WO1988000477A1

WO1988000477A1 - Injection needle sheath

Info

Publication number: WO1988000477A1
Application number: PCT/GB1987/000422
Authority: WO
Inventors: Alan Arthur Quayle; Ann Quayle; Emma Quayle
Original assignee: The Victoria University Of Manchester
Priority date: 1986-07-22
Filing date: 1987-06-17
Publication date: 1988-01-28
Also published as: GB8617853D0; AU7587587A

Abstract

A sheath (39) for a needle (24) such as a hypodermic needle or acupuncture needle, reduces or eliminates the possibility of self-impalement by having a longitudinally extending entry (40) into which a needle (24) can be introduced, after use or between uses, with a movement of which at least a major portion is transverse of the needle axis. This reduces the chance of self-impalement, and when used in a method of the invention, supporting the sheath assembly manually adjacent its open end allows the sheathing movement to be carried out with the needle point spaced well away from the user's fingers (62, 63).

Description

Injection needle sheath.

This invention relates to needle assemblies for making injections for medical, dental, veterinary, acupuncture and comparable purposes. 5« A commonly used know needle assembly for medical use comprises a hub from one end of which projects a hollow needle and whose other end forms a frusto-conical socket for engagement with a complementary spigot on a syringe. A sheath completes the assembly and is generally tubular being

10. closed at one end and shaped to engage the hub at its other end. The assembly is supplied with the needle within the sheath and the needle maintained in an enclosure formed by the hub and sheath. It is common practice for the needle after use, to be inserted back into the sheath to protect

15. personnel against further contact with a possibly contaminated needle or injury thereby. Unfortunately, the act of re-sheathing (Fig. 3), involving the transport of a needle towards a hand-held sheath is intrinsically dangerous because in a number of re-sheathings a person will undoubtedly

20. eventually miss the sheath and stick a finger or thumb.

Self-injection with a harmful organism or substance can have serious, even fatal, effects on medical staff, and the danger is felt to be so great (for medical staff performing perhaps tens of injections per week) that re-sheathing is often

25. discouraged by administrators. This practice could lead to the possible injury of others later when the discarded needle must be dumped or transferred to some final receptacle.

In dentistry an assembly 10 (Figs. 1 and 3) is used which includes a hub 11, a longer, (tissue piercing) needle 5. part 12, a shorter (drug-capsule-piercing) needle part 13 and respective sheaths 15 and 16. In use of this needle assembly 10, the user should be prevented from self-injection when re-sheathing each needle part.

It is an object of the present invention to provide a 10. needle assembly by which the possibility of self-impalement is reduced or obviated.

Accordingly the invention provides a needle assembly including a hub, a needle and a sheath, the sheath having a longitudinal entry whereby a needle, after use, can be 15. introduced into the sheath by a movement transverse to its length.

In an assembly as aforesaid the sheath can initially surround the needle which is removed therefrom for use and, after use is re-introduced into the sheath prior to disposal. 20. However, the sheath need not initially surround the needle but can serve solely as a receptacle for a used needle.

The invention further provides a needle receptacle having an elongate entry and into which a needle can be 25. introduced by movement of the needle in a direction transversely of its longitudinal axis.

The entry can be a slit or slot in side walling of the sheath or receptacle. The entry can be initially closed by a frangible or removable member or a tear strip 5. or by a displaceable flange or the like.

Alternatively the entry can be a line of weakness converted to be an entry by manipulation of the receptacle or by operation of a pull-string or the like.

In the case of a double-ended needle assembly, such 10. as a dental needle assembly 10, each needle part can have a sheath provided for it, each having one said longitudinal entry. A closure for the entry on one sheath can be attached to the other sheath and vice versa.

The invention will be described further, by way of 15. example, with reference to the accompanying drawings , wherein:-

Fig. 1 is an elevation, partly in section, of a conventional dental needle assembly;

Fig. 2 is a similar view of a medical needle assembly; 20. Fig. 3 shows a needle being re-sheathed in conventional manner;

Fig. 4 is an elevation of a dental needle assembly conforming to the invention;

Fig. 5 is an elevation of a major sheath of the 25. assembly of Fig. 4;

Fig. 6 is an elevation of a minor sheath of the ass.emb.ly- of Fig . 4 ;

Fig-.. 7 is a cross section on line 7-7 of Fig. 5. Fig. 8 is an elevation showing a sheath of a first medical needle assembly of the invention; 5« Fig. 9 is an elevation of a sheath of a second medical needle assembly of the invention;

Fig. 10 is an elevation of the assembly of Fig. 9, unused;

Fig. 11 is a cross-section on line II-II of Fig. 8; 10. Fig. 12 is a cross-section on line XII-XII of Fig. 9; Fig. 13 is an enlarged cross-section on line XIII-XIII of Fig. 10;

Fig. 14 is a cross-section comparable to that of Fig. 13, but illustrating an additional variation; 15. Figs. 15a to 15d_ are successive views showing a needle being re-sheathed using a sheath of the present invention;

Figs. 16a and 16b are views comparable with those of 15a to 15d but showing re-sheathing of a shorter needle into 20. a minor sheath of a dental assembly of the invention; Fig. 17 is a vertical cross-section showing the assembly after completion of the process shown in Figs. 16a and 16b_;

Fig. 18a and 18b are cross-sectional views, not to 25. scale, illustrating further possible sheath constructions; Fig. 19 is a perspective view of a development of the sheath shown in Figs. 8 to 12 and 15; Fig. 20 is a similar view of a further development of the sheath shown in Fig. 19;

Fig. 21 is a cross section through the sheath of Fig. 19 or 20 in a closed condition thereof; 5. Fig. 22 is a perspective view of a second still further possible development of the sheath of Figs. 8 to 12 and 15; Fig. 23 shows the sheath of Fig. 22 in use. Fig. 24 is a perspective view of a further possible embodiment of sheath of the invention; 10. Figs. 25 and 26 are cross-sectional views, comparable to those of Figs. 18a and 18b, showing additional possible variations in the cross-sectional shape of a sheath of the invention.

Fig. 27 shows a yet further embodiment; and 15. Fig. 28 shows the embodiment of Fig. 27 in use.

Figs. 1, 2 and 3 illustrate known needle assemblies. The dental needle assembly 10 has its hub 11 push-fitted within a spigot 14 of a major sheath 15, and a minor sheath 16 has its open end 17 push-fitted over spigot 14. This 20. ensures that when the assembly 10 is opened shorter needle 13 is exposed first for connection to a syringe (not shown) by means of thread 18. After such connection the sheath 15 is pulled off and the syringe assembly is ready for use. After use, the longer needle (now very likely contaminated with a 25. patient's blood and/or saliva and/or pus) is re-sheathed into sheath 15 to protect further handlers against injury and/or contamination. Fig. 3 illustrates how an axial mutual approach between sheath 15 (held in the user's fingers 19) and longer needle 12 projecting from the syringe (indicated in outline at 20) is likely to result in injury to the user. When performing tens of such movements per week, the user 5. must eventually miss and when the needle 12 does miss the mouth of sheath 15 (as indicated in dotted lines at 12a) the likelihood of pricking the user's own finger is very great indeed. The possibly catastrophic consequences of a user being injected with contaminated material from a patients

10. body do not need to be stressed.

The dangers of self-injection (so called "finger" or "needle" "stick" or "prick" injuries) are now felt to be so great that some administrators recommend that used needles be not re-sheathed by the user. Adoption of such a practice

15. means that subsequent disposal of used needles becomes a greater hazard for other staff, and that contaminated needles lie exposed for longer periods. Any specific portable means of safe disposal such as a "sharps drum" or bin is often very inconvenient and might encourage non-use by careless staff,

20. leading to other persons being exposed to needle injury and/or contamination. Additionally, during some surgical or medical procedures a practitioner may need to keep a partly-used syringe handy on a trolley during a procedure in case additional drug, eg anaesthetic needs to be

25. administered. In such a situation loss of a "temporary re-sheath" facility would hamper staff and lead to more accidental contact with a syringe left un-sheathed. Fig. 2 illustrates a conventional medical needle assembly 21 which comprises a hub 22 providing a tapered socket 23 to receive a syringe spigot (not shown) and mounting a needle 24 which is enclosed within a sheath 25 5. which is a push-fit on hub 22. The problems involved in re-sheathing a contaminated needle 24 after use are exactly comparable to those involved in re-sheathing a longer needle 12 in Fig. 3.

A first preferred needle assembly 26 of the invention 10. is shown in Fig. 4 to 7 and is a dental needle assembly having a hub 11, shorter needle 13 and longer needle 12. A major sheath 27 thereof is distinguished in that it has therein a longitudinal needle entry in the form of a slot 28 ^•which extends from the open end 29 of sheath 27 to a position 15. nearer to but spaced from the closed end 30. Minor sheath 31 has a similar needle entry in the form of a slot 32. It also has extending therefrom a protrusion 33 which can fill and close slot 28 after a needle 12 has been re-sheathed. Slot 32 serves the same purpose as slot 28 as will be later 20. described. Sheaths 31 and 27 can be moulded from plastics material. Protrusion 33 could be integral with sheath 31. After use, protrusion 33 could be pushed back to enter and wedge within slot 28 as a closure.

Slot 32 could have a similar closure attached to sheath 25.27, but could also remain un-closed, as sheath 27 has a spigot 34 which, in the closed condition enters within the open end of sheath 31 and forms an effective closure for slot 32. A tab 35 on part 33 can facilitate opening.

Fig. 8 shows a needle sheath 35 only of a second needle assembly conforming to the invention. Sheath 35 forms an assembly with a needle/hub combination as shown in Fig. 2. 5.Sheath 35 is distinguished in that it has an entry in the form of a slot 36 extending from open end 37 of sheath 35 to a position nearer to but spaced from the closed end 38. The length of slot 36 is approximately equal to the length of the needle 24 which protrudes from hub 22. Slot 36 is open before

10.and after use. Accordingly, before use needle sterility must be maintained by an additional wrapper or otherwise and after use air-borne contamination must be restricted by other means if it is thought desirable.

Figs. 9 and 10 are comparable views showing a sheath 39

15.of a third preferred assembly of the invention, which assembly is completed by use of a needle/hub combination as shown in Fig.2. This sheath 39 is similar to that of Fig. 8 except that an entry in the form of a slot 40 is closed by a pull-out strip 41. Strip 41 is integral with the sheath 39,

20.is attached at the closed end of the slot 40 and has a tag 42 at its end adjacent the open end 43 of the sheath 39. Fig. 9 shows the sheath 39 opened ready to receive a needle and Fig. 10 shows the sheath 39 before strip 41 has been pulled out of slot 40. Fig. 13 illustrates how in this condition strip 41

25.may be united to the body of sheath 39 by thin tear lines 44 formed by moulding channels 45 in the material of the sheath 39. Fig. 14 is a view comparable to that of Fig. 13 but illustrating a further inventive sheath in which an entry to a sheath 46 is defined by a pair of lips 47 moulded to be separate but urged resiliently towards each other to allow a 5.used needle to be passed into the interior in a movement which forces the lips apart. Such a construction sealingly encloses the needle after introduction, although outer lip praxts may be contaminated.

Fig. 15a to 15d illustrate, sequentially, a preferred 10.method of the invention for sheathing a used needle with minimised danger of injury to the user.

A needle 24, attached to a hub 22 has previously been part of a preferred needle assembly of the invention including a sheath 39. (The method is also applicable to use 15.of separate sheath 35 or a sheath 27) . The user, before use of the syringe, has opened strip 41 and removed sheath 39. After the injection, the user holds the used syringe 95 between the thumb 53 and forefinger 52 of his less dextrous hand (shown as his left hand) with the needle pointing 20. pwards and with the needle and syringe stationary) . He holds sheath 39 in the thumb 62 and forefinger 63 of his other hand. The sheath 39 may be held vertically or nearly vertically. The open end of the sheath 39 is downwards and the slot 40 faces needle 24. 25. Fig. 15a. shows how initial movement from this condition is in the direction of arrow 54 upwardly towards the needle. As the sheath approaches needle 24 (Fig. 15b) the user can angle the sheath 39 slightly to the right in Fig. 16b so that the wider lower edges 40a, 40b of slot 40 pass on opposite sides of the needle before the bulk of the needle enters slot 40. Once the position shown in Fig. 15c is reached the sheath 5. can be moved downwardly and to the left in Fig. 15c: in the direction of arrows 54a_ to shroud the needle tip 2 a_ with the enclosing end portion 39a of sheath 39.

Once the position of 15d is reached the needle tip 24a. is safely enclosed and the user can release the sheath 39 and 10. then slide a finger, such as forefinger 63, down the outside of sheath 39 to direct strip 41 back into slot 40 to form a safe enclosure for the needle 24.

It will be appreciated that the used needle can be held to any desired position other than vertically upwardly 15. extending but, (assuming that the tip of the needle is held to point in a "forward" direction) the user, holding the syringe 95 in one hand and the sheath 39 in digits of the other hand, cannot impale himself. Self-impalement can only occur if the digits (such as 62, 63) of the other hand become 20. disposed forwardly of the tip 24a of needle 24. In the described method, the digits 62, 63 are always rearwardly of the tip 24a of needle 24 and so self impalement is extremely unlikely.

Figs. 16a., 16b and 17 are comparable in many ways to 25. Figs. 15a to 15d in that they described how the sheath 31 of Fig. 6 can be replaced to cover a needle 13 of a dental assembly which includes integral needle 12 and 13. After use of a dental assembly the longer, injecting, needle 12 is sheathed in a manner comparable with the method of Figs. 15a to 15d. Its hub 11 is then unscrewed from a container to expose smaller needle 13. Again the assembly held with needle 5.13 upwardly directed, stationary and away from the user and his second (right) hand. Minor sheath 31 is then picked up by the thumb 60 and forefinger 61 of the users right hand and moved upwards and towards needle 13 in a manner exactly comparable to the method of Figs. 15a to 15d. After union, th 10.needle 13 is protected within the closed end portion 31a of sheath 31. An upper portion of slot 32 remains open in this case, but the risk associated with such opening is small. As mentioned later, however, a tongue on sheath 27 or sheath 31 could be provided to close slot 32 after use. Alternatively, 15. the length of slot 32 could be reduced to ensure that in the Fig. 4 condition it is completely closed by underlying spigot 34.

The invention is not limited to the precise details of the foregoing and variations can be made thereto. For 20.example, a protective sheath such as sheath 27 or 39 can be provided as a separate item for receiving and protecting a used needle. An open-entry sheath can be provided in addition to a supply sheath and be used solely to receive, store and shroud a used needle. An openable entry can be provided by a 25.moulded plastics sheath having a line of weakness and/or a tear-string or wire, operation of which, initially, opens the sheath and entry to allow re-sheathing of a needle after use. A sheath 57 of the sort shown in Figs. 18a could have a teax⁵-strip 58 separated from the body of the sheath by weakened portions, parts of the body adjacent the so-formed entry could be formed as complementary sealing formations 59 5. to allow re-closing of the sheath after re-sheathing of a needle. A similar, if simpler construction is shown in Fig. 18b, wherein a single weak line could be broken by a pull—string or simply by pressure in that direction of arrows AA, a re-sealing after use could be achieved by pressure in

10. the direction of arrows B,B.

The sheath 65 shown in Fig. 19 illustrates a variation to the sheath 39 of Figs. 9 and 10. With the sheath 39 it is possible (if re-sheathing is carried out improperly) for the needle to remain projecting from the entry when the hub has

15. entered into the open end of the sheath 39. This requires the user to apply excessive force and even deform the needle and/or sheath. It is likely to be a rare occurrence but might happen in the case of use in haste or by clumsy personnel. To obviate this danger, the sheath 65 has a body

²⁰- 66 with slot 67 and a complementary closure strip 68 comparable with strip 41.

Strip 68 has outwardly extending wings 69, thinner than strip 68, which, when the sheath 65 is closed (Fig. 21) embraces substantial part of the cross-sectional periphery

25. ₀f the body 66. Wings 69 serve two purposes. Firstly, if a needle is protruding from slot 67 a user who pushes strip 68 to close slot 67 is much less likely to contact the needle. Also, the presence of the needle will hinder movement of strip 68 giving a signal to the user that all is not well. Secondly in normal or abnormal use the needle will often contact the edges of slot 67 leaving possibly contaminated 5. body material thereon. With the sheath 39, a user closing strip 41 can contact such material (albeit usually with a gloved finger) and become contaminated. With a winged strip 68, any such contaminated edge areas are covered and enclosed by the wings 69. 10. Fig. 20 discloses a variation of sheath 65a in which the body 66 has around it on the side of the hinge of strip 68 immediately adjacent nearer closed end and encircling the body 66 an outstanding rim 70 which sheath reinforces the protection of the wings 69, in the (admittedly unlikely) 15. event that a user directs a needle 79 (shown in dot dash lines in Fig. 20. In this event the needle 79 could pass between the hinge end of a wing 69 and stick a user's finger holding sheath 65. Rim 70 forms a barrier to a needle 79 passing significantly beyond the hinge end of wing 69. 20. Naturally, the improvements described in Figs. 19 to 21 are equally applicable to sheaths of cross-sectional shapes other than hexagonal, for example the circular-sectioned sheaths of Figs. 9 and 10. Also, a pair of wings comparable to wings 69 can be added to strip 33 (Figs. 6 and 16) for the 25. same purpose.

Figs. 22 and 23 illustrate an additional variation wherein a sheath 71 has a body 72, a slot 73 and a closure strxp 74. Strip 74 has a laterally extending projection 75 at its free end to facilitate opening of the sheath with a gloved finger. Projections comparable to projection 75 can be provided on strips 33 and 41. At the open end of sheath 71 is 5. a projection 76 which serves as a handle in the manner of strip 33 (Fig. 16) and helps place the user's fingers further away from the point of a needle. This modification is particularly desirable in relation to short needles. To accommodate the bulk of a syringe 78, the axial-parallel

10. projection 76 is spaced outwardly from the sheath axis 77. As a further possible variation sheath 27 of Fig. 5 could have an extension to fit in and/or overlie slot 32.

Fig. 24 shows a sheath 80 which has a moulded body 81 with an entry in the form of a longitudinal slit 82 defined

15. between opposed edge faces 83 on body 81. The sheath 80 can be moulded to have the edge faces 83 resiliently urged together or they can be separable and closeable. A hinge line 84 directly opposite slit 82 facilitates opening and closing of the entry. Figs. 25 and 26 show possible cross-sectional

20. shapes for sheaths conforming to Fig. 24. In Fig. 25 a longitudinal hinge 85 is provided opposite plug and socket sealing formations 86. In Fig. 26, an inwardly disposed tongue 87 is provided on one edge 90 of an entry slot 88 in sheath 89. Tongue 87 engages beneath an opposite edge 91

25. (possibly being a snap fit therewith) . The tongue 87 can be resilient to be displaced by an entering needle and form, with lip 91 a "no-exit" closure to the sheath. When the sheath 39 of Figs. 9 and 10, of any sheath having a closure fitting an entry slot, it will be appreciated, see for example Figs. 15d, that the open end of sheath 39 is splayed due to engagement with a frusto-conical 5. surface on a hub 22. To prevent such splaying widening the entry so much as to make a closure loose fit therein, a hub 2.2 can be supplied to limit its penetration into a sheath 39.

Figs. 27 and 28 illustrate an additional possible embodiment of sheath 93 illustrated in closed and open 10. positions respectively. Sheath 93 has a body 94 with a slot 95 initially closed by a strip 96 which is integral with a cap 97 for the open end of body 94.

A joint or a line of weakness can separate the rim 98 of cap 97 from body 94 and the flanks of strip 90 from the 15. body 94. The line of weakness at the rim 98 is shown in dotted lines in Fig. 27.

Sheath 93 is supplied closed and enclosing a hub/needle combination 99. After use the combination 99 can be replaced in a manner comparable to those disclosed previously. Closing 20. of the slot 95 simultaneously closes the open end of body 94 by cap 97. There can be a snap fit between cap 97 and body 94 or friction between strip 96 and slot 95 can be relied upon to keep the used sheath closed. A tag or lip on cap 97 can be provided to facilitate opening.

Claims

1. A needle assembly including a hub, a needle and a sheath, the sheath having a longitudinal entry whereby a needle can be introduced into the sheath by a movement

5. having at least a substantial component transverse to the length of the needle.

2. An assembly as claimed in claim 1 wherein in a pre-use condition the sheath surrounds the needle and the two can be separated for use of the needle before the needle is

10. re-introduced into said sheath with said movement.

3. An assembly as claimed in claim 1 or 2, wherein said sheath is initially releasably connected to said hub and the needle and sheath can be separated by relative axial movement.

15.

4. An assembly as claimed in claim 1, 2 or 3 and formed from plastics material.

5. An assembly as claimed in any preceding claim, wherein the longitudinal entry extends over less than the full length of the sheath from an open end thereof 0- to near to but spaced from a closed end thereof.

6. An assembly as claimed in claim 5 wherein the length of the entry is between 50% and 90% of the full length of the sheath.

7. An assembly as claimed in claim 5 or 6 wherein said 5. sheath and said hub are such as to allow relative movement between the sheath and needle after entry of said needle laterally into the sheath to dispose a tip of the needle within a closed end portion of the sheath.

8. An assembly as claimed in any preceding claim wherein 10. said entry is an open slot wider than the needle.

9. An assembly as claimed in any of claims 1 to 7 wherein said entry has lips which are normally engaged but can be separated by a needle in such entry movement.

10. An assembly as claimed in any preceding claim wherein 15.^'. in an initial supply condition of the assembly said entry is closed, but can be opened in use to allow entry of said needle.

11. An assembly as claimed in claim 10, wherein said entry is openable by an action, as tearing or pressing, which

20. causes rupture of a line or lines of weakness at least partially defining said entry.

12. An assembly as claimed in claim 10 wherein said entry is openable by removal of a part from said sheath.

13. -An assembly as claimed in claim 12, wherein said part is permanently attached to the sheath and can be replaced in

5. the slot left by it when removed (said slot constituting the entry) to enclose a used needle.

14. An assembly as claimed in claim 13 wherein the part is a strip extending longitudinally of the sheath and hinged to the sheath at an end of the strip nearer the closed end of

10. the sheath.

15. An assembly as claimed in claim 14 wherein said strip has laterally extending wings which in a closed condition of the strip .cover edges of the entry slot.

16. An assembly as claimed in claim 15, wherein the wings 15. are inwardly directed to conform to the shape of a body of the sheath and closely overlie the body in a closed condition thereof.

17. An assembly as claimed in any of claims 12 to 16 wherein the said part has an outwardly extending protrusion

20. which enables said part to be lifted easily by a gloved finger of a user for opening the entry.

18. A sheath, for reception of a needle, including a longitudinal entry via which a needle can be introduced into the sheath in a movement having at least a major component in a direction transverse to the major axis of the needle.

5.

19. A sheath as claimed in claim 13, wherein the entry is a slot which extends from an open end of the sheath.

20. A sheath as claimed in claim 14 wherein the length of the entry is less than the full length of the sheath.

21. A sheath as claimed in claim 15, wherein the length of 10. the entry is from 90% to 50% of the length of the sheath.

22. A sheath as claimed in any of claims 13 to 16 and in the form of a cavity formed in a body, the body having said entry communicating with said cavity.

23. A sheath as claimed in any of claims 18 to 22 wherein !5. the entry is formed by removing a part from the sheath.

24. A sheath as claimed in claim 23 wherein said part is permanently attached to the sheath and can be replaced in the slot left by it when removed (said slot constituting the entry) to enclose a used needle.

20.

25. A sheath as claimed in claim 24 wherein the part is a strip extending longitudinally of the sheath and hinged to the sheath at an end of the strip nearer the closed end of the sheath.

26. A sheath as claimed in claim 25 wherein said strip has 5.laterally extending wings which in a closed condition ^"of the strip cover edges of the entry slot.

27. A sheath as claimed in claim 26, wherein the wings are inwardly directed to conform to the shape of a body of the sheath and closely overlie the body in a closed condition

10.thereof.

28. A sheath as claimed in any of claims 23 to 27 wherein the said part has an outwardly extending protrusion which enables said part to be lifted easily by a gloved finger of a user for opening the entry.

15.

29. A needle assembly as claimed in any of claims 1 to 17 or a sheath as claimed in any of claims 18 to 28, wherein the sheath has a projection extending outwardly and rearwardly from its open end to constitute a handle to dispose a user's fingers further from a needle point during sheathing thereof.

20.

30. A needle assembly as claimed in any of claims 1 to 17, wherein the hub has a second needle extending from it in a direction opposite to that of the one needle and there is a second sheath for the second needle, said entry for the needle in the one sheath being initially closed by a tear-out strip connected at one end to the other sheath and projecting therefrom to form a handle for the other sheath when said 5. second needle is introduced into an entry in the second sheath.

31. An assembly as claimed in claim 30, wherein the second needle is shorter than said first needle.

32. A needle assembly as claimed in any of claims 1 to 17, 10. or in claim 30 or 31 and being a hypodermic needle assembly.

33. A method of forming a protective covering for a needle after use, comprising providing a sheath having a longitudinally extending entry, supporting said needle by means of a hub, and causing relative movement between said

15. needle and said entry such that said needle enters said entry in a movement of which at least a major component is transverse to a longitudinal axis of the needle.

34. A method as claimed in claim 33 wherein said needle is supported by a user's one hand and the sheath is supported

20. by the user's other hand, the sheath being supported by a pair of digits on the users other hand with its open end at or near said digits and with its other end spaced away from said digits positioned with its point laterally spaced from said other hand, considering a point of said needle to be directed in a forward direction, the sheath is moved, from a position rearwards of the needle, forwardly towards the needle and the entry progressed to enclose the needle in a 5. motion which has at least a major component in a direction transverse to the needle axis.

35\. A method as claimed in claim 34, wherein during said movement the separation between the needle point and said digits is never less than half the length of the needle.

10.

36. A method as claimed in claim 34 or 35, wherein during said movement the separation of the end of the needle from said digits, measured lengthwise of the needle, never decreases during a final part of said movement while the needle is being enveloped within the sheath.

15.

37. A method of forming a protective covering for a needle substantially as hereinbefore described.

38. An assembly as claimed in claim 1 or a sheath as claimed in claim 18, wherein the longitudinal entry is defined between opposing edges on a body of the sheath, a tongue 20. being provided internally of one of the edges and extending internally of the other edge to bridge the entry inside the sheath.

39. An assembly or sheath as claimed in claim 38 wherein the tongue forms a snap fit with the interior of the second edge.

40. An assembly as claimed in claim 14 or a sheath as

5. claimed in claim 24, wherein the strip is connected to a cap which can close an end of the body.

41. A needle assembly substantially as described with reference to Figs. 4 to 7, 19 and 20 or Figs. 22 and 23.

42. A sheath, for a needle, substantially as herein

10. described with reference to Figs. 8, 9, 10, 15, 19 or 20.