CN115040266A - Knee joint knee bending gap balancer - Google Patents

The invention relates to the technical field of knee joint gap balancing instruments, and discloses a knee joint knee bending gap balancer which comprises a balancing shaft, a tibia plate, a fine tuning assembly and a measuring assembly, wherein a first scale is arranged on the balancing shaft in the vertical direction, the tibia plate is fixed on the tibia plate, the tibia plate is sleeved on the balancing shaft, the balancing shaft and the tibia plate are in vertical sliding fit, and a first locking structure for limiting the relative position between the balancing shaft and the tibia plate is arranged between the balancing shaft and the tibia plate; the fine adjustment assembly is arranged at the upper end of the balance shaft and comprises a fixing frame, a measuring main body, a measuring guide plate and a condyle holding plate, the fixing frame is fixed at the upper end of the balance shaft, and the measuring main body and the condyle holding plate are both fixed on the fixing frame; the knee joint flexion gap balancer provided by the invention solves the problems that the existing knee joint flexion gap balancer cannot complete knee joint flexion gap measurement and cannot simultaneously measure the sizes of femoral condyles.

Knee joint knee bending gap balancer

Technical Field

The invention relates to the technical field of knee joint gap balancing instruments, in particular to a knee joint bending gap balancer.

Background

Knee joint replacement is one of the commonly used operation modes for clinically treating diseases such as knee osteoarthritis, traumatic arthritis, rheumatoid disease and the like at present, and has good postoperative effect. The ultimate goal of osteotomy is to achieve a rectangular flexion and extension gap. To obtain a rectangular gap, currently, the commonly used osteotomy method in clinical practice is a measurement osteotomy (equivalent osteotomy) and a gap balancing method. The equivalent osteotomy technology is relatively popular in China, and mainly carries out positioning through bony anatomical landmarks, and guides the rotation positioning of the femur and the osteotomy of the anterior condyle and the posterior condyle on the principle of how much osteotomy is supplemented. However, in clinical practice, some patients have posterior condylar dysplasia, severe posterior condylar osteophytes, severe posterior condylar wear, and intra-articular deformity, so that the anatomical landmarks of the femur are sometimes difficult to accurately locate. The gap balancing method is to straighten the bone of the gap in advance to obtain a balanced straightened gap, then to use the balanced straightened gap as reference, and to use the same inner and outer side distraction tension to distract the knee-bending gap through the distraction apparatus, and to perform the bone-cutting positioning of the front and rear condyles of the femur, so as to achieve the balance of the inner and outer side gaps and the balance of the flexion and extension gaps in the flexion state. Relative to the measurement osteotomy technique, the gap balancing technique can improve knee joint flexion stability and increase prosthesis service life.

The gap balancer currently used in the market has problems that:

1. only the extension gap can be measured and the size of the femoral condyle cannot be directly measured, and thus the model of the femoral prosthesis cannot be determined.

2. The measurement of the inside and outside clearances is not accurate enough.

3. The knee bending clearance can not be measured, namely the knee bending clearance and the straightening clearance can not be balanced, and the operation effect is greatly reduced.

Therefore, how to measure the knee flexion gap, the size of the femoral condyle and make the measurement more accurate is one of the currently important research topics in the field.

Disclosure of Invention

The present invention is directed to a knee flexion gap balancer, which solves at least one of the above problems of the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

a knee joint flexion gap balancer comprises a balancing shaft, a tibia plate, a fine adjustment assembly and a measurement assembly, wherein first scales are arranged on the balancing shaft in the vertical direction, the tibia plate is fixed on the tibia plate, the tibia plate is sleeved on the balancing shaft, the tibia plate and the balancing shaft are in vertical sliding fit, and a first locking structure used for limiting the relative position of the balancing shaft and the tibia plate is arranged between the balancing shaft and the tibia plate;

the measuring device comprises a balance shaft, a fine adjustment assembly, a measuring main body, a measuring guide plate and a condyle holding plate, wherein the fine adjustment assembly is arranged at the upper end of the balance shaft and comprises a fixing frame, the measuring main body, the measuring guide plate and the condyle holding plate;

the measuring component comprises a scale column and a probe, wherein a second scale is arranged on the scale column in the vertical direction, a vertical sliding space is arranged on the measuring main body, the scale column is in vertical sliding fit with the vertical sliding space, the probe is arranged on the scale column, and the probe is provided with a bending part which bends downwards.

Among this technical scheme, the relative vertical slip between accessible shin bone main part and the balance shaft realizes the adjustment to installing the clearance between fine setting subassembly and the shin bone board of balance shaft upper end, because embrace the condylar board and install on the mount, the side of embracing the condylar board is the L shape roughly, realization that can be fine is to the laminating of thighbone under the state of bending the knee, when the balance shaft drives the fine setting subassembly and removes, has realized embracing the removal of condylar board to finally realized embracing the regulation in clearance between condylar board and the shin bone board. In addition, because be equipped with the first locking structure who is used for injecing the relative position between balanced axle and the shin bone main part, when not influencing the clearance adjustment of bending knee, can lock the clearance state to maintain stable clearance measurement state, be convenient for observe. Because the measuring main body is vertically matched with the measuring guide plate in a sliding manner, the eccentric wheel structure is operated to realize fine adjustment of the relative position change between the measuring guide plate and the measuring main body, and then the fine adjustment position is locked through the second locking structure arranged between the measuring guide plate and the measuring main body, the fine adjustment process comprises the steps that the eccentric wheel structure is operated, the measuring main body moves up and down relative to the measuring guide plate, the condyle holding plate and the measuring main body are both arranged on the balance shaft through the fixing frame, so the movement of the measuring main body can realize the movement of the condyle holding plate, further the fine adjustment of the gap between the condyle holding plate and the tibial plate is realized, meanwhile, the fine adjustment position is locked through the second locking structure, because a scale observation component which is convenient for observing the relative displacement between the measuring main body and the measuring guide plate is arranged between the measuring main body and the measuring guide plate, after the fine adjustment is finished, the specific measured knee bending gap needs to be combined with the scale value on the balance shaft and the scale observation component to display, and finally, determining an accurate knee bending clearance value. The design solves the problem that the existing knee joint gap balancer can only measure the extension gap and can not measure the knee bending gap.

In addition, the size of femoral condyle can not be measured simultaneously by the existing knee joint gap balancer, other auxiliary tools are needed for cooperation measurement, the operation is troublesome, in the design, because the measuring component comprises a scale column and a probe, the probe has a bending part bent downwards and can adapt to the shape of femoral bone, after the knee bending gap is adjusted, the scale column of the measuring component is placed in a vertical sliding space, the end of the bending part of the probe is adjusted to be lapped on the anterior condyle cortical bone, the height of the scale column in the vertical sliding space is determined, the size of the femoral condyle can be determined by directly reading the scale value leaked from the scale column, the model of the femoral prosthesis can be determined conveniently, and more convenience is provided for selecting the femoral prosthesis.

Furthermore, in order to facilitate installation and location of the broach in the operation process, the measuring main body is provided with a broach fixing shaft, the axis of the broach fixing shaft is parallel to the axis of the balance shaft, one side of the broach fixing shaft is provided with an installation hole, and the axis of the installation hole is perpendicular to the axis of the broach fixing shaft.

Further, in order to provide a more convenient and faster probe installation locking mode, the scale column is a hollow cylinder body, the scale column is provided with a probe installation seat, the probe installation seat is provided with a probe installation hole, the axis of the probe installation hole is vertical to the axis of the scale column, one end of the probe penetrating through the probe installation hole is provided with a probe handle, the bending part is positioned at the other end of the probe, the probe installation seat is provided with a probe locking hole, the probe locking hole is internally provided with a probe locking button, the probe locking button comprises a pressing part and a locking part, the locking part is positioned in the probe installation hole and is in vertical sliding fit with the pressing part and the locking part, the locking part is provided with a locking hole, the probe penetrates through the locking hole, the locking hole comprises a large-caliber hole and a small-caliber hole which are communicated with each other, the width of the large-caliber hole is larger than the diameter of the probe, and when the probe is positioned in the small-caliber hole, the hole wall of the small-caliber hole in the width direction is respectively abutted against two sides of the probe.

Furthermore, in order to provide a concrete structure that structural design is simple and can lock the probe, be equipped with the transition arch between small-bore hole and the heavy-calibre hole, the transition arch is located one side in the locking hole and is close to the position of locking hole lower extreme.

Further, in order to provide a concrete structure that structural design is simple and can lock the probe, the small-bore hole includes the spacing face that extends from the bellied tip vertical plane of transition, the one side that is close to spacing face on the probe is equipped with the plane with spacing face butt.

Further, in order to provide a specific device capable of vertically driving the measuring body through rotation of the wrench, so as to facilitate detection of a torque value, and provide more reference for operation control of knee bending clearance adjustment of a worker through data of the torque value, the eccentric wheel structure includes a horizontal strip-shaped hole provided on the measuring body, a rotating operation part provided on the measuring guide plate, and a stopper pin fixed on the rotating operation part, wherein an axis of the stopper pin is deviated from a central axis of the rotating operation part, and the stopper pin is in sliding fit with the horizontal strip-shaped hole.

Furthermore, in order to provide a measuring main body which has a more simplified structure and can be in stable vertical sliding fit with the measuring guide plate, the cross section of the measuring main body is of a T-shaped structure, the measuring main body comprises a middle main body and vertical sliding parts which are symmetrically arranged on two sides of the middle main body, the vertical sliding space is arranged at the vertical sliding part, and the axis of the vertical sliding space is parallel to the extending direction of the vertical sliding part;

the middle main body is provided with a broach fixing shaft mounting cavity, the broach fixing shaft is vertically arranged in the broach fixing shaft mounting cavity, the upper end of the middle main body is provided with a top mounting hole which is convenient for the broach fixing shaft to be placed into the broach fixing shaft mounting cavity from the upper part, the top mounting hole is communicated with the broach fixing shaft mounting cavity, the rear part of the middle main body is provided with an opening which is convenient for mounting a broach, and the opening is communicated with the broach fixing shaft mounting cavity;

in order to conveniently realize the adjustment of the reset state between the measuring guide plate and the measuring main body, the measuring guide plate comprises a sliding groove in vertical sliding fit with the vertical sliding part and a vertical sliding area in vertical sliding fit with the middle main body, two sides of the middle main body are respectively provided with a positioning groove, the measuring guide plate is provided with a bead screw, and when the relative positions of the measuring main body and the measuring guide plate are in the reset state, the end part of the bead screw is positioned in the positioning groove.

Further, in order to provide a concrete design convenient to observe and finely tune scale interval change, the scale observation subassembly is including setting up slider in measuring the main part and the spout of setting on measuring the baffle, spout and the perpendicular sliding fit of slider, be equipped with the third scale on the slider, the centre of third scale is zero scale, and the scale interval upwards increases downwards in proper order, one side of spout is equipped with pointer or the index mark of directional third scale, second locking structure includes locking screw and sets up on measuring the baffle and locking screw thread fit's screw, locking screw stretches into the inboard one end of measuring the baffle and supports tightly with measuring the main part.

Specifically, the scale observation assembly is arranged on the front of the measuring main body and the measuring guide plate, the two sliding blocks are symmetrically arranged, and the two sliding grooves are matched with the two sliding blocks. The locking bolt is located between the two sliding grooves.

Further, in order to conveniently realize the drive to the balance shaft, one side of balance shaft is equipped with the rack, shin bone main part internal rotation is connected with the gear, gear and rack meshing, be equipped with in the shin bone main part and be used for driving gear pivoted knob, be equipped with the perpendicular limit structure of the two perpendicular sliding fit of restriction between shin bone main part and the balance shaft.

The knob is controlled by the wrench to rotate, the knob drives the gear to rotate, the gear drives the balance shaft and the tibia main body to generate vertical relative motion, because the tibial plate is fixed on the tibial main body, the position of the tibial plate is consistent with that of the tibial main body, because the condyle holding plate is arranged at the upper end of the balance shaft extending out of the tibia main body, the adjustment of the gap between the condyle holding plate and the tibia plate is realized along with the process that the balance shaft is equivalent to the tibia main body to vertically move, under the condition that the condyle holding plate and the tibia plate are respectively and tightly abutted against the femur section and the tibia section, namely when the operation knob is controlled by the torque wrench, when the detected torque value reaches a set value, preferably, when the torque value of the torque wrench reaches 5Nm or 50kgf.cm, the gap between the condyle holding plate and the tibia plate is determined, and the specific knee bending gap value can be determined by reading the vertical scale value on the balance shaft. In this design, realize the drive to the balance shaft through the gear, use the gear conduction, reduce frictional resistance, more can improve transmission efficiency.

Further, first locking structure includes rack bar and locking joint portion, the rack bar sets up on the balance shaft, the length direction of rack bar is parallel with the length direction of rack, locking joint portion includes operating portion, rotation portion and joint portion, rotation portion rotates with the shin bone main part and is connected, be equipped with the elastic component between operating portion and the shin bone main part, be equipped with the joint tooth in the joint portion, arbitrary latch joint on joint tooth and the rack bar.

Through the clamping rack that sets up on the vertical direction on the balance shaft and the cooperation of the joint tooth joint on the locking joint portion, at the gear drive in-process, realize the locking to the relative position between balance shaft and the shin bone main part automatically, it is specific, the interval of the latch on the clamping rack is as far as possible less for at the in-process that gear drive balance shaft shifts up for the shin bone main part, can realize the locking effect of more positions on the vertical direction, thereby can more accurate measurement go out the clearance of bending knee. Specifically, when the balance shaft is driven by the gear to move upwards relative to the tibia main body, the locking clamping portion is rotationally connected with the tibia main body, and the locking clamping portion can swing correspondingly under the action of the clamping rack, so that the balance shaft moves upwards more smoothly, and in the process, the elastic piece provides elastic force for the swinging reset of the locking clamping portion; when needs resume initial condition with the balance shaft, then press the operation portion, the elastic component is compressed, locking joint portion counter-clockwise swing for the joint tooth breaks away from the card rack, and reverse drive gear can realize the operation of reseing to the balance shaft.

The invention has the beneficial effects that: among this technical scheme, the relative vertical slip between accessible shin bone main part and the balance shaft realizes the adjustment to installing the clearance between fine setting subassembly and the shin bone board of balance shaft upper end, because embrace the condylar board and install on the mount, the side of embracing the condylar board is the L shape roughly, realization that can be fine is to the laminating of thighbone under the state of bending the knee, when the balance shaft drives the fine setting subassembly and removes, has realized embracing the removal of condylar board to finally realized embracing the regulation in clearance between condylar board and the shin bone board. In addition, because be equipped with the first locking structure who is used for injecing relative position between balanced axle and the shin bone main part, when not influencing the clearance adjustment of bending knee, can lock the clearance state to maintain stable clearance measurement state, be convenient for observe. Because the measuring main body is vertically matched with the measuring guide plate in a sliding manner, the eccentric wheel structure is operated to finely adjust the relative position change between the measuring guide plate and the measuring main body, and then the fine adjustment position is locked through the second locking structure arranged between the measuring guide plate and the measuring main body, the fine adjustment process comprises the steps of operating the eccentric wheel structure, vertically moving the measuring main body relative to the measuring guide plate, and because the condylar embracing plate and the measuring main body are both arranged on the balance shaft through the fixing frame, the movement of the measuring main body can realize the movement of the condylar embracing plate, further the fine adjustment of the gap between the condylar embracing plate and the tibial plate, and simultaneously, the fine adjustment position is locked through the second locking structure, because a scale observation assembly which is convenient for observing the relative displacement between the condylar embracing plate and the measuring guide plate is arranged between the measuring main body and the measuring guide plate, after the fine adjustment is completed, the specifically measured knee bending gap needs to be combined with the scale value on the balance shaft and the scale observation assembly to display, and finally, determining an accurate knee bending clearance value. The design solves the problem that the existing knee joint gap balancer can only measure the extension gap and can not measure the bending gap.

In addition, the size of femoral condyle can not be measured simultaneously by the existing knee joint gap balancer, other auxiliary tools are needed for cooperation measurement, the operation is troublesome, in the design, because the measuring component comprises a scale column and a probe, the probe has a bending part bent downwards and can adapt to the shape of femoral bone, after the knee bending gap is adjusted, the scale column of the measuring component is placed in a vertical sliding space, the end of the bending part of the probe is adjusted to be lapped on the anterior condyle cortical bone, the height of the scale column in the vertical sliding space is determined, the size of the femoral condyle can be determined by directly reading the scale value leaked from the scale column, the model of the femoral prosthesis can be determined conveniently, and more convenience is provided for selecting the femoral prosthesis.

Drawings

FIG. 1 is a schematic perspective view of the present invention;

FIG. 2 is a schematic side view of the present invention;

FIG. 3 is a schematic cross-sectional view taken along line A-A in FIG. 2;

FIG. 4 is a schematic cross-sectional view taken at B-B in FIG. 2;

FIG. 5 is a schematic perspective view of the probe of the present invention;

FIG. 6 is a schematic perspective view of another embodiment of the present invention;

FIG. 7 is a schematic cross-sectional view of the present invention;

FIG. 8 is a schematic view of a first perspective of the present invention with some components separated;

FIG. 9 is a schematic structural view of a second perspective of the present invention with some components separated;

FIG. 10 is a third perspective view of the disassembled state of the components of the present invention;

fig. 11 is a structural diagram of a fourth view angle of the disassembled state of the partial components of the present invention.

Detailed Description

Example 1:

as shown in fig. 1-11, the present embodiment provides a knee flexion gap balancer for knee joint, including a balance shaft 1, a tibia plate 2, a tibia plate 3, a fine adjustment assembly 4 and a measurement assembly 5, wherein a first scale is provided on the balance shaft 1 in a vertical direction, the tibia plate 3 is fixed on the tibia plate 2, the tibia plate 2 is sleeved on the balance shaft 1 and vertically and slidably fits between the balance shaft 1 and the balance shaft 1, in order to conveniently fix the tibia plate 3 on the tibia plate 2, the tibia plate 3 has a connecting portion 3.1 matching with an upper end surface shape of the tibia plate 2, the tibia plate 2 is provided with a positioning pin 2.1 and a first mounting hole 2.2, the connecting portion 3.1 is provided with a positioning hole 3.2 and a second mounting hole 3.3, when mounting, the positioning pin 2.1 is in butt joint with the positioning hole 3.2, and the first mounting hole 2.2 is fixedly connected with the second mounting hole 3.3 through a bolt, so that the tibia plate 3 is fixedly mounted on the tibia plate 2, certainly, the balance shaft 1 penetrates through the tibia main body 2 and also penetrates through a connecting hole 3.4 formed in the connecting part 3.1, and a first locking structure used for limiting the relative position between the balance shaft 1 and the tibia main body 2 is arranged between the balance shaft 1 and the tibia main body 2;

the fine adjustment component 4 is arranged at the upper end of the balance shaft 1, the fine adjustment component 4 comprises a fixing frame 6, a measurement main body 7, a measurement guide plate 8 and a condyle plate 9, the fixing frame 6 is fixed at the upper end of the balance shaft 1, concretely, the balance shaft 1 is a hollow shaft, an insertion shaft of the fixing frame 6 is inserted into the balance shaft 1 and is fixed, the measurement main body 7 and the condyle plate 9 are both fixed on the fixing frame 6 through a fixing shaft 56, the part of the fixing frame 6 extending out of the balance shaft is simultaneously fixedly installed on the measurement main body 7 and the condyle plate 9 through the fixing shaft 56, the condyle plate 9 is positioned above the tibia plate 3, the measurement main body 7 is vertically matched with the measurement guide plate 8 in a sliding manner, a scale observation component convenient for observing relative displacement between the measurement main body 7 and the measurement guide plate 8 is arranged between the measurement main body 7, an eccentric wheel structure used for driving the relative position change between the measurement guide plate 8 and the measurement main body 7 is arranged on the measurement main body 7, and an eccentric wheel structure used for locking the relative position between the measurement guide plate 8 and the measurement main body 7 is arranged A second locking structure;

Example 2:

this embodiment is optimized based on embodiment 1 described above.

Example 3:

this embodiment is optimized based on embodiment 1 described above.

As shown in fig. 2, 4, 5, and 10, in order to provide a more convenient and faster installation and locking manner for the probe 11, the calibration column 10 is a hollow cylinder, the calibration column 10 is provided with a probe installation seat 17, the probe installation seat 17 is provided with a probe installation hole 18, an axis of the probe installation hole 18 is perpendicular to an axis of the calibration column 10, one end of the probe 11, which passes through the probe installation hole 18, is provided with a probe handle 19, the bending portion 14 is located at the other end of the probe 11, the probe installation seat 17 is provided with a probe locking hole 20, the probe locking hole 20 is provided with a probe locking button 21, the probe locking button 21 includes a pressing portion 22 and a locking portion 23, the locking portion 23 is located in the probe installation hole 20 and is in vertical sliding fit with the two, the locking portion 23 is provided with a locking hole 24, the probe 11 passes through the locking hole 24, the locking hole 24 includes a large-diameter hole 25 and a small-diameter hole 26 which are communicated with each other, a width of the large-diameter hole 25 is greater than a diameter of the probe 11, when the probe 11 is located in the small-diameter hole 26, the hole walls of the small-diameter hole 26 in the width direction are respectively abutted against both sides of the probe 11.

Example 4:

Example 5:

Example 6:

this embodiment is optimized based on embodiment 1 described above.

Example 7:

Example 8:

this embodiment is optimized based on embodiment 1 described above.

Example 9:

this embodiment is optimized based on embodiment 1 described above.

Example 10:

this embodiment is optimized based on embodiment 1 described above.

Finally, it should be noted that: the above are merely preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.