DE2311521A1 - PUBLISHING CRITP FILLING BINDING AGENT INTO A BONE - Google Patents

Description

DR. MÜLLER-BORE DIPL-PmS. Ie MANiTZ DIWL.-CHEM. DR. DEUFEL DIPL.-ING. FINSTERWALD dipl-ing. GRÄMKOW

ή received

Munich, D / Hf'- N 1115

NATIONAL EESEAECH DEVELOPMENT OOEPOBATION 66-74 Victoria Street, London S.W.1, England

Device for loading gap-filling Binder in a bone

The present invention relates to binding agent setting, and more particularly to an apparatus for improved setting of prosthetic bone connectors and other implantable devices which are affixed to natural bone by the use of an acrylic or other suitable binding agent.

It is known to provide prosthetic bone connectors by means of stems, ribs and grooves and other configurations secure that suitably prepared in internal medullary canals, preformed holes or other

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Parts in the natural bone can be fixed using acrylic binding agents. The most popular Examples of this can certainly be found between the cases of total hip replacement in which a ball head shaft is glued into the medullary canal of a specifically cut thigh bone for the purpose of interacting with a hemispherical shell which is in a certain cleared area is glued into the hip bone.

Although the practice of binder attachment varies Having advantages over other techniques can sometimes result in mechanical failure difficulties ala the attachment occur and it is an object of the invention to alleviate these difficulties.

There are various causes for failure »One first possible cause is insufficient pressing of the binding agent into the bone and around the certain part of the Device in the gap between this part and the neighboring Khocherij around. In this context it should be noted that current practice is to apply the binder simply by means of a syringe or a to bring another tool to the fastening point and to displace it by pressing the device into the same »

Another cause can result from layering half of the binder, and this in turn can result from a blood-binding agent interface ",

It is now proposed according to one object of the invention » that this causes potential difficulty in delivering the gap-filling binder to a concave excavated point in a bone is diminished by Locate the binder in the site and apply positive pressure to that in an area inside

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binder localized half of the site during the Sealing or covering substantially the whole, or the remaining area of the site to prevent the binder from leaking from the site or reduce.

It should be noted that the proposed pressure applied to the binder is used to convert this into a to press more intimate contact with the bone of the place than is possible with known techniques of the pail, and this applies in particular to a point with exposed porous bone, in the pores of which the binding agent bis migrates to a remarkably deep extent. The exposure also reduces the likelihood of Layering in the binder by shaping it into a body of more homogeneous dispersion while the pressurization "pushes" any blood present to the distal edges of the binder and thereby prevents the possibility of layer-forming blood-binder interfaces within the binder body.

It should also be noted that the invention is principally for use in securing a prosthetic device is provided on a bone and that the invention is described below in this context will be. However, the invention is not limited to this use as there are other circumstances among which the invention is beneficial, for example in building up a weakened by a tumor Bone site.

On every pail and under another, the invention creates a device for carrying out the above

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written procedure. This device has an elongated pressing member for application to which under pressure Binder in the area within the site and an auxiliary element for the placement of the binder around the pressing member to seal substantially all or the remainder of the site or to cover. **

The invention was developed with the intention of using it in conjunction with a hipbone or similar site to use, the or by a prepared bone, surface and a single outermost receiving space completely is limited. In this pail the pressurization of the binder is in all directions to the Desired place and it is accordingly appropriate for the auxiliary element to have a ring-like shape, the sealing around. the extrusion element are connected around can, and to be elastic in order to allow a relatively long movement of the pressing element while it is itself to effect a seal on its circumference um.die site tends to. Currently it is an inflatable one Training of the auxiliary elements preferred.

However, there are other cases where the shape of the body is not the same as the one discussed above, and the more well-known The form of this second type of site is that of a medullary canal, which expands considerably further than that along this required binder penetration. In this case, the penetration is admittedly with Binder in the lateral sense is an important requirement and it is intended to be a pressing element that is tapered in the longitudinal direction to use to exert a wedge-like driving effect on the binder. The assigned auxiliary element is ^ then suitably a rigid plate of U-shape,

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to cover the remaining part of the site while the pressing element gfilit through it, the Plate is moved in order to compensate for changes in the pressing element by the effect of the taper. Preferably the Provide recess in the plate with a resilient seal that is attached around the recess.

The invention is explained below, for example, with reference to the drawing; in this shows:

1 shows a partial longitudinal section through an embodiment of the device according to the invention;

ig. 2 shows a plan view of the device according to Pig. 1; and

Pig. 3 is a schematic representation of another embodiment.

The execution according to the Pig. 1 and 2 were made for 3 use along with the definition of a hip bone component developed during total hip replacement by the so-called Southern Approach; However, it is note that the same general shape or similar porms of this device in other approximations and used for similar prosthetic fixation requirements can be.

Detailed comprises constructing this device, a pressing member having a nose portion 10, generally mushroom-like shape, and a shaft 1 1, which by means of threaded at one end to the free end of the shaft dee of the nosepiece 10, the purpose of co-axial extension of the latter, is in engagement. The other end of the shaft 11 ends in one

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Handle body 12, with the. he is engaged in thread to. to form a substantially T-shaped structure.

The embodiment also includes an inflatable seal assembly with an elastic sealing element 13 in the form of the radially outer part of a bead. The sealing element is arranged around the shaft of the nose part, as shown with a side wall against the The lower surface of the nosepiece head is held by a hanging spacer 14, and the other side wall is through a washer 15 and nut 16 held against the spacer, the spacer being the washer and nut are also arranged around the shank of the nose part and the nut threadedly engaged with the shank stands. ·

The sealing element 13 is formed by a piston and cylinder arrangement inflatable in the handle body 12 with the Inside the sealing element is in communication, namely by means of an axial bore 17 through the shaft 11, a axialeil bore 18, which extends partially along the nose part shaft from its free end, a diametrical one Bore 19 through this shaft, an annular groove 20 around this shaft and a diametrical bore 21 through the spacer 14. The piston and cylinder assembly in the handle. body has two cylinders 22 in the respective counter- ^ set ends of the handle relative to the shaft, which are each aligned parallel to the shaft axis and in the direction of the nasal stalk open. Each cylinder receives a respective piston 23 which at one end of a strip: 24 is attached, which has a cutout in the middle for receiving the shaft. A seal between the pistons and cylinders is effected by the provision of O-rings that extend into the cylinders more extensively. Circumferential

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grooves sit at their open ends.

The cylinders are with the shaft bore 17 through a Bore 26 between them and an axial bore 27 in communication. The bore 26 is in the usual way of one end of the G-riff introduced and then closed at the end by a plug 28, while the Bore 27 runs through the G-reef and at one end threaded on one shaft and one on the other End of a filler cap 29 to receive.

Other components of the design include bolts 30 that are slidable through recesses on the opposite side in question Sides of the shaft 11 for thread engagement with run along the G-riff body 12. These bolts act as stops to limit the outward movement of the pistons from their cylinders.

When using the execution according to the Pig. 1 and 2 is the Space within the sealing element, the cylinder and the bores connecting them are filled with a liquid. The G-riff is then grasped to evacuate the nose part by exerting force over binding agents in the relevant area To apply the cavity while simultaneously pushing the strip towards the G-riff. This The last process pushes the pistons into their cylinders, whereby the liquid inside comes under pressure and that Sealing element for tight engagement with the edge of the cavity expands and stiffens. The nose part can still be move axially forward relative to the inflated seal element and this increases the seal element / cavity engagement, while binding agent is pressed into the adjacent porous bone.

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It is preferred that the liquid used be of the same or medically equivalent form as that for flushing the attachment point so that any leakage remains harmless.

It is also preferred that, with the binder on the fly If the device is used to apply pressure to the lanyard for a minute or two minutes set to cause a good pressing of the binder into the porous hole, while the binder for the purpose of the subsequent inclusion of a prosthetic Component is left sufficiently plastic in this.

^R to be considered Yv aterials: · A prototype of the illustrated embodiment has been quite substantially made of nylon, except the sealing member and the O-rings were made of suitable rubber, and the shank, which was made of aluminum. However, this selection of materials is not critical and others can be used. However, it is useful to consider whether the materials for the rabbit part and the sealing element are easily released from the binding agent pressed by them. If there is any tendency for some of the binding agent to be pulled away after pressing, it is advisable to separate the device and the binding agent by a layer of plastic material that is easily released. ■

In the case of binding an intraporous shaft, such as the thigh component of a total hip replacement, it is preferable that a different form of the device is used for the purpose of the larger press-fit. Fig. 3 shows

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schematically an embodiment of such a device with a substantially U-shaped cover element 40, which consists of two overlapping metal plates 41 with a rubber layer 42 in between. The location 42 has the same U-shape as the plates 41 but extends radially inwardly over the inner circumference thereof Shape out to form a U-shaped elastic rim 43.

The cover element is also provided with an elongated handle 44 provided that protrudes therefrom in the manner shown.

The associated pressing element has the shape of an elongated one tapered shaft 45 »similar to or provided as a femur head or like some other stem-like prosthetic component.

In use, this embodiment Biademittel is brought into the medullary canal of a cut the bone and the cover plate is then attached to the cut side of the bone, with the area defined by the edge 43 of space in assembly over the exposed Ka _n Almund, but offset relative to held. Then the associated pressing element 45 is pushed into the channel while the cover part is continuously moved across the cut bone surface in order to keep the elastic edge in engagement with the shaft. This process will cause increased press-fit of the binding agent into the surrounding bone and around the shaft as the cover plate and its rim reduce any tendency for the binding agent to exit directly from the canal.

- patent claims -

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Sa came in

The device according to the invention is particularly suitable Way for applying a gap-filling binding agent in a concave-shaped part of a bone, whereby the binding agent is placed in the location and positive pressure is applied to the binding agent arranged in a region of the location while substantially all of the remainder of the area of the site is sealed or covered in order to prevent or reduce the escape of the binding agent from the point to the outside.

The device according to the invention is also suitable good for securing a prosthetic device to a bone, leaving a concave-shaped site in the bone prepared and therefore porous bone material on this Place is exposed, in the place a gap-filling binding agent is introduced, the device at this Place is placed and the shaft 'sum pressing the binder is applied to an area within the site while essentially all of the remaining! ? - Area of the place is sealed 'or covered ^ around to prevent the binding agent from escaping to the outside before or during the application of the device to the area! or reduce.

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Claims (8)

Claims Device for loading gap-filling Binding agent that is attached to a concave-shaped location in a bone, characterized by a elongated pressing element, which in the longitudinal direction with the application of force on the binder in an area within is set at this point, and by a recessed auxiliary element for the arrangement around the Pressing member around to seal or cover at least a major portion of the remaining area of the site and to reduce the escape of binder to the outside when this is caused by the attachment of the pressing element is pressurized. 2. Apparatus according to claim 1, characterized in that the auxiliary element is an elastic annular Has seal that can be fixed and sealed close to one End of the pressing element around this is connected to the. 3. Apparatus according to claim 2, characterized in that the sealing element has an inflatable shape. 4. Apparatus according to claim 3 »characterized by a piston and cylinder arrangement for inflating the sealing element, this arrangement being the other Is arranged towards the end of the pressing element and connected by a passage to the sealing element extending through the pressing member and that one of the piston and cylinder components is fixed 309839/0411 connected to the pressing element and the other of these Components with the pressing element for longitudinal movement is coupled relative to this. 5. Apparatus according to claim 4, characterized in that that the pressing element or one of the mentioned components extends further from the sealing element than the said other ingredient, the former is provided with a handle part suitable for manipulation by the palm of the hand and the latter one Has handle part to which the linger can attack and that said arrangement is designed so that the sealing element is inflated by an opposing closing movement of the handle parts. 6. "Device according to one of claims 3 to 6, characterized characterized in that the pressing element has a head portion and a shaft portion which are substantially one Form mushroom shape, and that the sealing element has the shape of the radial outer part of a bead, which is attached around the shaft part behind the head part. 7. Apparatus according to claim 1, characterized in that that the pressing element is tapered towards one end thereof in the longitudinal direction and that the auxiliary element a U-shaped plate with a correspondingly shaped resilient rim extending circumferentially around and radially inwardly from the inner circumference of the plate for wiping engagement around the pressing member with this, during the longitudinal movement "of the same through through the plate. 8. Apparatus according to claim 7, characterized in that 309839/0411 that the pressing element is an intraporous shaft, the part of a prosthetic device ". 309839/0411 Empty soap