Systems and methods for a safety syringe

Abstract

To provide safe injection systems and devices having retractable needles.SOLUTION: A syringe assembly includes a syringe body, a needle assembly, a retaining clip, a gasket, a needle latch, and a needle hub. The syringe body has a syringe interior, a longitudinal axis, proximal and distal ends, and a needle attachment interface disposed at the distal end thereof. The gasket is configured to be compressed to provide a liquid-tight seal around an outer diameter of the needle assembly and the distal end of the syringe body. A needle latch assembly includes latching tabs configured to retain the needle assembly in a close state and to be plastically deformed to an open state to release the needle assembly, and a gasket backstop configured to provide a flat surface for compression of the gasket, where the latching tabs are disposed at a distance from the gasket such that none of the latching tabs contacts the gasket during compression of the gasket.SELECTED DRAWING: Figure 26

Description

Technical Field

[0001] The present invention generally relates to infusion systems and devices, and more particularly to infusion systems and devices related to infusion in a medical environment. Even more particularly, the present invention relates to safety infusion systems and devices having retractable needles, and methods for manufacturing, assembling and using them.

Background Art

[0002] Millions of syringes, such as those shown in FIG. 1A(2), are consumed daily in a medical environment. A typical syringe (2) includes a tubular body (4), a plunger (6) and a hypodermic needle (8). As shown in FIG. 1B, such a syringe (2) can be used not only to inject fluid into a patient, but also to draw fluid from a container such as a vial, ampoule, bag or other drug encapsulation system (10), or to discharge fluid into those containers. In fact, in some countries such as the United States, due to concerns about maintaining sterility and regulatory constraints, when a vial (10) is used with a syringe (2) as shown in a particular patient's environment, such a vial can only be used for a single patient and then must be disposed of, thereby resulting in a large amount of medical waste from the vial and the remaining drug waste, and also causing periodic shortages of certain important drugs.

[0003] Referring to FIG. 2A, three luer-type syringes (12) are shown, each having a luer fitting shape (14) disposed distally, and they are adapted to be coupled with other devices having a similar fitting shape, such as the luer manifold assembly (16) shown in FIG. 2B. The luer manifold assembly of FIG. 2B can be used to administer a liquid drug intravenously to a patient, with or without the use of an intravenous infusion bag. The luer fitting (14) of the syringe in FIG. 2A is sometimes referred to as a "male" luer fitting, and the luer fitting (18) in FIG. 2B is sometimes referred to as a "female" luer fitting. One of the luer interfaces has threads formed thereon (in this case, the configuration may also be referred to as a "luer lock" configuration), and the two are coupled by relative rotation, which may be combined with a compressive load in some cases. In other words, in one embodiment of the luer lock, rotation is utilized, optionally together with compression, to engage the threads of the male fitting (14), which are configured to engage a flange on the female fitting (18) to place the device in a fluid-tight coupled state. In another embodiment, a tapered interface shape may be utilized to provide luer engagement using compression without the use of threads or rotation (such a configuration may also be referred to as a "slip-on" or "cone" luer configuration). Such luer connections are recognized as being relatively safe for an operator, but there is a risk that the drug may spill, leak, or the components may be damaged during the assembly of the luer connection.

[0004] On the one hand, when using a needle injection configuration, there is a risk that the sharp needle may come into contact with or pierce a person or an undesirable structure. For this reason, so-called "safety syringes" have been developed. One embodiment of a safety syringe (20) is shown in FIG. 3, in which a tubular shield member (22) is spring-biased to cover the needle (8) when released from the locked position relative to the syringe body (4). Another embodiment of a safety syringe (24) is shown in FIGS. 4A and 4B. In this configuration, after the plunger (6) is fully inserted into the syringe body (4), as shown in FIG. 4B, a retractable needle (26) is configured to be retracted (28, 26) to a safe position within the tubular body (4). Such forms configured to retract themselves may be associated with problems of blood splashing / aerosolization, safe storage of pre-loaded energy that may malfunction and act too quickly, loss of accuracy in delivering a full dose injection due to residual dead space within the spring compression volume, and / or loss of retraction speed control that may be associated with pain or patient discomfort.

[0005] The syringe market has become further complicated by the increasing demand for prefilled syringe assemblies as shown in FIGS. 5A and 5B, which generally include a syringe body or "drug containment delivery system" (34), a plunger tip, plug or stopper (36), and a distal seal or cap (35) attached to a luer-type interface (FIG. 5A shows the cap 35 in a fixed position, while FIG. 5B shows the cap removed to illustrate the luer-type interface 14). The liquid drug is in a volume or drug reservoir (40) between the distal seal and the distal end (37) of the plunger tip (36). The plunger tip (36) can include a standard butyl rubber material and is coated with a biocompatible lubricious coating (such as polytetrafluoroethylene ("PTFE")) to facilitate favorable sealing and relative movement characteristics with respect to the associated syringe body structure and materials. The proximal end of the syringe body (34) in FIG. 5B includes a conventional integral syringe flange (38) formed integrally with the material of the syringe body (34). The flange (38) is configured to extend radially from the syringe body (34) and to be a full circumference or a partial circumference around the syringe body (34). A partial flange is known as a "clipped flange", while the other flange is known as a "full flange". The flange is used for gripping the syringe with the fingers and provides support for pushing the plunger to effect an injection. The syringe body (34) preferably includes a translucent material such as glass or polymer. The plunger tip (36) can be disposed within the syringe body (34) to form a volume contained within the chamber or reservoir (40) and to assist in the discharge of the associated fluid through the needle. The syringe body (34) can be defined as generally cylindrical (i.e., such that a plunger tip 36 having a circular cross-sectional shape establishes a seal with respect to the syringe body (34)), or can be configured to have other cross-sectional shapes such as elliptical.

[0006] Such assemblies are desirable because they can be standardized and accurately mass-produced by a few manufacturers in the world who have the capacity to meet all of the constantly changing regulations regarding filling, packaging, and the selection of pharmaceutical / drug interfacing materials and the use of components. However, with such a simple configuration, generally, they cannot meet the new world standards regarding single-use, safety, automatic deactivation, and needle-stick prevention. For this reason, certain suppliers have moved towards more "vertical" solutions, such as the one shown in Figure 5C (41), that attempt to meet all or at least some of the standards in one solution. As a result of attempting to meet those standards in many different scenarios, such products have significant limitations (including the limitations described above with reference to Figures 3 to 4B), and the inventory and usage costs can be relatively high.

[0007] Some injection system bodies are formed by molding a polymer such as cyclic olefin copolymer ("COC") or cyclic olefin polymer ("COP"). Molding the injection system body is a cost-effective and high-throughput method for manufacturing injection system components with an acceptable error rate. For example, Figure 6 shows a molded polymer syringe body 600 that includes an integral luer connector 610 and internal threads 612 to facilitate the attachment of a needle hub assembly (not shown) to the molded polymer syringe body 600. The luer connector 610, the internal threads 612, and the distal end of the syringe body 600 having the internal threads 612 together form a luer nut 614. The integrated luer nut 614 eliminates the step of attaching the luer nut to the distal end of the syringe body.

[0008] Some needle retraction systems include a needle latch assembly that releasably / temporarily couples a needle assembly to a needle hub (and the injection system body / syringe body coupled thereto) until the needle latch assembly is released such that the needle assembly is at least partially retracted into the injection system body / syringe body. The needle latch assembly typically remains latched and stationary throughout the injection process with a proximal-directed force of 0.25 pounds to 0.5 pounds applied to the needle assembly as it penetrates the patient's skin. Retracting the needle assembly moves the sharp distal end of the needle into the interior of the needle hub or injection system body / syringe body, preventing accidental needle sticks. Some existing needle retraction systems include a number of components that increase system cost and manufacturing / assembly complexity.

[0009] There is a need for needle retraction systems and components thereof that address the drawbacks of currently available configurations. In particular, there is a need for a needle latch assembly with a reduced number of parts while retaining the functionality of releasably / temporarily coupling a needle assembly to a needle hub. By addressing these and other limitations of needle retraction systems, it becomes possible to incorporate a cost-effective and easily manufacturable data retraction system into a safer injection system. SUMMARY OF THE INVENTION

[0010] Embodiments relate to an injection system. In particular, embodiments are directed to a safe injection system having a needle latch assembly with a small number (e.g., one or two) of parts to reduce cost and simplify manufacturing / assembly.

[0011] In one embodiment, the syringe assembly includes a syringe body, a needle assembly, a retaining clip, a gasket, a needle latch, and a needle hub. The syringe body has an interior of the syringe, a longitudinal axis, a proximal end and a distal end, and a needle attachment interface disposed at its distal end. The needle assembly has a proximal end and a distal end. The retaining clip has retaining barbs. The gasket is configured to be compressed to provide a liquid-tight seal around the outer diameter of the needle assembly and at the distal end of the syringe body. The needle latch assembly includes first and second latch tabs configured to hold the needle assembly in a closed state and plastically deform to an open state to release the needle assembly, and a gasket backstop configured to provide a flat surface for compression of the gasket, wherein the first and second latch tabs are spaced apart from the gasket such that neither the first nor the second latch tab contacts the gasket during compression of the gasket. The needle hub has a plurality of inner surfaces configured to hold the needle latch assembly, the gasket, the retaining clip, and the distal end of the syringe body in a sealed configuration to prevent leakage of liquid outside the needle hub during injection using the syringe assembly. The needle assembly is configured to be retracted into the syringe body after injection using the syringe assembly.

[0012] In one or more embodiments, the needle latch assembly further includes a cage, the cage including a flat body defining a larger opening and first and second arms extending orthogonally from the flat body. The first and second latch tabs extend orthogonally from the first and second arms, respectively, to define a smaller opening. The larger opening is sized and shaped such that the needle assembly can pass through. The smaller opening is sized and shaped to prevent passage of the needle assembly until the first and second latch tabs are deformed.

[0013] In one or more embodiments, the first and second latch tabs are plastically deformable. The first and second latch tabs can be configured to plastically deform when a proximally directed force of 2 to 3 pounds is applied. The first and second latch tabs may be symmetric. The larger opening can be disposed at the center of the flat body. The smaller opening can be coaxially disposed with the larger opening. The first and second latch tabs can be configured to engage with and disengage from the needle while remaining inside the cage.

[0014] In one or more embodiments, the first and second arms are elastically deformable. Each of the first and second arms can include first and second pairs of standoffs at an end opposite the flat body of the cage. The first and second pairs of standoffs may be bent relative to each other. The first and second arms may each be arcuate when viewed axially. The flat body, the first and second arms, and the first and second latch tabs may be punched or cut out as a single piece from a metal sheet.

[0015] In one or more embodiments, the needle latch assembly includes an upper flat disk-shaped body having first and second latch tabs that define the smaller opening, and a larger opening is defined in the upper flat disk-shaped body. The assembly includes a lower flat disk-shaped body having an oval opening defined therein. The assembly further includes a plurality of coupling members coupled to the upper and lower flat disk-shaped bodies such that the oval opening defined in the lower flat disk-shaped body is aligned with the smaller and larger openings defined in the upper flat disk-shaped body. The larger opening is sized and shaped to allow the needle assembly to pass through. The smaller opening is sized and shaped to prevent the passage of the needle assembly until the latch tabs are deformed.

[0016] In another embodiment, the syringe assembly includes a syringe body, a needle assembly, a retaining clip, a gasket, a needle latch assembly, and a needle hub. The syringe body has an interior of the syringe, a longitudinal axis, a proximal end and a distal end, and a needle attachment interface disposed at its distal end. The needle assembly has a proximal end and a distal end. The retaining clip has retaining barbs. The gasket is configured to be compressed to provide a liquid-tight seal around the outer diameter of the needle assembly and at the distal end of the syringe body. The needle latch assembly includes a flat disk-shaped body having first and second opposing deformable latch tabs that define a smaller opening, and a larger opening is defined in the flat disk-shaped body. The needle hub has a plurality of inner surfaces configured to hold the needle latch assembly, the gasket, the retaining clip, and the distal end of the syringe body in a sealed configuration during injection using the syringe assembly to prevent leakage of liquid outside the needle hub. The larger opening is sized and shaped such that the needle assembly can pass through. The smaller opening is sized and shaped to prevent passage of the needle assembly until the latch tabs are deformed. The needle assembly is configured to be retracted into the syringe body after injection using the syringe assembly.

[0017] In one or more embodiments, the first and second latch tabs are plastically deformable. The first and second latch tabs can be configured to plastically deform when a proximally directed force of 2 to 3 pounds is applied. The first and second latch tabs may be asymmetric. The force to plastically deform the latch tabs to release the needle for retraction can be adjusted to match the requirements of the intended needle insertion force. Typically, a force of 0.25 to 0.5 pound is required to pierce the skin and / or insert the needle to the injection depth. The latch tabs are sized to generate a needle holding force of about 2 to 3 pounds, such that the margin of release force / puncture force is 4 to 12 (2 / 0.5 = 4 to 3 / 0.25 = 12). A margin of needle holding force greater than the needle piercing force is desired to ensure retraction of the needle while overcoming friction between the skin and the needle, friction between the stopper and the needle, and / or friction in the retraction mechanism. For example, when the tissue is dense, a high needle release force of 3 to 5 pounds may be desired. On the other hand, when the tissue density is low, a low needle release force of 1.0 to 2.0 may be desired. The retraction spring is sized to provide a needle retraction force greater than the needle holding force to ensure reliable retraction of the needle. A stronger retraction spring typically provides a faster needle retraction, while a weaker retraction spring typically provides a slower retraction. The larger opening may be positioned eccentrically with respect to the center of the flat disk-shaped body. The smaller opening may be positioned at the center of the flat disk-shaped body.

[0018] In one or more embodiments, the flat disk-shaped body is punched or cut from a metal sheet. The upper and lower flat disk-shaped bodies and the plurality of coupling members may be punched or cut as a single piece from the metal sheet. Metal can be easily created by punching and is suitable for the disk because of its creep resistance. Alternatively, the disk can also be formed from a polymer or rubber material.

[0019] In one or more embodiments, a "H"-shaped opening is also defined in the flat disk-shaped body. A side opening is also defined in the flat disk-shaped body on the opposite side of the larger opening, and this side opening is connected to the "H"-shaped opening and the outside of the flat disk-shaped body. The flat disk-shaped body can also have an elastically deformable section adjacent to the larger opening and disposed on the opposite side of the side opening. The flat disk-shaped body may be configured to elastically deform in the plane of the flat disk-shaped body by the elastically deformable section to expand the side opening. The flat disk-shaped body is configured to elastically deform out of the plane of the flat disk-shaped body by the elastically deformable section to expand the side opening.

[0020] In yet another embodiment, the syringe assembly includes a syringe body, a needle assembly, a retaining clip, a gasket, a needle latch assembly, and a needle hub. The syringe body has a syringe interior, a longitudinal axis, a proximal end and a distal end, and a needle attachment interface disposed at its distal end. The needle assembly has a proximal end and a distal end. The retaining clip has retaining barbs. The gasket is configured to be compressed to provide a liquid-tight seal around the outer diameter of the needle assembly and at the distal end of the syringe body. The needle latch assembly includes a rectangular prism retaining portion sized and shaped to be disposed in a space defined within the needle hub. The assembly also includes a cylindrical collar portion sized and shaped to prevent the needle assembly from passing until the cylindrical collar portion deforms. The assembly further includes a coupling portion coupled to the rectangular prism retaining portion and the cylindrical collar portion. The needle hub has a plurality of inner surfaces configured to hold the needle latch assembly, the gasket, the retaining clip, and the distal end of the syringe body in a sealed configuration to prevent liquid from leaking out of the outside of the needle hub during injection using the syringe assembly. The needle assembly is configured to be retracted into the syringe body after injection using the syringe assembly.

[0021] In one or more embodiments, the rectangular prism retaining portion includes a pair of latched tabs biased outwardly in a size and shape to retain the rectangular prism retaining portion within a space defined within the needle hub. The cylindrical collar portion can include a wound sheet having a longitudinal opening to facilitate deformation of the cylindrical collar portion. The cylindrical collar portion may be plastically deformable. The cylindrical collar portion may be configured to plastically deform when a proximally directed force of 2 to 3 pounds is applied. The rectangular prism retaining portion, the cylindrical collar portion, and the coupling portion may be punched or cut from a metal sheet as a single piece.

[0022] The above-described and other embodiments of the present invention are described in the following detailed description.

Brief Description of the Drawings

[0023] The following drawings are for illustrative purposes only. The drawings are not intended to limit the scope of the present disclosure. The above-described and other aspects of the embodiments are described in more detail with reference to the accompanying drawings, in which like elements in the various drawings are denoted by common reference numerals.

[0024]

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[0025] To better understand the above and other advantages and objects of various embodiments, a more detailed description of the embodiments will be provided with reference to the accompanying drawings. Note that the drawings are not drawn to scale, and it should be noted that elements of similar structure or function are denoted by like reference numerals throughout. It should be understood that these drawings show only specific exemplary embodiments and should not be considered as limiting the scope of the embodiments.

Best Mode for Carrying Out the Invention

[0026] Exemplary safety injection system Figures 7A and 7B show a partially assembled safety injection system 700 according to some embodiments. The safety injection system 700 includes a needle hub assembly 710 coupled to a syringe body 720. The syringe body 720 may be a molded polymer syringe body. The needle hub assembly 710 includes a needle assembly 730.

[0027] Although not shown in Figures 7A and 7B, the safety injection system 700 includes a needle retraction system. The needle retraction system (not shown) applies a proximally directed force to the needle assembly 730 after injection is complete to at least partially retract the needle assembly 730 into the needle hub assembly 710 and / or the syringe body 720 in order to prevent accidental needlesticks by disposing the sharp distal tip 736 of the needle assembly 730 within the needle hub assembly 710 and / or the syringe body 720. In some embodiments, the proximally directed force is from about 2 pounds to about 3 pounds.

[0028] The needle hub assembly 710 includes a needle latch assembly (shown in various embodiments and described below) configured to releasably couple a needle assembly 730 to the needle hub assembly 710 in a latched latch configuration. In the latched configuration, the needle latch assembly 710 prevents movement of the needle assembly 730 relative to the needle hub assembly 710 and the syringe body 720 coupled thereto. When the needle latch assembly transitions from the latched configuration to the unlatched configuration, the needle assembly 730 is no longer coupled to the needle hub assembly 710 and can thus move freely relative to the needle hub assembly 710 and the syringe body 720. In other words, in the unlatched, unlatched configuration, the needle latch assembly allows the needle assembly 730 to be at least partially retracted into the needle hub assembly 710 and / or the syringe body 720, as described above.

[0029] Exemplary flat disk-shaped needle latch assembly Figures 8A - 16D show various flat disk-shaped needle latch assemblies according to various embodiments and their incorporation into a needle hub assembly and a safety injection system.

[0030] Figures 8A and 8B show a safety injection system 800 according to some embodiments. Figures 8A and 8B show the safety injection system 800 in an assembled and ready-to-use configuration. The safety injection system 800 includes a needle hub assembly 810 coupled to a syringe body 820 and a needle assembly 830. The syringe body 820 includes a syringe interior, a longitudinal axis, a proximal end and a distal end, and a needle attachment interface disposed at its distal end. The needle hub assembly 810 includes a needle latch assembly 840 configured to releasably interfere with a notch 832 of the needle assembly 830 to releasably couple the needle assembly 830 to the needle hub assembly 810. The needle latch assembly 840 is shown in Figures 12A and 12B and is a flat disk / ring as described below.

[0031] The safety injection system 800 also includes a deformable seal member / gasket 850 disposed between the distal end 822 of the syringe body 820 and the proximal side of the needle latch assembly 840. The deformable seal member 850 can take the form of an elastomeric polymer disk / ring, such that when the safety injection system 800 is assembled, the deformable seal member 850 can fill the space within the needle hub assembly 810 that holds the needle latch assembly 840 to provide a fluid-tight seal.

[0032] Figures 9A and 9B show the safety injection system in two exploded views to more clearly illustrate the components of the safety injection system 800. As shown in Figures 9A and 9B, the needle assembly 830 includes a distal shoulder 834 that interferes with a proximal shoulder 812 formed on the inner surface of the needle hub assembly 810 to limit distal movement of the needle assembly 830 relative to the needle hub assembly 810. Figures 8A and 8B show the distal shoulder 834 of the needle assembly 830 abutting against the proximal shoulder 812 of the needle hub assembly 810 to limit distal movement of the needle assembly 830 relative to the needle hub assembly 810. Also, Figures 9A and 9B show the deformable seal member 850 in a non-compressed / relaxed state. Figures 8A and 8B show the deformable seal member / gasket 2450 in a compressed / biased state.

[0033] Figures 10A and 10B show the safety injection system in two further exploded views to more clearly illustrate the components of the safety injection system 800. The safety injection system 800 also includes a needle hub retaining ring / clip 860 having a retaining barb that is configured to prevent the needle hub assembly 810 from moving distally relative to the syringe body 820 while allowing the needle hub assembly 810 to move proximally relative to the syringe body 820 (e.g., a molded polymer syringe body) after the two components are joined together during assembly.

[0034] During the manufacture / assembly of the safety injection system according to some embodiments, the needle latch assembly 840 and the deformable seal member 850 are passed over the needle assembly 830 until the needle latch assembly 840 is partially disposed within the notch 832 of the needle assembly 830 and held in place by the deformable seal member 850 on its proximal side. Thereafter, the needle hub retaining ring 860 is inserted and the needle hub assembly 810 is passed over the distal end 836 of the needle assembly until the distal shoulder 834 of the needle assembly 830 abuts the proximal shoulder 812 of the needle hub assembly 810. The needle assembly 830 is configured such that when its distal shoulder 834 abuts the proximal shoulder 812 of the needle hub assembly 810, the needle latch assembly 840 abuts the proximal inner wall 814 of the needle hub assembly 810. Next, the syringe body 820 is passed over the proximal end of the needle assembly 830 and advanced distally until the distal end 822 of the syringe body 820 abuts the proximal side of the deformable seal member 850. The distal end 822 of the syringe body 820 compresses the deformable seal member 850 until it fills the space of the needle hub assembly 810 that holds the needle latch assembly 840 and provides a fluid-tight seal. Thereafter, other parts of the safety injection system (e.g., stopper member, plunger member, etc.) are added to the syringe body 822 and the manufacture / assembly of the safety injection system is completed.

[0035] The method of manufacturing / assembling the safety injection system described above includes various operations in a specific order, although methods according to some other embodiments can include operations in a different order.

[0036] Figures 11A and 11B show a needle assembly 830 according to some embodiments. The needle assembly 830 includes a notch 832 for interacting with a needle latch assembly (not shown; see FIG. 8A), a distal shoulder 834 for interacting with a proximal shoulder inside the needle hub assembly 810 (not shown; see FIG. 8A), and a sharp distal end 836.

[0037] Figures 12A and 12B illustrate a needle latch assembly 840 according to some embodiments. The needle latch assembly 840 is a flat disk-shaped body. The needle latch assembly 840 includes first and second opposing deformable tabs 841, 842. The first and second opposing deformable tabs 841, 842 are asymmetric, and their opposing edges partially define a smaller opening 843 located substantially at the center of the flat disk-shaped body. The needle latch assembly 840 also includes an "H"-shaped opening 844 partially defined by the first and second opposing deformable tabs 841, 842.

[0038] Near the center of one of the long legs of the "H"-shaped opening 844, a larger opening 845 is formed. This larger opening 845 is disposed eccentrically with respect to the center of the flat disk-shaped body. The larger opening 845 is sized and shaped such that the needle assembly 830 can pass through it (see Figure 13A). On the other hand, the smaller opening 843 is sized and shaped to prevent the needle assembly 830 from passing longitudinally through it (see Figure 14A). Thus, during manufacturing / assembly as shown from Figure 13A to Figure 14B, the needle assembly 830 can be inserted through the larger opening 845 (Figure 13A) and slid into the smaller opening 843, and the smaller opening is sized and shaped to allow the notch 832 of the needle assembly 830 to face in a direction orthogonal to the longitudinal axis of the needle assembly 830. After the needle assembly 830 is slid from the larger opening 845 to the smaller opening 843, the needle assembly 830 is prevented from moving longitudinally until the first and second opposing deformable tabs 841, 842 are deformed.

[0039] The first and second opposing deformable tabs 841, 842 are configured to plastically deform when a force of a preset magnitude is applied to the tabs 841, 842 in the proximal direction. In some embodiments, the force of the preset magnitude is from about 2 pounds to about 3 pounds. This preset magnitude of force is approximately an order of magnitude greater than the magnitude of the force (0.25 pounds to 0.5 pounds) applied to the needle assembly 830 when piercing the patient's skin during injection. After the first and second opposing deformable tabs 841, 842 have plastically deformed, the needle assembly 830 can move freely longitudinally relative to the needle latch assembly 840.

[0040] The needle latch assembly 840 can be formed by punching and / or cutting out a disk-shaped body from a metal sheet. The various openings (i.e., the smaller opening 843, the larger opening 845, and the "H"-shaped opening 844) can also be created by punching out the disk-shaped body or making cuts in the disk-shaped body to form the first and second opposing deformable tabs 841, 842. Thus, the needle latch assembly 840 can be formed as a single structure, thereby minimizing the complexity of manufacturing / assembly.

[0041] Figures 15A - 15D show a flat disk-shaped needle latch assembly 1540 according to some other embodiments. The needle latch assembly 1540 is similar to the needle latch assembly 840 shown in FIGS. 12A and 12B. For example, the needle latch assembly 1540 has first and second opposing deformable tabs 1541, 1542, larger and smaller openings 1545, 1543, and an "H"-shaped opening 1544. The first difference is that the needle latch assembly 1540 includes a side opening 1546 on the side opposite the larger opening 1545 of the disk-shaped body. The side opening 1546 is connected to the "H"-shaped opening and the outside of the disk-shaped body. The second difference is that the needle latch assembly 1540 includes an elastically deformable section 1547 on the side opposite the side opening 1546, adjacent to the larger opening 1545.

[0042] The side opening 1546 and the elastically deformable section 1547 can open the needle latch assembly 1540 by elastically deforming the elastically deformable section 1547 within the plane of the disc-shaped body to increase the size of the side opening 1546' (see FIGS. 15C and 15D). By increasing the size of the side opening 1546', during manufacturing / assembly, the needle latch assembly 1540 can be slid onto a needle assembly (not shown) through the enlarged side opening 1546'.

[0043] Alternatively, the needle latch assembly 1540 can be opened by elastically deforming the elastically deformable section 1547 out of the plane of the disc-shaped body to increase the size of the side opening 1546' (see FIGS. 16C and 16D). By increasing the size of the side opening 1546', during manufacturing / assembly, the needle latch assembly 1540 can be slid onto a needle assembly (not shown) through the enlarged side opening 1546'.

[0044] The needle latch assembly 1540 can be formed by punching and / or cutting out a disc-shaped body from a metal sheet. Various openings (i.e., large and small openings 1545, 1543, the "H"-shaped opening 1544, and the side opening 1546) can also be made by punching the disc-shaped body or making cuts in the disc-shaped body to form the first and second opposing deformable tabs 1541, 1542. Thus, the needle latch assembly 1540 can be formed as a single structure, thereby minimizing the complexity of manufacturing / assembly.

[0045] Exemplary 3D disk-shaped needle latch assembly FIGS. 17A - 21B show a three-dimensional ("3D") disc-shaped needle latch assembly 1740 and its incorporation into needle hub assemblies and safety injection systems according to various embodiments.

[0046] Figures 17A - 17D show a needle latch assembly 1740 according to some embodiments. The needle latch assembly 1740 is a 3D disk-shaped needle latch assembly including an upper flat disk-shaped body 1770, a lower flat disk-shaped body 1772, and a plurality (e.g., four) of coupling members 1774 coupled to the upper and lower flat disk-shaped bodies 1770, 1772. The coupling members 1774 provide a space 1776 between the upper and lower flat disk-shaped bodies 1770, 1772 such that the needle latch assembly 1740 has a 3D disk shape. The lower flat disk-shaped body 1772 includes a downward gasket backup surface 1773 configured to provide a flat surface for compression of a deformable seal member / gasket 1750 (see FIGS. 19A and 19B).

[0047] The upper flat disk-shaped body 1770 is identical to the needle latch assembly 840 shown in FIGS. 12A and 12B. Thus, the upper flat disk-shaped body 1770 is a flat disk-shaped body. The upper flat disk-shaped body 1770 includes first and second opposing deformable tabs 1741, 1742. The first and second opposing deformable tabs 1741, 1742 are asymmetric, and their opposing edges partially define a smaller opening 1743 located approximately at the center of the flat disk-shaped body. Also, the upper flat disk-shaped body 1770 includes an "H"-shaped opening 1744 partially defined by the first and second opposing deformable tabs 1741, 1742.

[0048] Near the center of one of the long legs of the "H"-shaped opening 1744, a larger opening 1745 is formed. The larger opening 1745 is disposed eccentrically with respect to the center of the flat disk-shaped body. The larger opening 1745 is sized and shaped such that a needle assembly (not shown) can pass through. On the other hand, the smaller opening 1743 is sized and shaped to prevent a needle assembly (not shown) from passing longitudinally.

[0049] The first and second opposing deformable tabs 1741, 1742 are configured to plastically deform when a force of a preset magnitude is applied proximally to the tabs 1741, 1742. In some embodiments, the force of the preset magnitude is from about 2 pounds to about 3 pounds. This force of the preset magnitude is approximately an order of magnitude greater than the magnitude of the force (from 0.25 pounds to 0.5 pounds) applied to the needle assembly 1730 when piercing the patient's skin during injection. After the first and second opposing deformable tabs 1741, 1742 have plastically deformed, the needle assembly 1730 can move freely longitudinally relative to the upper flat disk-shaped body 1770.

[0050] The lower flat disk-shaped body 1772 has an oval opening 1780. When the upper and lower flat disk-shaped bodies 1770, 1772 are coupled by a plurality of coupling members 1774, the oval opening 1780 is aligned with both the smaller opening 1743 and the larger opening 1745 defined in the upper flat disk-shaped body 1770. Thus, the oval opening 1780 defined in the lower flat disk-shaped body 1772 enables insertion of a needle assembly (not shown) through the needle latch assembly 1740.

[0051] Figures 18A and 18B show a needle latch assembly 1740 attached to a needle assembly 1730 having a deformable seal member / gasket 1750 on the proximal side. As shown in Figure 18A, the space 1776 formed by the plurality of coupling members 1774 prevents the deformable seal member 1750 from contacting the upper flat disk-shaped body 1770. Thus, the seal member 1750 does not prevent the plastic deformation of the first and second opposing deformable tabs 1741, 1742 of the upper flat disk-shaped body 1770.

[0052] Figures 19A and 19B illustrate a safety injection system 1700 according to some embodiments. Figures 19A and 19B illustrate the safety injection system 1700 in a configuration that is ready for use upon assembly. Figures 19A and 19B provide views similar to Figures 8A and 8B, and corresponding reference numerals are used for similar components. One difference between the two safety injection systems 1700, 800 is that the safety injection system 1700 includes a 3D needle latch assembly 1740, and thus includes a larger space within the needle hub assembly 1710 to accommodate the larger 3D needle latch assembly 1740.

[0053] Figures 20A and 20B illustrate the safety injection system 1700 in two exploded views similar to Figures 9A and 9B, and corresponding reference numerals are used for similar components. Figures 21A and 21B illustrate the safety injection system 1700 in two further exploded views similar to Figures 10A and 10B, and corresponding reference numerals are used for similar components. The difference between the safety injection systems 1700, 800 is that the safety injection system 800 has a flat needle latch assembly 840, whereas the safety injection system 1700 has a 3D needle latch assembly 1740. The 3D needle latch assembly 1740 requires a larger space within the needle hub assembly 1710 of the safety injection system 1700. However, the space 1776 for the 3D needle latch assembly 1740 prevents the seal member 1750 from interfering with the plastic deformation of the first and second opposing deformable tabs 1741, 1742 of the upper flat disk-shaped body 1770, and thus the 3D needle latch assembly 1740 provides more robustness in latch release.

[0054] Figures 20A - 21B illustrate the deformable seal member 1750 in a non-compressed / relaxed state. Figures 19A and 19B illustrate the deformable seal member 1750 in a compressed / biased state.

[0055] The needle latch assembly 1740 can be formed by punching and / or cutting out an upper and a lower disk-shaped body 1770, 1772 and a connecting member 1774 from a metal sheet. Thereafter, the upper and lower disk-shaped bodies 1770, 1772 and the connecting member 1774 are bent and joined (e.g., welded) to form the 3D needle latch assembly 1740. Various openings (i.e., the smaller opening 1743, the larger opening 1745 and the "H"-shaped opening 1744) can be made by punching out the upper disk-shaped body or making incisions in the upper disk-shaped body to form the first and second opposing deformable tabs 1741, 1742. The oval opening 1780 can further be made by punching out the lower disk-shaped body or making incisions in the lower disk-shaped body. Thus, the needle latch assembly 1740 can be formed as a single structure, thereby minimizing the manufacturing / assembly complexity.

[0056] Exemplary needle latch assembly having a color Figures 22A - 22C show a 3D needle latch assembly 2240 having a needle collar 2260 according to various embodiments. The needle latch assembly 2240 includes a rectangular prism holding portion 2250, a cylindrical needle collar portion 2260, and a connecting portion 2270 that couples the cylindrical needle collar portion 2260 to the rectangular prism holding portion 2250.

[0057] The rectangular prism holding portion 2250 is sized and shaped to fit snugly within a chamber defined within a needle hub assembly (not shown). The rectangular prism holding portion 2250 also includes a pair of outwardly biased tabs 2252 that allow the holding portion 2250 to be inserted into the chamber of the needle hub assembly but prevent the holding portion 2250 from being removed from the chamber of the needle hub assembly. The rectangular prism holding portion 2250 is a rectangular box formed by bending each of the two ends of a strip (e.g., metal) at right angles twice until the free ends of the strip meet.

[0058] The cylindrical needle collar portion 2260 is formed by winding a sheet (e.g., metal) 2 until its two free ends almost meet, forming a cylinder having a longitudinal opening 2262. The cylindrical needle collar portion 2260 is plastically deformable. Thus, the cylindrical needle collar portion 2260 can be plastically opened at the longitudinal opening 2262 and crimped to the needle assembly 2230 (FIG. 23A). When the cylindrical needle collar portion 2260 is crimped / bonded to the needle assembly 2230, the needle assembly 2230 is restrained from moving longitudinally relative to the needle latch assembly 2240. Applying a force in the proximal direction of a preset magnitude to the cylindrical needle collar portion 2260 (via the needle assembly 2230) causes the longitudinal opening 2262 to expand, plastically deforming the cylindrical needle collar portion 2260 and causing the needle assembly 2230 to disengage from the needle latch assembly 2240 (FIG. 23B). In some embodiments, the force in the proximal direction is from about 2 pounds to about 3 pounds. FIGS. 23A and 23B show a needle assembly 2230 having a notch, but the needle latch assembly 2240 would function similarly with a notchless needle assembly.

[0059] The needle latch assembly 2240 can be formed by punching and / or cutting out a rectangular prism retaining portion 2250, a cylindrical needle collar portion 2260, and a coupling member 2270 from a metal sheet. Thereafter, the various components of the rectangular prism retaining portion 2250, the cylindrical needle collar portion 2260, and the coupling member 2270 are folded and joined (e.g., welded) as needed to form the needle latch assembly 2240. Thus, the needle latch assembly 2240 can be formed as a single structure, thereby minimizing manufacturing / assembly complexity.

[0060] Exemplary three-dimensional needle latch assembly having a floating tab FIGS. 24A - 28B show a 3D needle latch assembly 2440 having a "floating tab" 2441 and its incorporation into needle hub assemblies and safety injection systems according to various embodiments.

[0061] Figures 24A-24D illustrate a needle latch assembly 2440 according to some embodiments. The needle latch assembly 2440 is a 3D needle latch assembly that includes a flat rectangular body 2472, first and second arms 2474, and first and second pairs of standoffs 2470 formed at respective ends of the first and second arms 2474 on a side opposite the flat rectangular body 2472. The flat rectangular body 2472, the first and second arms 2474, and the first and second pairs of standoffs 2470 define a cage in which the flat rectangular body 2472 and the first and second pairs of standoffs 2470 are disposed at opposite ends. The first and second arms 2474 have respective arcuate axial cross-sections that curve toward each other and are configured such that when disposed within corresponding circular chambers, the first and second arms 2474 form part of a cylinder so that the needle latch assembly 2440 is rotatable (see FIGS. 26A and 26B).

[0062] The flat rectangular body 2472 may be configured to interfere with an internal shoulder within the needle hub assembly 2410 (see FIGS. 26A and 26B) to limit distal movement of the needle latch assembly 2440 relative to the needle hub assembly 2410. The flat rectangular body 2472 is also a bottom-facing gasket backstop surface 2473 configured to provide a flat surface for compression of a deformable seal member / gasket 2450 (see FIGS. 26A and 26B). As shown in FIGS. 27A and 27B, the needle assembly 2430 includes a distal shoulder 2434 that interferes with a proximal shoulder 2412 formed on an inner surface of the needle hub assembly 2410 to also limit distal movement of the needle assembly 2430 relative to the needle hub assembly 2410. FIGS. 26A and 26B show the distal shoulder 2434 of the needle assembly 2430 abutting the proximal shoulder 2412 of the needle hub assembly 2410 to limit distal movement of the needle assembly 2430 relative to the needle hub assembly 2410.

[0063] The first and second arms 2474 are orthogonal to the plane of the flat rectangular body 2472. Each hinge formed where the first and second arms 2474 are coupled to the plane of the flat rectangular body 2472 is elastically deformable. As a result, when the needle latch assembly 2440 is disposed within a corresponding circular chamber (see FIGS. 26A and 26B) having a diameter slightly smaller than the diameter of the needle latch assembly 2440, the first and second arms 2474 can be biased radially outward to hold the needle latch assembly 2440 within the circular chamber. Also, the first and second arms 2474 can open during assembly to allow insertion of the needle assembly 2430 through the smaller opening 2443 defined thereby. After assembly, the circular chamber prevents the first and second arms 2474 from opening.

[0064] The first and second arms 2474 are elastically deformable in a pre-assembled state but not in an assembled state. Thus, when the needle latch assembly 2440 is attached to the needle assembly 2430 during assembly of the safety injection system 2400, the first and second arms 2474 elastically deform to open the smaller opening 2443. After injection is complete, the first and second arms 2474 cannot deform to release the needle assembly 2440. However, when a sufficient proximally-directed pulling force is applied, the first and second tabs 2441 can freely plastically deform, as described herein, to pull the needle assembly 2430 into the syringe body 2420 to release the needle assembly 2440 from the needle latch assembly 2440.

[0065] As shown in FIG. 24C, the first and second tabs 2441 extend orthogonally from the first and second arms 2474, respectively, toward each other. The first and second tabs 2441 are substantially symmetric, and their opposing edges partially define the smaller opening 2443, which is located substantially at the center of the plane in which the first and second tabs 2441 extend toward each other. The flat rectangular body 2472 defines the larger opening 2445 at its substantially center. The smaller opening and the larger opening are aligned / coaxial along the axis of the needle assembly 2430 to which the needle latch assembly 2440 is attached (see FIGS. 26A and 26B).

[0066] The first and second tabs 2441 are configured to plastically deform when a force of a preset magnitude is applied to the tabs 2441 in the proximal direction. In some embodiments, the preset magnitude of the force is from about 2 pounds to about 3 pounds. This preset magnitude of the force is approximately an order of magnitude greater than the magnitude of the force (0.25 pounds to 0.5 pounds) applied to the needle assembly 2430 when piercing the patient's skin during injection. After the first and second tabs 2441 plastically deform, the needle assembly 2430 is free to move longitudinally relative to the needle latch assembly 2440.

[0067] As shown in FIGS. 24C and 27A, the first and second pairs of standoffs 2470 are bent toward each other. In this way, the standoffs 2470 guide the needle latch assembly 2440 into the chamfered opening into the chamber formed in the needle hub assembly 2410 during the assembly of the safety injection system 2400.

[0068] As described above, the flat rectangular body 2472, the first and second arms 2474, and the first and second pairs of standoffs 2470 define a cage in which the flat rectangular body 2472 and the first and second pairs of standoffs 2470 are disposed at opposite ends. As shown in FIG. 24C, the first and second tabs 2441 extend orthogonally from the first and second arms 2470, respectively, between the flat rectangular body 2472 and the first and second pairs of standoffs 2470 in the space 2476 defined by the cage. For this reason, the first and second tabs 2441 are configured to engage and disengage from the needle assembly 2430 while remaining inside the cage (see FIGS. 26A and 26B). Since the first and second tabs 2441 are disposed in the space 2476, they are referred to as "floating tabs". Therefore, the interior of the needle hub assembly 2410 and the deformable seal member 2450 do not interfere with the first and second tabs 2441 and their interaction with the needle assembly 2430. By protecting the floating tabs 2441 inside the cage, the needle holding force can be made independent of the force applied to the needle latch assembly 2440 during assembly of the safety injection system 2400, which often varies. Also, by protecting the floating tabs 2441 inside the cage, the needle holding force can be made independent of the geometry of the deformable seal member 2450 and the tolerances of the various components within the assembly. In fact, the cage formed by the flat rectangular body 2472, the first and second arms 2474, and the first and second pairs of standoffs 2470 reacts to remove / absorb the compressive forces from the needle hub assembly 2410 and the deformable seal member 2450 during assembly.

[0069] FIGS. 25A and 25B show a needle latch assembly 2440 attached to a needle assembly 2430 having a deformable seal member 2450 on the proximal side. As shown in FIG. 25A, the space 2476 within the cage prevents the deformable sealing member 2450 from contacting the first and second tabs 2441. For this reason, the seal member 2450 does not prevent plastic deformation of the first and second tabs 2441.

[0070] Figures 26A and 26B illustrate a safety injection system 2400 according to some embodiments. Figures 26A and 26B illustrate the safety injection system 2400 in an assembled and ready-to-use configuration. Figures 26A and 26B provide views similar to Figures 8A and 8B, and corresponding reference numerals are used for similar components. One difference between the two safety injection systems 2400, 800 is that the safety injection system 2400 includes a 3D needle latch assembly 2440, and thus includes a larger chamber within the needle hub assembly 2410 to accommodate the larger 3D needle latch assembly 2440.

[0071] As shown in Figure 26A, the space 2476 within the cage prevents the proximal inner wall 2414 of the needle hub assembly 2410 from contacting the first and second tabs 2441. Thus, the needle hub assembly 2410 does not prevent plastic deformation of the first and second tabs 2441.

[0072] Figures 27A and 27B illustrate the safety injection system 2400 in two exploded views similar to Figures 9A and 9B, and corresponding reference numerals are used for similar components. Figures 28A and 28B illustrate the safety injection system 2400 in two further exploded views similar to Figures 10A and 10B, and corresponding reference numerals are used for similar components. The difference between the safety injection systems 2400, 800 is that the safety injection system 800 has a flat needle latch assembly 840, while the safety injection system 2400 has a 3D needle latch assembly 2440. The 3D needle latch assembly 2440 requires a larger chamber in the needle hub assembly 2410 of the safety injection system 2400. However, the space 2476 of the 3D needle latch assembly 2440 prevents the seal member 2450 and the needle hub assembly 2410 from interfering with plastic deformation of the first and second tabs 2441 on the upper flat disk-shaped body 2470, and thus the 3D needle latch assembly 2440 provides more robustness for unlatching.

[0073] Figures 27A - 28B show the deformable seal member 2450 in the uncompressed / relaxed state. Figures 26A and 26B show the deformable seal member 2450 in the compressed / biased state.

[0074] The needle latch assembly 2440 can be formed by punching and / or cutting out a flat rectangular body 2472, first and second arms 2474, first and second pairs of standoffs 2470, and first and second tabs 2441 from a metal sheet. Thereafter, the first and second tabs 2441, first and second pairs of standoffs 2470, and first and second arms are folded / bent to form the 3D needle latch assembly 2440. The smaller opening 2443 and the larger opening 2445 can be punched out from the flat rectangular body 2472 or cut into the flat rectangular body. Thus, the needle latch assembly 2440 can be formed as a single structure, thereby minimizing the manufacturing / assembly complexity.

[0075] All of the needle latch assemblies 840, 1540, 1740, 2240 disclosed herein can be formed by punching and / or cutting out from a metal sheet and, if necessary, folding and / or joining (e.g., welding) to form the needle latch assemblies 840, 1540, 1740, 2240. Thereby, the manufacturing / assembly complexity is minimized and the manufacturing / assembly process becomes more suitable for automation. The needle latch assemblies 840, 1540, 1740, 2240 are configured to release the latch by applying a force of 2 to 3 pounds in the proximal direction, which is approximately one order of magnitude greater than the magnitude of the force (0.25 to 0.5 pounds) applied to the needle assembly 830 when piercing the patient's skin during injection. Also, the needle latch assemblies 840, 1540, 1740, 2240 reduce the number of parts, thereby enhancing the robustness of needle latch release and providing a more robust needle retraction type safe injection system and method.

[0076] Various exemplary embodiments of the present invention are described herein. These examples are referred to in a non-limiting sense. They are provided to illustrate more broadly applicable aspects of the present invention. Various changes can be made to the described invention and it can be replaced with equivalents without departing from the true spirit and scope of the present invention. Further, many changes can be made to adapt a particular situation, material, composition of matter, process, process act or step to the objectives, spirit or scope of the present invention. Further, as will be understood by those skilled in the art, each of the individual variations described and illustrated herein can be readily separated from, or combined with, any of the features of some other embodiments without departing from the scope or spirit of the present invention. All such changes are intended to be within the scope of the claims related to this disclosure.

[0077] Any of the devices described for performing a diagnostic or interventional procedure on a subject may be provided in a packaged combination for use in performing such an intervention. Those supply "kits" may further include instructions for use and may be packaged in a sterile tray or container as generally employed for such purposes.

[0078] The present invention includes methods that can be performed using a device of interest. The method can include the act of providing such a suitable device. Such providing may be performed by an end user. That is, the act of "providing" simply requires the end user to perform an act of obtaining, accessing, approaching, placing, setting up, activating, powering on or other act to provide the necessary device in the method of interest. The methods described herein can perform the described events in any logically possible order or in the order of the described events.

[0079] Exemplary aspects of the present invention have been described above, along with details regarding material selection and fabrication. Other details of the present invention can be understood not only in relation to the previously cited patents and publications, but are generally known or understandable to those of ordinary skill in the art. For example, those of ordinary skill in the art will understand that one or more lubricious coatings (e.g., hydrophilic polymers such as polyvinylpyrrolidone-based compositions, fluoropolymers such as tetrafluoroethylene, PTFE, hydrophilic gels or silicones) can be used, as needed, in connection with various parts of the device, such as relatively large interfacial surfaces of movably coupled parts, thereby, for example, facilitating low friction operation or advancement of such objects relative to other parts of the instrument or nearby tissue structures. The same will apply to aspects based on the methods of the present invention with respect to additional acts generally or logically employed.

[0080] Furthermore, although the present invention has been described with reference to several examples incorporating various features, it is not limited to what has been described or disclosed as contemplated for each variation of the present invention. Various changes can be made to the described invention without departing from the true spirit and scope of the present invention, and equivalents can be substituted therefor (whether or not described herein or not included for brevity). Additionally, when ranges of values are provided, it is to be understood that all intervening values between the upper and lower limits of that range, as well as other described values or intervening values within the described range, are encompassed within the scope of the present invention.

[0081] Moreover, any feature of the described variations of the present invention is intended to be described and claimed independently or in combination with any one or more of the features described herein. References to singular items include the possibility that there may be more than one of the same item. More specifically, as used in this specification and the claims related thereto, the singular forms "a", "an", "said", and "the" include plural referents unless specifically stated otherwise. In other words, the use of the articles enables "at least one" of the subject items in the above description, as well as in the claims related to this disclosure. Note that such claims may be drafted to exclude any element. For this reason, this description is intended to function as a prior description for using exclusive terms such as "alone", "only", etc. in relation to the listing of claim elements, or for using "negative" limitations.

[0082] Without using such exclusive terms, the term "comprising" in the claims related to this disclosure shall be taken to enable any additional element, whether or not a given number of elements are listed in such claims, or whether the addition of a feature is considered to change the nature of the elements described in such claims. Unless specifically defined herein, all technical and scientific terms used herein shall be given the broadest generally understood meaning possible while maintaining the validity of the claims.

[0083] The scope of the present invention is not limited to the provided examples and / or the specification of the subject matter, but rather is limited only by the scope of the language of the claims related to this disclosure.

Claims

1. A syringe assembly comprising: A syringe body having a syringe interior, a longitudinal axis, a proximal end and a distal end, and a needle attachment interface disposed at the distal end thereof; A needle assembly having a proximal end and a distal end; A retaining clip having a retaining barb that engages the distal end of the syringe body, the retaining clip being configured to prevent the needle hub from moving distally relative to the syringe body; A gasket compressed to provide a liquid-tight seal around the outer diameter of the needle assembly and at the distal end of the syringe body, the gasket being configured to prevent liquid from passing between the needle assembly, the gasket, and the distal end of the syringe body; A needle latch assembly comprising a flat disk-shaped body having opposing first and second latch tabs, the first and second latch tabs being plastically deformable; A cylindrical needle hub that houses the needle latch assembly, the gasket, the retaining clip, and the distal end of the syringe body therein, the cylindrical needle hub having a plurality of inner surfaces, the plurality of inner surfaces being configured to abut at least a portion of the flat disk-shaped body of the needle latch assembly, an outer peripheral surface of the gasket, and a portion of the retaining clip, respectively, to maintain a sealed configuration during injection using the syringe assembly and to prevent liquid from leaking out of the exterior of the needle hub; The syringe assembly, wherein the needle assembly is configured such that when the needle assembly is pulled proximally after injection using the syringe assembly, the first and second latch tabs are plastically deformed to disengage from the needle assembly, and the needle assembly can be at least partially retracted into the syringe body.

2. The syringe assembly according to claim 1, wherein The first and second latch tabs are plastically deformable from a closed configuration to an open configuration.

3. The syringe assembly according to claim 2, wherein The first and second latch tabs are configured to plastically deform when a proximally directed force of 1 to 5 pounds is applied.

4. The syringe assembly according to claim 1, wherein A syringe assembly, characterized in that the first and second latch tabs are asymmetric.

5. In the syringe assembly according to claim 1, the needle latch assembly defines a smaller opening and a larger opening, the larger opening is sized and shaped to allow the needle assembly to pass through, the smaller opening is sized and shaped to prevent the needle assembly from passing through until the first and second latch tabs are deformed. A syringe assembly characterized by that.

6. In the syringe assembly according to claim 5, the larger opening is disposed eccentrically from the center of the flat disk-shaped body. A syringe assembly characterized by that.

7. In the syringe assembly according to claim 5, the smaller opening is disposed at the center of the flat disk-shaped body. A syringe assembly characterized by that.

8. In the syringe assembly according to claim 5, the flat disk-shaped body is also provided with an "H"-shaped opening. A syringe assembly characterized by that.

9. In the syringe assembly according to claim 8, a side opening is also defined on the flat disk-shaped body on the opposite side of the larger opening, and this side opening is connected to the "H"-shaped opening and the outside of the flat disk-shaped body. A syringe assembly characterized by that.

10. In the syringe assembly according to claim 9, the flat disk-shaped body also has an elastically deformable section disposed adjacent to the larger opening and on the opposite side of the side opening. A syringe assembly characterized by that.

11. In the syringe assembly according to claim 10, the flat disk-shaped body is configured to elastically deform in the plane of the flat disk-shaped body by the elastically deformable section to expand the side opening. A syringe assembly characterized by that.

12. In the syringe assembly according to claim 10, the flat disk-shaped body is configured to elastically deform out of the plane of the flat disk-shaped body by the elastically deformable section to expand the side opening. A syringe assembly characterized by that.

13. In the syringe assembly according to claim 1, The syringe assembly, wherein the flat disk-shaped body is punched out or cut from a metal sheet.

14. In the syringe assembly according to claim 1, The syringe assembly, wherein the first and second latch tabs are configured not to plastically deform during injection using the syringe assembly.

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