CROSS REFERENCE TO RELATED APPLICATIONSThis application is a divisional of application Ser. No. 10/578,734, filed May 10, 2006, allowed July 27, 2010, which is a National Stage Entry of PCT International Application No. PCT/SE2004/001626, filed Nov. 10, 2004, which claims the benefit of priority of Swedish Application No. 0302983-2, filed Nov. 11, 2003. All of the above listed applications are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTIONThe present invention relates to a device for providing spongy bone with bone substitute and/or bone reinforcing material, wherein at least one perforating device is provided for making at least one hole in the spongy bone and wherein at least one flushing or rinsing device is provided for flushing or rinsing the hole with a rinsing agent. The invention further relates to a bone substitute and/or bone reinforcing material and a method.
BACKGROUND OF THE INVENTIONVertebroplasty is a technique according to which biocompatible material is injected into a spongy vertebra. After some time, the injected material hardens, whereby an inner support is obtained for fixing the vertebra and thereby alleviate pain and reduce the risk of vertebral collapse.
The material is injected into the vertebra through a needle and in doing so, it is necessary to subject the material to high pressure, often one or more MPa. Hereby, there is an obvious risk that tissue material, e.g. blood and fat, in the vertebra is pressed out into the blood vessels or into fracture gaps such that said material can affect adjacent nerves. There is also an obvious risk that the injected material is pressed out into fracture gaps or into adjacent tissue. This is well known and the material and fat being pressed out can reach the blood vessels and the lungs, resulting in a poorer oxygenation, blood pressure reduction and, in exceptional cases, death.
By inserting an extra needle into the vertebra, the risk of leakage (note publications in the enclosed reference list,point 1 and 2, in the end of the description). Normally, this extra needle is left open or preferably connected to a suction hose for generating a suction effect (note publication in the enclosed reference list, point3). However, any decisive effect is not reached with the prior art.
Various hole making and rinsing devices for making holes in and rinsing of vertebrae are known from e.g. U.S. Pat. No. 6,440,138, U.S. Pat. 6,716,216, U.S. Pat. No. 6,719,761 and U.S. 6,740,090, but none of these publications describes generation of a vacuum in the vertebrae for providing safe suction of bone substitute and/or bone reinforcing material into said vertebrae.
SUMMARY OF THE INVENTIONThe object of the present invention has been to eliminate the abovementioned problem and this is arrived at while the invention has been given the characterizing features of each of the subsequent claims.
By making a hole in the spongy bone and rinse it, tissue material and other material can be flushed away from the hole and the sides thereof, such that said sides get rough or uneven surfaces with depressions into which the bone substitute and/or bone reinforcing material can be brought to penetrate by generating a vacuum in the hole and without risking that said bone substitute and/or bone reinforcing material penetrates into the blood paths.
BRIEF DESCRIPTION OF THE DRAWINGSThe invention will be further described below with reference to the accompanying drawings, in which:
FIG. 1 is a schematic view of a device according to the invention when making a hole in a spongy vertebra shown in section;
FIG. 2 illustrates parts of the device ofFIG. 1 during flushing or rinsing of the hole made in the spongy vertebra;
FIG. 3 illustrates parts of the device according to the invention during suction of bone substitute and/or bone reinforcing material into the vertebra;
FIG. 4 is a sectional view of a spongy vertebra in which bone substitute and/or bone reinforcing material has been injected with pressure through a needle according to prior art; and
FIG. 5 is a sectional view of a spongy vertebra into which bone substitute and/or bone reinforcing material has been sucked by means of a device according to the invention.
In the figures, different parts of a device for preparingspongy bone1, e.g. avertebra2, to receive bone substitute and/orbone reinforcing material3, and for locating said material in said vertebra is schematically illustrated. Said device comprises at least one perforating device4 for making at least onehole5 in thevertebra2, at least one flushing or rinsingdevice6 for flushing or rinsing said hole withrinsing agent7 and at least one supply device8 which permits suction and/or insertion of bone substitute and/orbone reinforcing material3 into the vertebra.
At least onevacuum source9 is provided to generate a vacuum in thehole5 in thevertebra2 for sucking and/or facilitate insertion of bone substitute and/orbone reinforcing material3 into said vertebra.
The perforating device4 can be designed in many different ways and so can also therinsing device6. At the exemplary embodiment ofFIGS. 1 and 2, the perforating andrinsing devices4,6 are combined to adevice10 including anouter tube member11 which can be located at thevertebra2. In thetube member11 there is provided a perforatingmeans12 which is movable relative to said tube member in coaxial and/or rotary direction. The perforatingmeans12 has and/or cooperates with aperforating member13 which can be designed in many ways. As an example of aperforating member13, it is shown an end portion of the perforatingmeans12 which can be retracted into theouter tube member11 when this is located at thevertebra2 and which is bent when it is expelled out of said pipe member. When the perforatingmeans12 is rotated, thebent perforating member13 will make thehole5 in thevertebra2.
The movements of the perforating means12 can be obtained by means of adrive unit14 of a suitable type.
At the exemplary embodiment, the perforatingmeans12 is designed as aninner tube member15. Arinsing agent container16 is connected to thisinner tube member15 through a connectingdevice17 which permits feeding ofrinsing agent7 from thecontainer16 into theinner tube member15 irrespective of whether said inner tube member is rotatable or not. Alternatively, therinsing agent container16 may be connected to theouter tube member11 and thecollecting device27 and thevacuum source9 to theinner tube member15, such that theouter tube member11 can leadrinsing agent7 into thehole5 and be sucked out of said hole through theinner tube member15. The perforating device4 is used preferably for making at least twoholes5 in thevertebra2. Theseholes5 are located such that they communicate with each other either by extending into each other (as is illustrated inFIG. 3) or by havingspongy bone1 between them since such bone is pervious to air and can be provided with bone substitute and/orbone reinforcing material3.
Thevacuum source9 is provided to suckrinsing agent7 through thehole5 and it is preferably connected to theouter tube member11 for sucking, through said outer tube member,rinsing agent7 and tissue material and other material out of saidhole5.
Between theouter tube member11 and thevacuum source9 there is preferably a collectingdevice27 for collectingrinsing agent7 and tissue material and other material brought along therewith out of thehole5.
Therinsing device6 is preferably provided also to flush or rinse thesides5aof thehole5 such thatdepressions5band similar are formed therein while tissue material and other material is flushed off said sides. This is advantageous since bone substitute and/orbone reinforcing material3, by means of the vacuum generated in thehole5, can be brought to penetrate into thedepressions5b.
At the embodiment illustrated inFIG. 3, theouter tube member11 has its equivalent in a first cannula orneedle19 which can cooperate with a perforating device (not shown) for making afirst hole5 in thevertebra2. A second cannula orneedle20 is connected to avacuum source9 and this second cannula can also cooperate with a perforating device (not shown) for making asecond hole5 in thevertebra2.
The supply device8 illustrated inFIG. 3 may have acontainer18 for mixing various components for production of bone substitute and/orbone reinforcing material3 and/or for storage thereof. Thecontainer18 is connected or connectable to a first cannula orneedle19 which can be inserted into thevertebra2 and which is adapted to lead bone substitute and/orbone reinforcing material3 into theholes5 in thevertebra2. A second cannula orneedle20 can be inserted into thevertebra2 and is connected to thevacuum source9, which is adapted to generate a vacuum in theholes5 such that bone substitute and/orbone reinforcing material3 is sucked into said holes and/or for facilitating insertion or feeding of said material into said holes.
Thevacuum source9 can be aninjector pump21 which is run or driven by a suitable compressed medium from a compressed-medium device22. Theinjector pump21 may e.g. be driven by compressed air and connected, through a compressed-air conduit23, to a compressed-medium device22 in the form of a compressed-air device. This device may be built into a hospital or other locality in which theinjector pump21 shall be used. Alternatively, theinjector pump21 can be run or driven by another commercially available gas as is indicated with broken lines inFIG. 3.
The compressed-medium device22 can operate theinjector pump21 with a compressed-medium pressure of 4, 5-8, 5 bar and theinjector pump21 may be of a type which is placed on the floor and which has afoot pedal24 for its operation. Thus, theinjector pump21 can be started by tilting thefoot pedal24 in one direction and stopped by tilting thefoot pedal24 in the opposite direction. As an example of ausable injector pump21 in this connection one can mention an injector pump of the type used for producing bone cement as defined in U.S. patent specification 5,328,262 and sold under the product name Scan Vacuum Pump™ by the company Scandimed International AB, Sjöbo, Sweden.
Theinjector pump21 is preferably provided to generate a vacuum in all theholes5 of thespongy bone1 such that said holes are filled or can be filled with bone substitute and/orbone reinforcing material3 and/or a vacuum such that the bone substitute and/orbone reinforcing material3 is distributed therein, preferably without any or any substantial portions thereof being sucked into thesecond cannula20.
Theinjector pump 21 can be provided to generate a vacuum of between −0.5 bar and −0, 92 bar in thespongy bone1, which vacuum corresponds to a 70% and 90% absolute vacuum. In many cases it is sufficient that theinjector pump21 generates a vacuum of between −0.7 bar and −0.8 bar in thespongy bone1.
Theinjector pump21 is preferably provided to suck tissue material such as blood and fat out of theholes5 of thespongy bone1 and into thesecond cannula20 before bone substitute and/orbone reinforcing material3 is sucked into thespongy bone1 through thefirst cannula19.
In at least one connectingconduit25 between the second cannula20 (the inlet end of which is the end which is inserted into ahole5 of the spongy bone1) and theinjector pump21, there may be provided anon-return valve device26 and/or a collectingdevice27 and/or a monomer filter28 (if the bone substitute and/orbone reinforcing material3 is of bone cement type) and/or abacteria filter29.
The collectingdevice27 may be a container which is placed on the floor and closed or sealed by means of a cap. A portion of the connectingconduit25, which is connected to thesecond cannula20, is directed through the cap and a small distance down into the container. Another portion of the connectingconduit25 is also directed through the cap and a small distance down into the container. When tissue material is sucked from theholes5 of thespongy bone1 to the collectingdevice27, said material is collected down below in the container and is therefore prevented from being sucked further towards theinjector pump21 and into said pump. If there is amonomer filter28 and/or abacteria filter29 between the collectingdevice27 and theinjector pump21, the tissue material is prevented also from being sucked thereto.
Themonomer filter28 may be a carbon filter and is adapted to prevent monomer gases, generated during production of bone substitute and/orbone reinforcing material3 in the form of bone cement, from being sucked into theinjector pump21 and discharged to the surroundings. The advantages with such amonomer filter28 are described in the publication according to the enclosed reference list, point4. The bacteria filter29 is provided to prevent bacteria from entering or getting into theholes5 of thespongy bone1 if the connectingconduit25 is opened or opens unintentionally and air is sucked therethrough to theholes5 if there is a vacuum therein.
Themonomer filter28 and bacteria filter29 may be provided in that portion of the connectingconduit25 which connects the collectingdevice27 with theinjector pump21.
Thenon-return valve device26, which preferably can be provided in the connectingconduit25 between the collectingdevice27 and thesecond cannula20, is adapted to prevent tissue material from being sucked out of the collectingdevice27 and into theholes5 of thespongy bone1 if the connectingconduit25 is opened or opens unintentionally such that a suction is generated therein towards theholes5 of thespongy bone1 if there is a vacuum therein.
Thecontainer18 may include afeeding device30 for feeding bone substitute and/orbone reinforcing material3 out of thecontainer18 and into theholes5 of thespongy bone1 at the same time theinjector pump21 generates a vacuum therein or thereafter.
Thefeeding device30 is schematically illustrated with a feed means31 which is displaceably mounted relative to thecontainer18 and which can be displaced manually for discharge of bone substitute and/orbone reinforcing material3 from thecontainer18 and through thefirst cannula19 into theholes5 of thespongy bone1.
Thecontainer18 may eventually be used as mixing container for mixing the components required for the production of such bone substitute and/orbone reinforcing material3 that can be brought to harden after insertion thereof into theholes5 of thespongy bone1. This mixing can occur with a mixing means or in any other way. Such a mixing means can preferably be moved manually back and forth in thecontainer18 and is eventually rotated relative thereto for mixing the components.
Avalve device32 may be provided for, on one hand, close or interrupt the supply of bone substitute and/orbone reinforcing material3 through thefirst cannula19 to theholes5 of thespongy bone1 until theinjector pump21 has generated a suitable vacuum therein. When this is done, thevalve device32 may be opened for permitting suction of bone substitute and/orbone reinforcing material3 into theholes5 of thespongy bone1 by means of theinjector pump21. Thevalve device32 may be located on thefirst cannula19 or on a connecting conduit between thecontainer18 and thefirst cannula19. Thevalve device32 may be manually operable by means of acontrol handle33.
As an alternative to the embodiment of the flushing or rinsingdevice6 described above, said device may be combined with the supply device8. At this alternative, the rinsingagent container16 of therinsing device6 may be connected to thefirst cannula19 e.g. through thevalve device32 which in this case can be a three way valve permitting either that the supply of rinsing agent to thevertebra2 is open and the supply of bone substitute and/orbone reinforcing material3 to thevertebra2 is closed or that said supply of rinsing agent is interrupted and said supply of material open.
The rinsingagent7 may be of different types and it may e.g. be distilled water or a sodium chloride solution and/or be detergent and/or include at least one trombolytic substance, e.g. heparin, streptokinase, urokinase, TPA and/or other substances dissolving coagulum and thrombi.
The bone substitute and/orbone reinforcing material3 may consist of primarily minerals or ceramics which can be mixed with a hardener, e.g. water. These substances may be selected from the group comprising calcium sulphate-α-hemihydrate, calcium sulphate-β-hemihydrate, calcium sulphate-dihydrate, calcium carbonate, α-tricalcium phosphate, hydroxyapatite, dicalcium phosphate-dihydrate, anhydrous dicalcium phosphate, tetracalcium phosphate, β-tricalcium phosphate, calcium deficient hydroxyapatite, monocalcium phosphate-monohydrate, monocalcium phosphate, calcium-pyurophosphate, precipitated hydroxyapatite, carbonaceous apatite (dahlite), octacalcium phosphate, amorphous calcium phosphate, oxyapatite, carbonato apatite and calcium aluminate.
A ceramic material may be calcium aluminate, which forms part of the product Doxa T from the company Doxa (www.doxa.se/pdf/nyhet—1.pdf).
X-ray contrast agents can be added to said ceramic bone substitute and/orbone reinforcing material3, e.g. water soluble non-ionic X-ray contrast agents selected from the group comprising iohexol, ioversol, iopamidol, iotrolan, metrizamide, iodecimol, ioglucol, ioglucamide, ioglunide, iogulamide, iomeprol, iopentol, iopromide, iosarcol, iosimide, iotusal, ioxilan, iofrotal and iodecol.
Alternatively, the bone substitute and/orbone reinforcing material3 can be a hardenable bone cement comprising polymer and monomer components. The polymer may be polymethylmethacrylate (PMMA) and the monomer methylmethacrylate (MMA). A polymer base material can be the product Cortoss™ from the company Orthovita in the U.S. For composition see www.orthovita.com/products/cortoss/oustechspecs.html. Another polymer base material can be the product SECOUR® Acrylic Resin PMMA from parallax medical inc. (www.parallax-medical.com/go/9192b550-56421157-a432-d7a2b98310fe).
The bone substitute and/orbone reinforcing material3 may consist of a mineral and/or a ceramic in combination with polymer material.
The advantages with the invention is obvious when comparing the degree or ratio of fullness of thevertebra2 ofFIGS. 4 and 5. In thevertebra2 ofFIG. 4, the bone substitute and/orbone reinforcing material3 has been pressed into saidvertebra2 through a cannula or needle and it clearly appears fromFIG. 4 that only a part of thevertebra2 is filled with bone substitute and/orbone reinforcing material3. In thevertebra2 ofFIG. 5 however, the bone substitute and/orbone reinforcing material3 has been sucked into thevertebra2 in accordance with the invention through the cannula or needle and it is clearly evident fromFIG. 5 that substantially larger parts of thevertebra2 are filled with bone substitute and/orbone reinforcing material3 without said material having been pressed out into the blood paths.
It is also obvious fromFIG. 5 that the negative pressure generated by thevacuum source9 has provided for a uniform and complete distribution of the bone substitute and/orbone reinforcing material3 in thehole5 anddepressions5bin thesides5aof thehole5.
The invention is not limited to what is described above and illustrated in the drawings, but may vary within the scope of subsequent claims. Thus, thevacuum source9 may instead of aninjector pump21 be another vacuum pump which can be electrically operated or operated by gas or by hand or operated in any other way, that thehole5 may be more than one hole and surrounding parts thereto, that the rinsingagent7 may be another than those described and that the bone substitute and/orbone reinforcing material3 may be of another type than those described.
There may be a device for imparting pulse like suction and/or insertion movements to the bone substitute and/orbone reinforcing material3 into the hole(s)5 in thespongy bone1. Furthermore, there may be a device for imparting reciprocating suction and/or insertion movements to the bone substitute and/orbone reinforcing material3 into the hole(s)5 in thespongy bone1.
There may also be a device for pulse like suction and/or feeding of therinsing agent7 through the hole(s)5 in thespongy bone1.
Said device may be defined by pulsating thevacuum source9 and/or its vacuum generation and/or by generating pulses by means of thefeeding device30.
REFERENCE LIST- 1) Aebli Nt Krebs J, Schwenke D, Davis G, Theis J C. Cardiovascular charges during multiple vertebroplasty with and without vent-hole: an experimental study in sheep. Spine 2003;28(14):1504-11.
- 2) Koessler M J, Aebli N, pitto R P. Fat and Bone Marrow Embolism During Percutaneous Vertebroplasty. Anesth Analg 2003;97:293-294.
- 3) Lidgren, Lars. Bone Substitutes. Karger Gazette No. 65 2003; Bone and Joints.
- 4) Kirby B S, Doyle A, Gilula L A. Acute bronchospasm due to exposure to polymethacrylate vapours during percutaneous vertebroplasty. AJR J Roentgenol. 2003 Feb; 180 (2) :543-4.