TW201524452A - Polyaxial bone anchoring device with enlarged pivot angle - Google Patents

Abstract

A polyaxial bone anchoring device is provided comprising an anchoring element (1) having a shank (2) for anchoring in the bone and a head (3), the head having a spherically-shaped outer surface portion (3a); a receiving part (4) configured to be pivotably connected to the head (3), the receiving part (4) having a top end (4a) and a bottom end (4b), a central axis (C) extending through the top end and the bottom end, a transverse channel (52) for receiving a rod (100) and an accommodation space (44) for accommodating the head (3), the accommodation space (44) having a lower opening (45) at the bottom end (4b), a sleeve-like insert piece (5) having a sleeve axis (S) and configured to be positioned around a portion of the head (3) and to pivot in the receiving part (4), the insert piece (5) comprising a spherically-shaped outer surface portion; characterized in that the sleeve-like insert piece (5, 5') comprises at least a first part (510, 510') and a second part (520, 520') that are connected together through a guiding structure (51) that permits the first part (510, 510') to move relative to the second part (520, 520') only in a direction transverse to the sleeve axis (S).

Description

Multi-axis bone fixation device

The present invention relates to a multi-axis bone fixation device having an enlarged pivoting angle. The bone fixation device comprises a bone fixation element for fixation to the bone or vertebra; a receiving part for the bone fixation element to be coupled to the stabilization element, such as a spinal rod member, wherein the bone fixation element can be pivoted within the receptacle and can be pivoted The angle is pivoted outside of the central axis. Increasing the orientation of the pivoting angle can be selected within 360° of the central axis and can be automatically achieved by pivoting the receptacle relative to the bone fixation element. When the bone fixation element has been implanted into the bone, the receptacle can be mounted in situ to the bone fixation element.

A multi-axis bone fixation device is known from US 2012/0136395 A1, having an enlarged pivoting angle that can be selected within a range of 360° about the central axis. The multi-axis bone fixation device includes a sleeve-like insert that is positioned about a portion of the head of the bone fixation member and that is pivoted within the container. When the head, the insert and the pressure member are disposed in the accommodating member, the insert can be inclined with respect to the longitudinal axis of the accommodating member and with respect to the longitudinal axis of the fixing member, and the fixing member and the insert can press the head by the pressure member, and relative to The longitudinal axis of the receiving part is locked at an individual angle.

US 7,625,396 B2 describes a multi-axis bone screw assembly comprising a threaded stem body having an upper catching structure, a head and a multi-piece fastener joint structure. The head has a U-shaped cradle that defines a groove to accommodate the fixation or stabilization of the longitudinal connecting member. The geometric shape of the fastener structure is equivalent to the outer geometry of the catching structure, and can be cooperatively frictionally formed between the catching structure and the inner surface defining the head cavity to develop a fastener structure. The fastener structure includes a substantially spherical surface that cooperates with the inner surface of the head to provide a ball joint such that the head can be deployed at an angle relative to the stem body. Typically, the head and fastener structure can be assembled to the stem prior to implantation of the stem body into the vertebra.

It is an object of the present invention to provide an improved multi-axis bone fixation device having an enlarged pivoting angle that allows the bone fixation element to be inserted into the receiving member with a small force and is more flexible in use. Sex.

This purpose is solved by the multi-axis bone fixation device of the first application of the patent scope. Further developments are listed in the scope of the patent application.

The multi-axis bone fixation device is capable of mounting a receptacle that can be pre-assembled with a pressure member and a sleeve-like insert into a bone fixation member that has been inserted into a bone or vertebra. The "in situ" assembly of the multi-axis bone fixation device makes it easier for the surgeon to insert the bone fixation element into the bone, especially where special geometry or available space is reduced.

Because the multi-axis bone fixation device is a bottom-filled multi-axis bone fixation device, various possibilities are opened, and special bone fixation elements are combined with the accommodation members as needed before surgery. The bone fixation device delivered by the manufacturer can be pre-assembled with the pressure member and the sleeve-like insert, or with the dry portion of the screw. The multi-axis bone fixation device can be assembled at any location, by any person, especially a surgeon or any of its assistants, before or during surgery. Various cadres of different diameters, thread types, lengths or other characteristics can be combined with the accommodating parts in special clinical situations according to actual clinical needs. This allows the surgeon to physically select the implant and reduce the implant configuration.

With the modular type, the inventory maintenance cost can be reduced.

The sleeve-like insert provides an enlarged pivoting angle that is equal to or greater than 45° measured from a straight position. This makes the bone fixation device particularly suitable for lateral mass fixation, for example in the cervical spine. When the receiving member is pivoted relative to the bone fixation member, any orientation of the pivoting angle within 360° about the central axis can be adjusted by self-alignment of the sleeve-like insert.

Further features and advantages will be apparent from the description of the specific examples shown in the drawings.

1‧‧‧Fixed components

2‧‧‧ cadres

3‧‧‧ head

3a‧‧‧Spherical outer surface

4‧‧‧Accessories

4a‧‧‧Top of the holder

4b‧‧‧Bottom of the containment

5,5'‧‧‧Sleeve plug

5a‧‧‧Sleeve-like insert top

5b‧‧‧ sleeve-like insert lower edge

6‧‧‧ Pressure components

6a‧‧‧ Pressure member top

6b‧‧‧Bottom end of pressure member

8‧‧‧Bucking components

41‧‧‧ channel

44‧‧‧Inclusive space

44b‧‧‧Inclusive space base

45‧‧‧ opening

51,51'‧‧‧Guide structure

52‧‧‧Spherical inner surface

53‧‧‧Spherical outer surface

55‧‧‧ recess

56,56'‧‧‧ Pins

57,57'‧‧‧ recess

61‧‧‧The following face

64‧‧‧ recess

65‧‧‧ Groove

100‧‧‧ rods

510,510'‧‧‧ first component

520,520'‧‧‧ second component

510a, 510b, 520a, 520b‧‧‧ free end surface

C‧‧‧ center axis

S‧‧‧Sleeve axis

D ₀ ‧‧‧Maximum outer diameter

D ₁ ‧‧‧Maximum inner diameter

1 is an exploded perspective view of a multi-axis bone fixation device of a first specific example; FIG. 2 is a perspective view of a combined state of a multi-axis bone fixation device shown in FIG. 1; and FIG. 3 is a first and second diagram A top perspective view of the accommodating member of the multi-axis bone fixation device; Fig. 4 is a bottom perspective view of the accommodating member shown in Fig. 3; Fig. 5 is a plan view of the accommodating member shown in Figs. 3 and 4; 3 to 5 is a cross-sectional view of the accommodating member taken along line AA of Fig. 5; Fig. 7 is a perspective view of the pressure member of the multiaxial skeletal fixing device shown in Figs. 1 and 2. Figure 8 is a bottom perspective view of the pressure member shown in Figure 7; Figure 9 is a plan view of the pressure member shown in Figures 7 and 8; and Figure 10 is a pressure member shown in Figures 7 through 9 along the ninth Figure BB is a cross-sectional view; Figure 11 is an exploded top perspective view of the sleeve-like insert of the multi-axis bone fixation device shown in Figure 1; and Figure 12 is the first of the sleeve-like insert shown in Figure 11 a top perspective view of the assembly; Figure 13 is a bottom perspective view of the first component of the sleeve-like insert of Figures 11 and 12; and Figure 14 is a first component of the sleeve-like insert of Figures 11-13 Figure 15 is a cross-sectional view of the first component of the sleeve-like insert shown in Figures 11 through 14 along line DD of Figure 14; and Figure 16 is the second of the sleeve-like insert of Figures 1 and 11. a top perspective view of the assembly; Figure 17 is a bottom perspective view of the second component of the sleeve-like insert shown in Figure 16; and Figure 18 is a plan view of the second component of the sleeve-like insert shown in Figures 16 and 17; Figure 19 is a cross-sectional view of the second component of the sleeve-like insert of Figures 16 to 18 taken along line FF of Figure 18; and Figure 20 is a second embodiment of the sleeve-like insert of the multi-axis bone fixation device. An exploded perspective view; FIGS. 21 to 23 are cross-sectional views showing the assembly of the first embodiment of the multi-axis bone fixation device and the sleeve-like insert; and FIGS. 24 to 27 are the sleeve-like insert and the pressure member. A cross-sectional view of the pre-assembled accommodating member mounted to the bone fixation member inserted into the bone; Figure 28 is a detachment of the pre-assembled accommodating member with the pressure member and the sleeve-like insert to the inserted bone or vertebrae The final step sectional view of the component; Figure 29 is the pivotal position of the accommodating member together with the sleeve-like insert and the pressure member, and the inserted rod member relative to the bone fixation member implanted in the bone or vertebra. Figure.

As shown in Figures 1 and 2, the multi-axis bone fixation device of the first specific example comprises a bone fixation element 1 in the form of a skeletal screw having a threaded stem 2 and a head 3. The head 3 usually has a spherical outer surface portion 3a and a recess 3b at its free end, which can be combined with a screwdriver or a tool. head The portion 3 is formed to be held in the accommodating member 4, and the bone fixing member 1 is coupled to the stabilizer member 100. A sleeve-like insert 5 can be arranged in the receptacle 4, providing a head 3 of the bone fixation element 1 and a seat for the pressure member 6 pressed against the head 3. In addition, a fixing element, for example in the form of a fixing screw 7, can be provided, which secures the rod 100 in the receiving part 4, or in an opposing relationship.

The accommodating member 4 has a first end or a top end 4a and a second end or bottom end 4b, an axis C defining a central axis of the multi-axis bone fixture, and a coaxial bore 41 extending from the top end 4a in the direction of the bottom end 4b. Adjacent the top end 4a is provided with a substantially U-shaped recess 42 forming a groove to receive the rod 100. The two free portions are formed by the recesses 42, each having a female thread 43 for cooperation with the fixing screw 7.

Referring to Figures 3 to 6, the coaxial bore 41 opens into the containment space provided in the lower portion of the holder 4. The containment space 44 has a lower opening 45 at the bottom end 4b of the receptacle. Containment space 44 also contains a segment 44a, adjacent the coaxial bore 41, having a substantially hollow spherical sections, the inner diameter dimension D ₁ may allow a sleeve-like plug, the expansion by crossing the center axis C direction therein, and limit Its expansion. Further, the containment space 44 includes a second section 44b between the first section 44a and the lower opening 45 and also has the shape of a hollow spherical section having a maximum diameter at the upper end of the second section 44b. A third section 44c is provided adjacent the bottom end 4b and is substantially conically widened toward the bottom end 4b to provide a space for the stem 2 to pivot. The inner diameter of the coaxial bore 41 is smaller than the inner diameter of the first section 44a of the containment space, such that the upper end surface 46 of the containment space 44 has a seat or stop for the sleeve-like insert 5 to move toward the top end 4a. With the second section 44b of the containment space 44, the base of the sleeve-like insert 5 is provided such that the base and the sleeve-like insert 5 form a ball and socket joint. It should be noted that the base can also be tapered, or any other shape, which can be used to implement the ball and socket joint. The lower end of the second stage or the base 44b is oriented toward the bottom end 4b and has a smaller diameter than the maximum outer diameter D _{0 of the} sleeve-like insert, so that the sleeve-like insert 5 does not fall off through the lower opening 45 (see also Fig. 28).

It should also be noted that the coaxial bore 41, the inner diameter between the tip end 4a and the containment space 44, need not necessarily be constant. The coaxial bore 41 can have different locations of different diameters.

A transverse pin hole 47 extends from the outer surface of one of the strands into the coaxial bore 41. The pin hole 47 is for receiving the pin member 8, as shown in Fig. 1.

As seen in detail in Figures 7 through 10, the pressure member 6 is substantially cylindrical and has an outer diameter that permits movement within the coaxial bore 41 and containment space 44 of the receiver 4. The pressure member 6 has an upper end 6a and a lower edge 6b. Adjacent the lower edge 6b is provided with a spherical recess 61 which is spherically fitted to the spherical shape of the spherical outer surface portion 3a of the head 3.

The pressure member 6 has a cylindrical recess 62 at the upper end 6a to accommodate the rod 100. The pressure member 6 in turn has a coaxial bore 63 that allows the tool to access the head 3. The coaxial bore 63 also constitutes a portion of the allowable head 3 that extends through when the bone fixation element 1 is pivoted, as shown in FIG. The axial height of the pressure member 6 along the central axis C is such that when the set screw 7 is tightened, the set screw 7 is pressed against the rod 100 and pressed against the pressure member 6 to act on the head 3 of the bone fixation member 1.

The outer surface of the pressure member 6 disposed at the center of at least one of the portions of the cylindrical recess 62 is provided with an elongated recess 64 extending in the parallel direction of the central axis. The recess 64 does not completely penetrate the wall of the pressure member, so that an elongated groove is formed. The upper and lower short sides 64a, 64b of the recess 64 are rounded. The width of the elongate recess 64 in the direction transverse to the central axis C allows the recess 64 to receive and guide the front portion of the pin member 8, as shown in FIG. The pin member 8 can be a cylindrical pin that defines a pin hole 47 extending through the receiving member into the elongated recess 64. The function of the elongate recess 64, in maintaining the aligned position of the pressure member 6 relative to the accommodating member 4, aligns the recess 62 of the pressure member 6 with the recess 42 of the accommodating member to accommodate the rod member 100. Furthermore, when the pressure member 6 is inserted into the accommodating member 4, moving downward, the elongate recess 64 has a seat of the pin member 8 on its short upper side 64a. When the fixing member head 3 is inserted into the containing space 44 against the spherical recess 61 of the pressure member 6, and thus the pressing member 6 is pushed upward, the short lower side 64b serves as a stopper of the pin member 8, as shown in Fig. 26. .

The pressure member 6 is at a distance from the lower edge 6b and includes a groove 65 extending circumferentially. The depth of the groove 65 may be substantially the same depth as the elongated recess 64. The groove is at a height parallel to the central axis such that the groove 65 extends from the spherical recess 61 to the axial position of the cavity 63. The function of the groove 65 is to reduce the outer diameter of the pressure member. When the pressure member is inclined with respect to the longitudinal axis L of the bone fixing member 1 together with the pressure member 6 and the sleeve-like insert 5, as shown in Fig. 29, the sleeve can be made A portion of the insert 5 extends therein.

Referring to Fig. 11, the sleeve-like insert 5 is composed of two components, a left component or a first component 510, and a right component or a second component 520. Each component has an upper edge 5a and a lower edge 5b. The first component 510 and the second component 520 are connected by the connection structure 51 described below. The two components 510, 520 form a sleeve or a half of the ring with a sleeve axis S.

Referring to Figures 12-19, the first component 510 and the second component 520 each include a central interior 52 that is in the form of a hollow sphere having a radius corresponding to the radius of the spherical outer surface portion 3a of the head 3 of the bone fixation element 1. The outer surface 53 of the first component 510 and the second component 520 are spherical, so that when the first component 510 and the second component 520 are mounted together, the sleeve-like insert 5 has a spherical section The outer contour of the face. The outer surface 53 is sized and shaped to cooperate with the inner surface of the base 44b of the containment space 44 of the receptacle 4 such that the sleeve-like insert 5 is slidably and pivotally retained within the base 44b of the containment space. The center point of the spherical inner surface 52 and the spherical outer surface 53 is the same. However, the center point of the spherical inner surface portion 52 may deviate from the center point of the spherical outer surface portion 53 toward the lower edge 5b, further increasing the maximum pivoting angle.

When the sleeve-like insert 5 is placed in the base 44b such that its sleeve axis S is coaxial with the central axis C of the receiving member 4, the lower edge 5b protrudes beyond the lower opening 45 (see Fig. 28). When the sleeve-like insert 5 is pivoted or angled within the receiving member, such as shown in Fig. 29, at least a portion of the lower edge 5b still protrudes beyond the lower opening 45.

The lower edge of the central spherical portion 52 forms a shoulder 52a. The inner diameter of the shoulder portion 52a is smaller than the maximum outer diameter of the spherical head portion 3, so that the head portion 3 can be rotated and pivoted within the central spherical portion 52 of the sleeve-like insert 5, similar to a ball and socket joint. Between the shoulder 52a and the lower edge 5b, a beveled portion 54 is provided which tapers outwardly to allow the bone fixation element 1 to be angled until the stem 2 hits the lower edge 5b. The coaxial recess 55 extends from the upper edge 5a into the sleeve-like insert 5 to the central spherical interior 52. The inner diameter of the recess 55 is larger than the inner diameter of the central spherical portion, so that a space is provided for the lower portion of the pressure member 6. Therefore, the inner diameter of the cylindrical recess 55 is larger than the outer diameter of the lower portion of the pressure member 6. Further, when the cylindrical recess 55 is sized such that the bone fixing member 1 has a maximum pivoting angle with respect to the accommodating member 4, the pressure member does not block the sleeve-like insert, as shown in Fig. 29.

The first component 510 and the second component 520 each have two free end surfaces 510a, 510b, 520a, 520b extending in a plane containing the sleeve axis S. As shown in FIG. 11, the first free end surface 510a of the first component faces the first free end surface 520a of the second component 520, and the second free end surface 510b of the first component 510 faces the second of the second component 520. Free end surface 520b.

The respective end surfaces 510a, 510b of the first assembly, including the two male coupling members, are in the form of pins 56 spaced apart from each other in the vertical direction and projecting in the vertical direction of the sleeve axis S. The pin 56 is identical in shape and size. The opposing free end surfaces 520a, 520b, corresponding to the female coupling elements, form a recess or pin 57 that is positioned and shaped to match the position and shape of the pin 56 so that when the first component 510 and the second component 520 are mounted together At this time, the pin member 56 is coupled to the corresponding pin hole 57 to produce a buckle connection. The pin member 56 and the pin hole 57 are cylindrical, with the result that when the first member 510 and the second member 520 move relative to each other, they move in the traverse direction of the sleeve axis S. In addition, the pin member 56 contacts the inner wall of the pin hole 57 along the length of the pin member 56, inhibiting the tilting movement of the first component 510 relative to the second component 520. The two components 510, 520 move relative to one another, on the one hand, when the assembly is assembled to form the sleeve-like insert 5, limited by the free end surfaces 510a, 520a and 510b, 520b, and otherwise accommodated by the sleeve-like insert 5 The inner wall of the first section 44a of the space 44 is limited. The maximum inner diameter of the first section 44a of the containment space 44 is preferably slightly smaller than the maximum outer diameter _{D0 of the} sleeve-like insert plus the length of the pin member 56, so that the two components 510, 520 do not disengage within the containment space.

It should be noted that the two pins and the corresponding pin holes are only sufficient for each surface. It is also possible to conceive two or more pins. In addition, various modifications may be devised, such as having a first pin member in the first component 510, a pin hole in the second component 520, a second pin member in the second component 520, and a pin hole in the first component 510. .

Fig. 20 shows a specific example of the modification of the sleeve-like insert. The sleeve-like insert 5' differs from the sleeve-like insert 5 of the first specific example in the design of the connection structure 51'. All the same components and parts are given the same reference numerals, and the description thereof will be omitted.

The sleeve-like insert 5' includes a connecting structure 51', and the cylindrical pin-shaped male connecting member is changed into a rectangular-shaped pin member 56'. The second component 520' includes a unique pin member 56' at its free end surface 520a, 520b in a rectangular cross-section with the long side of the rectangle extending substantially parallel to the sleeve axis S. At the free end surfaces 510a, 510b of the first component 510', there are corresponding female coupling elements forming a recess sized and shaped to match the shape of the pin 56'. The recess 57' opens toward the outer surface 53.

It is contemplated that any connection structure is used to allow the two components 510, 520, 510', 520' to move apart while maintaining the two components oriented relative to each other.

The bone fixation device, whether integral or component, is made of a physiologically compatible material, such as a physiologically compatible metal such as titanium or stainless steel, a physiologically compatible alloy such as a NiTi alloy, such as Nitinol, or physiological compatibility. Plastic materials such as polyetheretherketone (PEEK), or physiologically compatible ceramic materials.

Referring to Figures 21-23, the assembly steps of the accommodating member, the sleeve-like insert and the pressure member will be described with respect to the first embodiment of the sleeve-like insert 5. When the sleeve-like insert 5' of the second specific example is used, the same steps are performed.

First, the two components 510, 520 are placed together such that the pin member 56 is coupled to the recess 57 and the free end surfaces 510a, 520a and 510b, 520b are engaged with one another to form a sleeve-like insert 5. Then, as shown in Fig. 21, the sleeve-like insert 5 is inclined by 90° and inserted into the accommodating member 4 at the position of the U-shaped recess 52. The sleeve-like insert 5 is moved downward toward the bottom end 4b of the holder 4. As shown in Fig. 22, when the sleeve-like insert 5 has sufficiently entered the containment space 44, i.e., it is tilted until its spherical outer surface 53 is seated in the base 44b of the containment space 44 (see Fig. 23), the sleeve-like insert 5 does not come out through the lower opening 45 because the inner diameter of the lowermost portion of the base 44b is smaller than the maximum outer diameter D _{0 of the} sleeve-like insert 5. The lower edge 5b projects outward from the bottom end 4b of the accommodating member 4. Further, as shown in Fig. 23, the pressure member 6 is inserted into the accommodating member 4 via the coaxial bore 51, so that the lower edge 6b extends into the cylindrical recess 55 of the sleeve-like insert 5. Thereafter, the pin member 8 is inserted into the transverse pin hole 47 of the receiving member so as to extend into the elongate recess 64 toward the front surface of the pressure member 6. When the pin member 8 abuts against the upper side 64a of the recess 64, the pressure member 6 is prevented from moving further downward. At the same time, the pressure member 6 is held by the pin member such that its cylindrical recess 62 is aligned with the U-shaped recess 42 of the accommodating member 4. In the case shown in Fig. 23, the sleeve-like insert 5 is axially movable relative to the accommodating member and is slidably pivoted within the base 44b.

See Figures 24 through 27 for the use of bone fixation devices. First, the bone fixation element 1 is inserted into a bone component or vertebra, such as a vertebrae, such that the head 3 extends beyond the bone surface 200, as shown in FIG. The accommodating member is pre-assembled with the sleeve-like insert 5, and the pressure member 6 is not yet mounted to the bone fixing member. Therefore, the bone fixation element is easier to insert, which is advantageous for situations where it is difficult to reach or where the available space is small. As also shown in Fig. 24, the accommodating member 4 is moved toward the bone fixing member using an instrument (not shown). Next, as shown in Fig. 25, by the downward movement of the accommodating member 4, the head portion 3 enters through the lower opening 45 of the accommodating member 4 until its spherical outer surface portion 3a hits the shoulder portion 52a of the sleeve-like insert 5. . The sleeve-like insert 5 is pushed in such a way that it leaves the base 44b and enters the first section 44a of the containment space, as indicated by the upright arrow below the bottom end 4b of the receptacle 4.

The sleeve-like insert 5 continues to move upwardly into the first section 44a of the containment space, with the head of the bone fixation element traversing the central axis C as indicated by the transverse arrow of Fig. 26, the sleeve-like insert 5 One assembly 510 and second assembly 520 are pushed away. The two components 510, 520 are moved apart, wherein the motion is limited by the inner wall of the first section 44a of the containment space. The movement is guided by the pin 56 and remains within the individual recesses 57. When the two components 510, 520 move apart from each other, the head 3 is allowed to enter between the two components 510, 520 until entering the cylindrical recess 55, against the spherical recess 61 of the pressure member 6, as also shown in Fig. 26. The bone fixation element 1 is inserted into the holder, requiring only a very light insertion force.

When the head 3 continues to press the spherical recess 61 of the pressure member 6, the pressure member 6 The first end 4a is moved upward relative to the receiving member 4 until the pin member 8 bears against the lower end 64b of the elongate recess 64. In this case, the pressure member 6 is prevented from coming out through the top end 49 of the accommodating member 4. As shown in Fig. 27, when the pressure member 6 and the head 3 are at the topmost position with respect to the accommodating member 4, the head portion 3 is no longer pressed against the two components 510, 520 of the sleeve-like insert 5, so that the two members 510, 520 can be mutually Moving in opposite directions and down until the sleeve-like insert 5 is again placed in the base 44b. During the downward movement, the two components 510, 520 are slidably guided by the connecting structure 51 realized by the pin 56 and the recess 57.

Finally, as shown in Fig. 28, the accommodating member is pulled up slightly so that the head 3 of the bone fixing member 1 is pulled into the base 52 of the sleeve-like insert 5. The pre-locking configuration here prevents the head 3 from being pulled out of the receiving part, since the head is fixed in the central spherical portion 52 of the sleeve-like insert 5, and the sleeve-like insert 5 is placed in the base 44b of the receiving part, Will fall off through the lower opening 45.

It should be noted that the pressure member 6 dimension, the elongated recess 64, and the pin member 8 position can be designed such that in the state shown in Fig. 28, the pressure member imparts a slight preload to the head 3, so that the head 3 is frictionally retained. Between the sleeve-like insert 5 and the pressure member 6. Thereby, the accommodating member can maintain the angular position with respect to the bone fixing member, and finally lock the angular position.

A plurality of bone fixation devices are implanted into the bone component or adjacent vertebrae, and the receiving member is tilted, as shown in Fig. 29, aligned with the groove to accommodate the stabilizer bar 100. The sleeve-like insert 5 is rotatable and pivotable within the holder 4, while the holder 4 and the sleeve-like insert 5 are rotatable and pivotable relative to the head of the bone fixation element 1. The sleeve-like insert 5 is directly received by the head in the bone retaining means in the receiving member 4, expanding the range of rotation angles because the insert 5 increases the stem of the bone fixation element 1 and the edge 5b of the lower opening 45 provides the distance between the supports.

As shown in Fig. 29, the stem 2 pushes the insert 5 until the stem 2 hits the wall of the third section 44c of the containment space 44. Therefore, in Fig. 29, the accommodating member 4 is pivoted with respect to the bone fixing member 1 at the maximum pivoting angle. The maximum pivoting angle that can be achieved depends on the dimensions of the sleeve-like insert 5, the receiving member 4 and the bone fixation element 1, but is generally equal to 45° measured from the straight or zero angular position between the receiving member 4 and the bone fixation element 1. the above.

Since the sleeve-like insert 5 can be rotated and pivoted within the accommodating member 4, an extended range of angles can be achieved at any position of the accommodating member 4 with respect to the bone fixing member 1 about 360 degrees from the central axis C of the accommodating member 4.

Although in the embodiment shown in Fig. 29, the pivoting is in the vertical plane of the axis of the member, it is to be understood that it can be carried out in any other direction within 360 degrees of the central axis C of the receiving member 4. Pivoted.

Finally, the rod 100 is inserted, the fixing screw 7 is tightened, the pressure member 6 is pressed to the head 3, and the head 3 and the sleeve-like insert 5 are locked.

It is to be noted that the bone fixation device can also be used to insert the accommodating member, the sleeve-like insert, the pressure member and the bone fixation member 1 into the bone after the pre-assembly of the accommodating member, the sleeve-like insert, the pressure member and the bone fixation member 1.

Further modifications are contemplated by way of specific examples. For example, for bone fixation elements, a variety of different fixation elements are available, combined with the holder. Such fixing elements may for example be screws of different lengths, screws of different diameters, sleeve screws, screws of different thread forms, nails, hooks and the like. For some fixing elements, the head and the stem can also be separate components that can be connected to each other.

Other possible modifications of the accommodating member may include, for example, changing a U-shaped recess perpendicular to the central axis to a lever recess that can be tilted toward the side opening, or forming a closed groove. There are other types of locking devices, including an outer nut, an outer nut, a screw-in locking device, and the like. In particular, a two-piece locking device can be used, comprising a first locking element, which is only pressed against the head by the pressure member, and a second locking element that only presses against the rod and locks the head and the rod, respectively. In some embodiments, the inner surface portion of the pressure member that is in contact with the head is not necessarily spherical. The inner surface portion may have any other shape suitable for pressing against the head.

The pin member that cooperates with the elongated recess provided by the pressure member can be replaced with other fastening mechanisms to keep the pressure member aligned with the receiving member and to prevent the pressure member from coming out through the top end of the receiving member. Two fastening members may also be provided, one on each side of the receiving groove.

Regarding the sleeve-shaped insert, a two-piece specific example is shown. However, it is also conceivable that two or more pieces are connected by a connecting structure to form a sleeve-like insert.

The head of the bone fixation element is symmetrical without rotation. For example, the head may have two opposing flat surface portions between the two spherical outer surface portions to achieve pivoting in only one plane.

2‧‧‧ cadres

3‧‧‧ head

4‧‧‧Accessories

4a‧‧‧Top of the holder

5‧‧‧Sleeve plug

5a‧‧‧Sleeve-like insert top

5b‧‧‧ sleeve-like insert lower edge

6‧‧‧ Pressure components

7‧‧‧ fixing screws

44a‧‧‧First section of inclusive space

54‧‧‧Beveling

55‧‧‧ recess

65‧‧‧ Groove

100‧‧‧ rods

C‧‧‧ center axis

L‧‧‧ longitudinal axis

Claims (18)

A multi-axis bone fixation device comprising: a fixing component (1) having a stem (2) for fixing in a bone, and a head (3) having a spherical outer surface portion (3a) a receiving member (4) is pivotally connected to the head (3), the receiving member (4) has a top end (4a) and a bottom end (4b), and a central axis (C) extends through The top end and the bottom end, a transverse groove (52) for accommodating a rod (100), and a containment space (44) for containing the head (3), the containment space (44) at the bottom The end (4b) has a lower opening (45); a sleeve-like insert (5) having a sleeve axis (S) formed around a portion of the head (3) and in the receiving member (4) Internally pivoted, the insert (5) includes a spherical outer surface portion (53); wherein the sleeve-like insert (5, 5') includes at least a first component (510, 510') and a second component (520, 520'), coupled together by a guiding structure (51), allowing the first component (510, 510') to traverse only one of the sleeve axes (S) relative to the second component (520, 520' ) athletes. A multi-axis bone fixation device according to claim 1, wherein the guiding structure (51, 51') comprises at least one convex element (56, 56') and at least one cooperative concave element (57, 57') The members are combined with each other and are in contact with each other along a length, so that the convex member is restrained from being inclined with respect to the concave member. A multi-axis bone fixation device according to claim 1 or 2, wherein the guiding structure (51, 51') comprises at least one pin member (56, 56') disposed in the first component (510, 510') Forming a recess (57, 57') extending into one of the second components (520, 520'). A multi-axis bone fixation device according to any one of claims 1 to 3, wherein the first component (510, 510') and the second component (520, 520') extend circumferentially around the sleeve axis (S) Each has two free end surfaces (510a, 510b; 520a, 520b) including the guiding structure (51, 51'). A multi-axis bone fixation device according to claim 4, wherein the sleeve-like insert (5, 5') has a maximum outer diameter (D ₀ ) when the two components are connected, such that the first component (510) The free end surface (510a, 510b) contacts the free end surface (520a, 520b) of the second component (520), and wherein the maximum diameter ( _D0 ) is greater than the interior of the containment space (44) The diameter below the base (44b). A multi-axis bone fixation device according to any one of claims 1 to 5, wherein the sleeve-like insert (5) has a spherical inner surface portion (52) forming a seat of the head (3). A multi-axis bone fixation device according to any one of claims 1 to 6, wherein a maximum inner diameter (D ₁ ) of one of the containment spaces (44) limits the first component and the second component (520, 520') Those who can move apart from each other. A multi-axis bone fixation device according to any one of claims 1 to 7 further includes a pressure member (6), the pressure member (6) being at least partially disposed in the containment space (44), The pressure member (6) includes a lower surface portion (61) configured to be in contact with the head portion (3), and when the head portion (3) and the pressure member (6) are disposed in the accommodating member (4), The head (3) is subjected to pressure. A multi-axis bone fixation device according to claim 8 wherein the sleeve-like insert (5, 5') has a top end (5a) and a bottom end (5b), and wherein the top end (5a) is provided There is a recess (55) sized to extend a portion (6b) of the pressure member (6) into the ejector. A multi-axis bone fixation device according to claim 8 or 9, wherein the pressure member (6) has a top end (6a) and a bottom end (6b), and a substantially cylindrical outer surface, and wherein At a distance from the bottom end (6b), a circumferential groove (65) is provided. A multi-axis bone fixation device according to any one of claims 8 to 10, wherein the pressure member (6) is formed in the accommodating member by a holding member (8), and the pressure member is restricted toward the accommodating member. (4) The top (4a) athlete. A multi-axis bone fixation device according to claim 11, wherein the fastening member (8) is a pin member extending from the receiving member into a recess (64) of the pressure member (6). A multi-axis bone fixation device according to any one of claims 1 to 12, wherein the sleeve-like insert is positioned in the receiving member (4) at a position such that the sleeve axis (S) and the central axis (C) When the shaft is coaxial, one of the lower edges (5b) of the sleeve-like insert (5, 5') extends through the lower opening (45). A multi-axis bone fixation device according to any one of claims 1 to 13, wherein the head (3) and the insert (5, 5') are disposed in the receiving member (4), the insert (5) , 5') can be inclined with respect to the central axis (C) of the receiving member (4), and wherein the fixing member (1) and the insert (5, 5') are pressed against the head (3) , can be locked at an individual angle relative to the central axis (C) of the receiving member (4). A multi-axis bone fixation device according to any one of claims 1 to 14, wherein the lower edge of the stem portion (2) of the fixing member (1) and the sleeve-like insert (5, 5') 5b) When not in contact, the sleeve-like insert (5, 5') and the fixing element (1) can be individually pivoted. A multi-axis bone fixation device according to any one of claims 1 to 15, wherein the stem portion (2) of the fixing member (1) is pivoted and combined with the sleeve-like insert (5, 5') When the lower edge (5b), Further pivoting of the fixing element (1) causes the sleeve-like insert (5, 5') to be pivoted together with the fixing element (1). A multi-axis bone fixation device according to any one of claims 1 to 16, wherein the receiving member has a passage (41) extending from the top end (4a) into the containment space (44), and wherein the passage (41) The inner diameter of the top end (4a) is smaller than the maximum outer diameter of the sleeve-like insert (5, 5'). A multi-axis bone fixation device according to any one of claims 6 to 17, wherein the spherical outer surface portion (53) and the spherical inner surface portion (52) of the sleeve-like insert (5, 5') have the same The center point.