EP1868509A1

EP1868509A1 - Instrument for disimpacting a damaged vertebral body

Info

Publication number: EP1868509A1
Application number: EP06724317A
Authority: EP
Inventors: Claudio Lamartina; Dirk Weidmann; Mathias Heller
Original assignee: Zimmer GmbH
Current assignee: Zimmer GmbH
Priority date: 2005-04-14
Filing date: 2006-04-13
Publication date: 2007-12-26
Also published as: WO2006108661A1; EP1712185A1; US20090076515A1

Abstract

The invention relates to an instrument for disimpacting a damaged vertebral body, comprising a unit (11), whose effective length can be adjusted in a longitudinal direction and whose underside can be positioned on the skin (69) above a damaged vertebral body. According to the invention, supports (17, 19) that can be displaced in relation to one another are located on the adjustable unit, the distance between the exteriors of the two supports that face away from one another in the longitudinal direction defining the effective length of the adjustable unit. The adjustment range of the effective length is dimensioned in such a way that the supports can be positioned between lever elements (63, 67), which are provided for the distraction of the vertebral bodies lying cranially and caudally adjacent to the damaged vertebral body and the supports are designed to maintain the mutual distance between the lever elements.

Description

INSTRUMENT FOR ORIENTING A BROKEN ANGLE BODY

The invention relates to an instrument and a method for erecting a buried vertebral body.

A vertebral body fracture is a fracture of a vertebral body of the spine. Such a fracture may, for example, be the result of an accident (traumatic vertebral body fracture) or osteoporosis-related. Several methods are known from the prior art for rebuilding a broken-in vertebral body.

In vertebroplasty, the patient, who is lying on the abdomen, is inserted into the affected vertebral body via a percutaneous transpedicular cannulation under X-ray control. To erect and stabilize the vertebral body, bone cement is then injected via the cannula. In this method, however, the buried vertebral body is usually not completely erected. In vertebroplasty, it may further be found that greater pressure is required on the bone cement, and consequently the injected one

Bone cement can escape through the fractured surfaces or the venous blood vessel system again.

In kyphoplasty, the patient lying on the abdomen undergoes a x-ray control and uses a cannula to insert a balloon catheter into the affected vertebral body via a percutaneous transpedicular cannulation. To erect the vertebral body of the balloon catheter is inflated with an X-ray contrast liquid. After draining the contrast fluid, the balloon catheter is removed. In which of the balloon Catheter-left cavity is then injected via the cannula bone cement to stabilize the vertebral body. In this method, however, the broken-down vertebral body, to which the two adjacent vertebral bodies press, is usually also not completely erected. The balloon catheters required for kyphoplasty are also expensive.

In addition to vertebroplasty and kyphoplasty, so-called lordoplasty has recently become more popular. This is a method which is shown in FIG. 6 and in which in the cranial and caudally adjacent vertebral bodies 73, 77 of the vertebral body to be treated 75 lever elements 63, 67 - in this example cannulas - are inserted and in particular cemented, which are used as lever arms to relieve them before injecting bone cement into the broken vertebral body 75. As a result, the original vertebral body height and spinal curvature can be restored at least approximately. A balloon catheter is not necessary for this.

In the case of the lordoplasty, it can happen that the needles bend comparatively strongly when levered, ie when compressed relative to one another, so that often the desired lever effect can at least not be achieved completely. For example, the cannulas can already touch each other without the desired relief for the buried vertebral body is reached. In addition, in this process, the involved vertebral bodies are pressed together posteriorly and thus exposed there to an increased pressure, whereby bone pieces can be pressed into the nerve canal. Finally, the surgeon's hands holding the lever arms or cannulae are held and in position, loaded with high radiation doses, since the operation takes place at least partially under X-ray control.

It is an instrument and a method of the type mentioned are given, with which the methods described above can be improved

The instrument specified in claim 1, the instrument system specified in claim 18 as well as the method specified in claim 27 assets, in addition to a number of other advantageous properties, to meet this requirement.

In the case of the instrument specified here, a device-also referred to below as a spacer-is provided which is adjustable in its length in a longitudinal direction and can be positioned with its underside over a broken-in vertebral body on the skin. It is further provided that are arranged on the adjustable device relative to each other adjustable abutment, that the distance of the opposite outer sides of two abutments in the longitudinal direction defines the effective length of the adjustable device that the adjustment of the effective length is dimensioned such that the abutment between Lever elements are positioned, which are provided for the distraction of the fractured vertebral body cranially and caudally adjacent vertebrae, and that the abutment are designed to maintain the mutual distance of the lever elements.

The lever elements can be cannulas, for example biopsy needles. Therefore, the lever elements are also referred to below as cannulas, the stated properties and advantages Ie principle for any type of lever elements applies. The abutments can be arranged adjacent to the underside of the adjustable device. Furthermore, the abutments can protrude laterally from the adjustable device.

In order to ensure the length adjustability, the spacer may comprise in one embodiment a base member and an adjustable relative to the base member adjustment, wherein at least one abutment with the base member and at least one abutment is connected to the Ver adjusting element. The effective length of the spacer can be adapted to the mutual distance of the cannulas, in particular at the entry or exit points into and out of the skin. In particular, the spacer can fix a mutual minimum distance between the cannulas.

The abutments provided for fixing the mutual spacing of the cannulas are also referred to below as distance holding means.

The spacer means of the base member may be associated with both the cranial cannula and the caudal cannula. The spacer means of the adjustment is then assigned according to the cannula of the other direction.

The spacer means may protrude to the left and / or right, in particular symmetrically from a center plane of the spacer of the base member and the adjusting element.

For the base element and the adjusting element, in particular a distance-holding means can be provided in each case, which is designed as a continuous rod or the like and at the same time projects to the left and to the right. For the base element and the adjusting element, however, two or more distance-retaining means may also be provided, of which at least one distance-retaining means projects to the left and at least one distance-retaining means projects to the right. Spacer devices that protrude to the left and to the right are particularly suitable in cases where two lever elements, eg cannulas, are set for each adjacent vertebral body.

The adaptation to the mutual distance of the cannulas takes place in particular with non-actuated cannulas, i. before the cranial cannula and the caudal cannula are compressed relative to each other. The distance between the cannulas, in particular on the skin or in the vicinity of the skin which is present when the cannulas are not actuated, can also be maintained by the spacer, even when the cannulas are actuated, i. in a state where the cannulas are compressed relative to each other. In this way it can be prevented that the involved vertebral bodies are pressed against each other posteriorly and each exposed to an increased pressure.

The instrument system disclosed herein comprises an instrument of the type specified herein as well as lever members, e.g. Cannulas, which can be introduced into the vertebral body and are provided for the distraction of the vertebral body which is cranially and caudally adjacent to a broken-in vertebral body.

A method in which the instrument or instrument system specified here is used comprises introducing at least one device for introducing bone cement into the buried vertebral body and in each case at least one cranial and one caudal lever element in the cranially and caudally adjacent the fractured vertebral body Vortex bodies, the positioning of the instrument between the cranial lever element and the caudal lever element on the skin, whereby in the region of the abutment of the instrument, the mutual minimum distance of the lever elements is fixed, the compression of the lever elements relative to each other on the skin protruding areas, whereby a distraction of the cranial and causing caudal adjacent vertebral body and the buried vertebral body is relieved, and the introduction of bone cement into the buried vertebral body by the device for introducing bone cement.

It is possible, in the collapsed and the immediately adjacent vertebral bodies, two devices each for introducing bone cement or lever elements, e.g. Needles to bring.

Further embodiments are also specified in the dependent claims, the description and the drawing, wherein the features of these embodiments can be combined with each other in any desired manner.

It can be provided that the position of the adjusting element on the base element is aretrable.

The base element may have at least one longitudinally oriented longitudinal beam.

At least a portion of the base member may be formed in the manner of a frame having two side members arranged as side members. Due to the at least partial embodiment of the base element as a frame material and weight can be saved. In addition, can Space for the adjustment and / or the adjustment mechanism are created to allow a particularly compact design of the instrument.

In particular, elongated holes can be formed in the longitudinal members or side parts of the frame, in which the adjusting element is adjustably mounted. By the elongated holes, the storage of the adjusting element on the base element and at the same time the length adjustability of the adjusting element relative to the base element, in particular in a particularly simple manner, guaranteed. Through the slots can be additionally saved material and weight.

For setting different relative positions between the adjusting element and the base element, at least one of the slots may have a plurality of locking positions. As a result, the spacers adapted to the spacing of the cannulas, in particular at the entry points into the skin in its effective length, can be locked in the respective length. The locking positions may be formed in the form of circular arc-shaped depressions in the longitudinal sides of the slot. In such a depression, a cross-sectionally at least partially circular executed element of the adjusting element can be stored stationary and immovable.

Furthermore, it may be provided that the adjusting element comprises an adjusting part and an operating part connected to the adjusting part, which is switchable between a release position and a blocking position relative to the adjusting part, wherein in particular the adjusting part and the operating part are hinged together. In the release position of the control element, the spacer can be adjusted in its effective length along the adjusting device and then by transferring be locked in the blocking position with the set length. In an articulated connection between the adjusting part and the operating part, it is possible that when the operating part is switched over, the adjusting part can remain stationary in its position.

The operating part can protrude through a frame slot formed in a frame of the base element between longitudinal members. As a result, the operating part of the frame is bordered so to speak, so that a particularly compact design is possible.

The particular arcuate control panel can be rotationally rigidly connected to an axle mounted on the base element of the adjusting element. The switching movement of the operating part between a release position and a blocking position can thus be a rotary movement. Since the axis is rotationally rigidly connected to the control panel, both the axis mounted on the base member and the control panel is rotated in a switching movement of the control panel.

Furthermore, at least one abutment or distance-holding means can be formed on the adjusting part, wherein the adjusting part is articulated to an axis of the adjusting element mounted on the base element, which corresponds in particular to the axis rotationally rigidly connected to the operating part. During a rotary movement of the operating part and thus of the axle, the adjusting part can remain stationary in its position since the adjusting part is pivotally connected to the axle.

It is possible that the axis is adjustably mounted in oblong holes, in particular in oblong holes of side parts or side rails of a frame of the base member. The axis can be adjusted along the elongated holes. In addition, the axle allows at least a portion of the Adjustment, in particular the operating part, is rotatable relative to the base member. In particular, the axis can be flattened on two opposite sides, wherein it can be provided that the diameter of the axis substantially corresponds to the diameter of arcuate recesses in the longitudinal sides of a slot. In particular, by rotation, the flattened axis and thus the adjusting element can be fixedly locked to the base element and / or the lock can be released.

Furthermore, a stop element can be assigned to the abutment, which abutment is arranged adjacent to the upper side of the adjustable device, wherein the abutment elements in the longitudinal direction of the adjustable device at least in a locked position of an adjusting element of the adjustable device are arranged on the outside than the Abutment, such that the distance in the longitudinal direction between two abutments is smaller than that between two associated stop elements.

In particular, it can be provided that the base element has support means, which are arranged in particular at the same height as the support means of the adjustment. The support means are provided for supporting the patch on the spacer handle parts, especially when a fixing device for fixing the distance between the handle parts is not yet mounted.

The operating part may comprise at least one support leg which is arranged outside a frame of the base element and which serves as a stop element. The Abstützschenkel can be provided as a support point or support area for a handle part on the spacer can be placed and will be explained in more detail elsewhere. The grip part is also referred to below as a guide part.

The adjusting part can be adjustable along a recess of the base element, which extends on the underside thereof. This may be advantageous, since the adjusting element is provided with a distance-retaining means, which is thereby positionable close to the skin and can fix the distance of the cannula directly at the point of entry into the skin. In particular, this makes it possible for the adjusting part to form part of the support surface of the spacer holder on the skin.

In the case of the instrument system specified here, a handle part or guide part can be provided for a cranial and a caudal lever element, which can be placed on the adjustable device such that the guide part provides a contact surface for the respective lever element.

By compressing the guide parts or gripping parts relative to one another, the areas of the lever elements projecting out of the body, e.g. Cannulas, compressed relative to each other. Since the lever members can abut against the handle portions over a relatively large portion of their length, excessive bending of the portions of the lever members protruding from the body can be effectively prevented.

The guide parts can each be formed like a blade.

In order to provide the abutment surfaces, the gripping parts can each have a plate-like base section, which in particular slits centrally for placement on the spacer and / or for lateral guidance the lever element is provided with lateral abutment boundaries. The central slot allows the base section to also extend in the attached state of the grip part to the left and to the right of the spacer, so that a contact surface is available to the lever element over as large a portion as possible. The lateral restraints prevent the lever member from escaping to the left or right when levered to avoid the pressure of the handle portion or the base portion.

Furthermore, the handle parts may each have a particular S-shaped actuating portion, wherein in the mounted state, the actuating portions have a greater distance from one another than base portions of the handle parts. The handle parts can be actuated via the operating sections. To provide sufficient leverage and / or space for handles of the lever members, e.g. To provide cannulas, the distance of the actuating portions may be greater than the distance of the base portions.

According to one embodiment, the handle parts can be connected to one another via an adjustable fixing device, in particular an adjusting screw and / or a nut. By fixing the distance between the handle parts can be fixed in the attached state. This is especially true for an attached state in which the two handle parts are already compressed relative to each other. The surgeon is thus not forced, for example, to hold the actuated gripping parts or cannulas by hand during the injection of bone cement into the broken vertebral body by hand, so that the radiation exposure for the surgeon can be minimized. It is also possible that the fixing device not only for fixing the two handle parts, but in addition to the compression of the two handle parts relative to each other is used.

In order to enable a simple mounting of the fixing device, at least one grip part can have an insertion slot, through which the fixing device can be inserted into the grip part. As a result, the adjusting screw, in particular together with a nut, can be pivoted to a certain extent into this relative to the handle part. The insertion slot may be partially formed in a base portion and partially in an actuation portion of the handle portion, wherein the formed in the operating portion of the insertion slot may allow the passage of the nut.

The method set forth herein may include, after positioning the instrument on the skin and before compressing the lever members, translating the effective length of the instrument to the distance between a cranial and a caudal lever member at the exit site from the skin an adjusting element is adjusted relative to a base element, and that a loading part of the adjusting element is switched from a release position to a locked position relative to an adjusting part of the adjusting element.

Furthermore, the method may comprise - after the positioning of the instrument on the skin - a guide part between the bone cement introduction device and a stop element assigned to the abutment of the instrument being introduced cranially and caudally, and the guide parts are placed on the adjustable device of the instrument are placed such that in each case the guide part provides a contact surface for the lever element. Further, the method may include compressing the guide members relative to one another to compress the portions of the lever members protruding from the skin relative to each other.

Furthermore, the method may comprise - after the compression of the lever elements - the distance between the guide parts is fixed by means of an adjustable fixing device.

Furthermore, the method may include providing means for introducing bone cement as lever elements and - before compressing - bone cement is introduced into the immediately cranially and caudally adjacent vertebral bodies by the corresponding means for introducing bone cement.

The introduction of bone cement can be done by injection.

The invention will now be described by way of example with reference to the accompanying drawings. Show it:

1 is a perspective view of a spacer of an instrument specified here,

FIG. 2 shows perspective views of components of the spacer shown in FIG. 1 (adjustable device), FIG.

3 perspective views of handle parts (guide parts) of an instrument specified here, 4 shows different views of an instrument specified here with the spacer (adjustable device) of FIG. 1 and the grip parts (guide parts) of FIG. 3, FIG.

Fig. 5 shows a further embodiment of an instrument specified here, wherein additionally cannulas (lever elements) are shown, which are set in the broken and the immediately adjacent vertebral bodies, and

Fig. 6 is an illustration of a known from the prior art surgical procedure.

FIG. 1 shows a spacer 11 of an instrument or instrument system for erecting a buried vertebral body 75, which is shown in FIG. 6 only in connection with a surgical procedure known from the prior art. The spacer comprises a base element 13, which is additionally shown in Fig. 2a, and a multi-part adjusting element 15, the individual parts 29, 31, 39 are additionally shown in Figs. 2c to 2d. The adjusting element 15 is adjustable along an adjustment direction 71 on the base member 13 to the effective length between a rod-shaped spacer support shaft (abutment) 17 which is attached to a head portion of the base member 13, and a likewise rod-shaped spacer support shaft (abutment) 19, on the Adjustment element 15 is attached to adjust.

The spacer support shaft 17 and the spacer support shaft 19 each extend perpendicular to the adjustment direction 71 of the adjusting element 15 or to the longitudinal axis of the spacer 11, are each passed through a cylinder-shaped bore formed in the base member 13 and in the adjusting element 15 and are closed both sides, in particular symmetrically to a center plane of the spacer 11 from the base member 13 and the adjusting element 15 from.

The spacer 11 is provided between cannulas (lever members) 63, 67 shown only in connection with another embodiment of an instrument in FIG. 5 and in FIG. 6, on the skin 69 (FIG Operation is on the stomach, positionable. The cannulas 63 and 67 are set in the immediately adjacent vertebral bodies 73, 77 (FIG. 6) of the buried vertebral body 75. In FIGS. 5 and 6, in the adjacent vertebral bodies 73, 77 and in the buried vertebral body 75, two cannulas 63, 65, 67 are placed on the left and right of the plane of symmetry of the vertebral bodies 73, 75, 77. The effective length of the spacer 11 is adjusted such that the spacer support shafts 17, 19 abut the inside of the cannulas 63, 67 in order to fix the mutual distance of the cannulas 63, 67 at the entry points into the skin 69.

The base member 13 includes, in addition to the head portion, a portion formed like a frame 21. In the two side parts 23 of the frame 21 each have a slot 25 is formed, in which a flattened on two opposite sides of the axis 29 is adjustably mounted. Each of the two slots 25 has to set different relative positions between the adjusting element 15 and the base member 13 a plurality of locking positions, which are formed in the form of arcuate recesses 27 in the longitudinal sides of the slot 25.

The adjustment element 15 comprises an adjustment part 39 with a cylindrical bore, through which the distance support shaft 19 is inserted. In addition, the adjusting part 39 has a hinge section 79, the same if a cylindrical bore has and through which the axis 29 extends in the assembled state of the adjusting element 15 as shown in FIG. The adjusting part 39 and the axis 29 are hinged together, ie the axis 29 is freely rotatable within the cylinder bore of the joint portion 79 of the adjusting part 39. The adjusting part 39, in particular the section 79, on which the spacer support shaft 19 is formed, is adjustable along a recess 41 on the underside of the base member 13. The spacer 11 is thus on the fixed head portion and the adjustable adjustment part 39 on the skin.

The adjusting element 15 further comprises an operating part 31. The operating part 31 is arc-shaped and protrudes through a frame slot 33 formed in the frame 21 of the base element 13. The control panel 31 also includes a hinge portion 81 in which a bore for the axis 29 is formed and which is arranged in the assembled state of the adjusting element 15 of FIG. 1 adjacent to the hinge portion 79 of the adjustment member 39 and at this. The contour of the bore of the joint portion 81 of the base member 13 is adapted to the contour of the flattened axis 29, so that the operating part 31 is rotationally rigidly connected to the axis 29.

The operating part 31 is between a blocking position, in which the adjusting element 15 is locked in an undetachable manner to the base element 13 and which is shown in FIG. 1, and a release position in which the adjusting element 15 is adjustable along the adjustment direction 71 relative to the base element 13, switchable. In the locked position, the non-flattened sides of the axis 29 engage in the circular-arc-shaped depressions 27 in the longitudinal sides of the oblong holes 25 positively and non-positively, so that an adjustability along the adjustment direction 71 is effectively prevented. This is made possible in particular by the fact that the diameter the axis 29 substantially corresponds to the diameter of the circular-arc-shaped depressions 27 in the longitudinal sides of the elongated holes 25.

The release position is achieved in that the control unit 31 is pivoted about the axis 29, wherein due to the rigid connection between the operating part 31 and the axis 29 and the shaft 29 rotates. As a result, the non-flattened sides of the axis 29 and the recesses 27 in the longitudinal sides of the elongated holes 25 are disengaged, so that the adjusting element 15 can be adjusted in the adjustment direction 71 relative to the base element 13.

At its end, which projects upwards out of the frame slot 33 of the base element 13, the operating part 31 has a support leg 35 on both the left and the right, which extends laterally of the side parts 23 of the frame 21 outside the frame 21 of the base element 13 , At the Abstützschenkeln 35 each have a projection (stop member) 37 is formed, which is directed in the adjustment direction 71 and in analogy to a support shaft (stop member) 61 which is attached via a cylinder bore to the head portion of the base member 13 and symmetrically to the left and right of the spacer 11 projects, serves as a support means for handle parts (guide parts) 43, 45, which are shown in Fig. 3.

The grip parts 43, 45, each of which has the shape of a blade, can be placed on the spacer 11 in a cranial and caudal manner such that the grip parts 43, 45 provide a contact surface 47 for the cranial and caudal needles 63, 67. The handle parts 43, 45 each have a plate-like base portion 49 which is slotted centrally for placement on the spacer 11. In addition, the base portion 49 is provided with lateral abutments 51 for guiding the cannulas 63, 67 so that they can not escape to the left or right upon actuation of the handle parts 43, 45. Furthermore, the grip parts 43, 45 each have an actuating portion 53 which is designed in the shape of an S and connects directly to the base portions 49. In the state attached to the spacer 11 (FIG. 4), the actuating sections 53 are at a greater distance from each other than the base sections 49.

Finally, the instrument for erecting a broken-in vertebral body 75 comprises an adjustable fixing device 55, shown in FIG. 4, via which the two gripping parts 43, 45 are connected to one another in a state placed on the spacer 11. The fixing device 55 in this case comprises an adjusting screw 57 which is guided through or guided through a circular opening formed in the grip part 45 and an insertion slot 83 formed in the grip part 43, with a nut 59 on the end of the adjusting screw 57 emerging from the insertion slot 83 is screwed to fix the mutual position of the two handle parts 43, 45.

Another, second embodiment of an instrument for erecting a collapsed vertebral body 75 is shown in Fig. 5, wherein the same or corresponding parts are denoted by the same reference numerals, so that only the deviations of the second embodiment with respect to those shown in Figs first embodiment will be explained.

In the instrument according to FIG. 5, a support shaft 37, which projects to the left and to the right of the spacer 11, is attached to the upper end of the operating part 31. The support shaft 37 assumes the function of the projections 37 of the first embodiment. Finally, The second embodiment differs from the first embodiment in that the support means 61 assigned to the base element 13 are not arranged at the same height as the support means 37 associated with the adjustment element 15.

Hereinafter, a possible method for erecting a buried vertebral body will be described with reference to the figures.

First, in each case two cannulas 63, 65, 67 are placed in the buried vertebral body 75 and the immediately adjacent vertebral bodies 73, 77. Thereafter, bone cement is injected into the immediately adjacent vertebral bodies 73, 77. Once the bone cement injected into the adjacent vertebral bodies 73, 77 has cured, the surgical procedure can be continued. Of course, it is also possible that the provided for the broken vertebral body 75 needles 65 are set only after the injection of bone cement into the immediately adjacent vertebral bodies 73, 77 and / or the curing of the bone cement in the adjacent vertebral bodies 73, 77.

Next, the distance-adjustable spacer 11 is positioned on the skin 69 of a patient such that the mutual spacing of the cranial and caudal cannulas 63, 67 is fixed at the sites of entry into the skin. For this purpose, in the release position, the effective length of the spacer 11 is set such that the distance-holding shaft 17 and the distance-holding shaft 19 are in each case on the inner sides of the cranial or caudal cannulas 63, 67. If this is achieved, the control panel 31 is switched from the release position to the blocking position to lock the length of the spacer 11 at the appropriate distance. Of course, it is also possible that the setting of the cannulas 65 in the broken vertebral body 75, the injection of the Bone cement in the immediately adjacent vertebral bodies 73, 77 and / or the curing of the bone cement in the adjacent vertebral bodies 73, 77 during or after the positioning or the length adjustment of the spacer 11 is performed.

Subsequently, the two grip parts 43, 45 are inserted between the cranial and caudal cannulas 63, 67 and the spacer support shafts 17, 19 of the spacer 11 and placed on the spacer 11 such that the grip parts 43, 45 form a contact surface 47 for the cannulas 63, 67 provide. In the adjustment direction 71 - in each case from outside to inside - thus the following sequence is present (FIG. 5): support shaft 61 or 37 - grip part 43 or 45 - cannula 63 or 67 - distance support shaft 17 or 19.

Then, the gripping members 43, 45 are compressed relative to each other so that the portions of the cannulas 63, 67 protruding from the body of the patient are also compressed relative to each other. This ensures that the collapsed vertebral body 75 is relieved. The two distance holding shafts (abutments) 17 and 19 act as fulcrum or "break point" for the cranial and caudal needles 63, 67. The areas of the cannulas 63, 67 that are acted upon by the base sections 49 of the grip parts 43, 45 are not bent.

Once the desired distance between the handle parts 43, 45 is reached, which corresponds to a desired relief of the broken-in vertebral body 75, the distance between the handle parts 43, 45 is fixed by means of the fixing device 55. This is achieved in particular by tightening the nut 59 until it touches the grip part 43. In principle, it is also possible for the fixing device 55 to be used for compressing the two grip parts 43, 45 relative to one another per se. Finally, bone cement is injected into the buried vertebral body 75 via the cannulas 65 in order to stabilize the buried vertebral body 75. After hardening of the bone cement injected into the collapsed vertebral body 75, the instrument and the cannulas 63, 65, 67 set in the involved vertebral bodies 73, 75, 77 can be removed. The surgical procedure takes place at least partially under X-ray control.

The instrument specified here for erecting a broken

Vertebral body 75, which comprises at least the above-described spacer 11 and in particular also the two handle parts 43, 45 and the fixing device 55 explained above, makes it possible to improve all previously known surgical techniques described in connection with the prior art. In particular, a better supply of broken-in vertebral bodies can be ensured by the instrument or method specified here.

LIST OF REFERENCE NUMBERS

11 adjustable device, spacers

13 base element 15 adjusting element

17 abutment, distance holding shaft

19 abutment, distance holding shaft

21 frames

23 side panel 25 slot

27 deepening

29 flattened axis

31 control panel

33 Frame slot 35 Support leg

37 stop element, projection / support shaft

39 adjustment part

41 recess

43 guide part, handle part 45 guide part, handle part

47 contact surface

49 basic section

51 System limitation

53 operating section 55 fixing device

57 set screw

59 mother

61 Stop, support shaft

63 Lever element, cannula 65 Device for introducing bone cement, cannula

67 Lever element, cannula

69 skin

71 adjustment direction

73 vertebral bodies 75 fractured vertebral bodies to be erected

77 vertebral body

79 joint section

81 joint section

83 insertion slot

Claims

claims

An instrument for erecting a buried vertebral body (75) comprising a device (11) which is adjustable in a longitudinal direction in its effective length and which is positionable on the skin (69) with its underside over a buried vertebral body (75) adjustable means (11) relative to each other adjustable abutment (17, 19) are arranged, wherein the distance of the opposite outer sides of two

Abutment (17, 19) in the longitudinal direction of the effective length of the adjustable device (11) defined, wherein the adjustment range of the effective length is dimensioned such that the abutments (17, 19) between lever elements (63, 67) are positi- onable, are provided for the distraction of the fractured vertebral body (75) cranially and caudally adjacent vertebral bodies (73, 77), and wherein the abutments (17, 19) for maintaining the mutual distance of the lever elements (63, 67) are designed.

2. An instrument according to claim 1, characterized in that the abutments (17, 19) are arranged adjacent to the underside of the adjustable device (11).

3. Instrument according to claim 1 or 2, characterized in that the abutments (17, 19) protrude laterally from the adjustable device (11).

4. Instrument according to one of the preceding claims, characterized in that the adjustable device (11) has a base element (13) and an adjustable relative to the base element (13) adjusting element (15), wherein at least one abutment (17) with the base element

(13) and at least one abutment (19) is connected to the adjusting element (15).

5. Instrument according to claim 4, characterized in that it e e e n e c e s e s that the position of the adjusting element (15) on the base element (13) can be stored.

6. Instrument according to claim 4 or 5, characterized in that it e e n e c e s e s that the base element (13) has at least one longitudinally oriented longitudinal member (23).

7. Instrument according to one of claims 4 to 6, characterized in that at least a part (21) of the base element (13) is designed in the manner of a frame having two side members arranged as the longitudinal member (23).

8. Instrument according to claim 6 or 7, characterized in that in the longitudinal members (23) elongated holes (25) are formed, in which the adjusting element (15) is adjustably mounted.

9. Instrument according to claim 8, characterized in that at least one of the elongated holes (25) has a plurality of locking positions for setting different relative positions between the Ver adjusting element (15) and the base element (13), wherein in particular the locking positions in the form of circular arc-shaped recesses ( 27) are formed in the longitudinal sides of the slot (25).

10. Instrument according to one of claims 4 to 9, characterized in that the adjusting element (15) comprises an adjusting part (39) and a with the adjusting part (39) connected to the operating part (31), between a release position and a blocking position relative to the adjustment - Part (39) is switchable, wherein in particular the adjusting part (39) and the operating part (31) are hinged together.

11. Instrument according to claim 10, characterized in that the operating part (31) protrudes through a frame slot (33) formed in a frame (21) of the base element (13) between the longitudinal members (23).

12. Instrument according to claim 10 or 11, characterized in that the particular arcuate operating part (31) is rotationally rigidly connected to a base element (13) mounted on the axis (29) of the adjusting element (15).

13. Instrument according to one of claims 10 to 12, characterized in that on the adjusting part (39) at least one abutment (19) is formed, wherein the adjusting part (39) articulated with a base element (13) mounted on the axis (29) of Adjustment element (15) is connected.

14. Instrument according to claim 12 or 13, characterized in that the abplatte- in particular on two opposite sides axis (29) in slots (25) of the base member (13) is adjustably mounted, in particular the diameter of the axis (29) in Substantially corresponds to the diameter of circular-arc-shaped recesses (27) in the longitudinal sides of a slot (25).

15. Instrument according to one of the preceding claims, characterized in that on the adjustable device (11) each abutment (17, 19) is assigned a stop element (61, 37) which is arranged adjacent to the upper side of the adjustable device (11), wherein the stop members (61, 37) in the longitudinal direction of the adjustable

Device (11) at least in a locked position of an adjusting element (15) of the adjustable device (11) are arranged further out than the abutment (17, 19), such that the distance in the longitudinal direction between two abutments (17, 19) smaller is the one between two associated stop elements (61,

37).

16. Instrument according to one of claims 10 to 15, characterized in that the operating part (31) comprises at least one support leg (35) which is arranged outside a frame (21) of the base element (13) and serves as a stop element (39).

17. An instrument according to any one of claims 10 to 16, characterized in that e e n e c e s e s that the adjusting part (39) along a recess (41) of the base member (13) is adjustable, which extends on the underside thereof.

18. Instrument system comprising an instrument according to one of the preceding claims and lever elements (63, 67) in the vertebral body (73, 77) introduced and for distraction of a broken vertebral body (75) cranially and caudally adjacent vertebral bodies (73, 77) are.

19. Instrument system according to claim 18, characterized in that for a cranial and a caudal lever element (63, 67) in each case a guide part (43, 45) is provided, which is placed on the adjustable device (11) such that the guide part ( 43, 45) provides a bearing surface (47) for the respective lever element (63, 67).

20. The instrument system according to claim 19, characterized in that the guide parts (43, 45) are each formed like a blade.

21. Instrument system according to claim 19 or 20, characterized in that the guide parts (43, 45) each have a plate-like base section (49) which is centrally slotted in particular for placement on the adjustable device (11) and / or for lateral guidance of the lever element (63, 67) with lateral abutment boundaries (51 ) is provided.

22. Instrument system according to one of claims 19 to 21, characterized in that the guide parts (43, 45) each have a particular S-shaped actuating portion (53), wherein in the mounted state, the actuating portions (53) have a greater distance from one another Base portions (49) of the guide parts (43, 45).

23. Instrument system according to one of claims 19 to 22, characterized in that the guide parts (43, 45) can be connected to one another via an adjustable fixing device (55), in particular an adjusting screw (57) and / or a nut (59).

24. Instrument system according to claim 23, characterized in that at least one guide part (43) has an insertion slot (83) through which the fixing device (55) can be inserted into the guide part (43).

25. Instrument system according to one of claims 18 to 24, characterized in that the lever elements (63, 67) are also formed as means for introducing bone cement.

26. Instrument system according to claim 18, characterized in that the lever elements (63, 67) are designed as cannulas.

27. A method for erecting a buried vertebral body (75), comprising

Introducing at least one device (65) for introducing bone cement into the buried vertebral body (75) and in each case at least one cranial and one caudal lever element (63, 67) into the vertebral body (73, 77) immediately adjacent cranially and caudally to the buried vertebral body (75) ), Positioning an instrument according to any one of claims 1 to 17 between the cranial lever element and the caudal

Lever element (63, 67) on the skin (69), whereby in the region of the abutment (17, 19) of the instrument, the mutual minimum distance of the lever elements (63, 67) is fixed, compression of the lever elements (67, 69) relative zueinan- at protruding from the skin (69) areas, causing a distraction of the cranial and caudal adjacent vertebral body (73, 77) and the buried vertebral body (75) is relieved, and introduction of bone cement into the collapsed vertebral body (75) through the Device (65) for introducing bone cement.

28. The method of claim 27, comprising, after positioning the instrument on the skin (69) and before compressing the lever elements (63, 67), adjusting the effective length of the instrument to the distance between a cranial and a caudal lever element (63, 67) in the region of the exit point of the skin (69) by moving an adjusting element (15) relative to a base member (13), and

Switching an operating part (31) of the adjusting element (15) from a release position into a locked position relative to an adjusting part (39) of the adjusting element (15).

29. The method of claim 27 or 28, comprising, after positioning the instrument on the skin (69), insertion, cranial and caudal, each of a guide member (43, 45) between the means (65) for introducing bone cement and the Abutment (17, 19) of the instrument associated stop member (61, 37), and

Placing the guide parts (43, 45) on the adjustable device (11) of the instrument such that in each case the guide part (43, 45) provides a bearing surface (47) for the lever element (63, 67).

30. The method of claim 29, comprising

Compressing the guide members (43, 45) relative to each other to compress the portions of the lever members (63, 67) protruding from the skin (69) relative to each other.

31. The method according to claim 30, comprising after compression of the lever elements (63, 67),

Fixing the distance between the guide parts (43, 45) by means of an adjustable fixing device (55).

32. The method according to any one of claims 27 to 31, comprising

Provision of devices for introducing bone cement as lever elements (63, 67), and, prior to compression, introduction of bone cement into the directly cranially and cau- dally adjacent vertebral bodies (73, 77) by the corresponding

Means (63, 67) for introducing bone cement.

33. The method of claim 32, comprising introducing bone cement by injection.