A scale preset type spherical grinding minimally invasive bone taking device and operation method

Abstract

This invention discloses a pre-set scale spherical grinding minimally invasive bone harvesting device and its operation method, including a channel fixation module, a fixation tube, an outer sheath, an inner drive shaft, a rotation adjustment mechanism, and a drive device. The fixation tube is fixedly connected to the distal end of the channel fixation module. The proximal end of the outer sheath is rotatably mounted on the channel fixation module. The inner drive shaft is rotatably mounted in the distal end of the channel fixation module. The rotation adjustment mechanism is located at the proximal end of the inner drive shaft. A mesh cage is provided at the distal end of the outer sheath. A traction wire is connected between the rotation adjustment mechanism and the mesh cage to pull the mesh cage to expand to the pre-set bone harvesting diameter. The drive device drives the inner drive shaft to rotate the outer sheath, causing the mesh cage to perform spherical grinding of the bone. This invention can pre-determine the bone harvesting diameter through a pre-set scale, accurately control the bone harvesting volume, eliminate the need for repeated adjustments to the grinding range during surgery, and simplify the operation process.

Description

Technical Field

[0001] This invention relates to the technical field of medical devices, and in particular to a scale-preset spherical grinding minimally invasive bone harvesting device and its operation method. Background Technology

[0002] In clinical orthopedic practice, bone grafting is a crucial method for repairing bone defects and promoting bone healing, particularly in trauma orthopedics, spinal surgery, and joint surgery. Traditional bone harvesting methods often involve open surgery, such as cutting bone blocks from the iliac crest. While this yields sufficient bone tissue, it presents challenges including significant trauma, bleeding, postoperative pain, and a high incidence of complications at the donor site (such as hematoma, infection, and sensory abnormalities). With the development of minimally invasive techniques, minimally invasive bone harvesting tools have emerged, designed to harvest bone tissue through smaller incisions, thus reducing surgical trauma. However, currently used minimally invasive bone harvesting tools, such as trephine saws and bone drills (e.g., the trephine cylindrical bone harvester with Chinese utility model patent number CN216221564U), rely heavily on the surgeon's experience and touch to determine the depth and extent of bone harvesting, making it difficult to precisely control the volume of the harvested bone tissue. This not only makes the surgical outcome highly dependent on the surgeon's skill level, leading to significant differences in bone harvesting volume between different surgeons or even between different surgeries performed by the same surgeon, but also makes it impossible to achieve a precise match with the bone harvesting plan (such as the exact volume and shape of the required bone tissue) developed preoperatively based on imaging examinations. If the amount of bone harvested is insufficient, a second bone harvest may be necessary, increasing patient suffering and surgical risks; if the amount of bone harvested is excessive, it may cause unnecessary bone loss in the donor area, and even affect the structural stability and function of the donor area. Summary of the Invention

[0003] The technical problem to be solved by the embodiments of the present invention is to provide a scale-preset spherical grinding minimally invasive bone harvesting device and operation method, which can preset and precisely control the depth and volume of bone harvesting, realize the precise matching of bone harvesting volume with preoperative plan, reduce unnecessary damage to the bone donor area, and reduce surgical risks.

[0004] To achieve the above objectives, this invention discloses a scale-preset spherical grinding minimally invasive bone harvesting device, comprising: Channel fixing module; A fixation tube is fixedly sleeved at the distal end of the channel fixation module, and is anchored to the bone by rotating the fixation tube; An outer tube sheath, the proximal end of which is disposed on the channel fixing module, and a rotary joint is fixedly disposed on the distal end of the outer tube sheath, and a wire mesh is fixedly disposed on the rotary joint; An inner drive shaft is rotatably disposed near the proximal end of the channel fixing module. Drive channels are provided at both ends of the inner drive shaft. The outer sheath is connected to the drive channels of the inner drive shaft. A rotation adjustment mechanism is provided at the proximal end of the inner drive shaft. A traction wire is connected between the rotation adjustment mechanism and the mesh cage. The rotation adjustment mechanism drives the traction wire to move linearly and pull the mesh cage to expand radially to a preset bone harvesting diameter. The drive device has an end cap fixedly installed at the proximal end of the inner drive shaft. The end cap is connected to the drive device so that the drive device drives the inner drive shaft to rotate the mesh cage, so that the mesh cage can perform spherical grinding to extract bone.

[0005] Furthermore, the mesh cage is woven from several shape memory alloy wires, the surface of which is coated with a diamond micron powder grinding layer.

[0006] Furthermore, the rotary joint includes a bushing, a smooth bushing, and a rolling structure. The bushing is fixedly disposed on the distal end of the outer sheath, and the mesh cage is fixedly connected to the bushing. The smooth bushing is slidably disposed within the bushing, and the rolling structure is disposed between the smooth bushing and the bushing. The traction wire is fixedly connected to the smooth bushing and extends to be fixedly connected to the distal end of the mesh cage.

[0007] Furthermore, the rotary joint includes an outer ring, an inner ring, and a needle roller structure. The outer ring is fixedly embedded on the distal end of the outer sheath, and the needle roller structure is evenly arranged between the outer ring and the inner ring. The traction wire is fixedly connected to the inner ring and extends to be fixedly connected to the distal end of the wire mesh cage.

[0008] Furthermore, the two end faces of the channel fixing module are respectively provided with a first channel and a second channel, and a through hole is provided between the first channel and the second channel. The distal end of the inner layer drive shaft is rotatably connected to the second channel of the channel fixing module, and the proximal end of the outer tube sheath is rotatably connected to the first channel of the channel fixing module. The outer tube sheath extends outward through the through hole into the second channel of the channel fixing module and is fixedly connected to the inner layer drive shaft.

[0009] Furthermore, the outer wall of the fixed tube is provided with a guide hole, through which the flushing suction tube extends into the fixed tube to suck out the bone sludge produced by grinding.

[0010] Furthermore, it also includes a core, the proximal end of which is provided with a handle, and the distal end of which is provided with a tip with a semi-self-tapping thread. The core is detachably inserted into the fixation tube, and the tip of the core passes through the distal end of the fixation tube. The outer wall of the distal end of the fixation tube has external threads. By rotating the handle, the fixation tube and the core are screwed into the bone together, and then the core is separated from the fixation tube.

[0011] Furthermore, the rotary adjustment mechanism includes a slider, an adjusting screw, and a handwheel. The handwheel is screwed onto the proximal end of the inner drive shaft, the adjusting screw is fixedly disposed on the distal end of the handwheel, the slider is slidably disposed within the drive channel of the inner drive shaft and threadedly connected to the adjusting screw, and the slider is connected to the proximal end of the traction wire. By rotating the handwheel, the slider moves linearly, thereby driving the traction wire to pull the cage to expand radially. An adjustment cavity for accommodating the handwheel is formed between the end cap and the end of the inner drive shaft, and a first plane and a second plane are provided on both sides of the end cap, the distance between the first plane and the second plane being less than the outer diameter of the handwheel; The end cap is provided with a hexagonal drive hole in the middle so that the output shaft of the drive device can be inserted into the hexagonal drive hole; The handwheel has a circumferential scale corresponding to the predetermined diameter of the wire mesh cage, and an initial pointer is provided on the outer wall of the inner drive shaft.

[0012] The present invention also provides an operating method for a scale-preset spherical grinding minimally invasive bone harvesting device, comprising the following steps: S101. Preoperative planning and reference table: Based on the patient's preoperative imaging data (such as CT), the volume of the bone defect area is measured to determine the required amount of autologous bone graft, and the corresponding target scale value is determined according to the bone harvest volume and the set scale comparison table.

[0013] S102, pre-assembled core: Secure the core tube to the inside of the fixing tube until the semi-self-tapping thread at the tip of the core tube aligns with the external thread of the fixing tube.

[0014] S103. Establish a work channel: With the distal end of the fixation tube perpendicular to the bone surface, the fixation tube and the core are screwed into the bone by rotating the handle until the fixation tube reaches the pre-set depth. Then, the core and the fixation tube are anchored to the bone simultaneously. Finally, the core is removed from the fixation tube, so that a working channel is formed inside the fixation tube.

[0015] S104. Install grinding equipment: The outer sheath and the compressed mesh cage at its distal end are inserted into the interior of the fixation tube and fixedly connected to the proximal end of the fixation tube through the distal end of the channel fixation module, so that the mesh cage reaches the predetermined working position within the cancellous bone.

[0016] S105, Volume Preset: Hold the inner drive shaft and manually adjust the handwheel rotation. Observe the initial pointer on the inner drive shaft. Adjust the setting scale on the handwheel to the target scale found in step S101. Use the slider to drive the traction wire to pull the far end of the net cage, so that the net cage expands radially to the diameter corresponding to the target scale.

[0017] S106. Grinding and removing bone: Hold the channel fixing module and insert the output shaft of the drive device into the hexagonal drive hole of the end cover. The drive device drives the inner drive shaft to rotate the mesh cage, so that the diamond micro-powder grinding layer on the surface of the mesh cage performs spherical grinding on the surrounding bone. The bone is ground into fine bone paste particles and remains in the cavity and mesh of the mesh cage.

[0018] S107, Recycled bone meal: Turn off the drive unit and stop rotating. Insert the flushing and suction tube through the guide hole on the side wall of the fixed tube to flush and suck out the bone mud in the mesh cage and store it for later use.

[0019] S108. Wire cage retraction and reset: Hold the inner drive shaft and rotate the handwheel in the opposite direction to the zero position. The slider will move the traction wire to the far end, releasing the tension on the tail of the cage. Under its own superelastic restoring force, the cage will automatically shrink and return to its initial diameter.

[0020] S109. Withdrawal of equipment: The outer sheath and the retracted mesh cage are pulled out of the fixation tube, and then the core is re-fixed in the fixation tube. The fixation tube is rotated in the opposite direction by the handle to unscrew it from the bone, thus completing the bone harvesting operation.

[0021] Furthermore, in S101, a mathematical model for setting the handwheel scale and the bone volume is pre-established. The mathematical model includes three levels of operational logic: displacement calculation, diameter mapping, and volume conversion. The displacement calculation formula is as follows: ΔL is the telescopic displacement, N is the set scale, P is the single-grid stroke of the handwheel, and K is the total scale of the handwheel. The diameter mapping formula is: , The value represents the real-time diameter at the corresponding scale, and k is the mechanical transmission coefficient. The diameter of the wire mesh cage in its initial contracted state; The volume conversion formula is: V represents the volume of bone harvested; By successively substituting different set scales N into the mathematical model, the corresponding unique bone extraction volume is obtained one by one, and batch calculations are performed to generate a comparison data table in which the set scale and the bone extraction volume correspond one-to-one. The reference data table is made into a scale reference table and pasted on the surface of the inner drive shaft so that the handwheel setting scale can be directly looked up and mapped to the bone volume.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention adopts a spherical mesh cage design, which can adapt to different bone harvesting volume requirements by adjusting the shrinkage diameter of the mesh cage. Furthermore, it uses a flexible spherical mesh cage with a grinding coating on the surface as the working end, and replaces the traditional cutting method with grinding to harvest bone, ensuring low thermal damage during the bone harvesting process, uniform bone paste particles, and avoiding bone cell damage due to the low heat generation of grinding, which is beneficial to maintaining the biological activity of bone cells. (2) The present invention directly converts the correspondence between the handwheel scale and the bone harvesting volume by pre-establishing a mathematical model between the scale and the bone harvesting volume. There is no need for manual calculation during the operation. The current bone harvesting volume can be quickly obtained by simply looking up the table. The operation is simple and intuitive, which can effectively shorten the operation time, reduce the difficulty of the operation, avoid the error caused by manual conversion, improve the accuracy of bone harvesting volume control, and meet the needs of precise control of bone harvesting volume in minimally invasive bone harvesting surgery. Attached Figure Description

[0023] Figure 1 This is a simplified diagram of the overall structure of the present invention; Figure 2 This is a half-sectional view of the overall structure of Example 1; Figure 3 To show Figure 2 A schematic diagram of the structure of part A in the diagram; Figure 4 This is a side view of the overall structure of the present invention. Figure 5 A simplified diagram of the overall structure of the die; Figure 6 This is a half-sectional view of the overall structure of Example 2. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below with reference to the accompanying drawings.

[0025] Example 1: Reference Figure 1 , Figure 2As shown, a scale-preset spherical grinding minimally invasive bone harvesting device includes a channel fixation module 1, a fixation tube 2, an outer sheath 3, an inner drive shaft 4, a rotation adjustment mechanism 5, and a drive device. The distal outer periphery of the channel fixation module 1 has an external thread, and the proximal inner wall of the fixation tube 2 has an internal thread that connects with the external thread, so that the fixation tube 2 is fixedly sleeved on the distal end of the channel fixation module 1. By rotating the fixation tube 2, it is anchored to the bone. The outer sheath 3 is disposed inside the channel fixation module 1. In this embodiment, the outer sheath 3 and the channel fixation module 1 are integrally formed. The two ends of the inner drive shaft 4 are provided with a drive channel 41 that is interconnected. The inner drive shaft 4 is rotatably disposed on the channel fixation module 1 through a bearing. In the distal end of block 1, and the proximal end of the channel fixing module 1, a cover 13 is provided to prevent axial movement of the bearing during operation. The rotation adjustment mechanism 5 is located at the proximal end of the inner drive shaft 4. The distal end of the outer tube sheath 3 is fixedly provided with a rotary joint 62, and a mesh cage 6 is provided on the rotary joint 62. A traction wire 7 is connected between the rotation adjustment mechanism 5 and the mesh cage 6. The rotation adjustment mechanism 5 drives the traction wire 7 to move linearly and pull the mesh cage 6 to expand radially to the preset bone harvesting diameter. The proximal end of the inner drive shaft 4 is fixedly provided with an end cap 10, which is connected to the drive device so that the drive device drives the inner drive shaft 4 to rotate the mesh cage 6, so that the mesh cage 6 can perform spherical grinding to harvest bone.

[0026] In this embodiment, the mesh cage 6 is woven from several shape memory alloy wires. In its natural state, the mesh cage 6 presents a contracted elliptical structure. When the traction wire 7 pulls the distal end of the mesh cage 6 towards the outer sheath 3, the mesh cage 6 will gradually expand and form a spherical structure under traction and compression. The surface of the mesh cage with the spherical structure is used to grind the surrounding bone. The bone is ground into fine particles (bone paste) and stored in the cavity and mesh of the mesh cage 6. Compared with the traditional bone tissue processing method of cutting bone into blocks or strips with a toothed metal cylinder or a ring saw, this embodiment uses grinding instead of the traditional cutting method. This not only obtains bone paste with better shape and uniform particle size, but also significantly reduces surgical thermal damage and bone tissue damage, which is more conducive to maintaining the biological activity of bone cells.

[0027] Furthermore, the surface of the shape memory alloy wire is coated with a diamond micron grinding layer through an electroplating process. The diamond micron particle size is 15-20 micrometers, the thickness of the diamond micron grinding layer is 15-20 micrometers, the hardness of the diamond micron grinding layer is ≥8000HV, and the bonding strength between the diamond micron grinding layer and the nickel-titanium alloy matrix is ​​≥30 MPa. It can withstand repeated expansion and contraction of the mesh cage and high-speed grinding conditions. Compared with the grinding surface of ordinary metal materials, the diamond micron has higher hardness and better grinding sharpness, which can quickly grind bone. At the same time, it will not wear out quickly due to repeated use, effectively extending the service life of the device. Moreover, the diamond micron particles are small and uniform, which can further improve the uniformity of bone paste particles after grinding, reduce the generation of large bone particles, and achieve a firm coating and effective grinding of the diamond micron grinding layer, which is more suitable for the needs of subsequent bone grafting.

[0028] Furthermore, in this embodiment, the rotary joint 62 includes a bushing, a smooth bushing, and a rolling structure. The bushing is fixedly disposed on the distal end of the outer sheath 3, and the mesh cage 6 is fixedly connected to the bushing by welding. The smooth bushing is disposed inside the bushing, and the rolling structure is disposed on the surface of the smooth bushing. Specifically, the rolling structure can be ball bearings evenly distributed along the circumference of the smooth bushing. The traction wire 7 is fixedly connected to the smooth bushing and extends to be fixedly connected to the distal end of the mesh cage 6. When the traction wire 7 moves axially to pull the mesh cage 6 to expand, the smooth bushing can adaptively slide with the movement of the traction wire 7, and can also ensure that the traction wire 7 does not rotate when the outer sheath 3 rotates. This achieves complete decoupling of axial control and rotational motion, avoids the traction wire 7 from torsion and breakage due to synchronous rotation with the outer sheath 3, and also prevents unnecessary fluctuations in traction force during rotation, ensuring the stability of the mesh cage expansion grinding process and better controlling the grinding quality of the bone paste.

[0029] In another embodiment, the rotary joint 62 includes an outer ring, an inner ring, and a needle roller structure. The outer ring is fixedly embedded on the distal end of the outer sheath 3. The needle roller structure is preferably composed of multiple slender cylindrical needle rollers, which are evenly arranged between the outer ring and the inner ring, so that the inner ring can rotate and slide relative to the outer ring. The length direction of the needle rollers is parallel to the axis of the rotary joint 62. In order to maintain the uniform distribution of the needle rollers and the smooth movement, a retainer is provided on the outside of the needle rollers in this embodiment. The traction wire is fixedly connected to the inner ring and extends to be fixedly connected to the distal end of the wire mesh cage.

[0030] When the outer sheath 3 drives the outer ring and the net cage 6 to rotate, the rollers roll between the outer and inner rings, so that the inner ring and the traction wire 7 hardly bear any rotational torque due to rolling friction. This achieves rotational isolation between the traction wire and the net cage 6, preventing the traction wire from twisting or tangling. When the traction wire 7 moves axially, the inner ring transmits the axial thrust to the outer ring through the rollers, thereby driving the far end of the net cage 6 to move axially synchronously, realizing the expansion or contraction of the net cage. Since the rollers are in line contact with the inner and outer rings, the rolling friction is minimal, the axial transmission efficiency is high, and the stability of the traction force during the expansion of the net cage is guaranteed.

[0031] Reference Figure 2 As shown, in this embodiment, the fixation tube 2 is provided with a guide hole 21. After the mesh cage 6 has been ground, the rinsing and suction tube can be inserted into the fixation tube 2 through the guide hole 21 to suck out the bone sludge produced by grinding. At the same time, physiological saline can be injected through the rinsing and suction tube to rinse the surgical area, maintain a clear surgical field, and avoid bone sludge residue affecting the surgical operation or causing postoperative complications. No additional surgical instruments are required, which can effectively reduce surgical steps, shorten the overall operation time, and reduce surgical risks.

[0032] Reference Figure 2 , Figure 3 As shown, the rotary adjustment mechanism 5 includes a slider 51, an adjusting screw 52, ​​and a handwheel 53. The handwheel 53 is screwed onto the proximal end of the inner drive shaft 4. The proximal end of the adjusting screw 52 is provided with a smooth shaft section and is fixedly connected to the handwheel 53. The outer diameter of the smooth shaft section is larger than the outer diameter of the adjusting screw 52, ​​and the proximal end of the smooth shaft section is rotatably connected to the drive channel 41 of the inner drive shaft 4 through a bearing. The drive channel 41 of the inner drive shaft 4 is covered with a sealing cover to confine the adjusting screw and the bearing within the drive channel 41. The slider 51 is slidably disposed within the drive channel 41 of the inner drive shaft 4 and is threadedly connected to the adjusting screw 52. The inner wall of the moving channel 41 has a pair of sliding grooves 42. The slider 51 has protrusions 511 on both sides that slide in conjunction with the sliding grooves 42, so that the slider 51 can only slide along the inner drive shaft 4 axially and will not deflect with the rotation of the adjusting screw 52. The slider 51 is connected to the proximal end of the traction wire 7. In this embodiment, the pitch P of the adjusting screw 52 is 1mm. When the handwheel 53 is rotated, the adjusting screw 52 is driven to move the slider 51 linearly, which in turn drives the traction wire 7 to move synchronously and pull the net cage 6. By controlling the number of rotations of the handwheel 53, the pulling force and traction displacement of the traction wire 7 can be precisely controlled, thereby precisely controlling the expansion diameter of the net cage 6.

[0033] Combination Figure 1As shown, even better, the outer periphery of the handwheel 53 is provided with a set scale corresponding to the predetermined diameter of the mesh cage 6, and the outer wall of the inner drive shaft 4 is provided with an initial pointer. By rotating the handwheel 53, the traction wire 7 is pulled until the preset scale is aligned with the initial pointer. At this time, the expansion diameter of the mesh cage 6 reaches the preset target diameter. There is no need to repeatedly measure and confirm the diameter during the operation. This simplifies the operation process and further improves the dimensional control accuracy of bone grinding, meeting the precise requirements for bone harvesting size in minimally invasive bone harvesting surgery.

[0034] Combination Figure 3 , Figure 4 As shown, further, an adjustment cavity for accommodating the handwheel 53 is formed between the end cap 10 and the end of the inner drive shaft 4, and a first plane 101 and a second plane 102 are provided on both sides of the end cap 10. The distance between the first plane 101 and the second plane 102 is less than the outer diameter of the handwheel 53, so that the outer periphery of the handwheel 53 can be exposed outside the end cap 10, making it convenient for the operator to rotate the handwheel for adjustment.

[0035] The end cap 10 has a hexagonal drive hole 103 in the middle. In this embodiment, the drive device is preferably an orthopedic electric drill. The output shaft of the drive device is inserted into the hexagonal drive hole 103, thereby driving the inner drive shaft 4 to rotate, which in turn drives the expanded mesh cage 6 to grind the bone, thus realizing the electric control of the mesh cage.

[0036] Combination Figure 5 As shown, this embodiment also includes a core 9. The proximal end of the core 9 is provided with a handle 91, and the distal end of the core 9 is provided with a tip 92 with a semi-self-tapping thread. The core 9 is detachably inserted into the fixing tube 2, or the fixing tube and the core can be fitted together using internal and external threads. The tip 92 of the core 9 passes through the distal end of the fixing tube 2, and the outer wall of the distal end of the fixing tube 2 has external threads. The thread of the tip 92 has the same pitch and tooth profile as the external thread of the fixing tube 2. In this embodiment, before grinding and harvesting bone, the fixing tube 2 and the core 9 need to be connected separately. By rotating the handle, the fixing tube 2 and the core 9 are connected together... The core tube 9 is screwed into the bone until the fixation tube 2 reaches the pre-set depth. Then, the core tube 9 and the fixation tube 2 are simultaneously anchored to the bone. The core tube 9 is then separated from the fixation tube 2 and removed, forming a hollow channel inside the fixation tube 2. After the fixation tube 2 is anchored in place and the core tube 9 is removed, it is fixedly connected to the channel fixation module 1. The pre-assembled outer sheath 3 and mesh cage 6 can then be inserted into the hollow channel of the fixation tube 2 to complete the rapid assembly and docking of the surgical device. This ensures that the mesh cage 6 can reach the predetermined working position within the bone without additional positioning adjustments, further shortening the operation time and meeting the operational requirements of minimally invasive surgery.

[0037] Reference Figures 1-5 As shown, the present invention also provides an operating method, comprising the following steps: S101. Preoperative planning and reference table: Based on the patient's preoperative imaging data (such as CT), the volume of the bone defect area is measured to determine the required amount of autologous bone graft, and the corresponding target scale value is determined according to the bone harvest volume and the set scale comparison table.

[0038] S102, pre-assembled core: Secure the core tube to the inside of the fixing tube until the semi-self-tapping thread at the tip of the core tube aligns with the external thread of the fixing tube.

[0039] S103. Establish a work channel: With the distal end of the fixation tube perpendicular to the bone surface, the fixation tube and the core are screwed into the bone by rotating the handle until the fixation tube reaches the pre-set depth. Then, the core and the fixation tube are anchored to the bone simultaneously. Finally, the core is removed from the fixation tube, so that a working channel is formed inside the fixation tube.

[0040] S104. Install grinding equipment: The outer sheath and the compressed mesh cage at its distal end are inserted into the interior of the fixation tube and fixedly connected to the proximal end of the fixation tube through the distal end of the channel fixation module, so that the mesh cage reaches the predetermined working position within the bone.

[0041] S105, Volume Preset: Hold the inner drive shaft and manually adjust the handwheel rotation. Observe the initial pointer on the inner drive shaft. Adjust the setting scale on the handwheel to the target scale found in step S101. Use the slider to drive the traction wire to pull the far end of the net cage, so that the net cage expands radially to the diameter corresponding to the target scale.

[0042] S106. Grinding and removing bone: Hold the channel fixing module and insert the output shaft of the drive device into the hexagonal drive hole of the end cover. The drive device drives the inner drive shaft to rotate the mesh cage, so that the diamond micro-powder grinding layer on the surface of the mesh cage performs spherical grinding on the surrounding bone. The bone is ground into fine bone paste particles and remains in the cavity and mesh of the mesh cage.

[0043] S107, Recycled bone meal: Turn off the drive unit and stop rotating. Insert the flushing and suction tube through the guide hole on the side wall of the fixed tube to flush and suck out the bone mud in the mesh cage and store it for later use.

[0044] S108. Wire cage retraction and reset: Hold the inner drive shaft and rotate the handwheel in the opposite direction to the zero position. The slider will move the traction wire to the far end, releasing the tension on the tail of the cage. Under its own superelastic restoring force, the cage will automatically shrink and return to its initial diameter.

[0045] S109. Withdrawal of equipment: The outer sheath and the retracted mesh cage are pulled out of the fixation tube, and then the core tube is fixed in the fixation tube. The fixation tube is rotated in the opposite direction by the handle to unscrew it from the bone, thus completing the bone harvesting operation.

[0046] Specifically, this device directly determines the bone harvest volume by setting a scale, eliminating the need for repeated measurements and adjustments during the operation. This reduces the operation time and allows for the precise acquisition of the required amount of autologous bone particles, avoiding excessive bone harvesting that could cause additional damage to the donor site. Furthermore, the entire bone harvesting operation can be completed by establishing only one minimally invasive working channel, eliminating the need for open surgery to expose the bone harvesting area. This results in less trauma to the donor site, faster postoperative recovery, and the collected fine bone paste particles are better suited to the filling and transplantation needs of bone defect areas.

[0047] Furthermore, to achieve precise preoperative milliliter-level pre-planning and accurate intraoperative execution of bone harvesting volume, this invention simplifies the traditional complex, experience-based operation into a standardized process of "table lookup, setting, and activation." In S101, a mathematical model for setting the handwheel scale and bone harvesting volume is pre-established. This mathematical model includes three levels of computational logic: displacement calculation, diameter mapping, and volume conversion.

[0048] The displacement calculation formula is as follows: ΔL is the telescopic displacement, N is the set scale, P is the pitch of the adjusting screw, and K is the total scale of the handwheel; The diameter mapping formula is: , The value represents the real-time diameter at the corresponding scale, and k is the mechanical transmission coefficient. The diameter of the wire mesh cage in its initial contracted state; The volume conversion formula is: V represents the volume of bone harvested; By sequentially substituting different set scales N into the mathematical model, the corresponding unique bone extraction volume is obtained one by one. Batch calculations generate a one-to-one correspondence data table between the set scale and the bone extraction volume. The data table is then made into a scale reference table and pasted on the surface of the inner drive shaft so that the bone extraction volume can be directly read from the handwheel set scale.

[0049] In this embodiment, the pitch P of the adjusting screw can be selected as 1.5mm or 2.0mm, the total scale of the handwheel K=50 divisions, the initial diameter of the mesh cage D0=8.0mm, and the transmission coefficient k=6.0.

[0050] Based on the above mathematical model, the cage diameter and bone extraction volume corresponding to different set scales were pre-calculated and a comparison table was prepared (see Table 1 and Table 2): Table 1 (P=1.5mm)

[0051] Maximum bone harvest volume: approximately 2.57 cm³ 3 (Corresponding to scale 50).

[0052] Table 2 (P=2mm)

[0053] Maximum bone harvest volume: approximately 4.19 cm³ 3 (Corresponding to scale 50).

[0054] During the procedure, after the surgeon determines the required bone volume based on the planned amount of bone to be transplanted, they can directly obtain the corresponding target scale by referring to the scale reference table (selected according to the actual product pitch). Simply turning the handwheel to the target scale expands the mesh cage to the predetermined diameter. Then, the drive device is activated to control the mesh cage to perform grinding operations to obtain the preset volume of bone tissue. There is no need for the surgeon to repeatedly estimate and adjust the amount of bone to be harvested during the operation, which reduces the requirement for surgical experience and effectively avoids the problems of insufficient or excessive bone harvesting, thus achieving precise bone harvesting.

[0055] Example 2: Reference Figure 6 As shown, the difference between this embodiment and Embodiment 1 is that the outer sheath 3 and the channel fixing module can also be rotatably connected. The channel fixing module 1 has a first channel at its distal end and a second channel at its proximal end. A through hole is provided between the first channel and the second channel. The distal end of the inner drive shaft 4 is rotatably connected to the second channel of the channel fixing module 1 through a bearing. The proximal end of the outer sheath 3 is rotatably connected to the first channel of the channel fixing module 1 through a bearing. The outer sheath 3 extends outward through the through hole into the second channel of the channel fixing module 1 and is fixedly connected to the drive channel 41 of the inner drive shaft 4. Thus, when the inner drive shaft 4 rotates, it drives the outer sheath 3 to rotate.

[0056] Furthermore, the rotary joint 62 includes a fixed collar, which is fixedly connected to the outer sheath 3. The net cage 6 is fixedly connected to the fixed collar, and the traction wire 7 in the inner drive shaft 4 passes through the fixed collar and is fixedly connected to the net cage 6, so that the net cage rotates under the drive of the outer sheath 3.

[0057] The channel fixing module 1 is fixedly provided with a first cover 11 and a second cover 12 at both the far end and the near end, which are used to confine the bearing inside the first channel and the second channel to prevent axial movement of the bearing during operation, ensure the stable assembly position of each rotating component, and prevent the bone extraction accuracy from being affected by component displacement during bone extraction grinding.

[0058] Of course, the above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They cannot be used to limit the scope of protection of the present invention. All modifications made according to the spirit of the main technical solution of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A scale-preset spherical grinding minimally invasive bone harvesting device, characterized in that, include: Channel fixing module (1); Fixing tube (2), which is fixedly sleeved on the distal end of the channel fixing module (1), and is anchored to the bone by rotating the fixing tube (2); An outer tube sheath (3) is provided with its proximal end on the channel fixing module (1), and a rotary joint (62) is fixedly provided with its distal end. A wire mesh cage (6) is provided on the rotary joint (62). The inner drive shaft (4) is rotatably disposed at the near end of the channel fixing module (1). The two ends of the inner drive shaft (4) are connected to each other by a drive channel (41). The outer sheath (3) is connected to the drive channel (41) of the inner drive shaft (4). A rotation adjustment mechanism (5) is located at the proximal end of the inner drive shaft (4). A traction wire (7) is connected between the rotation adjustment mechanism (5) and the mesh cage (6). The rotation adjustment mechanism (5) drives the traction wire (7) to move linearly and pull the mesh cage (6) to expand radially to the preset bone harvesting diameter. The drive device has an end cap (10) fixedly installed at the proximal end of the inner drive shaft (4). The end cap (10) is connected to the drive device so that the drive device drives the inner drive shaft (4) to rotate the mesh cage (6) so that the mesh cage (6) can perform spherical grinding to extract bone.

2. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The mesh cage (6) is woven from several shape memory alloy wires, and the surface of the shape memory alloy wires is coated with a diamond micro powder grinding layer.

3. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The rotary joint (62) includes a bushing, a smooth bushing, and a rolling structure. The bushing is fixedly disposed on the distal end of the outer sheath (3), and the net cage (6) is fixedly connected to the bushing. The smooth bushing is slidably disposed inside the bushing, and the rolling structure is disposed between the smooth bushing and the bushing. The traction wire (7) is fixedly connected to the smooth bushing and extends to be fixedly connected to the distal end of the net cage (6).

4. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The rotary joint (62) includes an outer ring, an inner ring, and a needle roller structure. The outer ring is fixedly embedded on the distal end of the outer sheath (3). The needle roller structure is evenly arranged between the outer ring and the inner ring. The traction wire (7) is fixedly connected to the inner ring and extends to be fixedly connected to the distal end of the net cage (6).

5. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The two ends of the channel fixing module (1) are respectively provided with a first channel and a second channel. A through hole is provided between the first channel and the second channel. The distal end of the inner layer drive shaft (4) is rotatably connected to the second channel of the channel fixing module (1). The proximal end of the outer tube sheath (3) is rotatably connected to the first channel of the channel fixing module (1). The outer tube sheath (3) extends outward through the through hole into the second channel of the channel fixing module (1) and is fixedly connected to the inner layer drive shaft (4).

6. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The outer wall of the fixed tube (2) is provided with a guide hole (21), and the flushing suction tube extends into the fixed tube (2) through the guide hole (21) to suck out the bone mud generated by grinding.

7. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, It also includes a core (9), the proximal end of which is provided with a handle (91), and the distal end of which is provided with a tip (92) with a semi-self-tapping thread. The core (9) is detachably inserted into the fixation tube (2), and the tip (92) of the core (9) passes through the distal end of the fixation tube (2). The outer wall of the distal end of the fixation tube (2) has external threads. By rotating the handle, the fixation tube (2) together with the core (9) is screwed into the bone, and then the core (9) is separated from the fixation tube (2).

8. The scale-preset spherical grinding minimally invasive bone harvesting device according to claim 1, characterized in that, The rotary adjustment mechanism (5) includes a slider (51), an adjusting screw (52), and a handwheel (53). The handwheel (53) is screwed onto the proximal end of the inner drive shaft (4). The adjusting screw (52) is fixedly disposed on the distal end of the handwheel (53). The slider (51) is slidably disposed in the drive channel (41) of the inner drive shaft (4) and threadedly connected to the adjusting screw (52). The slider (51) is connected to the proximal end of the traction wire (7). By rotating the handwheel (53), the slider (51) moves linearly in conjunction with the traction wire (7), thereby driving the traction wire (7) to pull the net cage (6) to expand radially. An adjustment cavity for accommodating the handwheel (53) is formed between the end cap (10) and the end of the inner drive shaft (4), and a first plane (101) and a second plane (102) are provided on both sides of the end cap (10), the distance between the first plane (101) and the second plane (102) is smaller than the outer diameter of the handwheel (53); The end cap (10) is provided with a hexagonal drive hole (103) in the middle so that the output shaft of the drive device can be inserted into the hexagonal drive hole (103); The handwheel (53) has a set scale along its outer periphery that corresponds to the predetermined diameter of the wire mesh cage (6), and an initial pointer is provided on the outer wall of the inner drive shaft (4).

9. A method of operating the scale-preset spherical grinding minimally invasive bone harvesting device according to any one of claims 1-8, characterized in that, The steps include the following: S101. Based on the patient's preoperative imaging data, measure the volume of the bone defect area, determine the required amount of autologous bone graft, and determine the corresponding target scale value according to the bone harvesting volume and the set scale comparison table. S102. Securely connect the core tube to the inside of the fixed tube until the semi-self-tapping thread at the tip of the core tube is aligned with the external thread of the fixed tube. S103. With the distal end of the fixation tube perpendicular to the bone surface, rotate the handle to drive the fixation tube and the core together into the bone until the fixation tube reaches the pre-set depth. Then, anchor the core and the fixation tube to the bone simultaneously. Finally, remove the core from the fixation tube to form a working channel inside the fixation tube. S104. The outer sheath and the compressed mesh cage at its distal end are inserted into the interior of the fixation tube and fixedly connected to the proximal end of the fixation tube through the distal end of the channel fixation module, so that the mesh cage reaches the predetermined working position in the cancellous bone. S105. Hold the inner drive shaft and manually adjust the handwheel rotation. Observe the initial pointer on the inner drive shaft. Adjust the setting scale on the handwheel to the target scale found in step S101. Drive the traction wire through the slider to pull the far end of the net cage, so that the net cage expands radially to the diameter corresponding to the target scale. S106. Hold the channel fixing module and insert the output shaft of the drive device into the hexagonal drive hole of the end cover. Drive the inner drive shaft through the drive device to rotate the mesh cage at a high speed, so that the diamond micro powder grinding layer on the surface of the mesh cage can perform spherical grinding on the surrounding bone. The bone is ground into fine bone paste particles and remains in the cavity and mesh of the mesh cage. S107. Turn off the drive device and stop the rotation. Insert the flushing suction tube through the guide hole on the side wall of the fixed tube to flush and suck out the bone mud in the mesh cage and store it for later use. S108. Hold the inner drive shaft and rotate the handwheel in the opposite direction to the zero position. The slider will drive the traction wire to move to the far end, releasing the tension on the tail of the cage. The cage will automatically shrink and return to its initial diameter under its own superelastic restoring force. S109. Remove the outer sheath and the retracted mesh cage from the fixation tube, then re-fix the core tube into the fixation tube. Rotate the fixation tube in the opposite direction using the handle to unscrew it from the bone, thus completing the bone harvesting procedure.

10. The operating method according to claim 9, characterized in that, In S101, a mathematical model for setting the handwheel scale and the bone volume is pre-established. The mathematical model includes three levels of operation logic: displacement calculation, diameter mapping, and volume conversion. The displacement calculation formula is as follows: ΔL is the telescopic displacement, N is the set scale, P is the single-grid stroke of the handwheel, and K is the total scale of the handwheel. The diameter mapping formula is: , The value represents the real-time diameter at the corresponding scale, and k is the mechanical transmission coefficient. The diameter of the wire mesh cage in its initial contracted state; The volume conversion formula is: V represents the volume of bone harvested; By successively substituting different set scales N into the mathematical model, the corresponding unique bone extraction volume is obtained one by one, and batch calculations are performed to generate a comparison data table in which the set scale and the bone extraction volume correspond one-to-one. The reference data table is made into a scale reference table and pasted on the surface of the inner drive shaft so that the handwheel setting scale can be directly looked up and mapped to the bone volume.

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