Auxiliary reduction device for treating atlantoaxial dislocation and use method thereof

Abstract

The present invention discloses a personalized medical device for assisting the reduction of the atlantoaxial joint in clinical treatment of atlantoaxial dislocation, which includes a functional structure, a fixing structure and a personalized module. The functional structure includes a rotating handle, a tightening screw, a mounting plate, a reduction rod, a spherical outer pair, a spherical inner pair and a screw rod, wherein the screw rod and the spherical inner pair are connected by threads; the personalized module is an atlas fitting structure. The matching mode of the reduction rod and the atlas fitting structure is a positioning hole clearance fitting connection, which is suitable for the reduction treatment of anterior dislocation, posterior dislocation and rotational dislocation of the atlantoaxial joint or for the reduction treatment of anterior dislocation of the atlantoaxial joint. The atlas fitting structure can be tightly fitted with the patient's atlas and fixed by winding with steel wire. The spherical pair is used to adjust the direction of the reduction rod, and the tightening screw is used to fix the spherical inner pair after the direction of the reduction rod is adjusted. In the working state, the handle is rotated, and the threaded transmission enables the reduction rod to move forward or backward, and the anterior reduction, posterior reduction and rotational reduction of the atlas are easily achieved.

Description

Technical Field

[0001] The present invention relates to the field of digital medicine and medical devices, and in particular to a design and manufacturing method of a personalized auxiliary reduction medical device for treating atlantoaxial dislocation. Background Art

[0002] Atlantoaxial dislocation, also known as atlantoaxial dislocation, refers to the loss of normal apposition between the first segment (atlas) and the second segment (axis) of the cervical spine. Types of atlantoaxial dislocation include anterior dislocation, posterior dislocation, bilateral asymmetric dislocation and rotational dislocation. Atlantoaxial dislocation can directly or indirectly stimulate and compress the spinal cord, nerves and blood vessels, causing a series of diseases. Typical symptoms include: 1) occipital and neck pain; 2) torticollis and limited neck movement; 3) upper spinal cord damage can manifest as systemic muscle tension, unstable or weak hand grip; weakness in walking; weakness in urination and defecation; limb muscle atrophy; severe cases may cause whole body paralysis; 4) dizziness, tinnitus, blurred vision, chest tightness, palpitations and high blood pressure. Atlantoaxial dislocation may even compress the upper cervical spinal cord due to minor head and neck injuries or excessive flexion and extension of the cervical spine. Patients may suddenly develop spastic paralysis or even respiratory muscle paralysis and die, which requires timely diagnosis and treatment.

[0003] To treat atlantoaxial dislocation, the atlantoaxial must first be repositioned to relieve spinal cord compression, and then the cervical joint must be stabilized to prevent re-dislocation. Atlantoaxial dislocation can be classified into three types: traction reduction, surgical reduction, and irreversible reduction. Surgery at the atlantoaxial site is extremely risky and difficult. In recent years, a series of clinical studies on atlantoaxial dislocation have achieved results, and atlantoaxial fixation treatment technology has also made great progress. Posterior screw fusion combined with digital medicine and 3D printing technology has been perfected. However, atlantoaxial dislocation is still difficult to reposition or even impossible to reposition. In surgical reduction, the traditional method requires the use of a traction device to traction the head to reposition the atlantoaxial, which has certain risks, and the effect is not very ideal, and accurate reduction cannot be achieved. The main problems with traditional atlantoaxial surgical reduction instruments are: (1) Traditional skull traction methods for reducing the atlantoaxial joint are only applicable to cases of atlantoaxial dislocation that can be reduced by traction; (2) Traditional skull traction devices are fixed on the patient's skull and are pulled by heavy objects, which makes them bulky and primitive. This method has a narrow force-bearing area on the skull and excessive local stress, posing a safety hazard; (3) The reduction effect of skull traction methods is not ideal and cannot achieve precise reduction. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a personalized auxiliary reduction device for the treatment of atlantoaxial dislocation, so as to achieve accurate reduction of the patient's atlantoaxial without affecting the subsequent internal fixation of the atlantoaxial.

[0005] The technical solution adopted by the present invention to solve the above technical problems is:

[0006] An auxiliary reduction instrument for treating atlantoaxial dislocation comprises a functional structure, a fixing structure and an atlas fitting structure, wherein the functional structure comprises a handle, a tightening screw, a fixing plate, a reduction rod, a spherical outer pair, a spherical inner pair and a screw rod, wherein the functional structure is arranged on the fixing structure through the fixing plate, the spherical outer pair is fixed to the fixing plate, a rotatable spherical inner pair is arranged inside the spherical outer pair, a plurality of tightening screws are arranged at equal intervals on the spherical outer pair for limiting the spherical inner pair, a screw rod penetrating the center thereof is arranged on the spherical inner pair, a handle is fixed on the top of the screw rod, and a reduction rod is connected to the atlas fitting structure through a positioning hole on the atlas fitting structure, and the atlas fitting structure is a personalized customized structure, the spherical inner pair and the spherical outer pair constitute a spherical pair, the screw rod can freely rotate to adjust the direction of the reduction rod through the spherical pair, so that the reduction rod and the positioning hole of the atlas fitting structure are accurately matched, and after successful matching, the spherical inner pair is fixed by the tightening screw, thereby constituting an auxiliary reduction instrument for treating atlantoaxial dislocation.

[0007] Furthermore, the spherical inner pair is internally provided with a threaded hole passing through its center, and the reset rod is threadedly connected to the threaded hole. The threaded transmission is realized by rotating the screw rod, and then the reset rod is moved up and down, thereby driving the atlas to move or rotate through the atlas fitting structure. The threaded connection can achieve self-locking and fix the current reset state.

[0008] Furthermore, the reduction rod is connected to the atlas fitting structure via a positioning hole provided on the atlas fitting structure, and the reduction rod and the positioning hole are connected with a clearance fit.

[0009] Furthermore, the positioning hole and the reduction rod are connected with a clearance fit, and the positioning hole has no limit on the outward movement of the reduction rod, and is only suitable for reduction treatment of posterior atlantoaxial dislocation.

[0010] Furthermore, a limiting portion is provided on the positioning hole, and a limiting rod is provided at the bottom of the reduction rod. The limiting portion cooperates with the limiting rod to limit the outward movement of the reduction rod, which is suitable for reduction treatment of all atlas dislocation situations. The limiting rod can rotate freely in the positioning hole of the atlas fitting structure.

[0011] Furthermore, the fixing structure includes vacuum suction cups and fixing seats arranged on both sides, the vacuum suction cups are arranged at the bottom of the fixing seats, and the fixing plates are fixedly connected to the tops of the fixing seats arranged on both sides by screws; the fixing structure uses the vacuum suction cups to fix the auxiliary reduction device.

[0012] Alternatively, the fixing structure includes fixing seats arranged on both sides, and fixing protrusions and external fixing blocks arranged on the fixing seats, and the fixing plates are fixedly connected to the tops of the fixing seats arranged on both sides by screws; the fixing structure uses the fixing protrusions, external fixing blocks, bolts and nuts to install the auxiliary reduction instrument on the upper and lower rods at the front end of the operating bed and fix it.

[0013] Furthermore, the atlas fitting structure is a personalized customized structure whose inner surface is completely fitted with the atlas bone surface. The atlas fitting structure can be manufactured using 3D printing technology. The wide contact area makes the bone surface evenly and dispersedly stressed, greatly reducing the risk of damage to the bone due to uneven stress and excessive local stress.

[0014] Furthermore, the position and angle of the atlas fitting structure and its positioning hole can be designed to match the atlantoaxial offset position and deflection angle, and the adjustment direction of the positioning hole in the atlas fitting structure has an angle α with the normal direction of the human coronal plane, 90°≥α≥0°.

[0015] Another object of the present invention is to provide a method for using an auxiliary reduction device for treating atlantoaxial dislocation, comprising the following steps:

[0016] Step A1, collecting medical image data of the affected part of the patient with atlantoaxial dislocation, using medical image data processing software to perform noise reduction, threshold segmentation, three-dimensional reconstruction and other operations on the collected medical image data, reconstructing a three-dimensional model of the patient's head and spine, and restoring the state and position information of the atlantoaxial dislocation;

[0017] Step A2, importing the three-dimensional model reconstructed in step A1 into 3-matic software, and designing a personalized atlas fitting structure that can fit perfectly with the atlas bone surface based on the skull and atlas bone surface;

[0018] Step A3, standardize the design and processing of the functional structure and the fixed structure components, use the selective laser melting technology (SLM), the selective laser sintering technology (SLS) or the fused deposition modeling technology (FDM) to 3D print the atlas fitting structure designed in step A2, and then perform drilling, surface polishing and heat treatment;

[0019] Step A4, disinfecting and sterilizing the instruments processed in step A3 to meet the standards for surgical instruments;

[0020] Step A5: Before the operation, a fixed structure fixing reduction instrument is used to fix the atlas fitting structure so that it fits perfectly with the atlas;

[0021] Step A6: Use the handle to adjust the direction of the reduction rod so that it accurately matches the positioning hole of the atlas fitting structure, tighten the jacking screw, and fix the spherical inner pair;

[0022] Step A7, after all parts of the reduction instrument are fitted and fixed, rotate the handle to drive the atlas to move and rotate. When the handle is rotated, the reduction rod applies force to the fitted part of the atlas in a direction opposite to the direction of atlas dislocation, and the fixation plate plays a force supporting role. After the atlas is reduced, the atlantoaxial fixation surgery is performed.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The use of the atlantoaxial reduction instrument of the present invention does not affect the internal fixation after atlantoaxial reduction, such as pedicle screw placement, etc.;

[0025] (2) The inner surface of the atlas fitting structure of the present invention is completely fitted with the human bone surface, and the wide contact area makes the bone surface evenly and dispersedly stressed, greatly reducing the risk of uneven bone stress and local excessive stress causing damage;

[0026] (3) The personalized reduction device of the present invention can be used in conjunction with a conventional head traction reduction device to solve the “irreducible type” atlantoaxial dislocation classification case;

[0027] (4) After the atlantoaxial joint is repositioned by rotating the handle in the surgical application of the present invention, the threaded connection can be self-locking to fix the current repositioning state, and the atlantoaxial joint fixation can be performed immediately;

[0028] (5) The present invention is not only applicable to any one of the atlantoaxial anterior dislocation and rotational dislocation occurring alone, but also applicable to any two of the atlantoaxial anterior dislocation or posterior dislocation and rotational dislocation occurring simultaneously; when the atlantoaxial dislocation is simultaneously accompanied by rotational dislocation (generally 0 to 60°) and anterior dislocation or posterior dislocation, the atlantoaxial fitting structure and the position and angle of its positioning hole can be designed to match the atlantoaxial offset position and deflection angle;

[0029] (6) The auxiliary reduction device of the present invention does not occupy the peripheral space of the operating table or occupies a very small area, and does not affect the normal surgical operation of the clinician;

[0030] (7) When the handle of the present invention is rotated, the force direction of the atlas fitting structure is opposite to the dislocation direction. In the treatment of posterior atlantoaxial dislocation, the atlantoaxial fitting part and the atlas can be fixed or not fixed;

[0031] (8) The fixed structure and functional structure of the present invention can be designed and manufactured in a standardized or modular manner without the need for 3D printing;

[0032] (9) The resetting rod of the resetting instrument of the present invention can rotate and move freely, and can easily achieve the matching connection with the positioning hole of the atlas fitting part, without the need for a head frame to restore the position of the patient's head and cervical spine during CT scanning. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 : Schematic diagram of the structure of the present invention;

[0034] Figure 2 : A schematic diagram of the structure of the functional structure part of the present invention;

[0035] Figure 3: A schematic structural diagram of the fixed structural part of the present invention;

[0036] Figure 4 : Another structural schematic diagram of the fixed structural part of the present invention;

[0037] Figure 5 : Schematic diagram of the connection structure of the functional structure and the fixed structure;

[0038] Figure 6 : Schematic diagram of the coordination structure between the reduction rod and the atlas fitting structure;

[0039] Figure 7 : Schematic diagram of another matching structure of the reduction rod and the atlas fitting structure;

[0040] Figure 8 : Schematic diagram of angle α.

[0041] In the figure: 1. handle, 2. tightening screw, 3. fixing plate, 4. reduction rod, 5. spherical outer pair, 6. spherical inner pair, 7. screw, 8. atlas fitting structure (personalized module), 9. vacuum suction cup, 10. fixing seat, 11. screw, 12. fixing structure, 13. functional structure, 14. fixing cam, 15. external fixation block. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the embodiments described are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention. It should also be understood that after reading the contents of the present invention, those skilled in the art may make various simple equivalent changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims of the present application.

[0043] The present invention discloses a personalized medical device for assisting the reduction of the atlantoaxial dislocation in clinical treatment, and the device includes a functional structure, a fixing structure and a personalized module. The functional structure includes a rotating handle, a tightening screw, a mounting plate, a reduction rod, a spherical outer pair, a spherical inner pair and a screw, and the screw is connected to the spherical inner pair by a thread; the fixing structure has two types according to the fixing method, the first type is fixed to the ground by a vacuum suction cup (attached Figure 3 ), including a vacuum suction cup and a fixing seat, and the second type uses the operating table rod to fix the personalized reduction instrument to the operating table through bolts and nuts (attached Figure 4 ), including a fixing seat, a fixing convex and an external fixing block; the personalized module includes an atlas fitting part. The matching mode between the reduction rod and the atlas fitting part can be selected according to the reduction direction. Figure 6 or attached Figure 7 Matching method, attached Figure 7 The combination method is suitable for the reduction and treatment of anterior dislocation, posterior dislocation and rotational dislocation of the atlantoaxial spine. Figure 6 The matching method is only applicable to the reduction treatment of anterior atlantoaxial dislocation, and is not applicable to the treatment of all types of dislocation. The atlas fitting structure can fit tightly with the patient's atlas and is fixed by winding a steel wire. The spherical pair is used to adjust the direction of the reduction rod, and the tightening screw is used to fix the spherical inner pair after the direction of the reduction rod is adjusted. When in working state, rotate the handle, and the threaded transmission enables the reduction rod to move forward or backward, easily achieving anterior reduction, posterior reduction and rotational reduction of the atlas. When using the personalized atlantoaxial reduction instrument described in this patent, a traction device can be used to assist.

[0044] Specifically, an auxiliary reduction device for treating atlantoaxial dislocation includes a functional structure 13, a fixing structure 12 and a personalized module structure (atlas fitting structure 8); the atlas fitting structure is a personalized module, which can be used as shown in the attached Figure 6 Type or attachment Figure 7 The atlas fitting structure is a type of structure in which the reduction rod and the positioning hole of the atlas fitting structure are both clearance-fitted, the limiting rod can rotate freely in the positioning hole of the atlas fitting structure, and the atlas fitting structure can be manufactured using 3D printing technology; the atlas fitting structure and the atlas are fixed by means of wire winding and locking.

[0045] like Figure 1 , 2 As shown, the functional structure consists of a handle 1, a tightening screw 2, a fixing plate 3, a reduction rod 4, a spherical outer pair 5, a spherical inner pair 6 and a screw 7; the spherical inner pair 6 and the spherical outer pair 5 form a spherical pair, and its function enables the screw 7 to rotate freely, thereby adjusting the direction of the reduction rod 4 so that the reduction rod 4 can accurately match with the positioning hole of the atlas fitting structure. After successful matching, the tightening screw 2 is tightened to fix the spherical inner pair 6; the spherical inner pair 6 has a threaded hole and cooperates with the screw 7, and the threaded transmission can realize the up and down movement of the reduction rod, thereby driving the atlas to move or rotate.

[0046] As attached Figure 6 This type of positioning hole has no limit on the outward movement of the reduction rod and is only suitable for the reduction treatment of posterior atlantoaxial dislocation; Figure 7 The positioning hole of this type can limit the outward movement of the reduction rod and is suitable for reduction treatment of all atlas dislocation cases.

[0047] The fixing structure may be provided by Figure 3 or attached Figure 4 Two types, with Figure 3 The fixing structure includes a vacuum suction cup 9 and a fixing seat 10. Figure 4 The fixing structure includes a fixing seat 10, a fixing protrusion 14 and an outer fixing block 15; Figure 5 As shown, the fixed structure and the functional structure are connected by screws 11; Figure 3 The type of fixing structure uses a vacuum suction cup to fix the atlantoaxial auxiliary reduction instrument; the attachment Figure 4 The type fixing structure utilizes the fixing protrusion 14, the external fixing block 15, and the bolts and nuts to fix the reduction instrument on the upper and lower rods at the front end of the operating table.

[0048] When the handle 1 is rotated, the direction of force applied by the reduction rod 4 to the atlas fitting structure is opposite to the direction of atlas dislocation, and the fixing plate 3 plays a force supporting role; the inner surface of the atlas fitting structure is completely fitted with the atlas bone surface, and the wide contact area makes the bone surface evenly and dispersedly stressed, greatly reducing the risk of uneven bone stress and damage due to excessive local stress.

[0049] The structural types of the fixed structure and the functional structure can be standardized, but the personalized module structure can be designed and verified according to the atlantoaxial dislocation state and biomechanical analysis, specifically: when the atlantoaxial dislocation is accompanied by rotational dislocation (generally 0-60°) and anterior dislocation, the atlantoaxial fitting structure and the position and angle of its positioning hole can be designed to match the atlantoaxial offset position and deflection angle. The adjustment direction of the positioning hole in the personalized module has an angle α with the normal direction of the human coronal plane; 90≥α≥0°.

[0050] The reduction rod can rotate freely in the positioning hole of the atlas fitting structure; the spherical pair design can realize the free movement of the reduction rod in all directions, and does not require equipment such as a head frame to restore the position state of the head and cervical spine during CT scanning; after the handle is rotated to reduce the atlas, the threaded connection can achieve self-locking, fix the current reduction state, and the atlantoaxial fixation can be performed immediately.

[0051] The method for using the auxiliary reduction device for treating atlantoaxial dislocation comprises the following steps:

[0052] Step A1, collecting medical image data (including but not limited to CT data) of the affected part of the patient with atlantoaxial dislocation, using medical image data processing software (including but not limited to Mimics software) to perform noise reduction, threshold segmentation, three-dimensional reconstruction and other operations on the collected medical image data, reconstructing a three-dimensional model of the patient's head and spine (including at least the atlas and axis), and restoring information such as the state and position of the atlantoaxial dislocation;

[0053] Step A2, importing the three-dimensional model reconstructed in step A1 into 3-matic software, and based on the skull and atlantoaxial bone surfaces, using a series of functions of 3-matic software, designing a personalized atlas fitting structure that can fit perfectly with the atlas bone surface;

[0054] Step A3, using lathe, milling, planing, grinding or CNC machining to process the functional structure and fixed structure components of the standardized design, using selective laser melting (SLM), selective laser sintering (SLS) or fused deposition modeling (FDM) to 3D print the atlas fitting structure designed in step A2, and then perform post-processing such as drilling, surface polishing, and heat treatment;

[0055] Step A4, disinfecting and sterilizing the instruments processed in step A3 to make them meet the relevant use standards of surgical instruments;

[0056] Step A5: Before surgery, use Figure 3 or attached Figure 4 The type of fixed structure fixed reduction device fixes the personalized module so that it fits perfectly with the atlas;

[0057] Step A6: Use the handle to adjust the direction of the reduction rod so that it accurately matches the positioning hole of the atlas fitting structure, and tighten the set screw to fix the spherical inner pair;

[0058] Step A7: After all parts of the reduction instrument are fitted and fixed, rotate the handle to drive the atlas to move and rotate. After the atlas is reduced, perform atlantoaxial fixation.

[0059] The atlantoaxial reduction device used for the treatment of atlantoaxial dislocation has the functions of anterior reduction, posterior reduction and rotational reduction of the atlantoaxial joint. The auxiliary reduction device uses the operating table pole and the ground as force supports, and the patient's cervical spine and skull do not need to be used as force supports; the auxiliary reduction device does not occupy the peripheral space of the operating table or occupies very little space, and does not affect the normal surgical operations of clinicians; the personalized auxiliary reduction device can be used in conjunction with a traditional traction device to assist in reduction.

Claims

1. An auxiliary reduction device for treating atlantoaxial dislocation, Features: The invention comprises a functional structure, a fixing structure and an atlas fitting structure, wherein the functional structure is composed of a handle, a tightening screw, a fixing plate, a reduction rod, a spherical outer pair, a spherical inner pair and a screw rod, wherein the functional structure is arranged on the fixing structure through the fixing plate, the spherical outer pair is fixed on the fixing plate, a rotatable spherical inner pair is arranged inside the spherical outer pair, a plurality of tightening screws are arranged at equal intervals on the spherical outer pair for limiting the spherical inner pair, a screw rod penetrating the center thereof is arranged on the spherical inner pair, a handle is fixed on the top of the screw rod, and a reduction rod is connected to the bottom thereof; the bottom of the reduction rod is arranged on the atlas fitting structure through the fixing plate, and the fixing plate is fixed on ... The positioning hole is connected to the atlas fitting structure, the reduction rod and the positioning hole are connected with a clearance fit, the atlas fitting structure is a personalized customized structure whose inner surface is completely fitted with the atlas bone surface, the atlas fitting structure and the position and angle of the positioning hole are designed to match the atlas-axis offset position and deflection angle, the spherical inner pair and the spherical outer pair form a spherical pair, the screw rod can freely rotate to adjust the direction of the reduction rod through the spherical pair, so that the reduction rod and the atlas fitting structure positioning hole are accurately matched, and after successful matching, the spherical inner pair is fixed by tightening the screw to form an auxiliary reduction instrument; The spherical pair is used to adjust the direction of the reset rod, and the tightening screw is used to fix the spherical inner pair after the direction of the reset rod is adjusted; the spherical inner pair is provided with a threaded hole through its center, and the screw is threadedly connected to the threaded hole. The threaded transmission is realized by rotating the screw, and then the reset rod is moved up and down, thereby driving the atlas to move or rotate through the atlas fitting structure. The threaded connection can achieve self-locking and fix the current reset state.

2. The auxiliary reduction device according to claim 1, Features: The positioning hole does not limit the outward movement of the reset rod.

3. The auxiliary reduction device according to claim 1, Features: A limiting portion is arranged on the positioning hole, and a limiting rod is arranged at the bottom of the reset rod. The limiting portion cooperates with the limiting rod to limit the outward movement of the reset rod, and the limiting rod can rotate freely in the positioning hole of the atlas fitting structure.

4. The auxiliary reduction device according to claim 1, Features: The fixing structure comprises vacuum suction cups and fixing seats arranged on both sides, the vacuum suction cups are arranged at the bottom of the fixing seats, and the fixing plates are fixedly connected to the tops of the fixing seats arranged on both sides by screws.

5. The auxiliary reduction device according to claim 1, Features: The fixing structure comprises fixing seats arranged on both sides, fixing protrusions and external fixing blocks arranged on the fixing seats, and the fixing plates are fixedly connected to the tops of the fixing seats arranged on both sides by screws.

6. The auxiliary reduction device according to claim 1, Features: There is an angle α between the adjustment direction of the positioning hole in the atlas fitting structure and the normal direction of the human body's coronal plane, 90°≥α≥0°.

7. An auxiliary reduction instrument according to any one of claims 1 to 6, wherein the treatment of atlantoaxial dislocation comprises anterior reduction, posterior reduction and rotational reduction of the atlantoaxial dislocation.

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