommodate the head of the endoprosthesis for the proximal hip part «

The design of such a joint also includes one Dislocation of the head of the endoprosthesis for the proximal part of the hip does not result. Another deficiency is the use of ze-

^ment 309845/043 1

_ ₃ - 231909a

The outer surface of the endoprosthesis for the acetabulum can be provided with leaves with openings into which the bone tissue should grow into it. (See copyright certificate No. 278022, class 3Od 1/01, USSE). On the inner surface of the endoprosthesis for the acetabulum there is a recess to accommodate an insert consisting of two halves · The outer surface of this insert resembles the shape of the recess! while the inner surface is spherical and the spherical head of the endoprosthesis for the proximal hip part so that the contact surface larger than the hemisphere of the head.

The deposits discussed serve. to connect the Endoprosthesis for the acetabulum with that for the proximal hip part. This is achieved by upsetting the ends of the insert on the part of the outer surface of the endoprosthesis for the acetabulum · In in this way an inseparable bond is established.

The Kachteile these joints are made "in _s that the joints not possible to incorporate without difficulty in the operation and their components are not interchangeable.

Thus some of the known artificial hip joints are divisible, but they do not prevent the head of the endoprosthesis for the proximal hip part from dislocating from the endoprosthesis for the acetabulum, while the others are inseparable and not only during the operation, but also in the event of a possible dislocation. Replacing one of the components of the artificial hip joint difficult to. are to handle »

309845/0431

The invention aims to eliminate the specified Disadvantage.

The invention is based on the _object to develop a hip joint which is divisible _s can be assembled during the operation and excludes a dislocation of the head of the endoprosthesis for the proximal hip part from the endoprosthesis for the acetabulum «

The object is achieved in _s that in the artificial hip joint, the outer surface thereof is an endoprosthesis for the acetabular cup ₉ intended for attaching with the help of the bone tissue, and has a recess, and an endoprosthesis for the proximal waist portion contains _s a head with a spherical surface which is rigidly connected to the neck of a pin which is intended for introduction into the hip-bone canal _s with an insert being inserted between the surface of the recess and the outer surface of the head, which provides for their articulated connection and has an inner spherical surface which interacts with the spherical surface of the head _- according to the invention, the height of the cavity of the insert formed by the inner spherical surface is smaller than the diameter of the head., and the insert itself in the recess of the endoprosthesis for the The acetabulum is held in place by a self-locking nut, whose head is interlocked The standing surface is designed spherically.

■ - ■■■ 3GS-845/0 & 31

The artificial hip joint designed according to the invention has a number of advantages.

So the endoprosthesis for the patient can Insert the acetabulum and the one for the proximal hip part separately. This separate insertion ensures precise and firm fixation of the endoprosthesis !! guaranteed. Possibly only one endoprosthesis can be exchanged *.

A dislocation of the endoprosthesis for the proximal hip part from the endoprosthesis for the hip arms is thanks to their mutual reliable connection excluded.

In the following wlvä. the invention based on an exemplary embodiment below. With reference to the accompanying drawing, in which an artificial hip joint is illustrated (in partial section) _o

The artificial hip joint according to the invention consists of an endoprosthesis 1 for the hip arms and one Endoprosthesis 2 for the proxissiale hip part together.

The endoprosthesis 1 for the acetabulum has on her Outer surface tiered leaves 3 with beveled Ends and openings 4 into which the bone tissue grows. At a recess 5 is provided on the side of the other surface of the endoprosthesis 1 for the acetabulum. She can consistently like it is reproduced in the drawing or not be continuous. The endoprosthesis 2 for the proximal hip part has a head 6 with a spherical surface, a neck?, a support lug 8 and a

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A pointed pin intended for insertion into the hip-bone canal 9 · The Provide pin 9 with windows 10 «»

The pin 9 has a Bolt 11.

For ■ articulated connection between the endoprosthesis 1 for Biftpfanne and the endoprosthesis 2 for the proxinalen waist portion is located between the head 6 and the recess 5, a liner 12 _e The outer surface of the insert 12 'is similar to the inner surface of the recess 5 s while the inner surface of the Insert 12 is designed spherically «The height of the cavity formed by the spherical inner surface of the insert 12 is smaller by a value" a "than the diameter of the head 6 _O The fastening of the insert 12 within the recess 5 is secured by means of a self-locking nut 13, whose surface interacting with the head 6 is spherical. The outer surface of the nut 13 has a thread which corresponds to the thread of the recess 5 in the area in which the interaction with the nut 13 occurs. To prevent an automatic loosening, the LIuυ ™ ter 13 has a locking device 14. When assembling the endoprosthesis 2 for the proximal hip part during operation, the cutter 13 is screwed onto the neck 7 before the head 6 is pressed in the side of the pin 9 intended for insertion into the hip bone canal.

309845/0431

to be screwed on * In this IPaIIe- one puts ^ after the Nut 13 has been screwed on, if necessary a washer of larger diameter under the support lug 8 »

The nut 13 also has! Wings 15 »which makes it a the operation, it can be screwed more easily and faster

The height and strength of the nut 13 are chosen like this _? that this ensures a reliable connection and an optimal range of motion of the head 6 with respect to the endoprosthesis 1. It is recommended that the height of the nut 13 exceeds the value "a" considerably and that the nut 13 itself and the surface of the last leaf 3 are flush, as the drawing shows.

The artificial hip joint is used during the

Operation applied to the patient in the following way. First, the endoprosthesis -1 for the acetabulum is separated from the endoprosthesis 2 for the proximal hip part from _{5, for} which purpose the self-locking nut 13 is loosened.

One beats the endoprosthesis 1 for the hip arms into one previously formed indentation of the patient's pelvis. Afterward viird the pin of the endoprosthesis for the proximal Hip part in the hip bone canal prepared to the desired size of the sick. The insert 12 of the head 6 is then placed in the endoprosthesis 1 for the hip socket of the endoprosthesis 2. With the nut 13 is the head 6 with the insert 12 attached. After the nut is tightened

it is secured ■

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The proposed artificial hip joint v Performing the operations is made easier, the interchangeability of the components secured and the dislocation of the endoprosthesis for the proximal hip part from the endoprosthesis for the hip phalanx prevents.

3G984S / 0431

Claims (1)

■ l · PATENT CLAIM: Artificial hip joint, which contains an endoprosthesis for the acetabulum, the outer surface of which is intended for fastening with the help of the lineehe ^: tissue, and which has a recess, and an endoprosthesis for the prcximal hip part, which has a head ia with a spherical surface that is rigid is connected to the neck of a pin intended for insertion into the hip-bone canal, with an insert being inserted between the surface of the recess and the outer surface of the head, which provides for their articulated connection and has an inner spherical surface which interacts with the spherical surface of the head, characterized in that the height of the cavity of the insert (12) formed by the inner spherical surface is smaller than the diameter of the head (6), and the insert (12) itself is in the recess (5) the endoprosthesis' (1) for the hip socket by means of a Selbstsichemden nut (13) is held, whose with the. Head (6) interacting surface is designed spherically. Empty e i-t e