Adjustable sternum dilator

Abstract

The invention discloses an adjustable sternum dilator and relates to the field of medical instruments.The adjustable sternum dilator is characterized in that a rack is provided with two fixing arms, at least one fixing arm moves in the X-axis direction, each fixing arm is provided with a plurality of clamping components, and the clamping components move in the Y-axis direction and are used for adjusting the clamping position; the clamping component comprises an upper clamping assembly, the upper clamping assembly comprises an upper clamping plate connected with the fixing arm in a sliding mode, a lower clamping assembly is arranged on the lower side of the upper clamping plate, the lower clamping assembly comprises a lower clamping plate arranged below the upper clamping plate, and the lower clamping plate moves in the Z-axis direction; according to the device, through a multi-stage adjusting mechanism, clamping parameters can be accurately adjusted according to the thicknesses of different parts of the sternum, a good attaching and fixing effect is achieved, bone injuries caused by uneven stress are effectively avoided, and operation safety and operation convenience are improved.

Description

Technical Field

[0001] This invention belongs to the field of medical devices, specifically an adjustable sternal expander. Background Technology

[0002] In cardiac surgery, sternal retractors are key instruments for achieving surgical field exposure after median sternotomy. Currently, the sternal retractors widely used in clinical practice mainly adopt a fixed-size traction hook design. These traction hooks are usually standard shapes such as C-shape and L-shape, and their structural dimensions are determined during manufacturing.

[0003] This fixed-size design has significant drawbacks in practical applications. The human sternum has complex anatomical features along its longitudinal direction, with significant differences in thickness and shape between different parts from the manubrium to the xiphoid process. Fixed-size traction hooks struggle to adapt to these natural anatomical variations, leading to uneven stress distribution at different points during retraction. Particularly in areas where the sternum is thinner, such as near the xiphoid process, standard traction hooks may fail to provide sufficient contact area, resulting in excessive local pressure; conversely, in areas where the sternum is thicker, such as the manubrium, insufficient contact may lead to unstable fixation. Excessive local pressure increases the risk of sternal fractures or cracks, especially in elderly patients with osteoporosis. Furthermore, unstable fixation can cause displacement of the retractor during surgery, affecting the stability of the surgical field. While current techniques attempt to alleviate this problem by providing traction hooks of various sizes, frequent changes during surgery not only prolong surgical time and increase operational complexity but also fail to achieve ideal fit with different parts of the sternum. Summary of the Invention

[0004] The purpose of this invention is to provide an adjustable sternal expander to solve the problems of poor sternal fit, cumbersome operation, and easy bone damage caused by the fixed size of the traction hook in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an adjustable sternal expander, comprising a rack, wherein two fixed arms are provided on the rack, and at least one fixed arm moves along the X-axis direction, and a plurality of clamping members are provided on the fixed arm, and the clamping members move along the Y-axis direction for adjusting the clamping position;

[0006] The clamping component includes an upper clamping assembly, which includes an upper clamping plate slidably connected to the fixed arm. A lower clamping assembly is provided on the lower side of the upper clamping plate. The lower clamping assembly includes a lower clamping plate disposed below the upper clamping plate, and the lower clamping plate moves along the Z-axis direction to adjust the clamping width between the upper clamping plate and the lower clamping plate.

[0007] Preferably, the fixed arm is provided with a guide groove with a recessed groove, and a locking ring is slidably disposed in the recessed groove, and the locking ring moves along the Z-axis to lock the position of the upper plate.

[0008] Preferably, the upper plate is provided with a connecting unit, the connecting unit includes a sleeve disposed on the upper plate, the sleeve is slidably disposed in the guide groove, the sleeve is provided with a guide block, and the guide block is screwed into a locking ring.

[0009] Preferably, a screw is rotatably mounted on the lower clamping plate, the upper end of the screw passes through the upper clamping assembly and is threadedly connected to the upper clamping assembly, and a knob is provided at the upper end of the screw, with a polygonal hole at the top of the knob.

[0010] Preferably, a washer is provided at the lower end of the locking ring to increase friction.

[0011] Preferably, the lower plate is provided with a plurality of guide rods, the upper ends of which pass through the upper plate and are slidably connected to the upper plate, for guiding the movement of the lower plate and increasing its strength.

[0012] Preferably, the inner surfaces of both the lower and upper card plates are provided with reusable medical pads.

[0013] Preferably, the rack is provided with an adjustment component, the adjustment component including a slide seat slidably disposed on the rack, the slide seat being fixedly connected to a corresponding fixed arm, a toothed wheel cooperating with the rack being rotatably disposed on the inner side of the slide seat, the upper end of the toothed wheel passing through the slide seat and connected to a hinge seat, and a handle being hinged to the hinge seat.

[0014] Preferably, the toothed wheel includes a turntable rotatably disposed within a slide, and the turntable is fixedly connected to a hinge seat. Two toothed columns are fixedly disposed on the turntable to form grooves for meshing with the rack.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. By setting an adjustable clamping component, the present invention can precisely adjust the clamping width according to the thickness of different parts of the sternum, so as to achieve a better fit and fixation effect and effectively avoid bone damage caused by uneven force.

[0017] 2. This invention achieves precise lifting and lowering adjustment of the lower clamping plate through the cooperation of screws and knobs. The operation is simple and quick, and the clamping force can be adjusted in real time during the operation.

[0018] 3. This invention achieves the locking and rapid adjustment of the upper plate position on the fixed arm through the sliding cooperation of the locking ring and the guide groove, thereby improving the flexibility and efficiency of surgical operations. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0020] Figure 1 This is a first-view three-dimensional structural diagram provided in Embodiment 1 of the present invention;

[0021] Figure 2 This is a schematic diagram of the second-view three-dimensional structure provided in Embodiment 1 of the present invention;

[0022] Figure 3 This is a three-dimensional structural diagram of the adjustment component and its associated parts provided in Embodiment 1 of the present invention;

[0023] Figure 4 A first-view perspective three-dimensional structural diagram of the clamping member and its associated components provided in an embodiment of the present invention;

[0024] Figure 5 A second-view perspective three-dimensional structural diagram of the clamping member and its associated components provided in an embodiment of the present invention;

[0025] Figure 6 A three-dimensional structural diagram of the toothed spur wheel and its associated components provided in an embodiment of the present invention;

[0026] Figure 7 This is a three-dimensional structural schematic diagram provided for Embodiment 2 of the present invention.

[0027] In the picture:

[0028] 1. Rack; 2. Fixed arm; 3. Upper clamping assembly; 301. Upper clamping plate; 302. Locking ring; 303. Connecting unit; 3031. Guide block; 3032. Sleeve; 4. Lower clamping assembly; 401. Lower clamping plate; 402. Screw; 403. Guide rod; 5. Adjusting assembly; 501. Handle; 502. Hinge seat; 503. Slide seat; 504. Gear wheel; 5041. Gear column; 5042. Turntable; 6. Guide groove; 7. Knob; 8. Washer. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] As attached Figure 1 To be continued Figure 7 As shown:

[0031] Example 1: This invention provides an adjustable sternal expander, comprising a rack 1 made of high-strength stainless steel with a polished surface to enhance durability and cleanliness. Two fixing arms 2 are provided on the rack 1. One fixing arm 2 is fixedly connected to the left end of the rack 1, and the other fixing arm 2 is movably mounted on the rack 1 via an adjusting assembly 5. This fixing arm 2 moves along the X-axis to accommodate different sternal widths in different patients. Two clamping components are provided on the fixing arm 2, which move along the Y-axis to adjust the clamping position for alignment with different parts of the sternum. The clamping components include an upper clamping assembly 3, which includes an upper clamping plate 301 slidably connected to the fixing arm 2. The upper clamping plate 301 is made of medical-grade titanium alloy, possessing high strength and biocompatibility. A lower clamping assembly 4 is provided on the lower side of the upper clamping plate 301. The lower clamping assembly 4 includes a lower clamping plate 401 located below the upper clamping plate 301. The lower clamping plate 401 moves along the Z-axis direction through a screw 402 mechanism to precisely adjust the clamping width between the upper clamping plate 301 and the lower clamping plate 401, thereby adapting to the thickness changes of different parts of the sternum.

[0032] During the procedure, the operator first adjusts the movable fixing arm 2 using the adjusting component 5, based on the width of the patient's sternum, to adapt the distance between the two fixing arms 2 to the sternum size. Then, the operator slides the clamping component along the Y-axis, aligning the upper clamping plate 301 and the lower clamping plate 401 with the target area of ​​the sternum. Finally, by rotating the knob 7, the operator moves the lower clamping plate 401 along the Z-axis, adjusting the clamping width to ensure a tight fit against the sternum. This multi-level adjustment mechanism allows for precise adjustment of clamping parameters according to the thickness of different parts of the sternum, achieving excellent fit and fixation, effectively avoiding bone damage caused by uneven force, and improving surgical safety and ease of operation.

[0033] As attached Figure 1 To be continued Figure 3 As shown, in one embodiment of the present invention, the fixed arm 2 is provided with a guide groove 6 with a countersunk groove. The countersunk groove is precision machined, and a locking ring 302 is slidably disposed in the countersunk groove. The locking ring 302 moves along the Z-axis to lock the position of the upper clamping plate 301. The locking ring 302 adopts an internal thread design and cooperates with the connecting unit 303 to achieve quick locking.

[0034] During operation, the operator first loosens the locking ring 302, slides the upper clamping plate 301 along the guide groove 6 to the target position, and then tightens the locking ring 302 to press the fixed arm 2. Through the cooperation of the locking ring 302 and the groove, the upper clamping plate 301 is securely locked on the fixed arm 2 to prevent displacement during the operation and ensure the accuracy of the clamping position.

[0035] As attached Figure 4 To be continued Figure 5As shown, in one embodiment of the present invention, a connecting unit 303 is provided on the upper clamping plate 301. The connecting unit 303 includes a sleeve 3032 disposed on the upper clamping plate 301, and the sleeve 3032 is slidably disposed in the guide groove 6. A guide block 3031 is provided on the sleeve 3032, and the guide block 3031 is screwed into connection with the locking ring 302. The outer surface of the guide block 3031 is provided with an external thread, which matches the internal thread of the locking ring 302.

[0036] During operation, the operator first rotates the locking ring 302, causing the guide block 3031 to move up and down within the locking ring 302, thereby driving the sleeve 3032 to slide within the guide groove 6. When the locking ring 302 is tightened, the threaded engagement between the guide block 3031 and the locking ring 302 generates pressure, fixing the sleeve 3032 within the guide groove 6. This connection method enables fine-tuning and reliable locking of the upper clamping plate 301, enhancing operational flexibility and stability.

[0037] As attached Figure 4 To be continued Figure 5 As shown, in one embodiment of the present invention, a screw 402 is rotatably mounted on the lower clamping plate 401. The screw 402 adopts a fine thread design to achieve precise micro-adjustment. The upper end of the screw 402 passes through the upper clamping assembly 3 and is threadedly connected to the upper clamping assembly 3. A knob 7 is provided at the upper end of the screw 402. The surface of the knob 7 is provided with anti-slip texture to facilitate operation by doctors wearing gloves. The top of the knob 7 is provided with a polygonal hole, such as a hexagonal hole, which can be used with an Allen wrench to tighten or loosen the knob, thereby improving the stability of the fixation.

[0038] During operation, the operator first rotates knob 7 to rotate screw 402. Since screw 402 is threadedly connected to upper clamping assembly 3, lower clamping plate 401 moves along the Z-axis to adjust the distance between it and upper clamping plate 301. Through the fine thread design of screw 402, the clamping width can be precisely controlled to ensure uniform pressure on the sternum and reduce the risk of bone damage.

[0039] As attached Figure 4 To be continued Figure 5 As shown, in one embodiment of the present invention, a gasket 8 is provided at the lower end of the locking ring 302. The gasket 8 is made of rubber material to increase friction. The gasket 8 is fixed to the lower end of the locking ring 302 by bonding or pressing.

[0040] During operation, when the operator first tightens the locking ring 302, the gasket 8 contacts the surface of the fixed arm 2, and the elastic deformation of the rubber material increases the friction of the contact surface. The setting of the gasket 8 enhances the locking effect of the locking ring 302, prevents the upper plate 301 from accidentally sliding during the operation, and improves the reliability of the equipment.

[0041] As attached Figure 4 To be continued Figure 5As shown, in one embodiment of the present invention, two guide rods 403 are provided on the lower clamping plate 401. The upper end of the guide rod 403 passes through the upper clamping plate 301 and is slidably connected to the upper clamping plate 301, serving to guide the movement of the lower clamping plate 401 and increase its strength. The guide rod 403 is made of high-strength stainless steel, and a lubricating coating is provided at the sliding connection with the upper clamping plate 301 to reduce friction.

[0042] During operation, when the operator first adjusts the height of the lower clamping plate 401, the guide rod 403 slides along the guide hole of the upper clamping plate 301 to ensure that the lower clamping plate 401 moves smoothly and avoids tilting; through the supporting effect of the guide rod 403, the overall structural strength of the clamping component is enhanced, and it can withstand the large load during the opening process.

[0043] In one embodiment of the present invention, both the lower card plate 401 and the upper card plate 301 are provided with reusable medical pads on their inner surfaces. The pads are made of medical-grade silicone material and are fixed to the inner surfaces by snaps or adhesives, possessing elasticity and biocompatibility.

[0044] During operation, when the staff holds the sternum, the soft pad comes into direct contact with the surface of the sternum and adapts to the shape of the sternum through elastic deformation. The soft pad protects the sternal tissue from damage by hard objects, while increasing friction to prevent slippage and improve the safety of the operation.

[0045] As attached Figure 3 and attached Figure 6 As shown, in one embodiment of the present invention, an adjustment component 5 is provided on the rack 1. The adjustment component 5 includes a slide block 503 slidably disposed on the rack 1. The slide block 503 is fixedly connected to a corresponding fixed arm 2. A toothed wheel 504 cooperating with the rack 1 is rotatably disposed on the inner side of the slide block 503. The upper end of the toothed wheel 504 passes through the slide block 503 and is connected to a hinge seat 502. A handle 501 is hinged to the hinge seat 502. The meshing mechanism between the toothed wheel 504 and the rack 1 refers to the ratchet mechanism in the prior art to achieve one-way locking.

[0046] During operation, the operator first moves handle 501 to the horizontal position to disengage the gear sprocket 504 from the rack 1, and then moves the fixed arm 2 to the target position; then, the operator moves handle 501 back to the vertical position, and the gear sprocket 504 engages and locks with the rack 1. By adjusting component 5, the fixed arm 2 can be quickly positioned and securely locked on the rack 1, simplifying the surgical procedure.

[0047] As attached Figure 6As shown, in one embodiment of the present invention, the toothed wheel 504 includes a turntable 5042 rotatably disposed within a slide 503, and the turntable 5042 is fixedly connected to a hinge seat 502. Two toothed pillars 5041 are fixedly disposed on the turntable 5042 to form grooves for meshing with the rack 1. The toothed pillars 5041 are made of hardened steel and have high wear resistance. During operation, when the handle 501 is in the vertical position, the two toothed pillars 5041 mesh with the tooth grooves of the rack 1 to form a groove structure, preventing the slide 503 from moving; when the handle 501 is turned, the turntable 5042 rotates, and the toothed pillars 5041 disengage from the rack 1. The double-point meshing design of the toothed pillars 5041 enhances the reliability and stability of the locking and prevents loosening during the opening process.

[0048] Working principle: At the start of the surgery, the doctor first adjusts the relative positions of the two fixation arms 2 according to the width of the patient's sternum: The handle 501 of the adjustment component 5 is moved to the horizontal position, disengaging the gear wheel 504 from the rack 1. After moving the movable fixation arm 2 to the appropriate position, the handle 501 is returned to the vertical position to lock it in place. Then, the clamping components are adjusted according to the thickness of different parts of the sternum: the locking ring 302 is loosened, and the upper clamping plate 301 is moved along the guide groove 6 to the target position before tightening the locking ring 302 to lock it in place. Finally, the screw 402 is driven by rotating the knob 7, causing the lower clamping plate 401 to move along the guide rod 403, adjusting the clamping width so that the upper and lower clamping plates fit tightly against the sternum, with the soft pad protecting the bone tissue. Throughout the process, a multi-stage adjustment mechanism achieves precise clamping, avoiding uneven force distribution.

[0049] Example 2: As shown in the attached document Figure 7 As shown, this embodiment is basically the same as Embodiment 1, except that both fixation arms 2 are movably mounted on the rack 1 via adjustment components 5. This design allows the surgeon to independently adjust the position of the two fixation arms 2, providing a greater range of adjustment and flexibility. It is particularly suitable for patients with special body types or complex surgical situations, enabling asymmetric or special angle expansion. During operation, the surgeon can adjust the position of the two fixation arms 2 on the rack 1 separately to find the optimal expansion point. The clamping components on each fixation arm 2 can still be independently adjusted in terms of clamping position and clamping width, achieving multi-dimensional and multi-parameter precise control. This design is particularly suitable for surgical situations requiring asymmetric or special angle expansion.

[0050] Working principle: Similar to Embodiment 1, but with the addition of independent adjustment function for the position of the fixation arm 2. The doctor can operate the two handles 501 separately to adjust the position of the two fixation arms 2; other operating steps are the same as in Embodiment 1. This design provides greater operational flexibility and adaptability while retaining all the advantages of Embodiment 1.

[0051] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An adjustable sternal expander, characterized in that: Includes a rack (1), on which two fixed arms (2) are provided, and at least one fixed arm (2) moves along the X-axis direction. The fixed arm (2) is provided with a plurality of clamping members, and the clamping members move along the Y-axis direction to adjust the clamping position. The clamping component includes an upper clamping assembly (3), which includes an upper clamping plate (301) slidably connected to the fixed arm (2). A lower clamping assembly (4) is provided on the lower side of the upper clamping plate (301). The lower clamping assembly (4) includes a lower clamping plate (401) disposed below the upper clamping plate (301), and the lower clamping plate (401) moves along the Z-axis direction to adjust the clamping width between the upper clamping plate (301) and the lower clamping plate (401).

2. The adjustable sternal expander according to claim 1, characterized in that: The fixed arm (2) is provided with a guide groove (6) with a sink groove. A locking ring (302) is slidably provided in the sink groove, and the locking ring (302) moves along the Z-axis to lock the position of the upper plate (301).

3. An adjustable sternal expander according to claim 2, characterized in that: The upper plate (301) is provided with a connecting unit (303), the connecting unit (303) includes a sleeve (3032) provided on the upper plate (301), and the sleeve (3032) is slidably disposed in the guide groove (6). The sleeve (3032) is provided with a guide block (3031), and the guide block (3031) is screwed into the locking ring (302).

4. An adjustable sternal expander according to claim 3, characterized in that: A screw (402) is rotatably mounted on the lower plate (401). The upper end of the screw (402) passes through the upper plate assembly (3) and is threadedly connected to the upper plate assembly (3). A knob (7) is mounted on the upper end of the screw (402). A polygonal hole is mounted on the top of the knob (7).

5. An adjustable sternal expander according to claim 4, characterized in that: The lower end of the locking ring (302) is provided with a gasket (8) to increase friction.

6. An adjustable sternal expander according to claim 5, characterized in that: The lower plate (401) is provided with a number of guide rods (403). The upper end of the guide rod (403) passes through the upper plate (301) and is slidably connected to the upper plate (301) for guiding the movement of the lower plate (401) and increasing its strength.

7. An adjustable sternal expander according to claim 1, characterized in that: The inner sides of both the lower card plate (401) and the upper card plate (301) are provided with reusable medical pads.

8. An adjustable sternal expander according to claim 1, characterized in that: An adjustment component (5) is provided on the rack (1). The adjustment component (5) includes a slide (503) slidably disposed on the rack (1). The slide (503) is fixedly connected to the corresponding fixed arm (2). A toothed wheel (504) is rotatably disposed on the inner side of the slide (503) and used in conjunction with the rack (1). The upper end of the toothed wheel (504) passes through the slide (503) and is connected to a hinge seat (502). A handle (501) is hinged on the hinge seat (502).

9. An adjustable sternal expander according to claim 8, characterized in that: The gear wheel (504) includes a turntable (5042) rotatably disposed in a slide (503), and the turntable (5042) is fixedly connected to the hinge seat (502). Two gears (5041) are fixedly disposed on the turntable (5042) to form a groove for meshing with the rack (1).

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