CN115040265A

CN115040265A - Knee joint gap balancer

Info

Publication number: CN115040265A
Application number: CN202210615609.4A
Authority: CN
Inventors: 陈思瑶; 贺阳; 王帅; 李金鑫; 祈宇杰
Original assignee: Beijing Chunlizhengda Medical Instruments Co Ltd
Current assignee: Beijing Chunlizhengda Medical Instruments Co Ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-09-13

Abstract

The invention relates to the technical field of knee joint gap balancing instruments, and discloses a knee joint gap balancer which comprises a balancing shaft, a tibia plate and a femoral plate, wherein a rack and first scales are arranged on the balancing shaft along the length direction of the balancing shaft, the tibia plate is fixed on the tibia plate, the tibia plate is sleeved on the balancing shaft and is in vertical sliding fit with the balancing shaft, a first locking structure used for limiting the relative position between the balancing shaft and the tibia plate is arranged between the balancing shaft and the tibia plate, the femoral plate is arranged at the upper end, extending out of the tibia plate, of the balancing shaft, a gear is rotatably connected in the tibia plate, the gear is meshed with the rack, and a knob used for driving the gear to rotate is arranged on the tibia plate; the knee joint gap balancer provided by the invention solves the problem that the measurement precision of the existing knee joint gap balancer on the extension gap is yet to be improved.

Description

Knee joint gap balancer

Technical Field

The invention relates to the technical field of knee joint gap balancing instruments, in particular to a knee joint 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 rectangular gaps, the currently clinically used osteotomy methods are the measurement osteotomy (equivalent osteotomy) and the 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 first straighten the bone of the gap to obtain a balanced straightened gap, then to use the balanced straightened gap as a reference, and to prop open the knee-bending gap by the strutting instrument with the same inner and outer side strutting tension, to carry out 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 under the flexion state. Compared with the measurement osteotomy technology, the gap balancing technology can improve the flexion stability of the knee joint and prolong the service life of the prosthesis.

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, so that 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.

The existing knee joint gap balancer still has the problem that the medial-lateral gap cannot be measured accurately, although the gap balancing method is greatly improved compared with the method for measuring the osteotomy, and the original gap balancer only measures the extension gap, measures the extension gap and the size of the femoral condyle and enables the measurement accuracy to be more accurate, so that the knee joint gap balancer is one of the current important research subjects in the field.

Disclosure of Invention

It is an object of the present invention to provide a knee joint gap balancer to solve at least one of the above problems in the prior art.

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

a knee joint gap balancer comprises a balancing shaft, a shin bone main body, a shin bone plate and a femoral plate, wherein a rack and a first scale are arranged on the balancing shaft along the length direction of the balancing shaft, the shin bone plate is fixed on the shin bone main body, the shin bone main body is sleeved on the balancing shaft and vertically matched with the balancing shaft in a sliding manner, a first locking structure used for limiting the relative position between the balancing shaft and the shin bone main body is arranged between the balancing shaft and the shin bone main body, the femoral plate is arranged at the upper end, extending out of the shin bone main body, of the balancing shaft, a gear is connected in the shin bone main body in a rotating manner, the gear is meshed with the rack, and a knob used for driving the rotation of the gear is arranged on the shin bone main body;

first locking structure includes draw-in gear rack and locking joint portion, the draw-in gear rack sets up on the balance shaft, the length direction of draw-in gear rack 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 draw-in gear rack.

In the technical scheme, the tibia plate and the femur plate are respectively used for being jointed with the cross section of a tibia and the cross section of a femur, when a straightening gap is measured, the femur plate and the tibia plate are firstly inserted between the tibia and the femur from a knee joint, because the balance shaft is provided with the rack, the tibia main body is vertically matched with the balance shaft in a sliding way, the gear in the tibia main body is meshed with the rack, 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 tibia plate is fixed on the tibia main body, the position of the tibia plate is consistent with the position of the tibia main body, because the femur plate is arranged at the upper end of the balance shaft extending out of the tibia main body, in the process that the balance shaft is equivalent to the tibia main body to vertically move, the adjustment of the gap between the femur plate and the tibia plate is realized, under the condition that the femur plate and the tibia plate are respectively tightly abutted against the cross section of the femur and the cross section of the femur, that is, when the knob is controlled by the torque wrench, preferably, when the torque value of the torque wrench reaches 5Nm or 50kgf.cm, the extension gap between the femoral plate and the tibial plate is determined, and the specific extension gap value can be determined by reading the first 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.

In addition, because be equipped with the first locking structure that is used for injecing relative position between balanced axle and the shin bone main part, the joint tooth joint cooperation on the card rack that sets up on the vertical direction on the balanced axle and the joint portion of locking, at the gear drive in-process, the automatic locking that realizes relative position between balanced axle and the shin bone main part, it is concrete, the interval of card tooth is as little as possible on the card rack, make at the in-process that the gear drive balanced axle shifts up relative to the shin bone main part, can realize the locking effect of more points in the vertical direction, thereby can measure out the extension clearance more accurately. 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.

It should be noted that, in order to conveniently realize the installation to locking joint portion, the front of shin bone main part is equipped with the bellying, be equipped with the installation cavity in the bellying, the rotation position is in the installation cavity, the operation position is in the top of bellying, be equipped with the spring between operation portion and the bellying. Need the dynamometry line among the operation process, for the convenient cooperation realization dynamometry line, the front of bellying is equipped with the constant head tank of being convenient for install the operation handle, fixes a position the operation handle in the constant head tank, later fixes a position operation handle and dynamometry line pole, provides convenient for the operation of dynamometry line, and of course, the operation handle also can play the function the same with the handle, provides convenient for the handheld operation in the clearance measurement process.

The femoral plate is detachably arranged at the upper end of the balance shaft extending out of the tibia body, and the fine adjustment assembly is detachably arranged at the upper end of the balance shaft extending out of the tibia body;

the fine adjustment assembly 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, the measuring main body and the condyle holding plate are both fixed on the fixing frame, the condyle holding plate is positioned above the tibia plate, the measuring guide plate and the measuring main body are vertically matched in a sliding manner, a scale observation assembly convenient for observing relative displacement between the measuring main body and the measuring guide plate is arranged between the measuring main body and the measuring guide plate, and the measuring main body is provided with an eccentric wheel structure for driving the relative position between the measuring guide plate and the measuring main body to change and a second locking structure for locking the relative position between the measuring guide plate and the measuring main body;

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.

the fine adjustment assembly 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, the measuring main body and the condyle holding plate are both fixed on the fixing frame, the condyle holding plate is positioned above the tibia plate, the measuring main body and the measuring guide plate are vertically matched in a sliding manner, a scale observation assembly convenient for observing relative displacement between the measuring main body and the measuring guide plate is arranged between the measuring main body and the measuring guide plate, and the measuring main body is provided with an eccentric wheel structure for driving the relative position between the measuring guide plate and the measuring main body to change and a second locking structure for locking the relative position between the measuring guide plate and the measuring main body;

Among this technical scheme, because relative vertical sliding between accessible shin bone main part and the balance shaft, realize the adjustment to the clearance of installing 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 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, can lock the clearance state when not influencing the clearance adjustment of bending the knee 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.

In order to provide a more convenient and faster probe installation locking mode, the scale column is a hollow cylinder body, a probe installation seat is arranged on the scale column, a probe installation hole is arranged on the probe installation seat, 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 arranged at the other end of the probe, a probe locking hole is arranged on the probe installation seat, a probe locking button is arranged in the probe locking hole and comprises a pressing part and a locking part, the locking part is arranged in the probe installation hole and is in vertical sliding fit with the probe installation hole, a locking hole is arranged on the locking part, the probe penetrates through the locking hole, the locking hole comprises a large-caliber hole and a small-caliber hole which are mutually communicated, the width of the large-caliber hole is larger than the diameter of the probe, and when the probe is arranged 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.

In order to provide a concrete structure which has simple structural design and can lock the probe, a transition bulge is arranged between the small-caliber hole and the large-caliber hole, and the transition bulge is positioned at a position, close to the lower end of the locking hole, of one side of the locking hole.

In order to provide a specific structure that structural design is simple and can lock the probe, the small-bore hole includes the spacing face that extends from the protruding tip vertical plane of transition, be equipped with the plane with spacing face butt on the probe near one side of spacing face.

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 specific structure capable of implementing vertical driving of the measuring body through rotation of the wrench, thereby facilitating detection of a torque value, and providing more references for operation control of knee bending clearance adjustment of a worker through data of the torque value, the eccentric wheel structure includes a horizontal bar-shaped hole provided on the measuring body, a rotation operating part provided on the measuring guide plate, and a stopper pin fixed on the rotation operating part, wherein an axis of the stopper pin is offset from a central axis of the rotation operating part, and the stopper pin is in sliding fit with the horizontal bar-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 the installation of 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.

In order to reduce the sliding friction between the measuring main body and the measuring guide plate, the upper end of the vertical sliding part is provided with a cylindrical hole, the lower end of the vertical sliding part is provided with an arc-shaped groove extending downwards from the cylindrical hole, and the outer side of the cylindrical hole forms a sliding block in sliding fit with the sliding 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 limit the vertical sliding relation between the tibia main body and the balance shaft, a vertical limiting structure which limits the vertical sliding fit of the tibia main body and the balance shaft is arranged between the tibia main body and the balance shaft, the vertical limiting structure comprises a sliding groove which is vertically arranged on the balance shaft, and a sliding portion which is vertically in sliding fit with the sliding groove is arranged on the tibia main body. In order to provide a structure more retrencies, and simple to operate swift perpendicular limit structure, the sliding part is the fixed pin of setting in the shin bone main part, the tip and the perpendicular sliding fit of spout that the fixed pin stretched into in the shin bone main part. In order to facilitate the installation of the fixing pin and the tibia main body, the lower end of the sliding groove is designed to be flared, the fixing pin can be fixedly installed on the tibia main body firstly, and then the fixing pin is guided into the sliding groove from the flared design.

Further, for the installation of convenient realization counter gear, it is uncovered to be equipped with the installation that the gear of being convenient for passes through in the shin bone main part, uncovered department of installation is equipped with the baffle. During the installation, can put into the gear installation intracavity that corresponds from the installation is uncovered with the gear, later pass the gear through installation knob on the shin bone main part, again from the uncovered department installation round pin axle of installation, realize the fixed mounting of gear and knob, this kind of design for the shin bone main part can integrated into one piece, and overall structure intensity can obtain guaranteeing, and structural design retrencies, and it is convenient to provide for the swift equipment of subassembly.

In order to guarantee the roughness of shin bone main part external shape and in order to realize the quick assembly disassembly to the baffle, one side of shin bone main part is equipped with the mounting groove, the baffle is located the mounting groove, the baffle passes through the fix with screw in one side of shin bone main part, and is concrete, and the screwhead compresses tightly can realize the stable installation to the baffle on the baffle.

Furthermore, in order to facilitate the handheld operation, a handle is arranged at the lower end of the balance shaft.

Furthermore, in order to visually see whether the straightening clearance is uniform and the soft tissue is loosened at the original position until the straightening clearance is balanced, the femoral plate comprises a deflection part and a graduated scale, a pointer main body is arranged at the upper end of the balance shaft, the deflection part is in running fit with the pointer main body, the running axis between the deflection part and the pointer main body is perpendicular to the axis of the balance shaft, the running axis between the deflection part and the pointer main body is parallel to the symmetrical center line of the femoral plate, the middle position of the graduated scale is provided with zero scales, the scale values are sequentially increased towards two sides, a pointer is arranged on the pointer main body, and the pointer points to the zero scales when the femoral plate is in a horizontal state.

Specifically, because thighbone board and thighbone cross-section laminating, if the uneven then thighbone board of both sides soft tissue can take place corresponding deflection, at this moment, the scale can appear floating to can assist the accurate observation axis of turning up of doctor, through loosening both sides soft tissue, when the pointer is to zero scale on the thighbone board, both inside and outside reach balancedly. It should be noted that, when the soft tissue is loosened, the soft tissue needs to be properly loosened, the soft tissue cannot be loosened in a transition manner, and the gap balance is not absolute inner and outer gap balance nor numerical balance, but the soft tissue balance needs to be satisfied as much as possible under the condition of satisfying the balance.

For more accurate observation scale value, first scale is located rack, rack's interval from the bottom down reduces gradually.

The invention has the beneficial effects that: in the technical scheme, the tibia plate and the femur plate are respectively used for being jointed with a tibia section and a femur section, when a straightening gap is measured, the femur plate and the tibia plate are firstly inserted between a tibia and a femur from a knee joint, because a rack is arranged on a balance shaft, a tibia main body is vertically matched with the balance shaft in a sliding way, a gear in the tibia main body is meshed with the rack, the knob is controlled to rotate through a wrench, a knob drives a gear to rotate, the gear drives the balance shaft and the tibia main body to generate vertical relative motion, because the tibia plate is fixed on the tibia main body, the position of the tibia plate is consistent with that of the tibia main body, because the femur plate is arranged at the upper end of the balance shaft extending out of the tibia main body, in the process that the balance shaft is equivalent to the tibia main body to vertically move, the adjustment of the gap between the femur plate and the tibia plate is realized, under the condition that the femur plate and the tibia plate are respectively abutted against the femur section and the tibia section, that is, when the 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 extension gap between the femoral plate and the tibial plate is determined, and the specific extension gap value can be determined by reading the first 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.

Drawings

FIG. 1 is a schematic view of the present invention for measuring straightened gap;

FIG. 2 is a schematic structural view of a partially disassembled assembly for measuring a straightened gap according to the present invention;

FIG. 3 is a schematic perspective view of the present invention for measuring knee flexion gap;

FIG. 4 is a schematic side view of the present invention for measuring knee flexion gap;

FIG. 5 is a schematic cross-sectional view taken at A-A in FIG. 4;

FIG. 6 is a schematic cross-sectional view taken at B-B in FIG. 4;

FIG. 7 is a schematic perspective view of the probe of the present invention;

FIG. 8 is a perspective view of another angle of view for measuring knee flexion gap according to the present invention;

FIG. 9 is a schematic cross-sectional view of the present invention for measuring knee flexion gap;

FIG. 10 is a schematic view of a partially disassembled component for measuring knee flexion gap according to the present invention from a first perspective;

FIG. 11 is a second perspective view of the partially disassembled components of the present invention for measuring knee flexion gap;

FIG. 12 is a third perspective view of a partially disassembled component for measuring knee flexion gap according to the present invention;

FIG. 13 is a fourth perspective view of a partially disassembled device for measuring knee flexion gap according to the present invention.

In the figure: a balance shaft 1; a tibial main body 2; positioning pins 2.1; a first mounting hole 2.2; a tibial plate 3; a connecting part 3.1; positioning holes 3.2; a second mounting hole 3.3; connecting holes 3.4; a fine adjustment component 4; a measuring assembly 5; a fixed frame 6; a measuring body 7; a middle body 7.1; a vertical sliding part 7.2; a positioning groove 7.3; a measuring guide plate 8; a sliding groove 8.1; a vertical sliding area 8.2; 8.3 of a bead screw; a condyle holding plate 9; a scale post 10; a probe 11; a second scale 12; a vertical sliding space 13; a curved portion 14; a broach fixing shaft 15; a mounting hole 16; a probe mount 17; a probe mounting hole 18; a probe handle 19; a probe locking hole 20; a probe lock button 21; a pressing portion 22; a locking portion 23; a locking hole 24; a large-diameter hole 25; a small-diameter hole 26; a transition projection 27; a stop surface 28; a flat surface 29; a horizontal strip-shaped hole 30; a rotation operation unit 31; a stopper pin 32; a broach fixing shaft mounting cavity 33; a top mounting hole 34; an opening 35; a chute 36; a slider 37; a third scale 38; a locking screw 39; a rack 40; a gear 41; a knob 42; a rack bar 43; an operation section 45; a rotating portion 46; a snap-in portion 47; snap-in teeth 48; a vertical slide groove 49; a fixing pin 50; a handle 51; the boss 52; a mounting cavity 53; a spring 54; a positioning groove 55; a femoral plate 56; an arc-shaped slot 57; a slide block 58; the mounting opening 59; a baffle 60; a screw head 61; a deflecting portion 62; a scale 63; a pointer main body 64; a pointer 65; a fixed shaft 66; nail holes 67.

Detailed Description

Example 1:

as shown in fig. 1-13, the present embodiment provides a knee joint gap balancer, which includes a balance shaft 1, a tibial plate 2, a tibial plate 3 and a femoral plate 56, wherein the balance shaft 1 is provided with a rack 40 and a first scale along its length direction, the tibial plate 3 is fixed on the tibial plate 2, the tibial plate 2 is sleeved on the balance shaft 1 and is in vertical sliding fit with the balance shaft 1, as shown in fig. 10, in order to facilitate fixing the tibial plate 3 on the tibial plate 2, the tibial plate 3 has a connecting portion 3.1 matching with the upper end surface of the tibial plate 2, the tibial 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, the first mounting hole 2.2 is fixedly connected with the second mounting hole 3.3 by a bolt, so as to fixedly mount the tibial plate 3 on the tibial plate 2, certainly, the balance shaft 1 passes through the tibia main body 2 and also passes through a connecting hole 3.4 formed in the connecting portion 3.1, 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 femoral plate 56 is arranged at the upper end of the balance shaft 1 extending out of the tibia main body 2, a gear 41 is rotatably connected in the tibia main body 2, the gear 41 is meshed with the rack 40, and a knob 42 used for driving the gear 41 to rotate is arranged on the tibia main body 2;

as shown in fig. 9, first locking structure includes rack 43 and locking joint portion, rack 43 sets up on balance shaft 1, the length direction of rack 43 is parallel with the length direction of rack 40, locking joint portion includes operating portion 45, rotating portion 46 and joint portion 47, rotating portion 46 rotates with shin bone main part 2 and is connected, be equipped with the elastic component between operating portion 45 and the shin bone main part 2, be equipped with joint tooth 48 on the joint portion 47, joint tooth 48 and the arbitrary latch joint on the rack 43.

In the technical scheme, the tibial plate 3 and the femoral plate 56 are respectively used for being jointed with a tibia section and a femur section, when a straightening gap is measured, the femoral plate 56 and the tibial plate 3 are firstly inserted between the tibia and the femur from a knee joint, because the balance shaft 1 is provided with the rack 40, the tibia main body 2 is vertically matched with the balance shaft 1 in a sliding manner, the gear 41 in the tibia main body 2 is meshed with the rack 40, the knob 42 is controlled to rotate through the wrench, the knob 42 drives the gear 41 to rotate, the gear 41 drives the balance shaft 1 and the tibia main body 2 to generate vertical relative motion, because the tibial plate 3 is fixed on the tibia main body 2, the position of the tibial plate 3 is consistent with the position of the tibia main body 2, because the femoral plate 56 is arranged at the upper end of the balance shaft 1 extending out of the tibia main body 2, in the process of vertically moving along with the balance shaft 1 equivalent to the tibia main body 2, the adjustment of the gap between the femoral plate 56 and the tibial plate 3 is realized, in the case where the femoral plate 56 and the tibial plate 3 are respectively pressed against the femoral section and the tibial section, that is, when the knob 42 is controlled by the torque wrench, the detected torque value reaches a predetermined value, preferably, when the torque value of the torque wrench reaches 5Nm or 50kgf.cm, the extension gap between the femoral plate 56 and the tibial plate 3 is determined, and the specific extension gap value can be determined by reading the first scale value on the balance shaft 1. In this design, realize the drive to balance shaft 1 through gear 41, use gear 41 conduction, reduce frictional resistance, more can improve transmission efficiency.

In addition, because be equipped with the first locking structure that is used for injecing the relative position between balanced axle 1 and the shin bone main part 2, the joint cooperation of the joint tooth 48 on the card rack 43 that sets up and the locking joint portion on the vertical direction on the balanced axle 1, in the transmission process of gear 41, the automatic locking of realizing relative position between balanced axle 1 and the shin bone main part 2, specifically, the interval of the card tooth on the card rack 43 is as little as possible, make in the process of the balanced axle 1 of gear 41 drive for shin bone main part 2 shifts up, can realize the locking effect of more points in the vertical direction, thereby can measure out the extension clearance more accurately. Specifically, when the gear 41 drives the balance shaft 1 to move upward relative to the tibia body 2, due to the fact that the locking clamping portion is rotationally connected with the tibia body 2, the locking clamping portion can swing correspondingly under the action of the clamping rack 43, so that the balance shaft 1 can move upward more smoothly, and in the process, the elastic piece provides elastic force for swinging reset of the locking clamping portion; when the balance shaft 1 needs to be restored to the initial state, the operating portion 45 is pressed, the elastic member is compressed, the locking clamping portion swings counterclockwise, the clamping teeth 48 are separated from the clamping rack 43, and the reverse driving gear 41 can realize the reset operation of the balance shaft 1.

It should be noted that, in order to facilitate the installation of the locking clip portion, a protruding portion 52 is disposed on the front surface of the tibia body 2, an installation cavity 53 is disposed in the protruding portion 52, the rotating portion 46 is located in the installation cavity 53, the operating portion 45 is located above the protruding portion 52, and a spring 54 is disposed between the operating portion 45 and the protruding portion 52. The operation in-process needs the dynamometry line, for the convenience cooperation realizes the dynamometry line, and the front of bellying 52 is equipped with the constant head tank 55 of the installation handle of being convenient for, fixes a position the handle in constant head tank 55, later fixes a position handle and dynamometry line pole, provides convenient for the operation of dynamometry line, and of course, the handle also can play the function the same with handle 51, provides convenient for the handheld operation in the clearance measurement process.

Example 2:

this embodiment is optimized based on embodiment 1 described above.

As shown in fig. 3-13, the instrument further comprises a fine adjustment assembly 4 and a measurement assembly 5, wherein the femoral plate 56 is detachably arranged at the upper end of the balance shaft 1 extending out of the tibia body 2, and the fine adjustment assembly 4 is detachably arranged at the upper end of the balance shaft 1 extending out of the tibia body 2;

the fine adjustment component 4 comprises a fixing frame 6, a measuring main body 7, a measuring guide plate 8 and a condyle holding plate 9, the fixing frame 6 is fixed at the upper end of the balance shaft 1, specifically, the balance shaft 1 is a hollow shaft, an insertion shaft of the fixing frame 6 is inserted into the balance shaft 1 for fixing, the measuring main body 7 and the condyle holding 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 with the measuring main body 7 and the condyle holding plate 9 through the fixing shaft 56, the condyle holding plate 9 is positioned above the tibia plate 3, the measuring guide plate 8 is vertically matched with the measuring main body 7 in a sliding manner, a scale observation component convenient for observing the relative displacement between the measuring main body 7 and the measuring guide plate 8 is arranged between the measuring main body 7 and the measuring guide plate 8, the measuring main body 7 is provided with an eccentric wheel structure for driving the relative position between the measuring guide plate 8 and the measuring main body 7 to change and a second locking structure for locking the relative position between the measuring guide plate 8 and the measuring main body 7;

measuring component 5 includes scale post 10 and probe 11, is equipped with second scale 12 on the vertical direction on the scale post 10, is equipped with vertical sliding space 13 on the measurement main part 7, and scale post 10 and the perpendicular sliding fit in vertical sliding space 13, probe 11 set up on scale post 10, and probe 11 has the flexion 14 of downwarping.

Among this technical scheme, because relative vertical sliding between accessible shin bone main part 2 and the balance shaft 1, the realization is to the adjustment in the clearance of installing between fine setting subassembly 4 and the shin bone board 3 of balance shaft 1 upper end, because embrace condyle board 9 and install on mount 6, the side of embracing condyle board 9 is L shape roughly, the realization that can be fine is to the laminating of thighbone under the state of bending the knee, when balance shaft 1 drives fine setting subassembly 4 and removes, realized embracing condyle board 9's removal, thereby finally realized embracing the regulation in the clearance between condyle board 9 and the shin bone board 3. In addition, because the first locking structure used for limiting the relative position between the balance shaft 1 and the tibia body 2 is arranged between the balance shaft 1 and the tibia body 2, the gap state can be locked while the adjustment of the knee bending gap is not influenced, so that the stable gap measurement state is maintained, and the observation is facilitated. Because the measuring main body 7 is vertically matched with the measuring guide plate 8 in a sliding way, the eccentric wheel structure is operated, the relative position change between the measuring guide plate 8 and the measuring main body 7 can be finely adjusted, then the fine adjustment position is locked through the second locking structure arranged between the measuring guide plate 8 and the measuring main body 7, the fine adjustment process is that the eccentric wheel structure is operated, the measuring main body 7 moves up and down relative to the measuring guide plate 8, because the condyle holding plate 9 and the measuring main body 7 are both arranged on the balance shaft 1 through the fixing frame 6, the movement of the measuring main body 7 can realize the movement of the condyle holding plate 9, further the fine adjustment of the gap between the condyle holding plate 9 and the tibial plate 3 is realized, meanwhile, the fine adjustment position is locked through the second locking structure, and because a scale observation assembly which is convenient for observing the relative displacement between the measuring main body 7 and the measuring guide plate 8 is arranged between the measuring main body 7 and the measuring guide plate 8, after fine adjustment is completed, the specifically measured knee bending clearance needs to be combined with the scale value on the balance shaft 1 and the scale value displayed by the scale observation assembly, and finally, the accurate knee bending clearance value is determined. The problem that the existing knee joint gap balancer can only measure the extension gap and cannot measure the knee bending gap is solved, and meanwhile, the inner and outer gaps can be accurately measured.

In addition, the size of the femoral condyle cannot be measured simultaneously by the existing knee joint gap balancer, other auxiliary tools are needed for matching measurement, and the knee joint gap balancer is troublesome to operate, in the design, because the measuring component 5 comprises the scale column 10 and the probe 11, the probe 11 is provided with the bending part 14 which bends downwards and can adapt to the shape of the femur, after the knee bending gap is adjusted, the scale column 10 of the measuring component 5 is placed in the vertical sliding space 13, the end of the bending part 14 of the adjusting probe 11 is lapped on the anterior condyle cortical bone, the height of the scale column 10 in the vertical sliding space 13 is determined, the size of the femoral condyle can be determined by directly reading the scale value leaked from the scale column 10, so that the model of the femoral condyle can be determined conveniently, and more convenience is provided for selecting the femoral prosthesis.

As shown in fig. 6, 7 and 12, 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 comprises a pressing portion 22 and a locking portion 23, the locking portion 23 is located in the probe installation hole 18 and is vertically matched in a sliding manner, the locking portion 23 is provided with a locking hole 24, the probe 11 passes through the locking hole 24, the locking hole 24 comprises 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 larger 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.

During the installation, install probe locking button 21 in probe mount pad 17 earlier, also be promptly with probe locking button 21 push for big aperture hole 25 and probe mounting hole 18 intercommunication, then probe 11 can pass probe mounting hole 18 and big aperture hole 25, later mention locking button 21, then small aperture hole 26 and probe mounting hole 18 intercommunication and align, and small aperture hole 26 can realize spacing to probe 11, thereby realize the locking to probe 11 mounted position.

In order to provide a specific structure which has a simple structural design and can lock the probe 11, a transition protrusion 27 is arranged between the small-caliber hole 26 and the large-caliber hole 25, and the transition protrusion 27 is positioned at one side of the locking hole 24 and close to the lower end of the locking hole 24.

In order to provide a specific structure which has a simple structural design and can lock probe 11, small-diameter hole 26 includes a limiting surface 28 extending from the end vertical plane of transition projection 27, and a plane 29 abutting against limiting surface 28 is provided on one side of probe 11 close to limiting surface 28.

Example 3:

this embodiment is optimized based on embodiment 2 described above.

As shown in figure 12, in order to facilitate the location of the installed broach during the operation, the measuring body 7 is provided with a broach fixing shaft 15, the axis of the broach fixing shaft 15 is parallel to the axis of the balance shaft 1, one side of the broach fixing shaft 15 is provided with an installation hole 16, and the axis of the installation hole 16 is vertical to the axis of the broach fixing shaft 15.

Example 4:

this embodiment is optimized based on embodiment 2 described above.

As shown in fig. 6, 8 and 10, in order to provide a specific structure capable of driving the measuring body 7 vertically by the rotation of the wrench, thereby facilitating the detection of the torque value, and providing more reference for the operation control of the adjustment of the knee bending clearance of the worker by the data of the torque value, the eccentric wheel structure includes a horizontal bar-shaped hole 30 provided on the measuring body 7, a rotating operation part 31 provided on the measuring guide plate 8, and a stopper pin 32 fixed on the rotating operation part 31, wherein the axis of the stopper pin 32 is deviated from the central axis of the rotating operation part 31, and the stopper pin 32 is slidably fitted with the horizontal bar-shaped hole 30.

Example 5:

this embodiment is optimized based on embodiment 3 described above.

As shown in fig. 10, in order to provide the measuring main body 7 with a more simplified structure and capable of performing stable vertical sliding fit with the measuring guide 8, the cross section of the measuring main body 7 is a T-shaped structure, the measuring main body 7 includes a middle main body 7.1 and vertical sliding portions 7.2 symmetrically arranged at two sides of the middle main body 7.1, a vertical sliding space 13 is arranged at the vertical sliding portion 7.2, and an axis of the vertical sliding space 13 is parallel to an extending direction of the vertical sliding portion 7.2;

as shown in fig. 8 and 12, the middle body 7.1 is provided with a broach fixing shaft mounting cavity 33, the broach fixing shaft 15 is vertically arranged in the broach fixing shaft mounting cavity 33, the upper end of the middle body 7.1 is provided with a top mounting hole 3416 for facilitating the broach fixing shaft 15 to be placed into the broach fixing shaft mounting cavity 33 from above, the top mounting hole 3416 is communicated with the broach fixing shaft mounting cavity 33, the rear of the middle body 7.1 is provided with an opening 35 for facilitating the installation of a broach, and the opening 35 is communicated with the broach fixing shaft mounting cavity 33;

as shown in fig. 10 and 12, in order to facilitate the adjustment of the reset state between the measurement guide plate 8 and the measurement main body 7, the measurement guide plate 8 includes a sliding groove 8.1 vertically slidably engaged with the vertical sliding portion 7.2 and a vertical sliding area 8.2 vertically slidably engaged with the middle main body 7.1, two sides of the middle main body 7.1 are respectively provided with a positioning groove 7.3, the measurement guide plate 8 is provided with a bead screw 8.3, and when the relative position of the measurement main body 7 and the measurement guide plate 8 is in the reset state, the end of the bead screw 8.3 is located in the positioning groove 7.3.

As shown in fig. 10, in order to reduce the sliding friction between the measuring body 7 and the measuring guide 8, the upper end of the vertical sliding part 7.2 is provided with a cylindrical hole, the lower end of the vertical sliding part 7.2 is provided with an arc-shaped slot 57 extending downward from the cylindrical hole, and the outer side of the cylindrical hole is formed with a sliding block 58 which is in sliding fit with the sliding slot 8.1.

Example 6:

this embodiment is optimized based on embodiment 2 described above.

As shown in fig. 3, in order to provide a specific design convenient for observing the change of the fine-adjustment scale value, the scale observation assembly comprises a sliding block 37 arranged on the measurement main body 7 and a sliding groove 36 arranged on the measurement guide plate 8, the sliding groove 36 is vertically matched with the sliding block 37 in a sliding manner, a third scale 38 is arranged on the sliding block 37, the middle of the third scale 38 is a zero scale, the scale values are sequentially increased from top to bottom, an indicator pin or an indicator line pointing to the third scale 38 is arranged on one side of the sliding groove 36, the second locking structure comprises a locking screw 39 and a screw hole arranged on the measurement guide plate 8 and in threaded fit with the locking screw 39, and one end of the locking screw 39 extending into the inner side of the measurement guide plate 8 is abutted against the measurement main body 7.

Specifically, the scale observation assembly is arranged on the front surfaces of the measuring main body 7 and the measuring guide plate 8, the two sliding blocks 37 are symmetrically arranged, and the two sliding grooves 36 are matched with the two sliding blocks 37. The locking bolt is located between the two runners 36.

Example 7:

this embodiment is optimized based on embodiment 1 described above.

As shown in fig. 3 and 5, in order to limit the vertical sliding relationship between the tibia body 2 and the balance shaft 1, a vertical limiting structure is provided between the tibia body 2 and the balance shaft 1 to limit the vertical sliding fit between the tibia body 2 and the balance shaft 1, the vertical limiting structure includes a vertical sliding groove 49 vertically provided on the balance shaft 1, and the tibia body 2 is provided with a sliding portion vertically sliding-fitted with the vertical sliding groove 49. In order to provide a vertical limiting structure with a more simplified structure and convenient and quick installation, the sliding part is a fixing pin 50 arranged on the tibia main body 2, and the end part of the fixing pin 50 extending into the tibia main body 2 is vertically matched with the vertical sliding groove 49 in a sliding manner. In order to facilitate the installation of the fixing pin 50 and the tibial body 2, the lower end of the vertical sliding slot 49 is designed to be flared, the fixing pin 50 may be fixed on the tibial body 2, and then the fixing pin 50 may be guided into the vertical sliding slot 49 through the flared design.

Example 8:

this example was optimized based on example 1 described above.

As shown in fig. 4, in order to facilitate the installation of the gear 41, an installation opening 59 is provided on the tibial main body 2 for the gear 41 to pass through, and a baffle 60 is provided at the installation opening 59. During the installation, can put into corresponding gear 41 installation cavity 53 with gear 41 from the uncovered 59 with the installation, later pass gear 41 through installation knob 42 on shin bone main part 2, again from the uncovered 59 department installation round pin axle of installation, realize the fixed mounting of gear 41 and knob 42, this kind of design for shin bone main part 2 can integrated into one piece, overall structure intensity can obtain guaranteeing, and structural design retrencies, and it is convenient to provide for the swift equipment of subassembly.

In order to guarantee the flatness of the external shape of the tibia main body 2 and achieve the rapid disassembly and assembly of the baffle 60, one side of the tibia main body 2 is provided with a mounting groove, the baffle 60 is located in the mounting groove, the baffle 60 is fixed to one side of the tibia main body 2 through screws, and specifically, the stable installation of the baffle 60 can be achieved by pressing the screw heads 61 on the baffle 60.

Example 9:

this embodiment is optimized based on embodiment 1 described above.

For convenient hand-held operation, the lower end of the balance shaft 1 is provided with a handle 51.

Example 10:

this embodiment is optimized based on embodiment 1 described above.

As shown in fig. 1 and 2, in order to visually see whether the straightening gap is uniform and to release the soft tissue at the original position until the balance is achieved, the femoral plate 56 includes a deflection part 62 and a scale 63, a pointer body 64 is provided at the upper end of the balance shaft 1, the deflection part 62 is rotatably fitted with the pointer body 64, the rotation axis between the deflection part 62 and the pointer body 64 is perpendicular to the axis of the balance shaft 1, the rotation axis between the deflection part 62 and the pointer body 64 is parallel to the symmetrical center line of the femoral plate 56, the middle position of the scale 63 is a zero scale, the scale values are sequentially increased towards both sides, a pointer 65 is provided on the pointer body 64, and the pointer 65 points to the zero scale when the femoral plate 56 is in the horizontal state.

Specifically, because femoral plate 56 and the laminating of thighbone cross-section, if the both sides soft tissue is unbalanced then femoral plate 56 can take place corresponding deflection, at this moment, scale 63 can appear floating to can assist the accurate observation axis of turning up of doctor, through loosening both sides soft tissue, when the pointer pointed zero scale on femoral plate 56, both inside and outside reached the balance. It should be noted that, when the soft tissue is loosened, the soft tissue needs to be properly loosened, the soft tissue cannot be loosened in a transition manner, and the gap balance is not absolute inner and outer gap balance nor numerical balance, but the soft tissue balance needs to be satisfied as much as possible under the condition of satisfying the balance.

For more precise observation of the scale value, the first scale is located at the rack bar 43, and the distance between the rack bars 43 is gradually reduced from bottom to top.

The gap balancing method is more dependent on tools, and the operation steps in the device are as follows:

step 1: knee joint tibia and femur osteotomy

a. The tibia osteotomy is the basis of the whole process, the positioning of the femur and the determination of the external rotation angle are all based on the tibia section, and the tibia osteotomy is generally carried out by adopting a marrow external force line positioning method at present;

b. the femur osteotomy generally adopts an intramedullary positioning method, and the femur valgus angle is preferably 5-7 degrees;

step 2: balancing the straightening gap with a gap test pad and a straightening gap balancer

a. Detecting the straightening gap by using a gap test pad, and detaching the pin if the straightening gap is good; if the straightening gap is loosened, replacing a thicker gap test pad; if the straightening gap is too tight, the balance is achieved through the soft tissue release;

b. after the straightening balance is obtained through the gap test pad, a gap balancer which is used for measuring the straightening gap of the device is inserted.

Firstly, stretching the knee to match the insertion thickness of the gap test pad, and then adjusting the straightening gap by a torque wrench. Note: it is preferable that the torque wrench reaches 5Nm or 50 kgf.cm.

Secondly, by loosening soft tissues on two sides, when the pointer on the femoral plate points to zero scale, the inner side and the outer side are balanced. Note: proper amount of the soft tissue should be loosened, and the soft tissue cannot be loosened excessively.

And step 3: balance of knee bending gap

a. Replacing and installing a fine adjustment component for measuring the knee bending clearance;

b. the knee is tightened by an angle of 90 degrees, so that the value of the torque wrench reaches the value when the straightening clearance is measured;

c. installing a measuring component for measuring the size of the femoral condyle, enabling the end part of the probe 11 to be lapped on the anterior condyle cortical bone by sliding the scale column 10 up and down, reading the scale value on the scale column 10, and determining the type (selecting a small number between two numbers) of the femoral prosthesis: the position of the nail hole 67 can be finely adjusted up and down by operating the rotation operating portion 31 with a 3.5 wrench, and after the adjustment is completed, the relative position between the measurement guide 8 and the measurement body 7 is fixed by tightening the lock screw 39 with a 2.5 wrench.

d. Comparing the position of the nail hole 67 line with the position of the through condyle line, horizontal or internal rotation is preferred, if internal rotation occurs, examination of the tibia osteotomy and the like is recommended.

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.

Claims

1. A knee joint gap balancer, characterized by: the tibia plate is fixed on the tibia main body, the tibia main body is sleeved on the balance shaft and vertically and slidably matched with the balance shaft, a first locking structure used for limiting the relative position between the balance shaft and the tibia main body is arranged between the balance shaft and the tibia main body, the femur plate is arranged at the upper end, extending out of the tibia main body, of the balance shaft, a gear is rotatably connected in the tibia main body and meshed with the gear, and a knob used for driving the gear to rotate is arranged on the tibia main body;

2. A knee joint gap balancer as claimed in claim 1, wherein: the femoral plate is detachably arranged at the upper end of the balance shaft extending out of the tibia body, and the fine adjustment assembly is detachably arranged at the upper end of the balance shaft extending out of the tibia body;

the fine adjustment assembly 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, the measuring main body and the condyle holding plate are fixed on the fixing frame, the condyle holding plate is positioned above the tibia plate, the measuring main body and the measuring guide plate are in vertical sliding fit, a scale observation assembly convenient for observing relative displacement between the measuring main body and the measuring guide plate is arranged between the measuring main body and the measuring guide plate, and the measuring main body is provided with an eccentric wheel structure for driving relative position between the measuring guide plate and the measuring main body to change and a second locking structure for locking the relative position between the measuring guide plate and the measuring main body;

3. A knee joint gap balancer as claimed in claim 2, wherein: the measuring 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 a mounting hole, and the axis of the mounting hole is perpendicular to the axis of the broach fixing shaft.

4. A knee joint gap balancer as claimed in claim 2, wherein: the eccentric wheel structure is including setting up horizontal bar hole in the measurement main part, setting up the rotation operation portion on measuring the baffle, fixes the spacer pin in the rotation operation portion, the central axis of the skew rotation operation portion of axis of spacer pin, spacer pin and horizontal bar hole sliding fit.

5. A knee joint gap balancer as claimed in claim 3, wherein: 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 symmetrically arranged on two sides of the middle main body, the vertical sliding spaces are arranged at the vertical sliding parts, and the axes of the vertical sliding spaces are parallel to the extending direction of the vertical sliding parts;

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;

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 body, two sides of the middle body are respectively provided with a positioning groove, the measuring guide plate is provided with a bead screw, and when the relative position of the measuring main body and the measuring guide plate is in a reset state, the end part of the bead screw is positioned in the positioning groove.

6. A knee joint gap balancer as claimed in claim 2, wherein: the scale observation assembly comprises a sliding block arranged on the measuring main body and a sliding groove arranged on the measuring guide plate, the sliding groove is in vertical sliding fit with the sliding block, third scales are arranged on the sliding block, the middle of the third scales is zero, the scale value is sequentially increased downwards, an indicating needle or an indicating line pointing to the third scales is arranged on one side of the sliding groove, the second locking structure comprises a locking screw rod and a screw hole which is arranged on the measuring guide plate and is in threaded fit with the locking screw rod, and the locking screw rod stretches into one end of the inner side of the measuring guide plate and is tightly abutted to the measuring main body.

7. A knee joint gap balancer as claimed in claim 1, wherein: be equipped with the perpendicular limit structure of the two perpendicular sliding fit of restriction between shin bone main part and the balance shaft, perpendicular limit structure includes the vertical spout that sets up on the balance shaft, be equipped with the sliding part with the perpendicular sliding fit of spout in the shin bone main part.

8. A knee joint gap balancer as claimed in claim 1, wherein: be equipped with the installation that the gear of being convenient for passes through on the shin bone main part uncovered, uncovered department of installation is equipped with the baffle.

9. A knee joint gap balancer as claimed in claim 1, wherein: the lower end of the balance shaft is provided with a handle.

10. A knee joint gap balancer as claimed in claim 1, wherein: the femoral plate comprises a deflection part and a graduated scale, a pointer main body is arranged at the upper end of the balance shaft, the deflection part is in running fit with the pointer main body, the rotating axis between the deflection part and the pointer main body is perpendicular to the axis of the balance shaft, the rotating axis between the deflection part and the pointer main body is parallel to the symmetrical central line of the femoral plate, the middle position of the graduated scale is zero scale, the scale values are sequentially increased towards two sides, a pointer is arranged on the pointer main body, and the pointer points to the zero scale when the femoral plate is in a horizontal state.