GB2573033A

GB2573033A - Improvements to orthopaedic pins

Info

Publication number: GB2573033A
Application number: GB1900229.4A
Authority: GB
Inventors: Lowth Stewart
Original assignee: Metlase Ltd
Current assignee: Metlase Ltd
Priority date: 2018-04-20
Filing date: 2019-01-08
Publication date: 2019-10-23
Anticipated expiration: 2039-01-08
Also published as: GB2573033B; GB2573011B; GB201900229D0; GB201806453D0; GB2573011A

Abstract

A device for illuminating an insertion site of an orthopaedic pin or wire 1000 comprising an ultraviolet illumination means, which is attachable to the orthopaedic pin or wire. The illumination means comprises a light guide 1001 extending along a length of the oprthopaedic pin or wire. The light guide may comprise one or more light scattering regions. The illumination means may comprise one or more UV light emitting diodes. The device may comprise a body comprising a passage or channel and may comprise a slot which extends laterally and in a direction transverse to a main axial direction of the passage or channel. The device may comprise a tubular shroud member 1002 which may have a closed upper end having a peripheral annual shelf to locate the body member. An apparatus for monitoring a pin site infection comprising a camera, means of attaching a camera to an orthopaedic pin or wire and a transmitter is also included.

Description

[0001] This invention relates to pins or wires for orthopaedic use.

Background of the Invention [0002] In the treatment of complex compound human or animal bone fractures it is known to stabilise a fractured bone using various different external frame structures which rigidly support separate ends of an individual bone, for example of an arm or leg. Typically, there is a rigid external frame outside of the limb, and attached to the external frame, a set of pins or wires which enter the patient’s body and are secured to parts of the bone in the fracture. Bone interfacing wires also sometimes known as Kirschner wires, or K wires, are slender (typically less than 4mm in diameter) cylindrical wires with a ground point at one end. While pins are sturdy larger diameter metal cylinders which generally include a threaded bone interfacing feature. In use, K wires are used to stabilise a bones position while pins are used in load-bearing applications, although many complex fractures may require a combination of both approaches.

[0003] Examples of known frame structures include the commonly used Ilizarov apparatus, and the known Taylor Spatial Frame apparatus.

[0004] Known pins and K wires are generally fabricated from rigid and stiff heavy gauge wire, typically of stainless steel or titanium alloy. The pins are generally driven through the skin (percutaneous pin fixation) and into the bone using a powered drill or a hand drill. A typical procedure comprises inserting a hollow tubular cannula into the soft tissue and pushing down to the surface of the bone. A drill shaft is then inserted into the cannula and a circular cylindrical cavity is drilled into the bone using an electric or hand drill. After removal of the drill shaft, a pin is then inserted into the bored cavity through the cannula and is screwed into the bone. The cannula is then removed leaving the pin in place having one end secured into the bone, a pin extending through the soft tissue radially outwardly from the bone, and a proximal end of the pin protruding out of the patient’s body. K wires differ in use to pins; their faceted point and slender

-2cross-section enables them to punch their own hole though soft tissues and bone, indeed they are frequently used to pilot prior to the insertion of larger diameter pins. In the use case of the Taylor Spatial Frame or Ilizarov apparatus the K wires are driven complete through the soft tissues and bone so that the wire protrudes from both sides of the limb perpendicular to the axis of the bone.

[0005] In external fixation procedures pins are secured to the bone with the length of the pins being approximately perpendicular to the main length axis of the bone, so that the pins extend approximately transversely relative to the main length of the bone, and through adjacent tissue, such as muscle, subcutaneous fat layers, and skin.

[0006] Because the pins pass through the skin into bone they form a potential passage for bacteria from the skin to migrate into the bone and cause an infection. This is known as pin tract infection. In mild pin tract infection, the area around the pin at the skin surface becomes red and swollen and may start to drain pus. Usually this infection clears up after removal of the pin.

[0007] However, if the infection is more serious, bacterial infection along the length of the K - wire or pin can occur and if bacteria reaches the bone this can potentially result in deep bacterial infection within the bone marrow which is difficult to treat. Beyond bacterial infection, the pin tracts also offer in vivo ingress sites for fungal and viral antigens.

[0008] Referring to figure 1 herein, there is shown in schematically in perspective view a human limb having inserted therein a plurality of Kirschner wires or pins 100. Each wire extends from a position outside the patient’s body, through the skin and subcutaneous layers, through the muscle and soft tissue and into the underlying bone where a distal end of each K wire is securely anchored into the bone. An arrangement two such K - wires at a same length position along a bone is used for fitment of a single ring of a known Ilizarov type external fixator, or a known Taylor Space Frame external fixator. The position 101 at which the pin breaks the surface of the skin enters the soft tissue is known as the pin site, and the region adjacent the pin, within the body is known as the pin tract.

-3[0009] The fitting procedure for known K - wires depends upon the application, and the size and gauge of the K wire. Generally, the K-wires comprises rigid circular or cylindrical rods, having sharpened points in the manner of a stake point. The points may have sharpened cutting edges so that when the K - wire is rotated, the sharpened edge cuts into the bone. Depending upon the size of the K wire, it may be appropriate to pre-drill a hole to a slightly smaller diameter than the diameter of the K - wire to avoid putting undue high stresses on the bone. Removal of the K - wires after healing of the bone can be done manually by gripping the external extending end of the K - wire with a twist and pull action with the twist being in the opposite rotational direction to that used during insertion of the K wire, or by a similar twist and pull action, but using a drill to grip the end of the K - wire.

[0010] Since the patient’s skin is broken, each K wire is a potential site of bacterial infection. Pin site infections are common part of using an external fixator. Infection is not a reflection of the cleanliness of a patient, and pin site infection can still occur even where strict cleanliness and sterilisation regimes are followed. The pin sites need daily care and cleaning, but fastidious cleanliness is still no guarantee of avoiding infection. Where a patient is resting at home, responsibility for pin site cleanliness generally rests with the patient themselves and the patient may not be able to recognise pin site or pin tract infection until the infection is well established, where it become painful and puss weeping. However, in treatment of pin site infection early diagnosis make it easier to treat.

[0011] Referring to figure 2 herein, there is illustrated schematically in cut away view from one side, fixation of a known K - wire into a length of bone, in which the position at which the K - wire protrudes from the skin is covered by a foam block to prevent the ingress of dirt into the pin tract region, as is known in the art.

[0012] The Kirchner wire or pin 100 is secured into a section 200 of dense bone surrounding a cavity containing bone marrow 201. The K - wire extends through the patient’s skin 202, through subcutaneous tissue 203, and depending

-4upon the method fixation can terminate in the dense bone 200, or can extend through the dense bone into the bone marrow 201.

[0013] A protruding proximal portion 204 of the K wire has attached to it a block of foam 205 and a clip 206 which attaches to the K wire at a fixed position along the wire, and compresses the foam on to the surface of the skin, preventing the ingress of dirt into the pin tract. An added benefit is that the pressure around the wound reduces skin and muscle movement - helping to reduce the pain and swelling caused by the hard pin material rubbing against the soft tissues of the body.

[0014] An object of specific embodiments and implementations according to the present invention is to reduce the infection rate due to pin tract infection when using orthopaedic Kirchner wires or pins of the type which are secured directly into a patient’s bone, particularly, although not exclusively in the context of known external fixators devices.

Summary of the Invention [0015] According to one aspect there is provided a device for illuminating an insertion site of an orthopaedic pin or wire, said device comprising:

an ultraviolet illumination means for illuminating said orthopaedic pin or wire and a region of a patient’s body immediately adjacent said pin or wire with far UVC ultra violet light, said ultraviolet illumination means being attachable to said orthopaedic pin or wire said illumination means comprising a light guide extending along a length of said orthopaedic pin or wire.

[0016] Preferably said illumination means comprises one or a plurality of ultra violet light emitting diodes, lamps or bulbs, and preferably one or more ultraviolet C light-emitting light sources.

-5[0017] Said illumination means may comprise an ultraviolet light guide.

[0018] Said ultraviolet light guide may comprise a tubular light guide which fits around said orthopaedic pin or wire.

[0019] Said tubular light guide may comprise one or a plurality of light scattering regions for directing light out of said light guide in a direction away from a main central axis of said light guide.

[0020] Said illumination means may comprise a fibre-optic cable or light pipe structure.

[0021] The device may further comprise a body attachable to a said pin or wire, for retaining said illumination means to said orthopaedic pin or wire.

[0022] Said body preferably comprises a passage or channel into which said orthopaedic pin or wire may be located.

[0023] Said passage or channel is preferably adapted to closely fit around said orthopaedic pin or wire such that said body self retains to said orthopaedic pin or wire at a fixed location along said pin or wire; and such that under manual pressure exerted by a person’s fingers, said pin or wire may be slid axially along said passage, thereby allowing a position of said body along said passage to be adjusted.

[0024] Said body may comprise a slot which extends laterally in said body in a direction transverse to a main axial direction of said passage or channel.

[0025] Preferably said body is formed of a resiliently deformable material.

[0026] Said body may comprise a stud portion having larger thickness dimension at a position nearer the centre of said body, and at a position radially further away from said centre of said body, said slot being dimensions suitable for passage of a said orthopaedic pin or wire.

-6[0027] Said device may comprise a tubular shroud member having a chamber which in use is arranged to be illuminated by said ultraviolet light source.

[0028] Said shroud member preferably comprises a tubular cylindrical member.

[0029] Said shroud member is preferably configured to attach to said orthopaedic wire or pin, either directly or indirectly.

[0030] Said shroud member may be configured to attach to said body.

[0031] Said shroud member may comprise a tubular substantially circular cylindrical member having a closed upper end;

said upper end having a peripheral annular shelf in which said body member locates, so as to retain said body member substantially centrally coaxially with respect to said shroud member.

[0032] Said shroud member may comprise a resiliently biased foam plastics, latex rubber, synthetic rubber or gel like materials.

[0033] The device may comprise a camera directed to have its field of view coincident with a region around said pin or wire, enabling viewing of the pin site.

[0034] The device may comprise a wired or wireless transmitter in communication with said camera, for wirelessly transmission of the images captured by said camera to a remote receiver.

[0035] The device may further comprise a visible light illumination means for illuminating a field of view of said camera.

[0036] The camera may also ensure that there is no light leakage and checks the seal of the foam cover. This ensures the foam is still sealing the leg against debris. The camera image may show any debris present within the wound

-7that might need mechanically cleaning away. Finally, the camera, may be used to prevent cleaning from occurring if there are any light leakages; UVC can be damaging to eyesight if view directly, so it is important to prevent direct viewing of the UVC source by patient if the system is not fully covered and to ensure that UVC light cannot leak from the enclosed pin site. Said ultraviolet illumination means may be attached to an orthopaedic pin or wire such that it cannot be detached from said orthopaedic pin or wire without the use of a special tool designed specifically for the purpose of removing the ultraviolet illumination means from the pin or K-wire.

[0037] In a further aspect, there is provided an attachment for an orthopaedic wire, comprising an ultraviolet light guide for guiding ultraviolet light along said orthopaedic wire.

[0038] The invention includes a device for illuminating an insertion site of an orthopaedic wire or pin, said device comprising:

an ultraviolet light source; and means for attaching said ultraviolet light source to a said orthopaedic wire or pin.

[0039] The embodiments include a device which is attachable to an orthopaedic pin or wire, said device comprising:

a substantially flat disc -shaped body, said body comprising:

a central aperture or passage into which a said orthopaedic pin or wire may locate;

a slot extending from said radially extending aperture or passage in a direction transverse to a main axis direction of said aperture or passage; and

-8one or a plurality of ultraviolet light emitting diodes positioned on the surface of said body, said one or plurality of light emitting diodes positioned to emit one or more beams of ultraviolet light in a direction substantially parallel to a main axis direction of said aperture or passage.

[0040] The embodiments include a device which is attachable to an orthopaedic pin or wire, said device comprising:

a substantially flat body, said body comprising a central aperture or passage into which a said orthopaedic pin or wire may locate;

said body extending laterally in a direction transverse to a main axis direction of said aperture or passage;

a slot or channel extending from said radially extending aperture or passage in a direction transverse to a main axis direction of said aperture or passage;

one or a plurality of ultraviolet light emitting diodes positioned on the surface of said body, said one or plurality of light emitting diodes positioned to emit one or more beams of ultraviolet light in a direction substantially parallel to a main axis direction of said aperture or passage; and at least one camera device mounted on said body, said camera device having a field of view coincident with a region illuminated by said one or plurality of ultraviolet light emitting diodes.

[0041] The invention includes an apparatus for monitoring pin site infection of one or a plurality of orthopaedic pins or wires, said apparatus comprising:

at least one camera capable of generating electronic image data;

-9means for attaching said camera to a said orthopaedic pin or wire; and a transmitter for (wired or wirelessly) transmitting said image data of images captured by said camera.

[0042] The apparatus preferably further comprises a receiver device for receiving said wirelessly transmitted image data.

[0043] The apparatus preferably further comprises a visual display device for displaying images captured by a said camera.

[0044] Each pin site may have attached its own camera device and each of a plurality of camera devices may use corresponding respective plurality of cameras on a plurality of wires or pins on the same patient may use a common transmitter to transmit image data from each camera to a remote receiving device, so as to enable a healthcare professional to remotely view one or a plurality of pin sites of a patient, for example over the Internet or over a virtual private network.

[0045] Machine learning or other artificial intelligence systems may be used to assist with pre-filtering of the capture images. Looking to early signs of infection, foreign bodies within the wound or skin damaged caused by over use of the system. Any anomalous results may be automatically alerted to a human clinician for further investigation or action, for example by means of an electronic message, an on-screen message, or a screen “push” view which automatically pops up on a monitoring screen.

[0046] Other aspects are as set out in the claims herein.

Brief Description of the Drawings [0047] For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which:

-10Figure 1 herein illustrates schematically in perspective view, four individual Kirschner wires fitted around a patient’s thigh extending substantially radially outwardly of the femur, through the patient’s muscle, and through the patient’s skin;

Figure 2 herein illustrates schematically in cut away view an individual K wire fitted into a section of bone;

Figure 3 herein, shows in perspective view a first illumination device for illuminating a region around an orthopaedic wire according to a first specific embodiment;

Figure 4 herein shows the first illumination device in view from above;

Figure 5 herein shows the first illumination device in combination with a foam protection pad in cut away view;

Figure 6 herein shows in external perspective view a second illumination device according to a second specific embodiment, comprising one or more UVC light sources and an optical viewing device;

Figure 7 herein illustrates schematically the second illumination device in partial view from underneath;

Figure 8 herein illustrates schematically communication between the second illumination device, a local transmitter, a receiver and a monitoring device;

Figure 9 herein illustrates schematically a main monitoring station for monitoring a plurality of remote patient monitoring apparatus as shown in figure 8 herein;

-11Figure 10 herein illustrates schematically a third illumination device according to a third specific embodiment, comprising a UVC light guide located externally around an orthopaedic pin or wire; and

Figure 11 herein illustrates schematically a fourth illumination device according to a fourth specific embodiment, comprising a UVC light guide and one or more UVC light translucent or transparent light scattering sections.

Detailed Description of the Embodiments [0048] There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the description.

[0049] In the present specification, the terms “orthopaedic wire”, “orthopaedic pin”, Kirschner wire” and “k - Wire” are used interchangeably to denote a rigid elongate member which is designed to secure into a section of a patient’s bone, and which extends in a direction radially outward of said bone through soft tissue surrounding the bone. A proximal end of the member may be secured to an external frame outside the patient’s body, and a distal end of the member is secured in said bone or pass through it, such that the member passes through soft tissue between said bone and a patient’s external body surface.

[0050] Specific embodiments disclosed herein apply the use of ultraviolet light (UV light) to orthopaedic wires or pins to reduce or alleviate infection of a pin tract site at which a pin or wire enters into a patient’s tissue. Ultraviolet light covers a wavelength spectrum from 100nm to 380nm and is subdivided into three regions by wavelength: UVA (320 to 400 nm), UVB (280 to 320 nm), and UVC (200 to 280 nm). UVC has the strongest germicidal effect.

-12[0051] Referring to figures 3 and 4 herein, there is illustrated schematically an orthopaedic Kirchner wire 300 fitted with a first illumination device according to the first specific embodiment.

[0052] The first illumination device 301 comprises a body 302 having an upper substantially planar circular surface 303; a lower substantially planar surface 304; a coaxially centrally located stud portion 305 having a cylindrical part circular passage there - through, said passage extending in a direction which lies across a main plane occupied by the body, and in a direction transverse to the main axial direction of the central channel or passage, so that the body extends radially outwards from the central passage; a radially extending slot 306 of dimensions which enable the body of the device to be pushed over the orthopaedic wire in a direction either transverse to the main length axis wire, or in a twist fit over the wire so that in use, the body is self-retaining on the orthopaedic wire; and on the lower surface of the body there are provided one or a plurality of UV-C light emitting devices, preferably UV-C light emitting diodes 307 - 309.

[0053] The dimensions of the slot passage 306 are such that the orthopaedic wire can fit through the slot passage under the application of moderate force sufficient as to be applied relatively easily by the fingers of a surgeon or other health personnel, so that the orthopaedic wire can be located with central passage in the stud portion 305. The dimensions of the central passage are such that the orthopaedic wire can fit as a push - fit over the wire, such that the central part of the body clips on to the wire, and such that once fitted, the body is self - attaching to the wire by friction between the walls of the passage and the outer surface of the K wire without the need for any glue or other components but also the fit of the body to the orthopaedic wire is such that the attachment device can be slid along the wire in the main axial length direction of the wire so as to adjust the position of the body along the length of the orthopaedic wire.

[0054] Preferably the body portion is made of a rigid or semi rigid plastics material, having enough flexibility and resilience to enable the body to firmly secured to the wire in a “clip” or “snap on” action, and also so as to allow the

-13attachment device to be pulled off the wire by hand, without the use of tools. The material is resiliently deformable to allow the coin or disc -shaped body to be pushed over the K-wire so that the K-wire can be inserted in to the central circular cylindrical passage, and such that the body retains itself to the same axial position of the K-wire once fitted. Once fitted, the dimensions of the central passage through the body are such that there is enough friction between the material of the body and the K wire to securely locate the body in a fixed position along the length of the wire, but so that friction can easily be overcome by force of the human hand so as to slide the body up and down along the length of the K wire. Once released, the body stays in place without being so loose as to slide along the K wire without application of further force.

[0055] The device is attachable to a K-wire using only the force applied by surgeons fingers, and similarly can be detached from the K-wire using only finger pressure and without the use of any additional tools or instruments.

[0056] In the embodiment shown, the support body comprises a flat circular coin -shaped disc having a radially extending slot. The centrally located stud portion has a larger thickness dimension in the direction axially along the central channel or passage at a position nearer the centre of said body, than does the remainder of the disc or coin -shaped body at positions radially further away from said centre of said body.

[0057] In the first embodiment shown, the IIV-C emitting light emitting diodes (LED’s) are commercially available and emit ultraviolet light in the wavelength range 255nm to 280nm, with the specific peak wavelength being selectable within that range by selecting the composition of the semiconductor materials used to fabricate the diodes. The light-emitting diodes are arranged on the underside of the body such that they shine their ultraviolet - C light along the length of the K - wire and onto the surface of the skin at and around the entry point of the K - wire into the body, thereby illuminating the point of entry of the wire or pin, and the region immediately surrounding the pin or wire entry point.

-14[0058] The optimum dimensions of the body are a matter of design, but are determined by the ergonomics of ease of fitment to the K - wires. The body must therefore be large enough to manipulate using an adult human’s fingers, wearing surgical gloves and the resilience and stiffness of the material of the body should be selected such that an adult surgeon can clip and unclip the body to a K - wire using a finger and thumb so that the device can preferably be fitted using a single hand, leaving the surgeon’s other hand free for use.

[0059] In the best mode embodiment, typically a circular body having a diameter in the range 18mm to 30mm is suitable.

[0060] The UVC light illumination beam pattern is determined by the beam angle of the individual light-emitting diodes used. The output beam angle of each light-emitting diode may be pre - selected by the fitment of an output lens on each diode at the point of manufacture which gives the optimised beam angle.

[0061] Taking the definition of beam angle as being the angle between the positions of the emitted beam which are 0.5 times the maximum intensity I of the beam, a beam angle of around 30° is preferred. The radiation intensity for optimum results depends upon the clinical application. Typically, radiation densities in the rangel pW/cm² to 8 pW/cm² may be used.

[0062] To obtain a sufficiently uniform and sufficiently intense illumination of an area around the pin or wire, there is preferably a plurality of light-emitting diodes arranged on the underside of the body, spaced apart from the central passage. The plurality of light-emitting diodes may be arranged in a ring around the underside of the body and anywhere between 2 and 10 individual lightemitting diodes are provided, the exact number being determined by the intensity of illumination required, and space considerations.

[0063] Power supplied to the plurality of light-emitting diodes is provided by an electric wire 310 which may run parallel to the K - wire or which can be wrapped around the K wire in a spiral and attached to a battery power supply unit which can be secured to the external frame. The battery supply unit need not be large, and depending upon the application may use rechargeable batteries such

-15as lithium-ion, or in more compact embodiments the UVC light source may be powered by button type batteries attached to the body. Finally, energy may be harvested from the body of the patient (via movement or heat) or other renewable sources such as solar power to “top-up” the batteries charge during use.

[0064] In use, after fitting a K - wire in situ, and attachment device may be fitted to the K wire by surgeon by simply clipping the body portion to the K wire and sliding the body axially along the length of the K wire to the desired height above the skin surface.

[0065] Referring to figure 5 herein, the first illumination device is shown in combination with a tubular circular cylindrical foam shroud 500. The shroud comprises a UVC light opaque flexible soft plastic, rubber or gel resiliently deformable foam material having a tubular circular cylindrical wall. The wall has at a lower end a substantially flat annular surface which, in use, rests upon the skin of a patient making contact there with; at an upper end, an upper substantially annular end wall into which the circular disc -shaped body of the attachment device fits. The upper end may be stepped slightly so as to centrally locate the circular disc like body of the attachment device, said upper end having a peripheral annular shelf in which said body member locates, so as to retain said body member and said K wire substantially centrally coaxially with respect to said shroud member.

[0066] In use, the circular foam shroud performs two functions. Firstly, the shroud performs a physical barrier around the pin insertion site, enclosing the pin insertion site and preventing ingress of dirt around the pin tract, and secondly, to form a cavity which is bathed in UVC light emitted from the light-emitting diodes.

[0067] In order to perform this function, there must be slight pressure to compress the tubular foam cylinder between the body of the attachment device and the surface of the patient’s skin around pin insertion site. The resilience of the foam needs to be selected to ensure continuous contact between the skin surface and the lower end of the foam shroud.

-16[0068] The foam shroud may be retained between the body 301 and the patient’s skin by virtue of compression between the body 301 device and the skin surface, in which case the upper end of the shroud may be located to the illumination device by virtue of compression between the circular disc -shaped body in a circular recess at the upper end of the shroud, or alternatively the upper end of the shroud may be secured to the periphery or rim region of the body 301 by adhesive.

[0069] Alternatively , the shroud may be cut to from an extruded “C” shaped tube, that can then be fitted around the pin and closed with an adhesive or temporary fixings such as Velcro, magnetic closures, press-studs or made from a material sufficiently stiff and elastic that it elastically snaps closed [0070] Alternatively, instead of resting against the surface of the skin, the lower end of the foam shroud may comprise an adhesive which sticks the lower flat annular surface of the shroud to the skin surface.

[0071] In use, the circular cylindrical shroud may be fitted over the end of the K - wire which is external to the body, before attaching the body 301 to the K - wire, and then sliding the body 301 along the K wire so as to locate the tubular shroud member between the body and the patient’s skin surface.

[0072] The dimensions of the tubular circular cylindrical shroud may vary depending upon the size of the K wires and the application. The following shroud dimensions are preferred ranges:

[0073] Height: range 10mm to 30mm [0074] Inner diameter: range 6mm to 18mm;

[0075] Outer diameter: range 12mm to 24mm [0076] Wall thickness in radial direction: range 2mm to 10mm [0077] Preferably, the light-emitting diodes fitted to the underside of the body are fitted at a radial distance from the main central axis of the body which is

-17within the radial distance of the central circular cylindrical cavity formed by the foam shroud.

[0078] Referring to figure 6 herein, there is illustrated schematically in perspective view, a second illumination device 600 together with a foam plastics shroud 601 as hereinbefore described with reference to the first illumination device.

[0079] The second illumination device 600 comprises all of the features described herein above in relation to the first illumination device, but with the addition of a camera 602 fitted to the underside of the body as shown in figure 7 herein. Preferably the camera is a small charge-coupled delay (cod) camera device having high-resolution, but could be any other camera type which fits in the available space.

[0080] The second illumination device is attachable to an orthopaedic pin or wire and comprises a substantially flat disc - shaped body 603, said body comprising a cylindrical part circular central aperture or passage 605 into which a said orthopaedic pin or wire may locate, the relative dimensions of the aperture or passage to the outer diameter of the pin or wire being such that the body is selfretaining to said pin or wire but can be slid along said pin or wire by the application of manual pressure from a surgeon’s fingers; said body extending laterally in a direction transverse to a main axis direction of said passage; a slot or channel extending from said radially extending slot or passage in a direction transverse to a main axis direction of said slot or passage, said slot being of dimensions such that the pin or wire may pass through said slot either with no resistance, or with slight resistance which can be overcome by exertion of pressure from a human hand; one or a plurality of ultraviolet light emitting diodes 606 positioned on the lower surface of said body, which in use is held on the orthopaedic pin or wire and is spaced apart from a position of entry of the pin or wire into a patient’s body; said one or plurality of light emitting diodes being positioned to emit one or more beams of ultraviolet light in a direction substantially parallel to a main axis direction of said slot or passage; and at least one micro-camera device 602 mounted on

-18said body, said camera device having a field of view coincident with a region illuminated by said one or plurality of ultraviolet light emitting diodes.

[0081] The light-emitting diodes 606 and the camera device 602 may draw power from a small battery mounted on the opposite side of the body, or alternatively may draw power from a separate electrical power supply wire which can be wound around the orthopaedic pin or wire.

[0082] There may be provided a small dimension transmitter or transceiver mounted on the body including an integrated circuit for converting signals from the camera device into a format which can be wirelessly transmitted by the transmitter via a wired or ideally wireless method to a remote receiving device using Wi-Fi, LiFi, Bluetooth, XBee or other suitable short range transmission protocol.

[0083] The integrated circuit may comprise an interface for interfacing with a mobile phone GPRS, 3G, 4G or 5G communication system for sending and receiving data via a mobile phone or like device equipped with GPRS, 3G, 4G, or 5G protocols and communications capabilities. The use of a mobile phone or mobile tablet device so equipped may allow the patient to be active when the illumination devices are in use, and at the same time maintain remote monitoring and reporting of data to a remote location.

[0084] The camera device may be of a low voltage type, such as used in handheld cameras or mobile phone cameras, or may be a medical type micro camera, for example as used in endoscopy.

[0085] In the case of a medical type camera, performance characteristics may be as follows:

Parameter	Camera 1	Camera 2
Outer diameter 1 dimension	1.2mm	3.0mm x 3.0mm
Length (including optics)	5mm	15 mm

Longitudinal resolution	220px	500px
Lateral resolution	224px	582px
Effective elements		291,000 px
Sensor resolution	49,280 px
Pixel size	2.2pm x 2.2pm	2.95pm x 1,90pm
Image area	493pm x 488pm
Cable diameter	0.58 mm
Cable length	2m
Frame rate	30 frames / s	30 frames / s
Field of view	1007130°	140°
Depth of field	5-50mm /2 - 6mm	5mm - 100mm
Sensor type	CMOS	CCD
Scan mode	Progressive	interlaced
Working distance	10mm / 3.5mm	20mm
Colour mosaic	RGB Bayer pattern	Ye, Cy, Mg, G
Video output	HDMI

[0086] Referring to figure 7 herein, there is illustrated schematically in view from underneath the body of the second attachment device. The body comprises 5 a substantially circular disc 603 having moulded integrally therewith, a centrally located circular cylindrical stud portion 604 having a central passage 605 through which a K-wire 607 may be inserted.

[0087] A plurality of ultraviolet light emitting device 606, preferably UVC light-emitting diodes, are arranged in a ring around the central passage 605, and having their light beams directed in a direction across a main plane of the disc shaped body 603.

[0088] Similarly to the first embodiment described herein, the light-emitting 15 diodes illuminate the region immediately underneath the underside of the central disc -shaped body. Further, a field of view of the camera 602 overlaps with the illuminated region directly underneath the area of the disc-shaped body 603.

-20[0089] The shroud material may be substantially opaque in the ultraviolet range, but transparent or translucent in the visible range to allow visible light into the cavity, so that the camera can detect an image of the surface skin immediately around the pin tract entry point. Alternatively, the shroud may be of a visually opaque material, in which case a further visible range light-emitting diode may be fitted to the underside of the body of the attachment device to illuminate the interior of the cavity formed by the shroud and the skin surface in the vicinity around the pin entry point to the body with visible light.

[0090] The second embodiment may comprise a slot in the disc -shaped body 603, and in the stud 604, through which the K wire may pass in order to locate a Kwire in a central part cylindrical passage in a twist fit action substantially as described herein before with reference to the first embodiment.

[0091] In a variation of the second embodiment, the slot may be omitted and the illumination device may be slid over the proximal protruding end of K-wire for fitment onto the K wire.

[0092] Referring to figure 8 herein, there is illustrated schematically in cutaway view, the second embodiment illumination device in situ on a K wire 607 secured into a patient’s limb, incorporated as part of a pin site monitoring apparatus.

[0093] A distal end of the K wire 607 is secured into a patient’s bone 800. The attachment device 600 is attached to the K wire 607 and is positioned at a distance away from the skin surface 801 such that the shroud member 601 presses against the skin surface to make close enough contact to keep dirt away from the pin tract region.

[0094] The second attachment device comprises a micro camera device 602, and one or more ultraviolet light-emitting diode 603 which are wired to a transmitter/receiver device 6802 on the body of the attachment device. The transmitter/receiver device is preferably a Wi-Fi, Bluetooth or similar

-21transmitter/receiver but may be a transmitter only. Signals from the video camera 602 are transmitted in real time to a corresponding remote transmitter/receiver and digital image processing device 803 which sends an output to a monitoring device 804, for example a computer device, comprising a video display. This allows remote monitoring of the image captured by the digital camera 602 in realtime from a remote location.

[0095] It will be appreciated by those skilled in the art that the connection between the transmitter/receiver and image processing unit 803 and the computer with monitor 804 may be made over a virtual private network (VPN) or over the Internet. Hence, the monitoring data processing unit 803 may be provided locally to the patient, within range of Wi-Fi or Bluetooth signals for example in the same room, whilst the monitoring unit 804 may be hardwired direct to the image processing and monitoring unit 803 and located within a few metres of it, or the computer monitoring device and visual display 804 may be many miles remote from the monitoring and image processing device 803 which is within a relatively short range of a few metres of the camera devices.

[0096] Referring to figure 9 herein, there is illustrated schematically communication between a plurality of remote monitoring stations 803, 804 and a main control and processing centre 901, 902 over the Internet.

[0097] Where connection between the transmitter/receiver and image processing unit and the remote monitoring unit 804 is made over the Internet, this enables healthcare professionals at a hospital or other location to monitor in realtime video images of pin insertion sites on a patient who may be at home several miles away from the hospital or other monitoring location.

[0098] A machine learning I or artificial intelligence (Al) system may be used to pre-vet, pre - process or pre - filter images of pin entry sites received from the camera system to reduce the need for the clinician to visually examine every pin-site picture. The machine learning or artificial intelligence system may be configured to highlight those images in need of further investigation by a human.

-22[0099] In further embodiments, controlling and administering the UVC light cleaning or even the prescribing of antibiotic treatment at the pin site may be performed autonomously by a machine learning or Al system.

[0100] A plurality of individual attachment devices may communicate with a single transmitter/Zreceiver and video image processing unit 803 so that a plurality of pin tract sites can be monitored simultaneously, using one or a plurality of video monitoring screens. Using a single video monitoring screen, the area of the screen may be divided up into a number of discrete areas, each separate discrete area corresponding to a view of a separate pin entry site for a patient.

[0101] In the best mode, the image surveillance facility using the cameras near to the pin site also has UVC illumination to reduce infection. However in principle the monitoring apparatus need not also have light-emitting diodes for UVC illumination of the pin site, but can provide pin site monitoring only.

[0102] Referring to figure 10 herein, there is illustrated schematically a third illumination device for attaching to an orthopaedic wire or pin 1000, according to a third specific embodiment.

[0103] The third illumination device comprises a light guide 1001 preferably in the form of a flexible fibre-optic cable capable of carrying ultraviolet light, particularly exclusively UVC light. The flexible fibre-optic cable is wrapped around the outside of the orthopaedic wire in a spiral manner. A proximal end of the fibreoptic cable is connected to a UVC light-emitting diode, via a fish eye type micro lens which focuses the output of the light-emitting diode into the end of the fibreoptic cable. Light is transmitted down the fibre-optic cable and spirally down or along the length of the K-wire to which the fibre-optic cable is securely attached.

[0104] The K-wire may be inserted into the patient’s soft tissue, piercing the skin, such that the fibre-optic cable also enters the soft tissue and resides within the pin tract. The fibre-optic cable may extend along the K-wire, as far as the sharp distal cutting end of the K wire, so that the fibre-optic cable can transmit light

-23all the way through the soft tissue, down to the point where the K wire enters the bone.

[0105] The fibre-optic cable is selected so as to be lossy enough that sufficient ultraviolet light scatters from the central core of the fibre-optic cable to emit ultraviolet light along the length of the fibre-optic cable. This can be achieved by doping the central core of the fibre-optic cable with elements which cause UV scattering so that light leaks out of the sides of the central core and is emitted out of the fibre-optic cable. The intensity and proportion of transmitted light per unit length of fibre optic cable which leaks from the central core of the fibre-optic cable can be selected as a design parameter by selecting the doping element and concentrations of doping in the fibre-optic cable core.

[0106] Using the third embodiment illumination device, UVC light can be delivered along the length of the K wire to locations both outside and inside the body, down to the distal end of the K wire at a position where the K wire is secured to the bone.

[0107] Also shown in figure 10 is an external resilient foam shroud member 1002 which may be slid along the length of the K wire and over the externally wound fibre-optic cable and which acts as a dressing to prevent dirt ingress around the region where the K wire enters the skin of the patient. Preferably the foam shroud comprises a sterilisable soft resiliently deformable foam plastics material. The shroud may be made of a thermoplastic material which is opaque to ultraviolet light.

[0108] Referring to figure 11 herein, there is illustrated schematically in partial cutaway view from one side a fourth illumination device 1100 according to a fourth specific embodiment, in the form of an external light guide which surrounds an orthopaedic wire 1101.

[0108] A conventional orthopaedic wire 1101, for example formed of heavy gauge stainless steel or titanium alloy wire is surrounded by a transparent circular cylindrical light guide 1002. The light guide may comprise a glass or plastics tube

-24which can be slid over the orthopaedic K-wire after insertion of the K-wire into the patient’s body.

[0109] Along the length of the cylindrical tube there are provided one or a plurality of tubular circular cylindrical plastics or glass light scattering regions 1103 having a different refractive index to the refractive index of the cylindrical transparent light guide tube 1102. Ultraviolet light is focused into the circular cylindrical tubular light guide at a distal end using an ultraviolet light source and a focusing lens. Light travels along the tubular light guide around the outside of the orthopaedic wire and is scattered by the one or plurality of scattering regions or components 1103 such that light is emitted substantially radially outwardly from the K-wire into the surrounding pin tract region and UV light is directed away from a main central axis of the cylindrical tube and away from the main central axis of the K-wire.

[0110] The one or plurality of tubular circular cylindrical scattering regions 1103 may contain scattering elements, such as individual microscopic flecks or specs of reflective material in order to divert light from its path within the tubular circular cylindrical light guide out of the cylindrical outer surface of the light guide and away from the K-wire or pin into the surrounding tissue region, at locations where the light guide is within the pin tract between the patient’s skin and the bone to which the end of K-wire or pin may be anchored.

[0111] In use, the fourth embodiment illumination device may be inserted over the K wire, to a depth all the way down to the distal end of the K-wire where the K-wire is secured into the patient’s bone, so that UV light can be delivered all the way down the pin tract. UV light may therefore be delivered both on the surface of the skin where the K-wire penetrates a subject’s skin, and inside a passage in the subject’s body between the outer surface of the skin and the bone, thereby reducing the likelihood of infection within the pin tract.

[0112] Alternatively, the light guide can be fitted over the K-wire only to the position where the end of the light guide is in contact with or slightly above the pin

-25entry point to the patient’s body so as to illuminate the immediate external region around the entry point of the orthopaedic pin into the patient’s body.

[0113] By varying the distance of the light guide along the K wire, relative to the sharp penetrating end of the K wire, as a design parameter of the illumination device, the depth of penetration of the light guide into the patient’s body can be selected.

[0114] The length distance along the pin or K-wire along which the light guide extends can be selected as a design parameter and the absolute distance along which the light guide extends will vary depending upon the size and dimensions of the K-wire, and its application. Relatively larger K-wires for large limbs such as a femur may have the light guide extending by distance of up to 15 cm in the main axial direction of the K-wire, whereas smaller K-wires for smaller subjects may have a correspondingly smaller distance over which the light guide extends. In general, the light guide will extend over a distance on the K-wire which is embedded within the subject’s body, but excluding the sharp tip of the K-wire which may be pointed and threaded, for drilling and securing into the bone. For the distance of K-wire extending from a position within a few millimetres from the bone itself, through the subject’s flesh and to the skin surface, the light guide may extend over this length section of the K-wire, as well as extending externally of the patient’s skin. As measured in terms of the radius of the K-wire, the light guide may extend along a length of the K-wire for a distance corresponding to 2 to 150 times the radius of the K-wire, and preferably for a distance corresponding to 10 to 80 times the radius of the K-wire in best mode embodiments.

[0115] Direct viewing of UVC light by a patient or health professional may prevent dangerous to eye sight. In a further embodiment, or as modifications to the embodiments described herein above, fitment of the illumination device to a pin or K-wire may be restricted such that it requires the use of special tools, and so that the illumination device cannot be fitted to or removed from a pin or K-wire without those special tools. This may prevent the inadvertent direct viewing of the UVC light by a patient viewing the device without UVC filtering goggles or glasses.

-26[0116] Each of the first to fourth embodiments described herein above may include all of the features of those respective embodiments, and in addition a connecting clip or other attachment which connects the UVC illumination device to a pin or K-wire, such attachment being adapted so that once fitted to the pin or Kwire, it can only be removed by the use of a bespoke designed tool, designed to unclip or detach the attachment or connecting clip from the pin or K-wire.

[0117] In yet a further embodiment or a variation or modification to an one of the embodiments described herein above, a safety feature may be added to the illumination device comprising a control circuit to the UVC light-emitting diode which only activates the UVC light-emitting diode to an ON condition when a camera can view the pin to which the illumination device is attached, and a portion of the patient’s skin around the pin entry site. In circumstances where the view is obscured or a clear image of the pin and pin entry site cannot be viewed, as measured either by a remote monitoring station as described herein, or by a machine learning or artificial intelligence program, then the UVC light-emitting diode is disabled to an OFF condition. Hence, if for any reason the UVC illumination device becomes detached from a pin or K-wire and therefore is no longer viewable by the camera, then the UVC light source is turned off as a default failsafe safety feature. The remote monitoring apparatus monitors each individual pin site of the one or plurality of the pin sites, and for any pin site for which a clear image of said pin site is not available, the monitoring apparatus automatically operates to disable the corresponding respective ultraviolet light emitting means associated with that pin site.

[0118] Whilst various embodiments herein have been described in the context of an orthopaedic Kirschner wire or K wire, in other applications, the embodiments may be applied to other substantially cylindrical medically intrusive devices which are designed to be inserted from a position outside the patient’s body, having a portion which is inserted into the patient’s body, such as for example a cannula; a syringe; a drip fluid line insertion; a cannulated fixation screw for percutaneous fixation of a scaphoid fracture; or a blood fluid line insertion.

-27[0119] The embodiments disclosed herein may be designed and engineered as single use disposable devices, or may be designed and engineered to be sterilisable for repeated use in an autoclave.

[0120] Unless specifically stated, or unless technically infeasible, any individual technical feature of any embodiment described herein above may be combined with or added to any other specific embodiment described herein.

Claims

1. A device for illuminating an insertion site of an orthopaedic pin or wire, said device comprising:

an ultraviolet illumination means for illuminating of said orthopaedic pin or wire and a region of a patient’s body immediately adjacent said pin or wire with ultra violet light, said ultraviolet illumination means being attachable to said orthopaedic pin or wire;

said illumination means comprising a light guide extending along a length of said orthopaedic pin or wire.

2. The device as claimed in claim 1, wherein said illumination means comprises one or a plurality of ultra violet light emitting diodes.

3. The device as claimed in claim 1 or 2, wherein said illumination means comprises an ultraviolet light guide.

4. The device as claimed in claim 3, wherein said light guide extends along said orthopaedic pin or wire close to a distal end of said pin or wire which in use, is secured in a subject’s bone.

5. The device as claimed in claim 3 or 4, wherein said ultraviolet light guide comprises a tubular light guide which fits around said orthopaedic pin or wire.

6. The device as claimed in claim 5, wherein said tubular light guide comprises one or a plurality of light scattering regions for directing light out of said light guide in a direction away from a main central axis of said light guide.

7. The device as claimed in any one of the preceding claims, wherein said light guide comprises a fibre-optic cable.

8. The device as claimed in any one of the preceding claims, further comprising a body attachable to a said pin or wire, for retaining said illumination means to said orthopaedic pin or wire.

9. The device as claimed in claim 8 wherein said body comprises a passage or channel into which said orthopaedic pin or wire may be slid on to said body.

10. The device as claimed in claim 9, wherein said passage or channel is adapted to closely fit around said orthopaedic pin or wire such that said body self retains to said orthopaedic pin or wire at a fixed location along said pin or wire; and such that under manual pressure exerted by a person’s fingers, said pin or wire may be slid axially along said passage, thereby allowing a position of said body along said passage to be adjusted.

11. The device as claimed in claim 8, wherein said body comprises a slot which extends laterally in said body in a direction transverse to a main axial direction of said passage or channel.

12. The device as claimed in any one of claims 8 to 11 wherein said body is formed of a resiliently deformable material.

13. The device as claimed in any one of the preceding claims, further comprising a tubular shroud member having a chamber which in use is arranged to be illuminated by said ultraviolet light source.

14. The device as claimed in claim 13 wherein said shroud member comprises a tubular cylindrical member.

15. The device as claimed in claim 13 or 14 wherein said shroud member is configured to attach to said orthopaedic wire or pin either directly or indirectly.

-SO-

16. The device as claimed in any one of claims 13 to 15 as appendant to claim 8, wherein said shroud member comprises a tubular substantially circular cylindrical member having a closed upper end;

17. The device as claimed in any one of claims 13 to 16 wherein said shroud member comprises a resilient foam plastics material.

18. The device as claimed in any one of the preceding claims further comprising a camera directed to have its field of view coincident with a region around said pin or wire.

19. The device as claimed in claim 18, further comprising a transmitter in communication with said camera, transmitting images captured by said camera to a remote receiver.

20. The device as claimed in any one of the preceding claims, further comprising a visible light illumination means for illuminating a field of view of said camera.

21. The device as claimed in any one of the preceding claims, wherein said ultraviolet illumination means is attached to said orthopaedic pin or wire such that it cannot be detached from said orthopaedic pin or wire without the use of a tool.

22. An apparatus for monitoring pin site infection of one or a plurality of orthopaedic pins or wires, said apparatus comprising:

at least one camera;

means for attaching said camera to a said orthopaedic pin or wire; and

-31a transmitter for wirelessly transmitting image data of images captured by said camera.

23. The apparatus as claimed in claim 22, further comprising:

a receiver device for receiving said wireless transmitted image data; and a visual display device for displaying images captured by said camera.

24. The apparatus as claimed in claim 22 or 23, further comprising a remote monitoring apparatus for monitoring one or a plurality of pin site images derived from said transmitted image data.

25. The apparatus as claimed in any one of claims 22 to 24, further comprising one or more ultraviolet light emitting means attachable to one or more said orthopaedic pins or wires.