LEAD ANCHOR FOR A NEUROMODULATION LEAD

Abstract

A lead anchor for neuromodulation includes a solid anchor block having at least one opening and a lumen. The opening is connected with the lumen and has a longitudinal axis. The lumen is configured to receive a portion of the neuromodulation lead. An anchor body at least partially covers the anchor block. A fixing element has a fastening portion and a head portion. To achieve a lead anchor that is more robust against axially acting forces, so that primarily a slippage of the lead or a slippage of the lead anchor can be prevented, the fastening portion is configured to be inserted along the axis into the opening to fix the portion of the neuromodulation lead. The head portion includes at least one first stop feature having a dimension in a radial direction with respect to the axis that is greater than a diameter of the opening.

Claims

1. A lead anchor (100) for a neuromodulation lead comprising: a solid anchor block (5) having a lumen (6) and at least one opening (9), wherein said lumen (6) is configured to receive a portion of the neuromodulation lead and wherein said opening (9) is connected with said lumen (6) and has a longitudinal axis (L1); an anchor body (4) at least partially covering said anchor block (5); and a fixing element (10) having a fastening portion (16) and a head portion (2), wherein said fastening portion (16) is configured to be inserted along the axis (L1) into said opening (9) to fix the portion of the neuromodulation lead, wherein said head portion (2) comprises at least one first stop feature (18) having a dimension (D4) in a radial direction (R1) with respect to said axis (L1) which is greater than a diameter (D1) of said opening (9).

2. The lead anchor (100) according to claim 1, wherein the head portion (2) comprises at least one second stop feature (17), wherein said stop feature (17) is configured to limit the movement of the fixing element (10) against the direction of insertion.

3. The lead anchor (100) according to claim 2, wherein the at least one first stop feature (18) and the at least one second stop feature (17) of the fixing element (10) are offset along the longitudinal extension of the fixing element (10) along the axis (L1).

4. The lead anchor (100) according to claim 1, wherein the portion of the neuromodulation lead is at least partially arranged within a sleeve (7).

5. The lead anchor (100) according to claim 4, wherein the sleeve (7) is permanently fixed within said lumen (6) of said anchor block (5).

6. The lead anchor (100) according to claim 4, wherein the anchor block (5) comprises at least one cap (15) arranged at one end of said lumen (6) and configured to secure the sleeve (7).

7. The lead anchor (100) according to claim 1, wherein the anchor block (5) comprises at least one eyelet (11) projecting from the anchor block (5).

8. The lead anchor (100) according to claim 7, wherein the at least one eyelet (11) protrudes from the anchor body (4) and penetrates the anchor body (4).

9. The lead anchor (100) according to claim 7, comprising at least two eyelets (11), wherein the eyelets (11) are arranged offset.

10. The lead anchor (100) according to claim 1, wherein the anchor block (5) comprises at least one projection (13), wherein sewing material is positionable at least partially around the at least one projection (13) when the lead anchor (100) is sutured.

11. The lead anchor (100) according to claim 1, wherein the anchor block (5) comprises one or both of a metal material or a polymer material.

12. The lead anchor (100) according to claim 1, wherein the anchor body (4) comprises polymer material.

13. The lead anchor (100) according to claim 1, wherein the head portion (2) of the fixing element (10) comprises a tool mount (1).

14. A method for manufacturing the lead anchor (100) according to claim 1, wherein the method comprises the following steps: providing the anchor block (5) with the at least one opening (9); inserting the fixing element (10) with its fastening portion (16) into the opening (9); and overmolding the anchor block (5), leaving at least the head portion (2) of the fixing element (10) partially exposed, thereby creating the anchor body (4).

Description

[0046] The various features and advantages of the present invention may be more readily understood with reference to the following detailed description and the embodiments shown in the drawings. Herein schematically and exemplarily,

[0047] FIG. 1 shows a top view of a lead anchor according to one embodiment of the invention,

[0048] FIG. 2 depicts a side view of the embodiment of FIG. 1,

[0049] FIG. 3A shows a longitudinal sectional view of the embodiment of FIG. 1, sectioned along the axis A of FIG. 1,

[0050] FIG. 3B shows a detailed view of the section B of FIG. 3A,

[0051] FIG. 3C depicts a detailed center section of FIG. 3A without the fixing element,

[0052] FIG. 4 shows a longitudinal sectional view of the anchor body of the embodiment of FIG. 1 and a corresponding view of the fixing element being separated, and

[0053] FIG. 5 shows a partially transparent view of a second embodiment of the lead anchor.

[0054] FIGS. 1 to 5 show a lead anchor 100 for a neuromodulation lead comprising an anchor block 5, an anchor body 4 and a fixing element 10, wherein the anchor body 4 covers or surrounds the anchor block 5. The fixing element 10 comprises a hexagon socket as a tool mount 1. As FIG. 1 shows a top view of the lead anchor, only a head portion 2 of the fixing element 10 is shown.

[0055] Further, two eyelets 11 are provided, wherein the eyelets are axially offset and wherein the eyelets 11 penetrate the anchor body 4. The eyelets 11 are integrally formed with the anchor block 5 and penetrate through the anchor body 4. FIG. 2 shows grooves 19 which may be used to guide the suturing material and thereby prevent axial slippage of the suturing material when the suturing material is fixed at the eyelets 11 during implantation of the lead anchor 100.

[0056] The axis marked with the arrows and letters ‘A’ represents the cutting axis for the longitudinal sectional views in FIGS. 3A and 3B. At the same time the axis extends along the longitudinal extension of the lead anchor 100. FIG. 3A shows that the anchor body 4 comprises a passage 20 which is formed as a cylindrical passage, extending along the cutting axis. The passage 20 is in line with a cylindrical lumen 6 of the anchor block 5 and thereby forming a lead-through for a neuromodulation lead. However, the lumen 6 as well as the passage 20 are best seen in the longitudinal sectional views of FIGS. 3A and 3B.

[0057] In FIG. 3A it is shown that the anchor block 5 is arranged within the anchor body 4 or the anchor body 4 covers the anchor block 5. Further, the anchor block 5 comprises a sleeve 7 and two press-fitted caps 15 securing said sleeve 7 at both longitudinal ends of lumen 6. Alternatively, those caps 15 may be fixed to the anchor block 5 in a different manner, for example by welding or by screwing. Sleeve 7 may be formed as a mesh.

[0058] Furthermore, the anchor block 5 comprises a cylindrical opening 9, wherein FIGS. 3A and 3B show that the fixing element 10 is already inserted within said opening 9 engaging said sleeve 7. The opening 9 is connected with the lumen 6 and extends perpendicular therefrom. The fixing element 10 comprises the head portion 2 with the tool mount 1 and a washer-like projection 3. The projection 3 forms a flange-like and ring-like lower surface 18 and a flange-like and ring-like upper surface 17, wherein the upper surface 17 is opposite the lower surface 18 (see FIG. 4). The projection 3 and herewith the upper surface 17 and the lower surface 18 have a fourth diameter D4.

[0059] The fastening portion 16 (see FIG. 4) extending along the shaft below the projection 8 may comprise a threaded portion, wherein the opening 9 also may provide a threaded portion at its inner surface in order to engage with the fastening portion 16 of the fixing element 10.

[0060] A first diameter D1 of the opening 9 of the anchor block 5 is shown in FIG. 4. Further, an arrow with arrowheads on both sides indicates the directions of movement of the fixing element 10 along axis L1, i.e. the direction of insertion and the direction against insertion. In addition, a contact surface 12 at a first end of the opening 9 is shown.

[0061] As the diameter D4 of the lower surface 18 of the fixing element 10 is greater than the diameter D1 of the opening 9, the lower surface 18 abuts to the contact surface 12 of the opening 9 when the fixing element 10 is inserted into the opening thereby limiting its movement into the direction of lumen 6.

[0062] As shown in FIG. 3C the anchor body 4 comprises an opening 41, as well, having a diameter D3 (see FIGS. 1 and 2). A widened portion of this opening 41 located just over the contact surface 12 of opening 9 of the anchor block 5, terminates in upper direction (i.e. away from the opening 9 and the lumen 6) with a flange-like and ring-like surface 42. As the diameter D4 of the upper surface 17 of the fixing element 10 is greater than the diameter D3, the upper surface 17 abuts to the flange-like surface 42 of the anchor body 4 when the fixing element 10 moves in a direction away from the lumen 6 thereby avoiding accidental removal of the fixing element 10.

[0063] Accordingly, the lower surface 18 forms the first stop feature according to the invention and the upper surface 17 forms the second stop feature which are provided by the same projection 3 but are offset along the longitudinal direction L1.

[0064] The second diameter D2 is the diameter of the fastening portion of the fixing element 10 which is slightly less than the first diameter D1 of opening 9.

[0065] Summarizing, the lead anchor 100 according to the first embodiment is formed by the anchor block 5 with the lumen 6 and the opening 9, and the eyelets 11 projecting from the anchor block 5. The opening 9 is provided with corresponding engagement means, so that the fixing element 10 can engage with the opening 9. If necessary, the sleeve 7 is provided within the lumen 6 of the anchor block 5, wherein the sleeve 7 may be welded into the anchor block 5, held by caps 15 or fixed in the anchor block 5 in some other way.

[0066] In FIG. 5 a lead anchor 100 of a second embodiment is shown in a top view, with the anchor body 4 being partially transparent, so that the anchor block 5 is visible inside the anchor body 4. Instead of eyelets, FIG. 5 has four rows of projections 13, wherein each two rows are located at the right and left end section of anchor block 5 in longitudinal direction. In total, the lead anchor 100 shows six projections 13 per side. The pin-like projections project perpendicularly from the outer surface of the anchor block 5 and protrude through the anchor body 4 so that they are accessible from the outside. Alternatively, one row of projections may be provided at each end section.

[0067] The lead anchor shown in FIG. 5 comprises four rings 14, one ring 14 per row of projections 13. Alternatively, there can be more or less projections 13 and correspondingly more or less rings 14. The projections 13 help a physician to suture the lead anchor 100 in the patient's body, for example in his or her fascia. The suturing material can be guided around the projections 13 in a suitable manner, so that the lead anchor 100 can be held in place. Further, the suturing material may be guided through the rings 14. Thus, the rings 14 may prevent the suturing material from slipping axially in the longitudinal direction of the lead anchor 100.

[0068] Even if no further embodiments are shown, the different components of the different embodiments of the present invention can of course be combined with each other as desired.

[0069] Hereinafter, during manufacturing of the lead anchor (for example a lead anchor 100 of the first embodiment) the anchor block 5 is provided and the fixing element 10 is inserted and screwed into the opening 9 along the longitudinal axis L1 until the first stop feature 18 abuts the contact surface 12 of the anchor block 5. It is then screwed back for a small distance such that it does not abut the contact surface 12 anymore. The anchor block 5 is then overmolded with a soft material such as silicone, leaving part of the head portion 2 of the fixing element 10 exposed by forming the opening 41 and the flange surface 42 of the anchor body 4. The overmolding material forms the anchor body 4 which comprises the passage 20.

[0070] With the fixing element 10 is partially loosened, i.e. its projection 3 having a short distance to the contact surface 12 of opening 9 of the anchor block 5 a neuromodulation lead (not shown) is passed through the lead anchor 100, i.e. through the lead-through formed by the lumen 6 and the passage 20. The fixing element 10 may then be used to fix the neuromodulation lead by screwing the fixing element 10 into the opening 9 using the tool mount 1 until the first stop feature (lower surface 18) of the fixing element 10 abuts the contact surface 12 of the anchor block 5, thereby limiting the movement of the fixing element 10 into the insertion direction, and thus limiting the force to be applied on the neuromodulation lead. The lead anchor 100 is then sutured into the patient body, wherein the suturing material is guided through the eyelets 11 and/or fixed with the help of the projections 13. In addition, the grooves 19 may be used to guide the suturing material.

[0071] The individual steps of a possible application of the lead anchor 100 described above should not be understood as limiting. Just as it may be possible that the fixing element 10 is inserted into the anchor block 5 after overmolding the anchor block 5, it is possible that the lead anchor 100 is first sutured into the patient's body and then the neuromodulation lead is guided through the lead anchor 100 and fixed in place with the fixing element 10.

REFERENCE NUMERALS

[0072] 1 Tool mount [0073] 2 Head portion of fixing element 10 [0074] 3 Projection [0075] 4 Anchor body [0076] 5 Anchor block [0077] 6 Lumen [0078] 7 Sleeve [0079] 9 Opening [0080] 10 Fixing element [0081] 11 Eyelet [0082] 12 Contact surface of the opening 9 [0083] 13 Projection [0084] 14 Ring [0085] 15 Cap [0086] 16 Fastening portion of fixing element 10 [0087] 17 upper surface (second stop feature) [0088] 18 lower surface (first stop feature) [0089] 19 Groove [0090] 20 Lead-through [0091] 100 Lead anchor [0092] D1 First diameter (of the opening) [0093] D2 Second diameter (of the fastening portion) [0094] D3 Third diameter (of the opening 41 of the anchor body 4) [0095] D4 Fourth diameter (of the projection 3) [0096] L1 Longitudinal axis [0097] R1 Radial direction