Fixing device of back skin dressing for experimental animal

Abstract

The utility model provides a fixing device of a back skin dressing for an experimental animal, which comprises a flexible bearing base, the flexible bearing base comprises an annular rubber frame, and a medical polyurethane film is fixed on the inner circumference of the rubber frame; the protective mechanism is detachably covered on the medical polyurethane film; the main fixing belts are symmetrically arranged on the left side face and the right side face of the flexible bearing base, the notches are symmetrically formed in the front end face of the flexible bearing base, the hook-and-loop fasteners are arranged at the ends of the main fixing belts, the auxiliary fixing belts are arranged on the edges of the main fixing belts, and the other ends of the auxiliary fixing belts are connected to the edge of the flexible bearing base. And the main fixing band and the auxiliary fixing band form an adjustable Y-shaped forked structure. The whole structure of the fixing device integrates operation convenience and animal welfare, the fixing device is particularly suitable for animal experiment scenes needing long-term fixing and frequent dressing replacement, the fixing effect of the whole fixing device is good, and the whole fixing device cannot move due to animal movement.

Description

Technical Field

[0001] This utility model relates to a fixation device for a back skin dressing for laboratory animals. Background Technology

[0002] In biomedical research, animal models of skin trauma (such as rats and mice) are widely used in wound healing, drug evaluation, and dressing performance testing. To ensure the accuracy and reproducibility of experimental results, dressings must stably cover the wound and prevent them from falling off or shifting due to scratching or friction by the animal. However, existing dressing fixation methods have many limitations, restricting the reliability and ease of operation of experiments.

[0003] In the prior art, patent number CN602460287722.9 describes an animal back skin drug delivery fixation device that uses Velcro to secure the dressing. While this achieves a fixation effect, the adhesion between the Velcro and the felt may loosen after animal activity (such as rubbing or rolling), causing the dressing to shift. Therefore, this invention addresses these shortcomings by designing a fixation device that prevents dressing shifting during animal activity, provides a good fixation effect, and facilitates easy fixation. Utility Model Content

[0004] This invention provides a fixation device for a back skin dressing for laboratory animals, which can effectively solve the above-mentioned problems.

[0005] This utility model is implemented as follows:

[0006] A fixation device for a back skin dressing for laboratory animals, comprising a flexible support base.

[0007] The flexible bearing base includes an annular rubber frame, and a medical polyurethane film is fixed to the inner periphery of the rubber frame;

[0008] A removable protective structure covering the medical polyurethane film;

[0009] The main fixing straps are symmetrically arranged on the left and right sides of the flexible bearing base, and the slots are symmetrically formed on the front end face of the flexible bearing base. The Velcro is provided at the end of the main fixing straps, and the secondary fixing straps are provided at the edge of the main fixing straps. The other end of the secondary fixing straps is connected to the edge of the flexible bearing base, so that the main fixing straps and the secondary fixing straps form an adjustable Y-shaped bifurcated structure.

[0010] The beneficial effects of this utility model are:

[0011] (1) This utility model, through the design of the annular rubber frame and medical polyurethane film of the flexible bearing base, can not only closely fit the curve of the animal's back but also maintain good flexibility, effectively reducing skin pressure damage; its unique adjustable Y-shaped bifurcated fixation structure works in concert with the main fixation strap and the secondary fixation strap, and can quickly adjust the tightness through Velcro, which can not only provide a stable circumferential fixation force to resist the twisting and friction during the animal's movement, but also disperse pressure through the elastic secondary strap to avoid local tissue ischemia, significantly improving the stability and comfort of dressing fixation; at the same time, the design of the detachable protective mechanism facilitates dressing replacement and wound observation. The overall structure takes into account both operational convenience and animal welfare, and is particularly suitable for animal experimental scenarios that require long-term fixation and frequent dressing replacement. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is the front view of Embodiment 1.

[0014] Figure 2 This is a schematic diagram of the back structure of the main fixing strap in Embodiment 1.

[0015] Figure 3 This is a schematic diagram showing the connection of the flexible bearing base, the reserved frame, and the magnetic frame in Embodiment 1.

[0016] Figure 4 This is a schematic diagram of the dressing in Example 1.

[0017] Figure 5 This is a schematic diagram of the fixing mechanism in Embodiment 2.

[0018] Figure 6 This is a schematic diagram of the structure of Embodiment 3.

[0019] Explanation of icon numbers:

[0020] 10. Flexible load-bearing base; 10-0. Groove; 100. Annular rubber frame; 102. Medical polyurethane film;

[0021] 20. Main securing strap; 200. Velcro; 202. Secondary securing strap;

[0022] 60. Fixing mechanism; 600. Positioning ring; 602. Flexible fixing strap; 6020. Head; 6022. Tail; 604. Locking hole; 606. Locking ring; 608. Alloy frame; 610. Locking buckle;

[0023] 30. Pre-fixing strap; 300. Ventilation holes;

[0024] 40. Reserved frame; 400. Dressing; 4002. Absorbent and water-locking layer; 4004. Waterproof and stain-resistant layer;

[0025] 50. Magnetic border. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely to represent selected embodiments of this utility model.

[0027] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] Example 1

[0029] Reference Figure 1-4As shown, a fixation device for a back skin dressing for laboratory animals includes a flexible support base 10, main fixation straps 20 symmetrically arranged on the left and right sides of the flexible support base 10, grooves 10-0 symmetrically formed on the front end face of the flexible support base 10 (so that they can be used in conjunction with the main fixation straps 20 and the secondary fixation straps 202), Velcro 200 provided at the end of the main fixation straps 20, and secondary fixation straps 202 provided at the edge of the main fixation straps 20. The other end of the secondary fixation straps 202 is connected to the edge of the flexible support base 10, so that the main fixation straps 20 and the secondary fixation straps 202 form an adjustable Y-shaped bifurcated structure. Specifically, the main fixing strap 20 and the secondary fixing strap 202 are made of nylon webbing (the nylon main strap provides high-strength fixation, while the elastic spandex secondary strap allows for moderate stretching, maintaining tension while avoiding excessive restraint, adapting to the chest and abdomen rise and fall of the mouse during breathing) and elastic spandex blended strap (the elasticity of the elastic spandex blended secondary strap reduces friction against the skin, while the nylon main strap ensures that it is not easily deformed during long-term use, balancing comfort and durability).

[0030] The main fixation strap 20 laterally encircles the animal's torso, while the secondary fixation strap 202 diagonally tightens the edge of the flexible support base 10, creating multi-angle force distribution. This structure effectively resists longitudinal (e.g., scratching) and lateral (e.g., rolling) displacements during activity, preventing the dressing 400 from falling off due to animal twisting. Furthermore, the Velcro 200 design allows for quick adjustment of the main fixation strap 20's tightness to accommodate animals of different sizes. The secondary fixation strap 202 automatically compensates for tension changes during activity through elasticity, preventing excessive tightness leading to skin ischemia or excessive looseness causing dressing 400 displacement. Moreover, the Y-shaped bifurcation opening angle can be adjusted according to the curvature of the mouse's back, ensuring that the central area of ​​the dressing 400 (e.g., directly above the wound) is always evenly compressed, reducing edge lifting. Simultaneously, the secondary fixation strap 202 distributes some of the tension to the edge of the flexible support base 10, preventing circumferential pressure on the mouse's chest and abdomen when the main fixation strap 20 is used alone, thus reducing stress response.

[0031] Therefore, the Velcro 200, combined with its Y-shaped bifurcated structure, only requires adjustment on one side to achieve fixation during operation, making it suitable for experimental scenarios where dressings need to be changed frequently and reducing reliance on anesthesia.

[0032] It should be noted that for smaller animals, the forking ratio may need to be further reduced to ensure stability; this can be adjusted according to the actual situation.

[0033] The flexible support base 10 is also provided with a pre-fixation band 30, on which multiple ventilation holes 300 are formed. The pre-fixation band 30 serves as a temporary fixation device before the flexible fixation band 602 is tightened, preventing the dressing 400 from shifting. This is particularly suitable for initial fixation during animal activity, and also reduces friction and irritation to the animal's skin caused by repeated adjustments of the flexible fixation band 602. Furthermore, the distribution design of the ventilation holes 300 (pore diameter 0.5-1mm) balances adhesion and breathability, preventing skin stuffiness due to complete sealing. Moreover, the ventilation holes 300 form air convection channels, accelerating sweat evaporation and reducing the risk of skin maceration (especially suitable for long-term experiments).

[0034] Specifically, the pre-fixation band 30 is made of a breathable material (such as medical elastic fabric), and the design of the vent 300 can further improve the moisture permeability to ≥1000g / m2 / 24h. Specifically, a medical silicone slow-release layer (containing 0.1% lidocaine) can be coated around the vent 300 to reduce itching when animals wear it.

[0035] The flexible support base 10 includes an annular rubber frame 100, and a medical polyurethane film 102 is fixed to the inner periphery of the rubber frame 100.

[0036] Specifically, the thickness of the medical polyurethane film 102 is 0.1-0.3 mm; in one embodiment, to verify the comprehensive performance of medical polyurethane films of different thicknesses (0.1 mm, 0.2 mm, 0.3 mm) in experimental animal dressing fixation devices, the optimal thickness parameters are determined as follows:

[0037] Experimental materials

[0038] Group Thickness (mm) Material Number of test samples Experimental group 1 0.1 Medical grade polyurethane n＝15 Experimental group 2 0.2 Medical grade polyurethane n＝15 Experimental group 3 0.3 Medical grade polyurethane n＝15 control group none Ordinary PE film n＝5

[0039] Experimental methods (mechanical property testing)

[0040] Tested using a universal testing machine (ISO 527 standard):

[0041] Tensile strength (MPa); Elongation at break (%); Tear resistance (N / cm)

[0042] Animal compatibility test (SD rats (weight 280g±60g) were used)

[0043] After shaving the back, a fixation device is installed.

[0044] Observation indicators: fit score (1-5 points); incidence of skin compression; animal freedom of movement score.

[0045] Moisture permeability test (using the cup method (ASTM E96))

[0046] Temperature 37℃±1℃; relative humidity 50%±5%; test 24h moisture permeability (g / m2 / 24h).

[0047] Durability test

[0048] Simulated experimental conditions:

[0049] Apply 0.5 Hz cyclic stress (0-5 N) daily; soak in physiological saline for 6 hours / day; record the number of cycles in which damage occurs.

[0050] Experimental results

[0051] Table 1 Comparison of Mechanical Properties

[0052] Thickness (mm) Tensile strength (MPa) Elongation at break (%) Tear resistance (N / cm) 0.1 15.2±1.3 380±25 42±3.5 0.2 60.8±1.8 460±30 53±4.2 0.3 25.6±2.1 350±28 65±5.0

[0053] Table 2 Animal Experiment Data

[0054] Thickness (mm) Fit rating Incidence of compression (%) Activity Freedom Rating 0.1 3.8±0.4 6.7 4.2±0.3 0.2 4.5±0.3 2.1 4.0±0.2 0.3 3.2±0.5 15.3 3.1±0.4

[0055] Table 3 Functional Performance Tests

[0056] Thickness (mm) Moisture permeability (g / m2 / 24h) Breakage cycle (times) 0.1 3850±610 360±25 0.2 3050±180 580±35 0.3 2250±150 750±40

[0057] Experimental conclusions

[0058] Through systematic testing of medical polyurethane films with thicknesses of 0.1 mm, 0.2 mm, and 0.3 mm, the following conclusion was drawn: a thickness of 0.2 mm is the optimal choice, as it exhibits the best overall performance.

[0059] For short-term experiments (≤7 days): 0.1mm film can be selected to reduce costs, and it has a higher moisture permeability (3850g / m2 / 24h); for large animal or highly active experiments: 0.25-0.3mm thickness is recommended to improve impact resistance (tear resistance ≥65N / cm).

[0060] Furthermore, a magnetic block (not shown in the figure) is embedded inside the rubber frame 100, so that the reserved frame 40 can be clamped and fixed to the flexible support base 10 with the magnetic frame 50, which facilitates the replacement of the dressing 400 later.

[0061] Furthermore, the rubber frame 100 has a Shore hardness of 25-35A (young animals) or 35-45A (adult animals) to prevent animals from biting it.

[0062] Furthermore, the rubber frame 100 and the magnetic frame 50 use neodymium iron boron permanent magnets (N35-N52 grade), and the magnetic attraction force must be ≥0.5N / cm2 to ensure clamping stability. At the same time, the surface of the magnetic block must be nickel-plated or wrapped with a medical-grade silicone layer to avoid long-term contact with bodily fluids and corrosion.

[0063] A removable protective mechanism covering a medical polyurethane film 102; the protective mechanism includes a pre-reserved frame 40 and a dressing 400 disposed on the front end of the pre-reserved frame 40; the dressing 400 includes an absorbent and water-locking layer 4002 and a waterproof and stain-resistant layer 4004 disposed sequentially from top to bottom. The pre-reserved frame 40 is also connected to a magnetic frame 50 to fix the protective mechanism.

[0064] Specifically, the waterproof and stain-resistant layer 4004 is made of waterproof polyurethane (PU) film or TPU-coated nonwoven fabric; the liquid-absorbing and water-locking layer 4002 is made of SAP super absorbent polymer + fiber cloth viscose fiber.

[0065] Among them, the superabsorbent polymer (SAP) content in the 4002 absorbent layer is 30-50%, the absorption rate is ≥15g / g (physiological saline), and the fiber cloth weight is 40-60g / m2.

[0066] Furthermore, a micro-breathable channel (channel density 60-30 / cm2, single channel diameter 50-100μm) is reserved between the liquid-absorbing and water-locking layer 4002 and the waterproof and stain-resistant layer 4004.

[0067] Example 2

[0068] Reference Figure 5 As shown, the difference between this embodiment and Embodiment 1 is that the fixing mechanism 60 includes a pair of positioning rings 600 symmetrically arranged on the front of the flexible bearing base 10, and a flexible fixing band 602 connecting the two positioning rings 600; wherein, the flexible fixing band 602 includes a head 6020 and a tail 6022, a plurality of locking holes 604 arranged along the length direction of the flexible fixing band 602, a locking ring 606 slidably sleeved on the flexible fixing band 602, an alloy frame 608 hinged to the tail 6022, and a rotatably arranged buckle 610.

[0069] Specifically, the positioning ring 600 ensures even force distribution and prevents the dressing 400 from tilting or falling off due to animal movement. Meanwhile, the flexible fixation band 602 uses medical-grade TPU or nylon braided band with moderate elasticity, which can adapt to the deformation of the animal's trunk during breathing and movement, reducing the feeling of restraint. Furthermore, the locking ring 606 can slide along the flexible fixation band 602, and combined with multiple locking holes 604 (spaced 5-10mm), it can achieve fine adjustment of tightness to suit animals of different sizes (such as mice and rats). At the same time, the locking holes 604 adopt an inverted conical structure, and the locking buckle 610 forms a self-locking mechanism after insertion, preventing accidental loosening during the experiment.

[0070] Specifically, the inner side of the flexible fixing strap 602 can be laminated with a soft silicone layer (approximately 0.3mm thick) to prevent friction against the animal's skin.

[0071] Example 3

[0072] Reference Figure 6As shown, the difference between this embodiment and embodiments one and two is that the edge of one of the main fixing straps 20 is not provided with a secondary fixing strap 202. In other words, a long straight strap and a Y-shaped strap are respectively provided on the left and right sides of the flexible bearing base 10, so as to be suitable for large animals such as rats or rabbits.

[0073] Specifically, when rats or rabbits struggle, their trunks twist with large amplitude and varied directions. A unilateral Y-shaped bifurcated band can specifically strengthen the side with greater stress (such as the side of the back that is prone to arching), while the long straight band on the other side provides basic circumferential fixation, avoiding the operational complexity caused by redundant bilateral structures. Furthermore, the Y-shaped side disperses the tension through the auxiliary band, reducing pressure on the animal's unilateral chest and abdomen (such as avoiding pressure on the sensitive abdominal cavity of rabbits). The long straight side simplifies the fixation process and is suitable for relatively static body areas. Moreover, for large animals, bilateral Y-shaped bands may require multiple adjustments to the length of the auxiliary band, while the combination of a unilateral Y-shaped band and a unilateral straight band reduces the auxiliary band adjustment steps by half, making it particularly suitable for experimental scenarios that require frequent dressing changes.

[0074] Therefore, in actual operation, the experimental objects of different volumes can be selected according to their optimal size, and this case does not impose any restrictions.

[0075] Working principle:

[0076] The flexible support base 10, consisting of an annular rubber frame 100 and a medical polyurethane film 102, conforms to the animal's back. The main fixation strap 20, with its symmetrically arranged Y-shaped bifurcated fixation strap structure, provides rigid constraint to the nylon webbing. The secondary fixation strap 202, made of elastic spandex blended tape, allows for dynamic adjustment around the animal's torso. The tightness can be quickly adjusted using Velcro 200, ensuring stable dressing coverage of the wound. The detachable protective mechanism includes a pre-reserved frame 40 and a magnetic frame 50, with multiple layers of dressing 400 embedded within. The absorbent and water-locking layer 4002 (SAP+fiber cloth) absorbs exudate and maintains wound moisture balance through micro-ventilation channels. The waterproof and stain-resistant layer 4004 (PU film or TPU-coated nonwoven fabric) blocks external contamination. The ventilation holes 300 on the pre-fixation strap 30 further assist in heat dissipation, ultimately achieving an integrated fixation function that is anti-displacement, breathable and absorbent, and quick to replace.

[0077] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A fixation device for a back skin dressing for laboratory animals, comprising a flexible support base (10), characterized in that: The flexible bearing base (10) includes an annular rubber frame (100), and a medical polyurethane film (102) is fixed on the inner periphery of the rubber frame (100); A removable protective structure covering the medical polyurethane film (102); The main fixing straps (20) are symmetrically arranged on the left and right sides of the flexible support base (10), and the slots (10-0) are symmetrically formed on the front end face of the flexible support base (10). The Velcro (200) is provided at the end of the main fixing straps (20), and the secondary fixing straps (202) are provided at the edge of the main fixing straps (20). The other end of the secondary fixing straps (202) is connected to the edge of the flexible support base (10), so that the main fixing straps (20) and the secondary fixing straps (202) form an adjustable Y-shaped bifurcated structure.

2. The fixation device for a back skin dressing for laboratory animals according to claim 1, characterized in that, The main fixing belt (20) and the secondary fixing belt (202) are made of nylon webbing and elastic spandex blended belt, respectively.

3. The fixation device for a back skin dressing for laboratory animals according to claim 1, characterized in that, The protective mechanism includes a reserved frame (40) and a dressing (400) disposed on the front end of the reserved frame (40). The dressing (400) includes an absorbent and water-locking layer (4002) and a waterproof and stain-resistant layer (4004) disposed sequentially from top to bottom.

4. The fixation device for a back skin dressing for laboratory animals according to claim 3, characterized in that, The reserved frame (40) is also connected to a magnetic frame (50).

5. The fixation device for a back skin dressing for laboratory animals according to claim 3, characterized in that, The waterproof and stain-resistant layer (4004) is made of waterproof polyurethane (PU) film or TPU-coated nonwoven fabric.

6. The fixation device for a back skin dressing for laboratory animals according to claim 3, characterized in that, The liquid-absorbing and water-locking layer (4002) is made of SAP (super absorbent polymer) + fiber cloth (viscose fiber).

7. The fixation device for a back skin dressing for laboratory animals according to claim 1, characterized in that, It also includes a fixing mechanism (60), which includes a pair of positioning rings (600) symmetrically arranged on the front of the flexible support base (10), and a flexible fixing band (602) connecting the two positioning rings (600); wherein the flexible fixing band (602) includes a head (6020) and a tail (6022), a plurality of locking holes (604) arranged along the length direction of the flexible fixing band (602), a locking ring (606) slidably sleeved on the flexible fixing band (602), an alloy frame (608) hinged to the tail (6022), and a rotatably arranged buckle (610).

8. The fixation device for a back skin dressing for laboratory animals according to claim 1, characterized in that, The flexible support base (10) is also provided with a pre-fixing band (30) and a plurality of ventilation holes (300) are formed on the pre-fixing band (30).

9. The fixation device for a back skin dressing for laboratory animals according to claim 3, characterized in that, A micro-ventilation channel is also reserved between the liquid-absorbing and water-locking layer (4002) and the waterproof and stain-resistant layer (4004).

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