WO2012140427A1

WO2012140427A1 - Implantable surgical cord anchor

Info

Publication number: WO2012140427A1
Application number: PCT/GB2012/050805
Authority: WO
Inventors: Jonathan Charles Lorrison; Bahaa Botros Seedhom; Alexander John HOGG; David John BEEVERS
Original assignee: Xiros Limited
Priority date: 2011-04-15
Filing date: 2012-04-12
Publication date: 2012-10-18
Also published as: GB201106434D0

Abstract

This invention relates to implantable cord anchorage devices for animals and humans and methods of manufacturing the same, optionally by using rapid manufacturing technology. One implantable surgical cord anchor (10) is disclosed which comprises: a main body (12) to be pressed or screwed into biological tissue; an internal cavity (14) extending internally along a region of the main body; an inner component (16) movable both axially and rotationally within the cavity of the main body such that the inner component may be inserted and withdrawn from the inner cavity via axial movement and rotated when inserted within the inner cavity; and cooperating locking components (18, 20) provided at an internal facing surface (22) of the inner cavity of the main body and an external facing surface (24) of the inner component such that the inner component is capable of being locked in position axially within the main body via engagement of the locking components.

Description

IMPLANTABLE SURGICAL CORD ANCHOR

The present invention relates to implantable cord anchorage devices for animals and humans and methods of manufacturing the same, optionally by using rapid manufacturing technology.

Numerous implantable devices are used in arthroscopic and orthopaedic surgery for use in repairing both soft and hard tissue injuries, particularly at joint regions. Examples include anchors for sutures or other surgical cords used to connect soft tissue to bone, including in particular securing tendons and ligaments whether these be of natural tissues or made from synthetic materials.

Anchorage devices for sutures, ligaments and tendons are typically required to be implanted into bone at a repair site so as to provide a means for attachment of soft biological tissue and/or a prosthetic. Such devices vary in their design both with respect to the portion that is configured to embed into the bone and the region that receives and anchors the soft tissue or synthetic cord.

Example suture anchors found in the art include US 7,713,286; US 7,695,495; US

7,674,276; US 7,651,528; US 7,588,587; US 7,517,357 and US 7,172,595. Typically, these relatively small implantable devices are manufactured using conventional processes that include, for example: traditional machining operations including milling, drilling, grinding, turning and broaching (that involves material removable from a solid block); casting followed by a suitable finishing process which typically involves machining; injection moulding; wire cutting or spark erosion. Whilst each of these different manufacturing processes has its own advantages when used to manufacture one or more different types of implantable device, they all have a common limitation. That is, such manufacturing processes can impose limitations on the geometry and complexity of the design features, particularly given the relatively small sizes involved and the requirement for

reproducibility to very small tolerances. The inventors have realised that improvements can be made to conventional implantable suture anchors and the like to enhance their performance when implanted. For example, features of the implantable surgical cord anchors of the subject invention that may be beneficial to both a physician during implantation and a patient post surgery include:

· external or internal features such as cavities with intricate and complex shapes and/or geometries that are configured to: i) secure the surgical cord, thread or tape to the suture anchor and/or: ii) to lock the anchorage device in position once implanted within hard or soft biological tissue. Such anchors are capable of providing anchorage of sutures and other artificial cords, tapes, textile tubes or sleeves or natural tissues including ligaments and tendons;

• entrapped components within internal cavities or chambers formed within the anchorage devices, such components being independently moveable and loose relative to the main implantable anchor or constrained to move within the cavities or chambers to i) lock the surgical cord (tapes, textile tubes or sleeves) at the anchor and/or to ii) lock the anchor in position at the hard or soft biological tissue site.

Such features enhance the functionality of the present implantable devices whilst facilitating implantation and patient recovery. It may be difficult to construct these features with conventional manufacturing processes associated with implantable devices such as bone anchors and the like.

According to a first aspect of the present invention there is provided an implantable surgical cord anchor comprising: a main body which can be pressed or screwed into biological tissue; an internal cavity or chamber extending internally along a region of the main body; an inner component movable both axially and rotationally within the cavity of the main body such that the inner component may be inserted and withdrawn from the inner cavity via axial movement and rotated when inserted within the inner cavity;

cooperating locking components provided at an internal facing surface of the inner cavity of the main body and an external facing surface of the inner component such that the inner component is capable of being locked in position axially within the main body via engagement of the locking components. At least part of the internal surface of the main body may taper or may be inclined relative to a longitudinal axis of the main body, and may be configured to cooperate with the external surface of the inner component. At least part of the external surface of the inner component may taper or may be inclined relative to a longitudinal axis of the inner component, and may be configured to cooperate with an internal surface of the main body.

At least part of the internal surface of the main body may taper or may be inclined relative to a longitudinal axis of the main body, and may be configured to cooperate with the external surface of the inner component, and at least part of the external surface of the inner component may be tapered or inclined relative to a longitudinal axis of the inner component. Said internal surface of the main body and external surface of the inner component may have corresponding tapers. A taper angle of said internal surface of the main body and said external surface of the inner component may therefore be the same.

Tapering the surface or surfaces may provide an enhanced engagement of a surgical cord coupled to the anchor. In particular, axial movement of the inner component relative to the main body may provide an enhanced clamping force on a surgical cord positioned between the surfaces.

Said tapered internal surface of the main body may be defined by a ramp, wedge or the like which extends into the internal cavity. Said tapered external surface of the inner component may be defined by a ramp, wedge or the like on the component. There may be a plurality of such ramps, wedges or the like on the main body/inner component.

A taper angle of said internal surface of the main body may be substantially constant in a direction along a length of the body, or may vary in a direction along the length of the body. A taper angle of said external surface of the inner component may be substantially constant in a direction along a length of the component, or may vary in a direction along the length of the component. The main body may define a proximal or upper opening through which the inner component can be inserted into the main body. Said internal surface of the main body may taper in a direction towards the proximal opening. This may provide an enhanced engagement of a surgical cord positioned between said internal surface of the main body and said external surface of the inner component. This is because, in use, an axially directed force may be exerted on the inner component (such as by the surgical cord), which may urge the inner component towards said proximal opening of the main body, thus enhancing a clamping force on a cord positioned between said surfaces. Said tapered internal surface may describe a dimension (such as a width) of the internal chamber of the main body, which dimension decreases in a direction towards the opening. Said internal surface may alternatively taper in a direction away from the proximal opening.

The inner component may have a proximal or upper end and may taper in a direction towards said end. Said tapered external surface may describe an external dimension (such as a width) of the inner component, which dimension decreases in a direction towards the end. Said external surface may alternatively taper in a direction away from the proximal end.

Reference is made herein to proximal and/or distal ends of the main body and the inner component. It will be understood that such references are made relative to a direction of insertion of the anchor into tissue, a distal end of the main body being the end which is inserted into tissue.

A space may be defined between said internal surface of the main body and said external surface of the inner component, which space may be shaped to receive a surgical cord. The main body and the inner component may be arranged (e.g. by appropriate

dimensioning) to exert a compressive clamping force on a surgical cord located in said space, when the inner component is located in the inner cavity of the main body. Said internal surface of the main body may be curved, and may curve in a direction around a perimeter of the body (e.g. around a circumference, where the body is generally circular in cross-section). This may be of particular use for clamping a surgical cord having a round or elliptical shape in cross-section. Said internal surface of the main body may be generally concave in the direction around the body perimeter. Said outer surface of the inner component may be curved, and may curve in a direction around a perimeter of the component (e.g. around a circumference, where the component is generally circular in cross-section). Said external surface of the inner component may be generally convex in the direction around the component perimeter. The space defined between said surfaces may have a non-constant width, which may be a radial width.

At least part of said internal surface of the main body may be planar (non-curved). At least part of said external surface of the inner component may be planar. The space may be defined between said parts of the main body internal surface and inner component external surface. Said space between the surfaces may have a constant width. This may be of particular use for clamping a surgical cord having a constant width (or a portion of a constant width), such as may be the case where the surgical cord (or portion thereof) is rectangular in cross-section, having flat opposed surfaces which can abut said surfaces of the main body and inner component.

One of the locking components may be a groove, channel or recess formed in or on one of the internal surface of the main body and the external surface of the inner component. The other one of the locking components may be a protrusion formed in or on the other one of the internal surface of the main body and the external surface of the inner component, and which can be located in the groove for locking the inner component against axial movement relative to the main body. The protrusion may be a key, dog, finger or flange.

There may be a plurality of locking components at the internal surface of the main body and the external surface of the inner component.

The groove may comprise an axially extending portion along which the locking protrusion travels during insertion of the inner component into the cavity, and a locking portion which extends transversely to the axial portion. The locking protrusion may prevent the inner component from axial movement relative to the main body when located in the locking portion of the groove. Axial movement at least in a direction towards the proximal opening of the main body may be restricted. The groove may comprise or may define a detent for the locking protrusion, which may restrain the inner component against axial and optionally also rotational movement relative to the main body. The detent may

communicate with the locking portion of the groove, and may restrict both rotational motion of the inner component relative to the main body, and axial movement of the inner component in a direction towards the proximal opening of the main body. This may prevent inadvertent release of the inner component from the main body. The detent may be a pocket in the locking portion of the channel, which pocket may extend in an axial direction towards the proximal end of the main body. At least one upset may be provided in the groove or at an entrance to the groove, which upset may define a restriction to passage of the locking protrusion. The locking protrusion or the upset may be deformable, so that it can be deflected to allow the locking protrusion to pass the upset. This may serve for retaining the locking protrusion in the groove, and so may resist separation of the main body and the inner component. The upset may be a lip, rib, ledge or finger, and may have a rounded profile or rounded edges to facilitate passage of the locking protrusion. There may be a first upset at an entrance to the groove, and a further upset positioned in the groove, which may be in the transverse locking portion of the groove, or at a junction between the axial portion and locking portion of the groove. The inner component may comprise means to receive a surgical cord such that the surgical cord may be looped or hooked around a portion of the inner component. The inner component may comprise an aperture extending through the inner component, which aperture can receive the surgical cord. The main body may be elongate.

According to a second aspect of the present invention there is provided an implantable surgical cord anchor comprising: a main body to be pressed or screwed into biological tissue; an internal cavity formed within the main body; a first and second aperture provided through the main body and into the internal cavity, the first and second apertures being positioned substantially on opposite sides of the main body; a bar or bridging member extending across the main body substantially perpendicular to a longitudinal axis of the anchor.

According to a third aspect of the present invention there is provided an implantable surgical cord anchor comprising: an elongate main body to be pressed or screwed into biological tissue; a moveable inner component accommodated at least partially within the main body and configured to move axially relative to the elongate main body; screw threads provided on an inner region of the main body and an outer region of the inner component, the inner component being moveable relative to the main body via cooperation between the screw threads; the inner component comprising means to receive a surgical cord such that the surgical cord may be looped or hooked around a portion of the inner component.

According to a fourth aspect of the present invention there is provided an implantable surgical cord anchor comprising: an elongate main body to be pressed or screwed into biological tissue; a moveable inner component accommodated at least partially within the main body and configured to move axially relative to the elongate main body; the main body having a tapered inner surface relative to its longitudinal axis configured to mate with a tapered outer surface of the inner component relative to the longitudinal axis of the main body; the inner component comprising means to receive a surgical cord such that the surgical cord may be looped or hooked around a portion of the inner component.

According to a fifth aspect of the present invention there is provided an implantable surgical cord anchor comprising: an elongate main body to be pressed or screwed into biological tissue; at least one barb moveably attached to the main body and configured to move radially outward from the elongate main body so as to present a radial extension projecting from an outer surface of the elongate main body to inhibit withdrawal of the anchor once implanted into the biological tissue. Optionally, the at least one barb is pivotally mounted at the elongate main body. Preferably, the elongate main body comprises an internal cavity or chamber and the anchor further comprises an inner component axially and/or radially movable within the internal cavity of the main body, the inner component configured to abut a region of the at least one barb so as to displace the barb radially outward from the elongate main body as the inner component is moved axially and/or radially within the internal cavity of the anchor.

According to a sixth aspect of the present invention there is provided an implantable surgical cord anchor comprising: an elongate main body to be pressed or screwed into biological tissue; external screw threads formed over an external facing surface of the elongate main body, the elongate body being pointed at one end and comprising an external taper from the pointed end to a second end; and an eyelet or hook configured to receive and attach to surgical cord, the eyelet or hook formed integrally with the elongate main body.

According to a seventh aspect of the present invention there is provided an array of implantable surgical cord anchors, each anchor comprising: an elongate main body to be pressed or screwed into biological tissue; external screw threads formed over an external facing surface of the elongate main body, the elongate body being pointed at one end and comprising an external taper from the pointed end to a second end; and an eyelet or hook configured to receive and attach to surgical cord, the eyelet or hook formed integrally with the elongate main body; each of the anchors being connected together via a surgical cord formed as an endless or knotless loop threaded through each of the eyelets or hooks of each anchor. Preferably, the endless loop is manufactured from a single piece of yarn looped together such that the ends of the yarn are accommodated within the looped structure so as to be embedded in the looped structure.

The implantable surgical cord anchor or anchors of the first to seventh aspects of the invention may be created by rapid manufacturing. The present invention may therefore provide implantable devices (surgical cord anchors) for a human or animal produced with rapid manufacturing processes. The rapid manufacturing processes may include: three- dimensional printing, stereolithography, selective laser sintering, shape deposition manufacturing, direct metal laser sintering (DMLS), laminated object manufacturing and injection moulding. These manufacturing processes may be advantageous not only for producing the final product, but also for the optimising of individual designs. The optimisation may be facilitated as the manufacturing processes may allow iterations of different device designs and sizes to be simultaneously produced in multiple numbers, thus expediting the process of testing and validating the performance in adequate numbers of each design, then choosing the optimal design. Accordingly, this may greatly reduce the time and cost of development of such devices. Other manufacturing methods or techniques may be employed where appropriate, including but not limited to casting (such as lost-wax casting) and machining, or indeed other methods such as those mentioned elsewhere in this document.

Further features of the anchors of any one of the first to seventh aspects of the invention may be derived from or in relation to one or more of the other aspects.

According to an eighth aspect of the present invention there is provided a method of manufacturing an implantable surgical cord anchor for a human or animal by rapid manufacturing.

According to a ninth aspect of the present invention there is provided a method of implanting an implantable surgical cord anchor within a human or animal, the anchor being manufactured by rapid manufacturing. According to a tenth aspect of the present invention there is provided an implantable surgical cord anchor obtained directly from a rapid manufacturing process.

Suitable materials of the present implantable anchorage devices (surgical cord anchors) include: metals; metal alloys, plastics including natural and synthetic polymers, resorbable and non-resorbable materials all being medical grade materials. In particular, the materials from which the present devices can be manufactured include titanium or cobalt chromium alloys, and Poly-Ether-Ether-Ketone or 'PEEK'.

The anchors of the present invention may be categorised into two generic types: single component devices and devices comprising multiple components some of which are moveable. Single component anchorage devices include bodies having a cavity with an opening or a substantially sealed internal chamber where the bodies are unitary and are not coupled, fused or held together as would be the case with assembled pre-moulded components. Such devices may comprise a protrusion extending within the cavity or substantially closed internal chamber. Such a protrusion may include a bar, flange, notch, hook or loop extending partially or an entire distance across the cavity or chamber. The open cavity or chamber may comprise a cannula or non-cannula geometry. The devices may comprise multiple or single cavities and chambers within which are positioned multiple or single protrusions or obstructions.

The second category of device comprises components that may be moved relative to one another, via for example, a manipulation or coupling joint connecting two or more single components. Such a joint may include a ball, universal, hinge, pivot, saddle, an ellipsoid or ratchet joint. Additionally, relative movement of the components may be achieved via sliding rods, male and female slip joints or other configurations in which a first member is configured to slide, relative to a second member.

The devices of the subject invention including single component devices and devices with multiple moveable components may be capable of being manufactured such that the main bodies of the devices and any movable components are formed from the same material simultaneously. This may be achievable by employing a rapid manufacturing process. The devices may not be constructed according to a sequential or step-by-step assembly procedure in which components are bonded or fused together as with conventional anchor devices.

According to an eleventh aspect of the present invention there is provided a medical and/or biological cord anchorage kit comprising: at least one cord anchor as described herein and a drive tool to drive the anchor into a biological anchorage site. Optionally the kit further comprises at least one medical cord or tape as described herein, including specifically a suture. Optionally, the cord or tape is pre-loaded and secured/locked to the anchor as part of the kit. Alternatively the cord may be unattached to the anchor within the kit.

According to a twelfth aspect of the present invention there is provided at least one or a plurality of drive instruments for driving and embedding the anchors at an intended biological site. These instruments may be manufactured with rapid processing technology. In particular, the ends of the instruments may be tailored with geometries to conform with and/or to fit snugly into the ends of the anchors. The drive tool is configured to extend away from the anchor with one end furthest from the anchor engaging end configured to mate with a suitably designed handle that may be gripped while introducing the anchor into the fixation site.

The driving instrument may comprise at least one hollow region to pass the medical cord (sutures or tapes) through the instrument at its end that is introduced into or mated with the anchor. According to this embodiment, the sutures or tapes would emerge through a side of the driving instrument at a distance from its end within or mated with the anchor.

In a further aspect or aspects of the present invention, there may be provided implantable surgical cord anchors having one or more of the features of the anchors of the first to seventh aspects of the invention defined above.

Embodiments of the present invention of the present invention will now described, by way of example only, and with reference to the accompanying drawings, in which:

figure 1 is a longitudinal cross-sectional view of a surgical cord anchor according to an embodiment of the present invention;

figure 2 is a perspective view of a main body forming part of the anchor shown in figure 1 ;

figure 3 is a longitudinal cross-sectional view of the main body of the anchor shown in the same orientation as figure 1 ;

figure 4 is a longitudinal cross-sectional view of the main body of the anchor viewed in a direction which is perpendicular to that shown in figure 3;

figure 5 is an enlarged plan view of the main body of the anchor; figure 6 is a perspective view of an inner component forming part of the anchor shown in figure 1 ;

figure 7 is a front view of the inner component of the anchor shown in the same orientation as figure 1 ;

figure 8 is a side view of the inner component of the anchor;

figure 9 is an enlarged plan view of the inner component of the anchor;

figure 10 is a longitudinal cross-sectional view of a main body forming part of a surgical cord anchor according to another embodiment of the present invention;

figure 11 is a perspective view of a surgical cord anchor according to another embodiment of the present invention;

figure 12 is a partial longitudinal cross-sectional view of the surgical cord anchor of figure 11 , taken in the direction of the arrows A-A;

figure 13 is a perspective view of a main body forming part of the anchor shown in figure 11 , illustrated in the same orientation;

figure 14 is a perspective view of an inner component forming part of the anchor shown in figure 11 , illustrated in the same orientation;

figure 15 is a side elevation view of a fixation anchor according to a specific implementation of the present invention;

figure 16 is a plan view of the fixation anchor of figure 15;

figure 17 is a cross-sectional side elevation view through B-B of the fixation anchor of figure 16;

figure 18 is a further embodiment of a fixation anchor that accommodates a bone screw according to a specific implementation of the present invention;

figure 19 is a cross sectional side elevation view of the anchor of figure 18 accommodating a bone screw;

figure 20a illustrates the fixation anchor of figure 19, anchored in position at a bone and providing anchorage for a ligament according to a first embodiment;

figure 20b illustrates the fixation anchor of figure 20a providing anchorage for a ligament according to a second embodiment;

figure 21 a is a perspective view of a surgical cord anchor according to a further embodiment of the present invention; figure 21b is a perspective view of the housing component of the cord anchor of figure 21a;

figure 21c is a perspective view of a core insert of the implantable cord anchor of figure 2 la;

figure 22a is an external side elevation view of an implantable cord anchor according to a further embodiment;

figure 22b is a cross sectional side elevation view of the implantable cord anchor according to figure 22a;

figure 23 is a cross sectional side elevation view of a further embodiment of an implantable cord anchor;

figure 24a is a side elevation view of the anchor of figure 24a with an insert housed within an outer housing;

figure 24b is a perspective view of the implantable anchor of figure 24a;

figure 25 is a perspective view of a further embodiment of the implantable surgical cord anchor; with an external body shown in the lower drawing and an internal, core shown in the upper drawing;

figure 26 is a cross sectional side elevation view of the anchor of figure 25;

figure 27 is a perspective view of the anchor of figure 25 with an insert accommodated within an outer housing;

figure 28 illustrates the anchor of figure 27 with the insert rotated within the housing to a locked position;

figure 29 is a perspective view of a medical cord anchorage device according to a further specific embodiment;

figure 30 is a cross sectional side elevation view of the anchor of figure 29;

figure 31 is a perspective view of the anchor of figure 30 in which an insert is accommodated within an outer housing;

figure 32 is a cross sectional side elevation view of a further embodiment of a medical cord anchor;

figure 33 is a side elevation view of the anchor of figure 32 having been rotated through 90°;

figure 34 is a perspective view of a removable insert component of the anchor of figure 33; figure 35a is a perspective view of an insert of an implantable medical cord anchor according to a further embodiment;

figure 35b is a cross section perspective view of an outer housing for the insert of figure 35a;

figure 35c is a plan view of the insert of the housing of figures 35a and figure 35b; figure 35d is a perspective view of the insert of figure 35a accommodated within the housing of figure 35b according to the further embodiment;

figure 36 is a cross sectional side elevation view of an implantable medical cord anchor according to a further specific embodiment;

figure 37 is an end view of the device of figure 36;

figure 38 is a side elevation view of an implantable medical cord anchor according to a further specific embodiment;

figure 39 is a side elevation of a side elevation view of a further embodiment of the insert of figure 38;

figure 40 is a cross sectional side elevation view of a medical cord anchor according to a further embodiment;

figure 41 is an end view of the anchor of figure 40;

figure 42 is a side elevation view of an end section of the anchor of figure 40; figure 43 illustrates a side elevation view of an end section of a medical cord anchor according to a further embodiment;

figure 44 illustrates an end view of the anchor of figure 43;

figure 45 is a perspective view of the anchor of figure 43;

figure 46 is a cross section perspective view of a surgical cord anchor according to a further embodiment;

figure 47 is a cross sectional side elevation view of the anchor of figure 46with an insert located external to an outer housing component;

figure 48 is an external perspective view of the anchor of figure 46;

figure 49 illustrates multiple views of further embodiments of a medical cord anchorage device having lock fins or barbs to secure the anchor in position at biological tissue;

figure 50 illustrates two surgical cord anchors connected together by a knotless loop formed from implantable fibres or yarn; figure 51 illustrates three anchorage devices of figure 50 connected together to form an array by medical cord formed as an endless loop; and

figure 52 is a flow diagram illustrating the steps of an optional rapid

manufacturing process for the present implantable devices.

A number of different types of implantable surgical cord anchors are disclosed in this document. The anchors may be manufactured using a number of different techniques, including casting (for example, lost- wax casting) and machining, or indeed other methods such as those mentioned elsewhere in this document. However, it may be preferred to employ a rapid manufacturing process for manufacturing one or more of the disclosed anchors. Rapid manufacturing processes offer a number of advantages over processes that have previously been used to manufacture such anchors, particularly in that they facilitate the formation of features which it might not otherwise be possible to construct. Turning firstly to figure 1, there is shown a longitudinal cross-sectional view of a surgical cord anchor according to an embodiment of the present invention, the anchor indicated generally by reference numeral 10. The implantable surgical cord anchor 10 comprises an elongate main body or outer housing 12 which can be pressed or screwed into biological tissue. The main body 12 is also shown in the perspective view of figure 2, the sectional views of figure 3 (where it is shown in the same orientation as figure 1) and figure 4 (which is viewed in a direction perpendicular to that shown in figure 3), and figure 5, which is an enlarged plan view. An externally projecting helical thread 13 extends around part of the main body 12, and the body includes a distal end 15 which is tapered, to facilitate driving of the body 12 into body tissue. An internal cavity or chamber 14 extends internally along a region 15 of the main body.

The anchor 10 also comprises an inner component 16 which is movable both axially and rotationally within the cavity 14 of the main body 12. The inner component 16 is also shown in the perspective view of figure 6, the front view of figure 7 (where it is illustrated in the same orientation as figure 1), the side view of figure 8 and the enlarged plan view of figure 9. The inner component 16 can be inserted and withdrawn from the inner cavity 14 via axial movement, and rotated when inserted within the inner cavity 14. Cooperating locking components 18 and 20 are provided at an internal facing surface 22 of the inner cavity 14 of the main body 12, and an external facing surface 24 of the inner component 16, respectively. The inner component 16 can be locked in position axially within the main body 12 via engagement of the locking components 18 and 20.

The inner component 16 comprises means to receive a surgical cord which is indicated in broken outline in figure 1, and given the reference numeral 25. The surgical cord 25 may be looped or hooked around a portion of the inner component so that it can be secured to the anchor 10. In the illustrated embodiment, the inner component 16 comprises an aperture 26 which extends through the inner component in a direction generally perpendicular to a main axis 28 of the component. The aperture 26 is shaped to receive the surgical cord 25 so that, when the inner component 16 is inserted into the main body 12 and rotated to lock it in place (figure 1), the surgical cord is securely clamped between the main body and the inner component.

.

The structure and method of operation of the anchor 10 will now be described in more detail. The main body 12 is a generally tubular body defining the internal cavity 14. The inner component 16 takes the form of a plug-type member which is inserted into the cavity 14, and then rotated to lock it in position and prevent release of the inner component from the main body. To this end, the inner component 16 comprises a drive feature in the form of a slot 30 at a proximal or upper end 32, which can be engaged by a drive tool (not shown). The drive tool is used to translate the inner component relative to the main body 12 within the cavity 14, and for rotating the inner component. The locking component 18 takes the form of a groove, channel or recess formed in the internal surface 22 of the main body 12. The other locking component 20 takes the form of a protrusion such as a key, dog, finger or flange formed on the external surface 24 of the inner component 18. The key 20 can be located in the groove 18 for locking the inner component 18 against axial movement relative to the main body 12. It will be understood however that the groove 18 may alternatively be provided on the inner component 16, and the key 20 on the main body 12. The anchor 10 comprises a plurality of locking components in the form of two pairs of grooves 18 and corresponding locking keys 20, which are spaced 180° apart around the circumference of the main body 12 and the inner component 16, respectively. Other spacings and numbers of groove 18/key 20 pairs may be provided.

The groove 18 comprises an axially extending portion 34 along which the locking key 20 travels during insertion of the inner component 16 into the cavity 14, and a locking portion 36 which extends transversely (generally perpendicularly) to the axial portion 34. The locking key 20 prevents the inner component 16 from moving axially relative to the main body 12 when located in the locking portion 34 of the groove 18. This prevents the inner component 16 from being separated from the main body 12. The groove 18 also comprises a detent 38 for the locking key 20, which restrains the inner component 16 against both axial and rotational movement relative to the main body 16. The detent 38 communicates with the locking portion 36 of the groove so that, as the locking key 20 moves along the locking portion 36, it enters the detent 38, where it is captured. The detent 38 effectively forms a pocket which opens on to the locking portion 36 of the groove 18, and extends in an axial direction towards a proximal end 40 of the main body 12.

The inner component 16 is inserted into the main body 12 by aligning the locking keys 20 with the axial portions 34 of their respective grooves 18. The inner component 16 is then translated axially relative to the main body 12, the keys 20 travelling along the axial portions 34 of the grooves 18. Rotational movement of the inner component 16 relative to the main body 12 is, at this stage, prevented by side walls of the axial portion 34 of the groove 18. When the inner component has been fully inserted into the main body 12, the keys 20 are located at an intersection 42 between the axial groove portion 34 and the locking portion 36. Rotation of the inner component 16 using the drive tool will then cause the locking keys 20 to enter the locking portion 36. The inner component 16 is rotated until the keys 20 axially align with the detents 38. An axial force on the inner component 16 in the proximal direction will then cause the keys 20 to enter the pockets, where further axial and rotational movement will be prevented. The inner component 16 is thus securely coupled to the inner body 12, to clamp the surgical cord 25 to the anchor 10. The surgical cord 25 can be released from the anchor 10 by repeating the above steps in reverse. An upset in the form of a lip, rib, ledge or finger 44 (figure 4) is provided at an entrance 45 to the groove 18, which defines a restriction to passage of the respective locking key 20. One or both of the locking key 20 and the lip 44 may be deformable, by appropriate selection of materials. In this way, the locking key 20 and/or lip 44 may be deformed or deflected so that the locking key can pass the lip. This serves for retaining the locking key 20 in the groove 18, and so may resist separation of the main body 12 and the inner component 16 until such time as the locking key 20 is located in the detent 38. However, the lip 44 also has a rounded profile, to facilitate passage of the locking key 20. A further such upset in the form of a lip 46 is positioned in the groove 18, in the transverse locking portion 36. This lip 46 resists return movement of the locking key 20 along the locking portion 36.

The internal surface 22 of the main body 12 includes portions 48 which taper or which are inclined relative to a longitudinal axis 50 (figure 3) of the main body, and which are configured to cooperate with the external surface 24 of the inner component 16. In the illustrated embodiment, the external surface 24 of the inner component 16 also includes portions 52 which taper or which are inclined relative to the longitudinal axis 28 of the inner component, and which are configured to cooperate with the tapered portions 48 of the main body 12. In variations on the illustrated embodiment, only the internal surface of the main body may taper or may be inclined relative to the longitudinal axis of the main body.

The tapered portions 48 of the main body 12 are defined by ramps, wedges or the like which extend into the internal cavity 14. In a similar fashion, the tapered portions 52 of the inner component 16 are defined by ramps, wedges or the like on the component. There are two pairs of ramps 48, 52 which are spaced 180° apart around the circumference of the main body 12 and the inner component 16, respectively. Other spacings and numbers of ramps 48/5Ό may be provided. The tapered ramps 48, 52 provide an enhanced engagement of the surgical cord 25. In particular, axial movement of the inner component 16 relative to the main body 12 provides an enhanced clamping force on the surgical cord positioned between the surfaces, which is compressed and so 'squeezed' between the ramps. The ramps 48 and 52 have corresponding tapers, so that a taper angle of the ramps is the same. Also, the taper angles are substantially constant in a direction along the length of the main body 12 and inner component 16. However, if desired the taper angles may vary in said directions. The ramps 48 taper in a direction towards the proximal end 40 of the main body 12. This provides an enhanced engagement of the surgical cord 25 positioned between the ramps 48, 52. This is because, in use, the surgical cord 25 passes down through an opening 41 in the proximal end 40 of the main body 12, along the space 54 defined between one of the pair of ramps 48 and 52, through the aperture 26, back up the space 54 defined between the other pair of ramps 48, 52 and out of the opening 41. When the surgical cord 25 is tensioned during use, an axially directed force may be exerted on the inner component 16 by the surgical cord, which urges the inner component towards the proximal opening 41, thus enhancing a clamping force on the cord 25 positioned between the ramps 48 and 52. Spaces 54 are defined between the ramps 48 and 50, for receiving the cord 25. The ramps 48 describe a width dimension of the internal chamber 14 of the main body 12, which decreases in a direction towards the proximal opening 45. The ramps 52 on the inner component 16 taper in a direction towards the proximal end 32 of the inner component, and describe an external width dimension of the inner component, which dimension decreases in a direction towards the end 32.

As can be seen from figures 2 and 5, the ramps 48 on the main body 12 curve in a direction around a circumference of the body, and are generally concave. The ramps 52 on the inner component 16 are similarly curved, and convex. This is of particular use for clamping a surgical cord 25 having a round or elliptical shape in cross-section, as the space 54 defined between the ramps 48, 52 has a non-constant radial width. This tends to bring the cord 25 into a central position on the ramps 48 and 52, so that it can be securely clamped without damage to the cord. Turning now to figure 10, there is. shown a longitudinal cross-sectional view of part of a surgical cord anchor according to another embodiment of the present invention, the anchor indicated generally by reference numeral 10a. Like components of the anchor 10a with the anchor 10 of figures 1 to 9 share the same reference numerals, with the addition of the suffix 'a'. Only the substantive differences between the anchor 10a and the anchor 10 will be described herein. Figure 10 shows a main body 12a of the anchor 10a. The anchor 10a also comprises an inner component (not shown), which is of like construction to the component 18 of the anchor 10. The body 12a differs from the body 12 of the anchor 10 in that it does not include upsets in the form of lips either at an entrance 45a to a groove 18a in the body, or in a locking portion 36a extending transverse to an axial portion 34a of the groove.

Turning, now to figure 11, there is shown a perspective view of a surgical cord anchor according to another embodiment of the present invention, the anchor indicated generally by reference numeral 10b. Like components of the anchor 10b with the anchor 10 of figures 1 to 9 share the same reference numerals, with the addition of the suffix 'b'. Only the substantive differences between the anchor 10b and the anchor 10 will be described herein.

The anchor 10b is also shown in figure 12, which is a partial longitudinal cross-sectional view taken in the direction of the arrows A-A of figure 1 1. Additionally, figure 13 is a perspective view of a main body 12b forming part of the anchor 10b, illustrated in the same orientation as in figure 1 1 ; and figure 14 is a perspective view of an inner component 16b forming part of the anchor 10b, and again illustrated in the same orientation as in figure 1 1. As with the anchor 10a of figure 10, the body 12b does not include upsets in the form of lips either at an entrance 45b to a groove 18b in the body, or in a locking portion 36b extending transverse to an axial portion 34b of the groove. However, the body 12b may include such upsets if desired. In this embodiment, tapered ramps 48b of the main body 12b include planar (non-curved) portions 56. In addition, tapered ramps 52b of the inner component 16b also include planar portions 58. Spaces 54b are defined between the planar portions 56, 58 of the ramps 48b, 52b and have a constant width. This may be of particular use for clamping a surgical cord (not shown) having a constant width, or a portion of a constant width. Such may be the case where the surgical cord (or portion) is rectangular in cross-section, having flat opposed surfaces which can abut said surfaces of the main body and inner component.

The anchors of figures 1 to 14 may suitably be manufactured using a rapid prototyping process, such as will be described below. This may facilitate formation of a number of the features of the anchors, particularly tapered surfaces and locking components such as the locking grooves. However, other manufacturing techniques may be employed, including but not limited to casting (such as lost- wax casting) and machining, or indeed other methods such as those mentioned elsewhere in this document.

Referring now to figure 15, an implantable fixation anchor 100 in accordance with another embodiment of the present invention is shown. The anchor 100 comprises an elongate body 102 from which extend externally projecting helical threads 101 provided over the full length of body 102. A first end 103 of anchor 100 is tapered so as to be driveable into body tissue via threads 101.

Referring to figures 16 and 17, a closed elongate cavity 104 or through-bore extends through the body 102 between the first and a second end 105. The cavity 104 is enlarged at the second end 105 to provide a driving region 201 formed with a polygonal (such as a hexagonal) cross sectional profile to enable the device 100 to be driven into the anchorage site using an appropriate delivery tool (not shown) having a suitable drive head that engages into the region 201. A bar 200 is positioned towards second end 105 within the drive region 201 and projects across the full internal diameter of region 201 from a first side 300 to a second side 301 so as to form a bridge integral with the body 102. The bar 200 is non-linear and comprises a central hump to receive a suture 302 or other elongate element such as a synthetic loop, cord or tissue such as a ligament or tendon. A significant advantage of this design is the internalising of the driving end of the anchor within the anchor itself, so that the thread can occupy more of the outside surface of the anchor thus increasing the strength of the anchor attachment to the bone. Alternatively, the length of the anchor can be shortened such that the resulting anchorage strength is the same or not less than that of an anchor with an external driving end. In certain situations it is advantageous for the anchor to be as short as possible and this is achievable with the present devices. Figures 18 to 20b illustrate a further embodiment of the present invention being a second type of fixation anchor 400 configured to accommodate a bone screw 500. The anchor 400 comprises an upper main body 401 having an aperture 404 formed therein towards one end. A head section 402 extends from the main body 401 and comprises two lateral curved flanges 403 with hooked portions 405 configured to receive and engage looped sutures, cords, tendons, ligaments and the like.

Referring to figure 19, a cylindrical sleeve 503, which fits into a hole made in the bone, extends perpendicular to the planar head 402 and upper main body 401. Sleeve 503 is dimensioned so as to receive a bone screw 500 inserted through aperture 404. Screw 500 comprises external threads 501 to engage and further anchor device 400 within the bone. A screw head portion 504 enables screw 500 to be driven into the bone. The perimeter of aperture 404 at body 401 comprises a tapered or a chamfered surface 502 to mate with the underside tapered head 504 of screw 500 such that the upper surface 506 of screw 500 is capable of sitting flush with the upper surface of 505 of anchor 400, when fixed in position at the bone site.

Figure 20a illustrates the anchor 400 of figures 18 and 19, fixed in position at a bone site 602. In use, a ligament 601 may be anchored in position at the bone site 602 via a fibrous loop 600, including in particular a loop formed from a continuous yarn strand in which the ends of the yarn are arrayed within the looped structure so as to provide a continuous or knotless loop configuration. Alternatively a loop may be captive at one end within the ligament 601 , and still be retained by the device as shown in Figure 20b.

Figures 21a to 21 c illustrate a further embodiment of an implantable surgical cord anchor capable of securing medical cord to a biological tissue site. The anchor comprises a substantially cylindrical outer housing 700 that has a plurality of windows 703 extending along the length of the device from a first end 705 to a second end 704. The windows 703 extend through the sidewalls of the housing 700 from outer surface 717 to internal facing surface 718 that defines an internal chamber 719 extending within housing 700. Chamber or internal cavity 71 is open at second end 704 and first end 705.

The internal cavity 719 is configured to receive elongate lugs 701. Lugs or insert 701 comprises radial projections 708 (optionally in the form of cylindrical extensions) that extend from a central column 709 between a first end 710 and a second end 711.

According to the design of the outer body, central column 709 is divided into two, three or more elongate segments extending the length of insert 701 with each segment being circumferentially separated by elongate gap regions 722, each extending axially from first end 710 to second end 711. Insert 701 is capable of being accommodated within internal chamber 719 such that each barb 708 is aligned to sit within each respective window 703 such that a radially outermost end 720 of each barb 708 does not project beyond the outer surface 717 of housing 700 and is at least flush or even recessed relative to outer surface 717. To increase the frictional contact with the anchorage site, outermost end 720 of each barb 708 is textured, profiled or ridged. Additionally, projections 708 may comprise a single or a plurality of pointed projections that may be curved or profiled to inhibit the anchor assembly of figure 21a to 21c from being withdrawn axially from the bone axially. An elongate wedging insert 721 is configured to be inserted axially within internal bore 712 defined by the axial segments of insert 701. Wedge insert 721 comprises a cylindrical central core 713. Radially projecting fins 714 extend from central column 713 axially along its length from first end 716 to second end 715. The cylindrical core 713 is tapered axially along its length to form a frustoconical configuration. Additionally, central bore 712 of insert 701 is also tapered axially to mate with the tapered column 713 of the wedge 721. First end 705 of housing 700 comprises four (or more) radial flanges 706 that project inwardly to partially close the open end 705. A plurality of receiving slits 707 extend between flanges 706 and are dimensioned to receive fins 714 of wedge insert 721 when the insert 721 is driven axially into internal bore 712. With insert 701 inserted within chamber 719 of housing 700, as wedge insert 721 is advanced axially into bore 712 the barbs 708 are forced radially outward through windows 703 to lock the anchor in position at the biological tissue (bone). A through-bore or top loop (not shown) may be positioned at a region of wedge inserts 7 1 to enable a suture or other medical cord to be threaded, looped or secured at insert 721 and to be entrapped within housing 700 as insert 721 is accommodated within the insert 701 which in turn is locked in position within housing 700. Alternatively, a hook or loop (not shown) may extend from first end 705 of housing 700 to receive the suture.

Figures 22a and 22b respectively illustrate a surgical cord anchor 800 according to a further embodiment and a cross section of the same. The elongate device 800 comprises externally projecting threads 804 extending between a first pointed end 802 and a second driving end 803. Anchor 800 comprises an internal cavity 805 extending over a region of the length of the device. Two holes 806 diametrically positioned are made in device 800. A third opening 809 into internal cavity 805 is formed at second driving end 803. The cross section of opening 809 is irregular to allow an instrument (not shown) to drive the anchor into bone and may also be polygonal, for instance hexagonal or octagonal. A cross-bar or flange 807 projects across the internal chamber 808 from the internal facing surface 810 as illustrated in the cross sectional view through B-B. Cross-bar 807 is configured to receive a suture or medical cord (not shown) that is inserted into the internal chamber via opening 805. A double-eyed tool (not shown) is capable of being inserted through opening 809 with one eye either side of the bar 807 to draw the suture or medical cord over the cross-bar 807 as it is threaded through the internal chamber 805 via the two holes 806, and then drawn with the tool to emerge from opening 809. The holes 806 are rectangular in shape with a rounded top 81 1 , but can also be oval. The bottom 812 of the hole 806 is close to the cross bar 807 such that an upper edge 813 of bar 807 is approximately aligned with the straight bottom edge 812 of hole 806 when viewed from the side of the device 900 to facilitate the threading of suture or cord as described.

Figures 23 to 24b illustrate a further embodiment of an implantable cord anchorage device. The anchor comprises an outer housing 1003 to receive a removable inner component 1000. Threads 1004 extend externally along the length of housing 1003 between first end 1009 and second end 1008 to allow the device to be screwed into a bone site for anchorage. An internal bore 1007 extends within housing 1003 between first and second ends 1009, 1008. A pair of diametrically opposed locking channels 1005 are recessed into the internal facing walls 1011 that define through-bore 1007. The opposed channels 1005 extend substantially from first end to second end 1009, 1008. Channels 1005 terminate at respective locking grooves 1006 that extend perpendicular to channels 1005 and extend part circumferentially around the internal bore 1007. Internal bore 1007 is tapered radially inward from first end 1009 to second end 1008.

Insert 1000 also comprises a radially decreasing taper along its length that corresponds to the internal taper of bore 1007. A pair of opposed locking flanges 1002 project radially outward from a lower region of insert 1000. Insert 1000 is effectively divided into two axial halves with each half being separated by a compression region or gap 1001 defined by opposed faces 1012 that are textured or profiled to increase frictional contact with the cord received within gap 1001 so as to hold it securely when anchored in position. That is, the surgical cord (not shown), accommodated within gap regions 1001 is trapped against the wedging surfaces 1012 as the insert segments 1000 are compressed radially inward together. This acts to lock the cord (not shown) in position at the device. According to further embodiments insert 1000 is formed as a unitary body and comprises for example male and female type connection flanges (not shown) that connect each half 1000. In use, insert 1000 is inserted within bore 1007 such that flanges 1002 engage into grooves 1005. When fully inserted as illustrated in figure 24b, insert 1000 is rotated so that flanges 1002 slide within locking grooves 1006 according to a bayonet type lock. Accordingly, insert 1000 may not be axially withdrawn from housing 1003 without the required rotational unlocking movement.

Drive means (not shown) are also provided towards one of the device of figures 23 to 24b to enable the device to mate with a suitable driving tool (not shown) and be driven into the anchorage site. Figures 25 to 28 illustrate a further embodiment of the present medical cord anchor comprising an insert 1100 to be locked in position within an outer anchorage component 1101. Housing 1 101 comprises externally projecting threads 1106 to enable the device to be screwed into the biological tissue and anchored in position. A through-bore 1104 extends longitudinally through housing 1101 and is sized and shaped to receive insert 1100 such that an outer surface 1107 of insert 1100 fits snug against the walls 1201 that define internal bore 1104. A locking channel 1105 is indented on inner wall 1201 at an upper region of through-bore 1 104. Locking channel 1105 terminates at a locking recess 1200 that extends perpendicular to channel 1105 with recess 1200 extending a short axial distance along the length of the elongate housing 1101.

Insert 1 100 comprises a cross-bar 1103 extending from an upper end 1109. A through-bore 1 102 extends through insert 1100 perpendicular to its main length and approximately midway between upper end 1 109 and second end 1108. Bore 1102 is configured to receive the surgical thread or biological cord that is then secured to the device as insert 1100 is locked in position at outer component 1 101. The length of bar 1103 is greater than the diameter of upper end 1 109 of insert 1 100 so as to extend radially beyond outer surface 1 107.

Insert 1 100 and through-bore 1 104 are tapered along their length such that a cross sectional diameter of the bore 1 104 and insert 1 100 decreases from the upper end to the lower end in the axial direction. Referring to figures 27 and 28 as insert 1100 is inserted within bore 1104, bar 1 103 is engaged within channel 1105. Insert 1100 is then rotated axially through 45° such that bar 1 103 slides within channel 1 105. Once rotated fully, bar 1 103 engages into recess 1200 such that insert 1 100 moves a small distance in the return axial direction relative to the direction of insertion within housing 1101. This locks the insert in position and provides that disengagement is possible only with a short axial movement in a first direction, followed by axial rotation and then axial withdrawal. Driving means (not shown) are also provided towards one end of the device of figures 25 to 28 to enable the device to mate with a suitable driving tool (not shown) and be driven into the anchorage site.

Figures 29 to 31 illustrate a further embodiment of a medical cord anchor being similar to the embodiment described with reference to figures 25 to 28 in which an insert 1500 is releasably locked in a position within an outer housing component 1501 that comprises threads 1504 projecting from its external facing surface, insert 1500 comprises the same through-bore 1509 which, like the embodiment of figures 25 to 28, is configured to receive the surgical cord which is looped through bore 1509 and secured in position at the anchorage device when insert 1500 is locked in position at outer component 1501. Housing 1501 also comprises a centrally extending axial bore 1505 defined by inner walls 1602 that taper inwardly from a first end to a second end along the length of housing 1501. A pair of diametrically opposed channels 1503 are recessed into the walls 1602 and extend over nearly the entire length of housing 1501. Each channel terminates at a locking groove 1600 that extends perpendicular to axial channels 1503. Insert 1500 comprises a pair of diametrically opposed notches 1502 that are shaped and dimensioned to be received within the respective channels 1503 as the insert 1500 is inserted within bore 1505. Notches 1502 are positioned towards a second end 1507 of insert 1500 with respect to first end 1508. Bore 1509 extends radially through insert 1500 just above the axial mid-point and towards end 1508. Two cut-out portions 1510 extend from end 1508 to the entry and exit openings of bore 1509. When the surgical cord is threaded through bore 1509, the cut-out sections 1510 allow the cord to sit partially within the axial perimeter of insert 1500 defined by outer surface 1506. The locking action and cord anchorage is provided as the insert 1500 and surgical cord is accommodated within bore 1505 so that the cord is entrapped between outer surface 1506 and bore walls 1602 as it protrudes through each end of the insert bore 1509.

As with the embodiment of figures 25 to 28, locking of the insert 1500 at housing 1501 is provided by axial insertion of insert 1500 into bore 1505 followed by axial rotation through approximately 45° to allow notches 1502 to firstly slide axially within channels 1503 and then to slide within locking grooves 1600. The insert 1500 is then configured to move slightly in the reverse axial direction as lugs 1502 slide a short distance in the return axial direction within locking recess 1601 extending from locking grooves 1600. As with other embodiments, driving means (not shown) are provided towards one end of the device of figures 29 to 31 to enable the device to mate with a suitable driving tool (not shown) and be driven into the anchorage site. A further embodiment of the biological or synthetic surgical cord anchor is described with reference to figures 32 to 34. The anchor 1800 comprises an elongate housing 1801 that has a centrally extending axial bore 1803 defined by cylindrical walls 1803. Bore 1807 has an increased cross sectional area towards one end 1802 and comprises a polygonal, such as a hexagonal, cross sectional profile and configured to receive an Allen key type driving tool. Threads or radial projections 1901 extend radially from the outer surface of housing 1801 to provide frictional contact with the surrounding biological tissue into which anchor 1800 is pushed or screwed. An insert 18Q5 is configured to be received partially within one end of housing 1801 at a second end opposed to the driving end. Insert 1805 comprises a conical pointed section 1809 that is formed integrally with a substantially cuboidal section 1804 extending from the end face 2001 of cone 1809. An eyelet 1900 extends through the cuboidal section 1804 and is designed to receive the surgical cord 1806 that may be looped through it. A width of flange 1804 corresponds to approximately the diameter of bore 1807 such that insert 1805 is held in position within housing 1801 by the frictional contact between the outer surface of section 1804 and inner walls 1803 that define bore 1807. Insert 1805 is securely locked to housing 1800 as tension is applied to cord 1806. A locking shoulder 2000 that is created as section 1804 does not extend across the full diameter of the cone end surface 2001 such that locking shoulder 2000 abuts against the end 1808 of housing 1800. Accordingly, insert 1805 is prevented from being pulled through bore 1807 by shoulder 2000 mating against end 1808.

Figures 35a to 35d illustrate a yet further embodiment of a surgical cord anchor in which an insert 2100 is accommodated and locked in position within an outer housing component 2107 that is in turn screwed or pressed into biological tissue (bone) in order to anchor or fixate the surgical cord at a desired site. The insert 2100 comprises a substantially cylindrical geometry but with two diametrically opposed cut-out sections 2103 extending axially along the length of insert 2100 and radially inward from outer surface 21 13. Cut- out sections 2103 are defined by curved surfaces 2114 that correspond in profile to the outer surface of a cylinder. A driving channel 2102 is recessed into an upper face 2117 at a first driving end 2106 of insert 2100. A central region of insert 2100 at a second end 2105 is cut-away to define a bridge section 2104 extending between legs 21 15 that terminate at second end 2105. Two diametrically opposed locking lugs 2101 project radially outward from the part cylindrical outer surface 2113.

Housing 2107 is also substantially cylindrical and comprises threads 2108 externally projecting from a cylindrical outer surface 2118. A through-bore 2119 extends centrally through housing 2107 and is open at both ends. A locking channel 2110 is recessed into the inner cylindrical wall 2116 that defines bore 2119. Channel 2110 extends part

circumferentially over a region of wall 2116 and is terminated at one end by an axially extending locking groove 2111 extending a short distance perpendicular to channel 2110.

A driving end of housing 2107 comprises radially inward projecting shoulders 2112 that partially close the opening 2109 into bore 2119. The shoulders 21 12, in cross section, comprise a curved profile corresponding to the curvature of cut-out sections 2103 such that the cross sectional profile of insert 2100 is almost identical to the cross section profile of opening 2109. To anchor the cord (not shown) in position, it is first looped around bridge section 2104 and is accommodated axially within part-cylindrical cut-out sections 2103. Insert 2100 is pre-loaded within housing 2107 so as to provide a unitary assembly with the insert 2100 captured (i.e. prevented from disassembly) but capable of rotation and slight axial movement within housing 2107. Using a screwdriver or other driving tool (not shown) that engages into driving channel 2102 insert 2100 is then rotated such that lugs 2101 slide within diametrically opposed channels 21 10 to be accommodated finally within locking grooves 211 1. Channel 2102 may also provide a means of driving the unitary pre-loaded device into the anchorage site (bone). The surgical cord (not shown) is then pulled to displace insert 2100 a short distance axially in the return direction to lock lugs 2101 within grooves 21 11. An alternative or secondary locking action is also provided by shoulders 2112 that trap (and sit over) insert 2100 which has been rotated axially such that the corresponding cross sectional profiles are misaligned to trap the cord between the shoulders 2112 and the insert (face 2117).

Figures 36 and 37 illustrate a further embodiment of a suture anchor comprising an outer component or housing 2200 having external threads 2202. The housing 2200 comprises an internal bore 2205 having internally projecting right-hand threads 2206 extending axially over its length. One end of the bore 2205 comprises a greater diameter and a polygonal cross sectional profile to receive a polygonal driving tool such as an Allen key tool to drive the anchor into the biological site. A pointed engaging insert 2203 is partially

accommodated within bore 2205 at one end of housing 2200. Insert 2203 comprises an eyelet 22Q4 to receive a suture or surgical cord 2210. One half of insert 2203 comprises an internal bore 2212 that also comprises internal screw threads 2209. Insert 2203 is capable of sliding movement 221 1 within a region of housing bore 2205. A driving shaft 2214 extends internally within bore 2205 between driving end 2201 and insert 2203. External right-hand screw threads 2215 are formed at one end of shaft 2214 to cooperate with threads 2206 to enable shaft 2214 to be driven in the axial directions through bore 2205. Shaft 2214 comprises a driving head 2207 to receive a screwdriver or other driving tool to enable shafts 2214 to be rotated 2213 within bore 2205 via screw threads 2206 and 2215. Reverse, left-hand screw threads 2208 are formed at a second end shaft 2214 and are configured to engage corresponding internally projecting threads 2209 of insert 2203. As shaft 2214 is rotated 2213, insert 2203 is drawn axially 2211 into housing 2200 via cooperation of screw threads 2209 and 2208. Surgical cord 2210 is threaded through eyelet 2204 and sits within channels or tunnels 2300 that extend axially along the length of housing 2200.

Figures 38 to 39 illustrate a surgical cord anchor according to further embodiments. The anchor comprises an external housing 2401 having an eyelet 2400 extending at a mid region along the length of the device. One end of the anchor is pointed 2402 to enable the device to be pushed or threaded into biological tissue such as bone via screw threads 2406 that extend externally over housing 2401. An inner component 2403 is accommodated within an axial bore 2407 extending within housing 2401. Inner component 2403 also comprises an eyelet 2404 extending perpendicular to through-bore 2407 and aligned parallel with eyelet 2400. As insert 2403 is moved axially 2405, the eyelets 2404, 2400 misalign and a suture or surgical cord (not shown) is trapped between the eyelets 2400, 2404. Figures 40 to 42 illustrate a yet further embodiment of the anchor described with reference to figures 36 and 37. According to the further embodiment, shaft 2214 comprises a radially enlarged flange 2601 positioned at the second end opposed to the driving end 2207. Flange 2601 is locked or embedded within insert 2203 such that axial movement of shaft 2214 provides a corresponding axial movement 2211 of insert 2203 at least partially within internal bore 2205 extending within housing 2200. Shaft 2214 is moved axially via drive end 2207 and the cooperation of screw threads 2206 and 2215. Accordingly, the suture cord 2210 threaded throughout eyelet 2204 is entrapped at the anchor as eyelet 2204 is received axially within bore 2205. Figures 43 to 45 illustrate a yet further embodiment of the surgical cord anchor comprising an outer component 2911 and a moveable inner component 3100. Outer component 2911 also comprises a bore or internal cavity 2901 extending centrally through the device. Additionally, channels or tunnels 2909 extend axially through the device 2900 and are configured to receive the surgical cord or suture 2905 that is threaded and looped through channels 2909. Preferably, the device comprises four suture channels or bores 2909.

Internal bore 2901 comprises two radially flared regions 2910 axially separated along the length of bore 2901.

Insert 3100 comprises an elongate shaft 2902 and a pointed conical end section 2903. End section 2903 comprises rearwardly projecting shoulders 2906 such that insert 3100 comprises a harpoon-like shape and is configured to seat against a domed end region 2913 of outer component 291 1. Shaft 2902 comprises two radially extending notches 2912 that are sized and shaped to sit snug within the radially flared regions 2910 of bore 2901. A driving end of shaft 2902 comprises a blind bore 2904 having internally projecting threads to engage with a driving tool that may be secured to shaft 2902. As the driving tool is pulled, insert 3100 is withdrawn axially 2914 onto outer component 291 1. The surgical cord 2905 threaded within channels 2909 is trapped between the harpoon like end section 2903 of insert 3100 and the domed engaging end 2913 of housing 2911. Insert 3100 is held in the locking position by the frictional contact between notches 2912 and flared regions 2910. Further locking is provided by shoulders 2906 seating under collar 2907 extending around the central domed section 2913.

Figures 46 to 48 illustrate a further embodiment of the suture anchor comprising an outer component housing 3201 and a moveable insert 3200. Housing component 3201 comprises an internal cavity 3206 extending, substantially the length of the device. The cylindrical housing 3201 comprises two diametrically opposed windows 3208 extending through side walls 3209 that define internal cavity 3206. A pair of axles 3203 extend perpendicular to the main axial length of housing 3201 to traverse or bridge cavity 3206. Axles 3203 are anchored in position within walls 3209. An arm or barb 3202 is rotatably mounted upon each respective axle 3203 at one end. Each barb 3202 comprises a length and width sufficient to allow it to be displaced through window 3208 via rotation about axle 3203. A locking channel 3205 and locking groove 3300 are recessed into the inner surface of wall 3209 as described earlier with reference to other embodiments.

Insert 3200 is similar to the insert described with reference to figures 24b, 29 and 35a. A pair of diametrically opposed locking flanges 3400 is configured to be received and locked in position within channels 3205 and groove 3300 when insert 3200 is accommodated within cavity 3206 and rotated axially. Insert 3200 comprises an end abutment region 3302 having tapered shoulders 3301 configured to contact anchoring barbs 3202 as insert 3200 is advanced axially into cavity 3206. As shoulders 3301 contact the inwardly orientated surfaces 3303 of arms 3202, the arms 3202 are caused to pivot about axles 3203 so as to be deflected radially outward though windows 3208 to the position illustrated in figure 46. The barbs 3202 are maintained in the radially extended position as lugs 3400 are locked within locking groove 3300. The surgical cord (not shown) is anchored in position at the device 3200, 3201 being looped under the central bridge 3207 defined, in part, by bore 3204 extending through insert 3200. Also, the cord may be anchored in position at the site by passing the cord axially around the outer surface of the anchor such that the cord is trapped and embedded at the site by the barbs 3202 that extend radially outward. Figure 49 illustrates further embodiments of the surgical cord anchor comprising locking fins or barbs to anchor the device in position at biological tissue. The anchor comprises an outer component housing 3418 having a pointed end 3410 configured to engage into a bone site. As described previously with reference to other embodiments, the outer component 3418 comprises an internal cavity or bore 3420. A plurality of holes 3419 extend through the walls of housing 3418 into the internal cavity 3420. One or a plurality of inserts 3401, 3412 are accommodated within housing 3418 and capable of moving to extend radially outward through holes 341 . In particular, each locking barb or fin 3401 may be rotatably mounted via a pivot axle 3402 to extend and retract at hole 3419 so as to extend radially beyond the outer surface of housing 3418.

The anchor further comprises a wedging insert 3403 having an elongate shaft 3404 and a wedge extending radially from shaft 3404 having opposed camming surfaces 3405, 3406. Rotation of shaft 3404 axially 3422 provides rotation of camming surfaces 3405, 3406 within cavity 3420. The surfaces 3405, 3406 are aligned to contact inner facing surfaces 3407 or barbs 3401 such that as shaft 3404 rotates axially 3422, the barbs 3401 extend radially outward 3421 via pivoting axles 3402.

As an alternative to the opposed camming surfaces 3405, 3406 involving rotation 3422 of wedge insert 3403, radial displacement of barbs 3401 may be provided by an axial pulling motion using alternate wedge insert 3423. The insert 3423 comprises shaft section 3404 and a radially outward tapered section 3408 that terminates at a further shaft section 3409 of greater radius than shaft section 3404. Barbs 3401 are caused to extend radially outward

3421 as insert 3423 is pulled axially 3424 such that tapered section 3408 abuts against inner surfaces 3407 of barbs 3401.

According to an alternative embodiment, each locking fin 3401 may comprise a curved channel 3417 recessed into the respective inner surface 3407. In this embodiment, the wedging insert 3425 comprises an elongate shaft 3413 having radially extending lugs 3414 that are configured to engage into channel 3417 of each fin 3401. As shaft 3413 is rotated

3422 and pulled axially 3424 lugs 3414 engage and slide within channels 3417 to force the barbs 3401 radially outward 3421. Each barb 3401 may be formed and secured in position at housing 3418 independently. Alternatively each barb 3401 may be coupled to a neighbouring barb by a suitable connecting section 3412 such that the radial rotation 3421 of at least two barbs are coupled. Accordingly, a reverse rotation and axial movement retracts barbs 3401 into housing 3418 so as to allow the anchor to be removed from its anchored position to release the surgical cord in the event of a revision operation or corrective surgery.

As described previously, the surgical cord or suture may be attached to the various embodiments of the anchor device via hook or loop extensions, suitable eyelets or channels attached to or formed at the outer housing components or respective inserts. In particular, and referring to the embodiments of figure 49·, the cord may be anchored in position at the site by passing the cord axially around the outer surface of the anchor such that the cord is trapped between the outwardly projecting locking fins and the opposed walls of the bone cavity into which the device is embedded.

Figures 50 and 51 illustrate an array of medical cord anchors 3500 connected together to form a unitary assembly via one or a plurality of looped cords 3505. Each anchor 3500 is tapered along its length between a cord anchorage end 3502 and a pointed engaging end 3501. Threads 3503 extend externally between ends 3502 and 3501. A loop or eyelet 3504 extends from end 3502 and is formed integrally with the main length of the device 3500. Cord 3505 is looped around the eyelet 3504 of each anchor 3500 according to an endless or knotles.s loop configuration where the ends of the yarn or fibre that comprise cord 3505 are incorporated in the cord structure during the assembly process so that the cord 3505 is knotless and seemingly endless. A plurality of anchors 3500 may be coupled by a single piece of cord 3505 that is looped around each eyelet 3504 and formed into a knotless loop to provide an anchorage array. A further surgical cord, tendon or ligament may then be looped around cord 3505 as required. Anchor 3500 may have a closed aperture or an aperture with a slit (not shown) to allow a knotless loop to be hooked to the anchor 3500. When using such devices a surgeon may choose from an array of loops of different dimensions to suit a particular application. All the implantable devices of the subject invention can be manufactured by rapid processing, also know as rapid prototyping, rapid tooling or rapid manufacturing. However and as discussed above, other manufacturing processes may be employed. The present implantable components may be manufactured from a variety of different materials such as metals, metal alloys, plastics including natural and synthetic polymers (and which may be Poly-Ether-Ether-Ketone or 'PEEK'), powders and resins that may be resorbable or non- resorbable materials. Rapid processing enables the production of very intricate and complex design components that form part of a single component implantable device or an implantable device having at least one moving components as described herein.

Rapid manufacturing processes encompassed by the present invention include: three- dimensional printing, stereolithography, selective laser sintering, shape deposition manufacturing, direct metal laser sintering (DMLS), laminated object manufacturing and injection moulding. The present invention utilises a computer CAD system coupled to a processing machine to perform the step- wise fabrication and layer-by-layer construction of the implantable device under computer control.

Referring to figure 52, a process of rapid manufacturing is shown which comprises the following steps. Firstly, a 3D CAD representation of the device is created 3700 by a computer software package such as ProEngineer, SolidWorks or Autocad. The computer representation of the device is then sliced into layers of certain thickness, typically 0.1 to 0.25mm at stage 3701. These two-dimensional (2D) profiles are then stored in a triangulated (tessellated) format as a .STL file at stage 3702. Suitable software converts the .STL data to machine data at stage 3703 which are sent to the operation apparatus 3704 to generate each layer of the implant by a specific fabrication process 3705. The process is repeated many times, so as to build the implant/anchor layer-by-layer. The final step 3706 involves removing the device from the process apparatus, detaching support materials, and performing any necessary cleaning or surface finishing. The above processing steps may be undertaken according to any layer manufacturing process such that all components of the implantable device are manufactured and assembled simultaneously so as to obviate the requirement to assemble component parts resulting in undesirable joints, seams or other interfaces between individual components.

Various modifications may be made to the foregoing.

For example, further embodiments of the invention may comprise one or more features of one or more of the above described embodiments.

The anchors/fixation devices disclosed in this document may have a use in anchoring surgical items other than surgical cords; a wide range of different surgical items may be anchored employing the anchors/fixation devices of the present invention.

Claims

1. An implantable surgical cord anchor comprising:

a main body which can be pressed or screwed into biological tissue;

an internal cavity extending internally along a region of the main body;

an inner component movable both axially and rotationally within the cavity of the main body such that the inner component may be inserted and withdrawn from the inner cavity via axial movement and rotated when inserted within the inner cavity; and

cooperating locking components provided at an internal facing surface of the inner cavity of the main body and an external facing surface of the inner component such that the inner component is capable of being locked in position axially within the main body via engagement of the locking components.

2. An anchor as claimed in claim 1, in which the anchor is created by rapid manufacturing.

3. An anchor as claimed in either of claims 1 or 2, in which at least part of the internal surface of the main body tapers relative to a longitudinal axis of the main body, and is configured to cooperate with the external surface of the inner component.

4. An anchor as claimed in any preceding claim, in which at least part of the external surface of the inner component tapers relative to a longitudinal axis of the inner component, and is configured to cooperate with an internal surface of the main body.

5. An anchor as claimed in any preceding claim, in which:

at least part of the internal surface of the main body tapers relative to a

longitudinal axis of the main body and is configured to cooperate with the external surface of the inner component;

at least part of the external surface of the inner component is tapered relative to a longitudinal axis of the inner component; and

said internal surface of the main body and external surface of the inner component have corresponding tapers. -3&-

6. An anchor as claimed in any one of claims 3 to 5, in which the main body defines a proximal opening through which the inner component can be inserted into the main body, and in which said internal surface of the main body tapers in a direction towards the proximal opening.

7. An anchor as claimed in any one of claims 3 to 5, in which the main body defines a proximal opening through which the inner component can be inserted into the main body, and in which said internal surface of the main body tapers in a direction tapers in a direction away from the proximal opening.

8. An anchor as claimed in any one of claims 3 to 7, in which the inner component has a proximal end and tapers in a direction towards said end.

9. An anchor as claimed in any one of claims 3 to 7, in which the inner component has a proximal end and tapers in a direction away from said end.

10. An anchor as claimed in any preceding claim, in which a space is defined between said internal surface of the main body and said external surface of the inner component, which space is shaped to receive a surgical cord so that the main body and the inner component can exert a compressive clamping force on a surgical cord located in said space, when the inner component is located in the inner cavity of the main body.

1 1. An anchor as claimed in any preceding claim, in which at least part of said internal surface of the main body is curved in a direction around a perimeter of the body, and at least part of said outer surface of the inner component is curved in a direction around the perimeter of the component.

12. An anchor as claimed in any one of claims 1 to 10, in which at least part of said internal surface of the main body is planar, and at least part of said external surface of the inner component is planar.

13. An anchor as claimed in claim 10, or claim 11 when dependent on claim 10, in which the space has a non-constant width.

14. An anchor as claimed in claim 10, or claim 12 when dependent on claim 10, in which the space has a substantially constant width.

15. An anchor as claimed in any preceding claim, in which:

one of the locking components is a groove formed in or on one of the internal surface of the main body and the external surface of the inner component; and

the other one of the locking components is a protrusion formed in or on the other one of the internal surface of the main body and the external surface of the inner component;

in which the protrusion can be located in the groove for locking the inner component against axial movement relative to the main body.

16. An anchor as claimed in claim 15, in which the groove comprises an axially extending portion along which the locking protrusion travels during insertion of the inner component into the cavity, and a locking portion which extends transversely to the axial portion, the locking protrusion preventing the inner component from axial movement relative to the main body when located in the locking portion of the groove.

17. An anchor as claimed in either of claims 15 or 16, in which at least one upset is provided in the groove or at an entrance to the groove, which upset defines a restriction to passage of the locking protrusion in which the upset or the locking protrusion is deformed or deflected so that the protrusion can pass the upset.

18. An anchor as claimed in claim 17, when dependent on claim 16, in which a first upset is provided at an entrance to the groove, and a further upset is positioned in the transverse locking portion of the groove.

19. An anchor as claimed in any preceding claim, in which the inner component comprises means to receive a surgical cord such that the surgical cord may be looped or hooked around a portion of the inner component.