Patent Publication Number: US-2021169507-A1

Title: Detector for artificial joint replacement

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application is a divisional of U.S. application Ser. No. 15/818,342, filed Nov. 20, 2017, which claims priority to Korean Patent Application No. 10-2017-0107078, filed Aug. 24, 2017, the entire contents of which are incorporated herein for all purposes by this reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates generally to a smart surgical instrument for artificial joint replacement. More particularly, the present invention relates to a smart surgical instrument for artificial joint replacement, the smart surgical instrument including a femur resection device for resecting a femur, a tibia resection device for resecting a tibia, and a detector having a shape corresponding to the resected surfaces of the femur and the tibia, in which: the femur resection device includes a laser device which eliminates the need of drilling an intramedullary hole for alignment of the femur during femur resection, thereby preventing complications; the tibia resection device includes a laser device which eliminates the need of using an extramedullary aligner for tibia resection, thereby enabling an easy and fast surgical operation; and the detector includes a rotation detection means and a pressure detection means disposed between trials, thereby enabling numerical verification for balance of forces and a rotation state of components, which enables a precise, accurate, easy, and fast surgical operation. 
     Description of the Related Art 
     The knee joint is an articulation that joins a tibia and a femur. When the knee joint cannot properly function for reasons such as being worn or damaged, it is replaced with an implant (i.e. artificial joint) through a knee replacement surgery known as knee arthroplasty. 
     Knee arthroplasty is a complex surgical procedure requiring a highly precise and skilled surgical technique. An implant used in the knee arthroplasty is mainly composed of a tibial component, a femoral component, and an insert being interposed between the tibial component and the femoral component and functioning like a bearing. 
     To implant the tibial component and the femoral component, a proximal end of a tibia and a distal end of a femur need to be resected by predetermined amounts. Since stability and mobility of the artificial knee joint depend on the inclination angles of the resected surfaces and the resection amounts of the femur and tibia, resecting the end portions of the femur and tibia needs to be highly precisely performed. Accordingly, alignment parts (cutting guide portions) need to be used to guide resection surfaces of the tibia and the femur. 
     The invention disclosed in Patent document discloses a guide assembly for guiding a cutting device that cuts away a distal end of a femur and a proximal end of a tibia during a knee arthroplasty. This technology uses a method of drilling deep holes in the femur and the tibia and inserting intramedullary rods (IM rods) into the holes for alignment of the femur and the tibia. 
     However, drilling deep holes for insertion of the IM rods as in the conventional technology may cause various complications. For example, bone cells in the holes are damaged or may be infected by bacteria, or a fat embolism in which fatty matter flows into a vein to block the flow of blood may occur due to damage of bone marrow. In addition, the drilling also requires strong force and increases the number of tools for a surgical operation, which complicates the surgical procedure and lengthens the operation time with which a surgeon is burdened. 
     As illustrated in  FIG. 1 , according to the conventional technology, a hole H is drilled in a femur  91  using a drill D so that an intramedullary rod (IM rod) can be inserted into the hole H.  FIG. 2  illustrates a surgical instrument with a large knob A used to insert the intramedullary rod into the hole H. The axial alignment technique involving the drilling is disadvantageous in terms of complicated operation processes and low space utilization efficiency due to the fact that a number of surgical instruments having a large size are used. 
     As to resection of a tibia, as illustrated in  FIG. 3 , an extramedullary alignment member J extending from a proximal end  931  to a distal end  933  of a tibia is used for axial alignment of the tibia. The alignment member J has a larger volume than the tibia  93 . Therefore, a surgical operation using the alignment member J is complicated and takes a long time. The complicated procedure and lengthened operation time negatively affect a patient&#39;s health and burden surgeons. 
     With reference to  FIG. 4 , after the distal end  913  of the femur and the proximal end  931  of the tibia are resected, whether the femur and the tibia are properly resected is verified with a balance checker  5 ′. Alternatively, after trials having the same shape as implants (prostheses) are attached to the resected surfaces, the respected surfaces are verified with the balance checker  5 ′. The tibia  93  is flexed or extended with respect to the femur  91  and a gap between the femur  91  and the tibia  93  is checked. As a result, the distal end  913  of the femur  91  or the proximal end  931  of the tibia  93  is further resected or the implants are replaced with new ones having a different size in accordance with the verification results. 
     The balance checker  5 ′ used in the conventional technology has a problem of providing imprecise verification results because such a verification is only visually performed by eye. Therefore, the accuracy of verification results largely relies on experience and sensation of a surgeon. With reference to  FIG. 4 , an alignment member J′ is attached to one side of the balance checker  5 ′ for alignment of the balance checker  5 ′. Since the alignment member J′ has a large volume and an installation time thereof is long, it is likely to burden a surgeon and to negatively affect a patient&#39;s health. 
     Therefore, surgical instruments for artificial joint replacement, which can easily and rapidly align cutting guide portions and have reduced sizes, are needed to enable an effective surgical operation during replacement of an artificial joint. Furthermore, the surgical instruments need to be equipped with a function of precisely and easily verifying medial and lateral force balance after resection of bones. 
     DOCUMENT OF RELATED ART 
     Patent Document 
     Korean Patent No. 10-1612332 (registered as of Apr. 7, 2016) “Guide Assembly For Guiding Cuts To A Femur And Tibia During A Knee Arthroplasty” 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an objective of the present invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument being beneficial to a patient&#39;s health and being capable of reducing a surgeon&#39;s burden by easily and rapidly aligning components of the surgical instrument by using a laser device. 
     Another objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument being capable of preventing bone cells from being damaged or infected with bacteria and preventing complications such as a fat embolism by eliminating a process of drilling an intramedullary hole in a femur by aligning a femur resection device using a laser device. 
     A further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument being equipped with no additional device having a large volume because it aligns a femur resection device for resecting a femur using a laser device, thereby simplifying and speeding up a surgical operation process, which alleviates a burden to both a surgeon and a patient. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument being equipped with two laser devices for alignment of a femur, thereby enabling easy and quick verification for alignment of a femur resection device both on a coronal plane and a sagittal plane during alignment of a femur, which alleviates a burden to a surgeon and enables a precise and accurate alignment. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument being equipped with a rotation detection means in a femur resection device, thereby enabling numerical verification for a rotation state of a fixing portion, which alleviates a burden to a surgeon and enables an easy operation and a precise and accurate alignment. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument aligning a tibia resection device for resection of a tibia using a laser beam, thereby improving space utilization efficiency and reducing a burden to a surgeon and a patient by not using an additional extramedullary aligner for alignment of the tibia. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument including a tibia resection device equipped with a rotation detection means, thereby enabling precise numerical verification for an alignment state of a tibia cutting guide portion during alignment of the tibia cutting guide portion, which reduces a mental burden to a surgeon and enables an easy operation and a precise and accurate alignment. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument including a detector having a shape corresponding to that of the resected surface of a tibia, in which the detector includes a rotation detection means, thereby providing precise numerical verification for a rotation state of an implant during alignment of the implant, which reduces a mental burden to a surgeon and enables an easy operation and a precise and accurate alignment. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument including a detector equipped with a pressure detection means, thereby enabling precise numerical verification for medial and lateral balance and pressure distribution of an implant, which reduces a burden to a surgeon and enables an easy operation and a precise and accurate alignment. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument including a detector having a knob means so that the detector can be easily installed and removed by holding the knob means. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument including a balance checker mounted with a detector, in which the balance checker includes a laser device which enables verification for axial alignment with a laser beam during balance checking, which enables a fast and easy operation. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument charging a battery of a detector in an wireless manner, thereby enabling an easy, simple, and fast operation. 
     A yet further objective of the invention is to provide a smart surgical instrument for an artificial joint replacement, the instrument having a structure in which a battery and a detector are detachably combined with each other so that the battery can be conveniently charged. 
     In order to accomplish the above object, the present invention is implemented by embodiments having the structures described below. 
     According to one embodiment of the present invention, there is provided a smart surgical instrument for an artificial joint replacement, the surgical instrument including a laser device, thereby easily and conveniently performing alignment of components thereof by using the laser device. 
     According to another embodiment of the present invention, the surgical instrument may further include a femur resection device for resecting a femur, wherein the femur resection device includes a laser device, thereby eliminating a process of drilling an intramedullary hole for alignment of the femur during resection of the femur, thereby preventing complications attributable to drilling the intramedullary hole. 
     According to a further embodiment of the present invention, the femur resection device may include: a fixing portion attached to a distal end of the femur; a cutting guide portion aligned with respect to the fixing portion; and a connecting portion connected to one side of the fixing portion, in which the connecting portion comprises a laser device aligning the fixing portion using a laser beam emitted by the laser device, thereby enabling an easy and convenient surgical operation. 
     According to a yet further embodiment of the present invention, the connecting portion may include an ML laser device emitting a laser beam toward a proximal end of the femur from a front side of the femur and an AP laser device emitting a laser beam toward the proximal end of the femur from a medial side or a lateral side of the femur, thereby facilitating alignment of the fixing portion in a medial-lateral direction and a an anterior-posterior direction. 
     According to a yet further embodiment of the present invention, the connecting portion may include an ML member extending in the medial-lateral direction and an AP member extending in the anterior-posterior direction, and the ML member and the AP member respectively include the ML laser device and the AP laser device, thereby facilitating alignment of the fixing portion in the medial-lateral direction and the anterior-posterior direction. 
     According to a yet further embodiment of the present invention, the cutting guide portion may include a frontal cutting guide portion that guides cutting of a frontal portion of the distal end of the femur and a distal cutting guide portion that guides cutting of a middle portion of the distal end of the femur, and the distal cutting guide portion may be aligned by being connected to the fixing portion via the frontal cutting guide portion. 
     According to a yet further embodiment of the present invention, the fixing portion may include a rotation detection means that enables numerical verification for a rotation state of the fixing portion during alignment of the fixing portion, which is performed by using a laser beam, thereby facilitating precise, accurate, and fast alignment of the fixing portion and enabling an accurate surgical operation by preventing the fixing portion from being displaced after the fixing portion is aligned. 
     According to a yet further embodiment of the present invention, the rotation detection means may be a gyro sensor. 
     According to a yet further embodiment of the present invention, the surgical instrument may further include a tibia resection device for resecting a tibia, in which the tibia resection device includes a laser device, whereby the surgical instrument enables an easy and fast surgical operation by eliminating the need of using an extramedullary aligner during alignment of the tibia for resection of the tibia 
     According to a yet further embodiment of the present invention, in the surgical instrument, the tibia resection device may include a tibia cutting guide portion attached to a frontal end of the tibia and a connector combined with the tibia cutting guide portion, and the connector may include a laser device emitting a laser beam to a distal end of the tibia, whereby the surgical instrument facilitates alignment of the tibia cutting guide portion. 
     According to a yet further embodiment of the present invention, in the surgical instrument, the tibia cutting guide portion may include a rotation detection means, thereby enabling numerical verification for an alignment state of the tibia cutting guide portion when the tibia cutting guide portion is aligned with a laser beam, whereby the surgical instrument enables precise, accurate, easy, and fast alignment of the tibia cutting guide portion. 
     According to a yet further embodiment of the present invention, there is provide a surgical instrument for artificial joint replacement, the surgical instrument including a rotation detection means, thereby enabling a precise, accurate, and easy surgical operation by numerically precisely controlling a resection position of a bone and an installation position of an implant. 
     According to a yet further embodiment of the present invention, the surgical instrument may further include: a reference rotation detection means providing a reference position used to detect a rotation angle of a component of the surgical instrument; and an operation rotation detection means detecting the rotation angle of the component with respect to the reference rotation detection means. 
     According to a yet further embodiment of the present invention, the surgical instrument may further include a detector having a shape corresponding to a tibial component trial and a resected surface of the tibia, in which the detector includes an operation rotation detection means and a pressure detection means and is inserted between the tibial component trial and an insert trial, thereby enabling an easy and fast surgical operation by allowing numeral verification for medial and lateral balance and for a rotation degree of the trials. 
     According to a yet further embodiment of the present invention, the detector may be provided with a positioning recess in one surface thereof, and the tibial component trial may be provided with a positioning protrusion at one surface thereof to position the detector, in which the detector has the positioning recess at a position corresponding to the positioning protrusion so that the detector is promptly and easily positioned on the tibial component trial and is prevented from slipping after being placed on the tibial component trial. 
     According to a yet further embodiment of the present invention, the surgical instrument may include a femoral component trial and a balance checker inserted between the tibia and the femur to check medial and lateral balance, in which the balance checker includes a detector having the a shape corresponding to the resected surface of the tibia, and the detector includes an operation rotation detection means and a pressure detection means to allow numerical verification for medial and lateral balance and a rotation state when the balance checker is inserted between the tibia and the femur, thereby enabling an easy and fast surgical operation. 
     According to a yet further embodiment of the present invention, the balance checker may include a first insertion portion provided with an accommodation recess in which the detector is accommodated, the detector may be provided with a knob means at a periphery portion thereof, and the accommodation recess may be provided with an outer recess at a position corresponding to the knob means such that the detector is easily removable from the balance checker. 
     According to a yet further embodiment of the present invention, the balance checker may include a second insertion portion composed of an upper plate and a lower plate such that the detector is inserted between the upper plate and the lower plate, whereby the detector is inserted into and removed from the balance checker in a sliding manner. 
     According to a yet further embodiment of the present invention, the balance checker may be equipped with a laser device at one side thereof, thereby allowing easy verification for an alignment state of the balance checker. 
     According to a yet further embodiment of the present invention, the detector may be equipped with a battery for supplying power to operate the operation rotation detection means and the pressure detection means, and the battery may be charged through a wireless charging method. 
     According to a yet further embodiment of the present invention, the battery may be detachably mounted in the detector. 
     According to the present invention, it is possible to obtain advantages described below due to the preferred embodiments, the structures to be described below, and combinations and applications of the embodiments or structures. 
     According to the present invention, since a surgical instrument includes a laser device, it is possible to easily and promptly align components of the instrument, thereby reducing a burden to a surgeon and providing effects advantageous for recovery of a patient. 
     According to the present invention, since the surgical instrument aligns a femur resection device for resecting a femur with a laser beam, it is not necessary to drill an intramedullary hole in the femur, thereby preventing bone cells from being damaged and thereby minimizing complications such as infection or a fat embolism. 
     According to the present invention, since the surgical instrument aligns a femur resection device for resecting a femur with a laser beam, it is not necessary to use additional devices having large sizes. Therefore, an operation process is simplified and sped up, which is advantageous for recovery of a patient and reduces a burden to a surgeon. 
     According to the present invention, since the surgical instrument uses two laser devices during alignment of a femur, a coronal plane alignment and a sagittal plane alignment can be easily and promptly performed. Therefore, a burden to a surgeon is reduced, and a precise and accurate alignment is possible. 
     In addition, since the femur resection device includes a rotation detection means, the rotation state of a fixing portion can be verified with a specific numerical value, which reduces a burden to a surgeon, facilitates a surgical operation, and enables an easy, precise, and accurate alignment. 
     In addition, since a tibia resection device for resecting a tibia is aligned with a laser beam, it is not necessary to use an additional extramedullary aligner, which improves space utilization efficiency and speeds up a surgical operation, thereby reducing a burden to a surgeon and being advantageous for recovery of a patient. 
     In addition, since the tibia resection device includes a rotation detection means that enables numerical verification for an alignment state of the tibia resection device, a burden to a surgeon is reduced, a surgical operation is facilitated, and a precise and accurate alignment is possible. 
     In addition, the surgical instrument includes a detector having a shape corresponding to that of the resected surface of the tibia, and the detector includes a rotation detection means. Therefore, a rotation state of an implant can be precisely verified with a specific numerical value during alignment of an implant. Thus, a burden to a surgeon is reduced, a surgical operation is facilitated, and a precise and accurate alignment is possible. 
     In addition, the detector includes a pressure detection means. Therefore, medial and lateral force balance and pressure distribution can be precisely verified with specific numerical values. Thus, a burden to a surgeon is reduced, a surgical operation is facilitated, and a precise and accurate alignment is possible. 
     In addition, the detector has a knob means to be held for movement. Therefore, the detector can be easily installed and removed by holding the knob means. 
     In addition, the surgical instrument includes a balance checker in which the detector is accommodated, and the balance checker includes a laser device. Therefore, axial alignment of an implant is verified during verification for balance using a laser beam, which enables an easy and fast surgical operation. 
     In addition, since a battery in the detector can be charged in a wireless charging manner, an operation can be conveniently performed in a short time. 
     In addition, since the battery is detachably mounted in the detector, the battery can be conveniently charged. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view illustrating a state in which a hole is drilled in a femur such that an intramedullary rod (IM rod) can be inserted into the hole of the femur, according to a conventional art; 
         FIG. 2  is a perspective view illustrating a state in which various components of a surgical instrument are arranged to resect a portion of the femur after the intramedullary rod is inserted into the hole of the femur, according to the conventional art; 
         FIG. 3  is a side view illustrating a state in which a cutting guide portion is aligned using an extramedullary alignment member to resect a portion of a tibia, according to the conventional art; 
         FIG. 4  is a side view illustrating a state in which axial alignment is verified using an additional alignment member during verification of balance which is performed with a balance checker, according to the conventional art; 
         FIG. 5  is a perspective view illustrating a state in which a fixing portion is attached to a femur, according to one embodiment of the present invention; 
         FIG. 6  is a perspective view illustrating principles of connecting a connecting portion to the fixing portion according to one embodiment of the present invention; 
         FIG. 7  is a side view illustrating a process of aligning the axis of a femur using a laser beam according to one embodiment of the present invention; 
         FIG. 8  is a front view illustrating the process of aligning the axis of the femur using the laser beam according to one embodiment of the present invention; 
         FIG. 9  is a perspective view illustrating a process of combining a cutting guide portion with the fixing portion according to one embodiment of the present invention; 
         FIG. 10  is a front view illustrating a process of attaching a tibia resection device to a tibia and aligning the tibia resection device with the axis of the tibia using a laser beam according to one embodiment of the present invention; 
         FIG. 11  is a side view illustrating a side view illustrating the process of attaching the tibia resection device to the tibia and aligning the tibia resection device with the axis of the tibia using the laser beam according to one embodiment of the present invention; 
         FIG. 12  is a side view illustrating a state in which the balance checker according to one embodiment of the present invention is inserted and the knee joint is flexed; 
         FIG. 13  is a side view illustrating a state in which the knee joint in which the balance checker is mounted is extended; 
         FIG. 14  is an exploded perspective view illustrating the balance checker and a detector according to one embodiment of the present invention; 
         FIG. 15  is an exploded perspective view illustrating a balance checker and a detector according to another embodiment of the present invention; 
         FIG. 16  is an exploded perspective view illustrating a trial and the detector according to one embodiment of the present invention; 
         FIG. 17  is an exploded perspective view illustrating an insert trial and the detector according to one embodiment of the present invention; 
         FIG. 18  is a bottom exploded perspective view illustrating the trial and the detector according to one embodiment of the present invention; 
         FIG. 19  is a perspective view illustrating a process of verifying balance using the trial and the detector in a state in a knee joint is extended, according to one embodiment of the present invention; 
         FIG. 20  is a perspective view illustrating a process of verifying balance using the trial and the detector in a state in which a knee joint is flexed, according to one embodiment of the present invention; 
         FIG. 21  is a perspective view illustrating a process of charging of the battery using a whole detector mounted with battery which is placed on charging means according to one embodiment of the present invention; and 
         FIG. 22  is a perspective view illustrating a process of charging of battery using battery which is placed on charging means according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereinbelow, a surgical instrument for artificial joint replacement according to the present invention will be described with reference to the accompanying drawings. Like reference numbers refer to like elements throughout the drawings. Detailed descriptions of known functions and configurations which have been deemed to obscure the gist of the present invention will be omitted below. Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Next, a surgical instrument for artificial joint replacement will be described in detail with reference to the accompanying drawings. 
     With reference to  FIGS. 6, 11, 12, and 17 , according to one embodiment of the present invention, a surgical instrument S includes a femur resection device  1 , a tibia resection device  3 , a detector  8 , a balance checker  5 , and a trial  7 . 
     With reference to  FIGS. 5, 6, and 9 , the femur resection device  1  includes a fixing portion  11  attached to a distal end  913  of a femur  91 , a connecting portion connected to the fixing portion  11 , a frontal cutting guide portion  13  connected to the fixing portion  11 , and a distal cutting guide portion  15  connected to the frontal cutting guide portion  13 . 
     With reference to  FIG. 5 , the fixing portion  11  which is a component for aligning the cutting guide portions  13  and  15  with respect the femur  91  is attached to the distal end  913  of the femur  91 . The fixing portion  11  includes a distal fixation hole  111  to be engaged with the distal end  913  of the femur  91 , a first connection hole  113  to be engaged with the frontal cutting guide portion  13  and the connecting portion  17 , a first locking means  115  for locking a member inserted into the first connection hole  113 , and a fixing portion rotation detection means  117  for detecting a rotation state of the fixing portion  11 . 
     The distal fixation hole  111  is a hole through which a fixing portion fixing means  112  used to attach the fixing portion  11  to the distal end  913  of the femur  91  is inserted. The distal fixation hole  11  is composed of a distal center fixation hole  1111  disposed at a center portion of the fixing portion, a distal lopsided elongated hole  1113  disposed at one side of the fixing portion and elongated in a vertical direction, and a distal lopsided fixation hole  1114  disposed at the opposite side of the distal lopsided elongated hole  1113  and having a circular shape. 
     The first connection hole  113  is a hole extending through the fixing portion  11  in an anterior-posterior direction. A first connection member  131  of the frontal cutting guide portion  13  or a connection member  173  of the connecting portion  17  is selectively inserted into the first connection hole  113 . The first locking means  115  is a component for securely fixing the first connection member  131  or the connection member  173  inserted into the first connection hole  113  in a screw-locking manner. 
     The fixing portion rotation detection means  117  is structured to detect a numerical value of the axial alignment state when the fixing portion  11  is attached to the distal end  913  of the femur  91 . The fixing portion rotation detection means  117  may be a sensor that detects a rotation angle by measuring an angular speed or an angular acceleration. Preferably, the fixing portion rotation detection means  117  may be a gyro sensor. Since the rotation state of the fixing portion  11  is detected by the rotation detection means  117 , when the fixing portion  11  is aligned using laser devices (denoted by reference numbers  1759  and  1773  in  FIG. 6 ), which will be described below, it is possible to verify the rotation state of the fixing portion  11  with a numerical value during alignment of the fixing portion  11 . Therefore, a precise and accurate alignment is possible, which reduces a surgeon&#39;s stress. In addition, it is possible to detect a displacement of the fixing portion  11  after the alignment of the fixing portion  11  is performed once. Therefore, a precise and accurate resection of the femur is possible. The fixing portion rotation detection means  117  needs to detect a rotation angle of the fixing portion with respect to the femur  91 . Therefore, it is preferable that an additional rotation detection means is installed on the femur  91 . 
     The rotation detection means  117  may further include a communication device to send the rotation state of the fixing portion  11  to an external display device. Therefore, the rotation state of the fixing portion  11  can be verified using the external display device. The fixing portion  11  is a small device. Therefore, it is difficult for a surgeon to precisely observe the state of the fixing portion  11  when it is installed on a small surgical area. For this reason, when the fixing portion  11  communicates with the external display device, the surgeon can clearly observe the rotation state of the fixing portion  11  due to an enlarged image or numerical information displayed on the external display device. Therefore, the surgeon can easily, precisely, and accurately align the fixing portion with respect to the femur. 
     With reference to  FIG. 6 , the connecting portion  17  is a component used to connect a laser device to the fixing portion for fast and easy alignment of the fixing portion  11 . The connecting portion  17  includes a connection hole insertion member  171  to be inserted into the first connection hole  113 , the connection member  173  extending from one side of the connection hole insertion member  171  at a predetermined angle, an ML member  175  connected to the connection member  173  and extending in a medial-lateral direction, and an AP member  177  connected to a portion of the ML member  175  and extending in the anterior-posterior direction. 
     The connection hole insertion member  171  is a component that is inserted into the first connection hole  113  of the fixing portion  11  to securely fix the connecting portion  17  at a predetermined position. Preferably, there are two connection hole insertion members  171 , thereby preventing the connecting portion  17  connected to the fixing portion  11  from being axially rotated. 
     The connection member  173  is a component that connects the connection hole insertion member  171  and the ML member  175  to each other. The connection member  173  includes a first connection member  1731  extending in a proximal-distal direction of the femur  91  and a second connection member  1773  extending from an end of the first connection member  1731  in the anterior-posterior direction. There are also two connection members  173  each including the first connection member  1731  and the second connection member  1733  like the connection hole insertion members  171 . 
     The ML member  175  extends from an end of the connection member  173  in the medial-lateral direction. The ML member  175  includes an ML member connection means  1757  and an ML laser device  1759  combined with the ML member connection means  1757 . 
     The ML laser device  1759  emits a laser beam in a direction from a front side  9131  of the distal end  913  of the femur  91  to the proximal end  911  of the femur  91 , to help the fixing portion  11  to be fixed at a correct position. The laser beam travels along the front surface of the femur  91 , thereby preventing the fixing portion  11  from deviating, in a medial direction or a lateral direction, from the mechanical axis of the femur  91  and from being fixed in a misaligned state. The principles of the alignment are shown in  FIG. 8  in detail. With reference to  FIG. 8 , alignment between the laser beam and the mechanical axis of the femur  91  on the coronal plane can be easily verified. 
     The AP member  177  extends from an end of the ML member  175  in the anterior-posterior direction. The AP member  177  may include an AP member connection means  1771  and an AP laser device  1773  combined with the AP member connection means  1771 . 
     The AP laser device  1773  emits a laser beam in a direction from one side surface of the distal end  913  of the femur  91  to the proximal end  911  of the femur  91 , thereby helping the fixing portion  11  to be fixed at a correct position. The laser beam travels along one side surface of the femur  91 , thereby preventing the fixing portion  11  from deviating in an anterior direction or a posterior direction, from the axis of the femur  91 . The principles of the alignment are shown in  FIG. 7 . With reference to  FIG. 7 , since the laser beam travels along one side of the femur  91 , it is possible to easily verify the alignment of the fixing portion with respect to the femur  91  on the sagittal plane. 
     With reference to  FIG. 9 , the frontal cutting guide portion  13  is a component that guides cutting of the frontal end of the femur  91  and is fixed to the fixing portion  11  that is attached to the distal end  913  of the femur  91  after being aligned with respect to the fixing portion by using the ML laser and the AP laser. The frontal cutting guide portion  13  includes the first connection member  131  to be inserted into the first connection hole  113 , a frontal cutting guide slot  133  for guiding cutting of the frontal end, and a second connection member  135  that guides a position of a cutting saw within the frontal cutting guide slot  133 . 
     The first connection member  131  is inserted into the first connection hole  113 , thereby aligning and fixing the frontal cutting guide portion  13  with the fixing portion  11  and at a correct position. There may be two first connection members  131  to prevent axial rotation of the frontal cutting guide portion  13 . 
     The frontal cutting guide slot  133  is an elongated hole in which a cutting device such as a cutting saw moves, thereby guiding the cutting device that cuts away a front portion of the femur. 
     The second connection member  135  extends in the direction from the distal end to the proximal end of the femur  91 , and is inserted into a first connection recess  151  of the distal cutting guide portion  15  described below. The second connection member  135  connects the distal cutting guide portion  15  to the fixing portion  11  that is preliminarily aligned by using a laser beam, thereby aligning the distal cutting guide portion  15 . 
     The distal cutting guide portion  15  is a component that guides cutting of the distal end  913  of the femur and is combined with the frontal cutting guide portion  13 . The distal cutting guide portion  15  includes the first connection recess  151 , a distal cutting guide slot  153 , and a frontal fixation hole  155 . 
     The first connection recess  151  is an element into which the second connection member  135  is inserted such that the distal cutting guide portion  15  is automatically positioned at a correct position. 
     The distal cutting guide slot  153  is also an elongated hole in which a cutting device such as a cutting saw moves to cut away a distal portion of the femur  91 , like the frontal cutting guide slot  133 . 
     The frontal fixation hole  155  is an element used to fix the distal cutting guide  15  to the frontal end of the tibia  93 , and includes a frontal center fixation hole  1551  and a frontal inclined fixation hole  1553 . 
     The frontal center fixation hole  1551  is a portion into which a pin used to fix the distal cutting guide portion  15  that is properly aligned is inserted before the frontal cutting guide portion  13 , which is connected to the fixing portion to resect the distal end  913  of the femur  91 , is removed. The frontal inclined fixation hole  1553  is an oblique hole inclined with respect to the anterior-posterior direction to securely fix the distal cutting guide portion  15  at a specific position of the tibia  93  such that cutting of the tibia  93  is guided by the distal cutting guide portion  15 . In order to securely fix the distal cutting guide portion  15  from which the frontal cutting guide portion  13  is removed to the front surface of the tibia  93 , three or more pins need to be inserted into the fixation holes including the frontal center fixation hole and the frontal inclined fixation hole  1553 . 
     With reference to  FIGS. 10 and 11 , the tibia resection device  3  includes the tibia cutting guide portion  31  attached to the frontal end of the tibia  93  and a connector  33  attached to the tibia cutting guide portion  31 . 
     The tibia cutting guide portion  31  is a component that guides cutting of the proximal end  931  of the tibia  93 . The tibia cutting guide portion  31  includes a tibia fixation hole  311  used to fix the tibia cutting guide portion  31  to the tibia  93 , a tibia cutting guide slot  313 , and a guide portion rotation detection means  315 . 
     The tibia fixation hole  311  is a hole provided to fix the tibia cutting guide portion  31  to the tibia  93 , and the tibia cutting guide portion  31  preferably includes three or more tibia fixation holes  311 . 
     Similarly with the frontal cutting guide slot  133 , the tibia cutting guide slot  313  is an elongated hole in which a cutting device, such as a cutting saw, to resect the proximal end  931  of the tibia  93  is inserted to move in a predetermined direction. 
     The guide portion rotation detection means  315  is a component to measure a numerical value of an axial alignment state when the tibia cutting guide portion  31  is fixed to the proximal end  931  of the tibia  93 . Preferably, the guide portion rotation detection means  315  is a gyro sensor. The detection means  315  may further include a communication device to communicate with an external display device so that a specific numerical value of the rotation state of the tibia cutting guide portion  31  can be checked from the external display device. When performing knee joint replacement, since a surgical area is small, it is difficult for a surgeon to clearly observe the surgical area. However, when the surgical area is displayed on the external display device, a surgeon can clearly and precisely observe and check the rotation state of the tibia cutting guide portion and can easily and accurately align the cutting guide portion with a less burden. Due to the rotation detection means described above, when the tibia cutting guide portion  31  is aligned using a laser and rotated for alignment, numerical verification is possible. Furthermore, during the resection of the tibia following the alignment and fixation of the cutting guide portion, it is possible to detect rotation or twisting of the tibia cutting guide portion  31 , thereby enabling an accurate resection. Since the guide portion rotation detection means  315  needs to detect a relative rotation angle of the cutting guide portion with respect to the tibia  93 , an additional rotation detection means is preferably installed on the tibia  93 . 
     The connector  33  is combined with the tibia cutting guide portion  31  and is equipped with a tibia laser device  3311  on one side surface thereof. 
     The tibia laser device  3311  assists a surgeon in positioning the tibia cutting guide portion  31  at a correct position when fixing the tibia cutting guide portion  31  to the tibia  93 . With reference to  FIG. 11 , the tibia laser device  3311  is installed in front of the tibia  93  and emits a laser beam toward the distal end  933  from the proximal end  931 . Accordingly, the tibia laser device  3311  prevents the tibia cutting guide portion  31  from rotating in a medial direction or a lateral direction on the coronal plane and from being fixed at a wrong position. The principles of this alignment are shown in  FIG. 10 . With reference to  FIG. 10 , a surgeon rotates the tibia cutting guide portion  31  in the medial direction or the lateral direction while checking whether a travel direction of a laser beam is coincident with the axis of the tibia  93  until axis of the tibia becomes coincident with the travel direction of the laser beam. In this way, the tibia cutting guide portion is properly aligned. Therefore, an axial alignment process is easily performed in a short time, thereby reducing a burden to a surgeon, shortening an overall operation time, and helping recovery of a patient. 
     With reference to  FIG. 14 , the detector  8  is inserted between the distal end  913  of the femur  91  and the proximal end  931  of the tibia  93  to detect a rotation angle of an implant and a pressure applied to the implant. The detector  8  is a thin plate having a shape similar to or the same as that of the resected surface of the tibia  93 . The detector  8  is provided with a knob means  81 , a positioning recess  83 , an operation rotation detection means  85 , a pressure detection means  87 , and a battery  88 . 
     The knob means  81  is formed at the outer periphery of the detector  8 . Since the knob means  81  is formed to protrude from the outer periphery of the detector  8 , the detector  8  can be conveniently moved by holding the knob means  81  when the detector  8  is mounted on and removed from the balance checker (refer to reference number  5  in  FIG. 16 ) or a tibial component trial (refer to reference number  73  in  FIG. 17 ). 
     The positioning recess  83  is a recessed portion having a predetermined depth and is provided in one surface of the detector  8 . Preferably, the positioning recess  83  is formed in a center portion of a lower surface of the detector  8 . The positioning recess  83  is engaged with a positioning protrusion  7311  (described below) of the tibial component trial  83 , thereby preventing the detector  8  from escaping when verifying the rotation and pressure of trials  7 . 
     The operation rotation detection means  85  provided in or on one surface of the detector  8  detects a rotation state of the trial  7  and provides a numerical value of the rotation state. Preferably, the operation rotation detection means  85  is a gyro sensor and is equipped with a communication device so that the numerical value of the rotation state of the trial  7  can be checked using an external display device. A surgical area in an actual knee joint replacement operation is very small, so it is difficult for a surgeon to clearly verify the rotation state of the trial with eye. Therefore, the external display device is connected to the detector  85  to clearly show the rotation state of the trial. Therefore, a surgeon can easily perform an alignment between the bones and the surgical instrument with a less burden. 
     In addition, since the operation rotation detection means  85  needs to detect a relative rotation state of components of the surgical instrument with respect to the tibia  93  or the femur  91 , the tibia  93  or the tibial component trial  73  is mounted with a reference rotation detection means serving as a reference position for detecting a rotation angle. Alternatively, the reference rotation detection means may be mounted on the femur  91  or the femoral component trial  71 . Further alternatively, both the tibia (or the tibial component trial) and the femur (or the femoral component trial) may be provided with respective reference rotation detection means. This will be described in more detail below. 
     When the detector  8  is inserted between the femur  91  and the  93 , the pressure detection means  87  detects the force per unit area applied to the femur  91  and the tibia  93  to obtain medial and lateral force balance. The pressure detection means may be a piezoelectric element using a piezoelectric effect, a strain gauge, a load cell, or the like. In this case, preferably, the detector may include a communication device to communicate with an external display device, thereby enabling a surgeon to verify the pressure distribution using the external display device, in the form of numerical numbers. Therefore, unlike a conventional art in which the medial and lateral force balance and the pressure distribution are checked depending on a surgeon&#39;s experience and sensation, according to the present invention, a surgeon can precisely verify the balance and pressure distribution with specific numerical values displayed on the display device, so that a verification burden to a surgeon is reduced and a precise, accurate, and fast operation is possible. 
     The battery  88  is a power supply for the pressure detection means  87 , the rotation detection means  85 , and the communication device, and is provided in a front portion of the detector  8  as shown in  FIG. 14 . The battery  88  may be removably mounted in the detector  8  or unitarily embedded in the detector  8 . In the case in which the battery  88  is removably mounted, it is convenient in that the battery  88  can be separately charged. This advantage will be described later. 
     With reference to  FIGS. 12 to 16 , the balance checker  5  is a component to check balance between the distal end  913  of the femur  91  and the proximal end  931  of the tibia  93 . The balance checker  5  includes an insertion portion  51  and an extension  53  extending from the insertion portion  51 . 
     As the insertion portion  51 , there are two types respectively called a first insertion portion  511  and a second insertion portion  513 . 
     The first insertion portion  511  has a flat plate shape similar to the shape of the resected surface of the tibia  93  like the detector  8 . The first insertion portion  511  is slightly larger than the detector  8 . As the first insertion portion  511 , there may be two first insertion portions that are provided at respective ends of the extension  53 . With reference to  FIG. 14 , each first insertion portion  511  has an accommodation recess  5111  in an upper surface thereof. 
     With reference to  FIG. 14 , the accommodation recess  5111  is a recessed portion having a predetermined depth and a shape corresponding to the detector  8  to accommodate the detector  8 . The first insertion portion  511  is further provided with an outer recess  5111   a  at one side of the accommodation recess  5111  such that the knob means  81  of the detector  8  can be received in the outer recess  5111   a  when the detector  8  is accommodated in the accommodation recess  5111  of the first insertion portion  511 . 
     With reference to  FIG. 15 , the second insertion portion  513  is composed of an upper plate  5131  and a lower plate  5133  having a shape similar to the shape of the resected surface of the tibia  93 , and an insertion gap  5135  is provided between the upper plate  5131  and the lower plate  5133 . The insertion gap  5135  is a space into which the detector  8  is inserted to detect the pressure and the rotation angle. The detector  8  slides into the insertion gap  5135  when it is mounted. In the case of installing the detector  8  in a sliding manner, it is not necessary to mount the detector  8  before installing the balance checker  5 . That is, the balance checker  5  is first installed between the femoral component trial  71  and the tibia  93 , and afterwards the detector  8  is inserted into the balance checker  5 . In this case, since the detector  8  has the knob means  81 , the detector  81  can be easily inserted and removed. For easy installation and removal of the detector  8 , the insertion gap  5135  is deeply recessed in a position where the knob means  81  is located. Since the detector  8  needs to detect the pressure applied thereto in a state in which it is interposed between the upper plate  5131  an and the lower  5133 , the upper plate  5131  and the lower plate  5133  are preferably made of a soft material that can be slightly deformed when pressed. 
     The extension  53  is connected between the two insertion portions  51  and provided with a checker laser device  531  at a middle portion thereof. 
     The checker laser device  531  is disposed in front of the tibia  93  when the insertion portion  51  is inserted between the femur  91  and the tibia  93 , and emits a laser beam in a direction from the proximal end  931  to the distal end  933 . The laser beam is used to check whether the balance checker  5  including the insertion portion  51  is well aligned with the bone. This alignment checking process is shown in  FIG. 13 . Next, the aligned knee joint undergoes medial and lateral balance checking while the knee joint is extended (see  FIG. 16 ) and flexed (see  FIG. 12 ). 
     With reference to  FIGS. 17 to 20 , the trial  7  includes a femoral component trial  71 , a tibial component trial  73 , and an insert trial  75 . 
     The femoral component trial  71  is attached to the resected surface of the femur  91  and has the same shape as a femoral component serving as a cartilage. As described above, the femoral component trial  71  may include the reference rotation detection means  77 . 
     The tibial component trial  73  is attached to the resected surface of the proximal end  931  of the tibia  93  and has the same shape as a tibial component serving as a cartilage. The tibial component trial  73  may include the positioning protrusion  7311  on an upper surface  731  thereof. The tibial component trial  73  may further include the reference rotation detection means  77 . 
     The positioning protrusion  7311  is engaged with the positioning recess (refer to reference number  83  in  FIG. 18 ) of the detector  8 , thereby preventing the detector  8  from being separated from the trial  7  when the pressure and rotation of the trial  7  is checked with the detector  8 . 
     The insert trail  75  is disposed between the femoral component trial  71  and the tibial component trial  73  and functions like a bearing. The insert trial  75  has an insert trial accommodation recess  751  in a lower surface thereof. 
     The insert trial accommodation recess  751  is a cavity to accommodate the detector  8 . Therefore, the insert trial accommodation recess  751  has the same shape as the contour of the detector  8 . An outer recess  751   a  is provided at one side of the insert trial accommodation recess  751  so that the knob means  81  of the detector  8  can be received in the outer recess  751   a.    
     Next, a process of aligning a resection device for resecting a bone using the surgical instrument S described above during artificial knee joint replacement will be described. 
     With reference to  FIGS. 5 to 9 , the fixing portion  11  is attached to the distal end  913  of the femur  91 . Next, the fixing portion fixing means  112  is inserted into the distal center fixation hole  1111  for temporary fixation. 
     Next, the connecting portion  17  is connected to the fixing portion  11  by inserting the connection hole insertion member  171  of the connecting portion  17  into the first connection hole  113  of the fixing portion  11 . The ML laser device  1758  combined with the connecting portion  17  guides medial-lateral alignment on the coronal plane as illustrated in  FIG. 7 , and the AP laser device  1773  guides anterior-posterior alignment on the sagittal plane as illustrated in  FIG. 8 . At this time, the fixing portion rotation detection means  117  detects a rotation angle of the fixing portion  11  with respect to the femur  91  and displays the rotation angle on the external display device. A surgeon adjusts the rotation angle of the fixing portion  11  while checking the rotation angle displayed on the display device. Therefore, a precise and accurate operation is possible and a burden to a surgeon for verification of rotation of the fixing portion is reduced. 
     After the position adjustment of the fixing portion  11  is finished, another fixing portion fixing means  112  is inserted into the distal lopsided elongated hole  1113 . Since the distal lopsided elongated hole  1113  is a long hole extending in a vertical direction, even when the fixing portion fixing means  112  are respectively inserted into the distal center fixation hole  1111  and the distal lopsided elongated hole  1113 , the fixing portion  11  can be slightly rotated. When the position of the fixing portion  11  is finally determined after the rotation of the fixing portion  11  is finely adjusted, a further fixing portion fixing means  1114  is inserted into the distal lopsided fixation hole  1114 , so that the fixing portion  11  is securely fixed not to be displaced. Since the fixing portion  11  is fixed by the three fixing portion fixing means, the fixing portion  11  can be securely fixed. The finished state of this process is shown in  FIG. 9 . 
     Next, with reference to  FIG. 9 , the connecting portion  17  is removed, and the first connection member  131  of the frontal cutting guide portion  13  is engaged with the first connection hole  113 . Next, a cutting device such as a cutting saw is inserted into the frontal cutting guide slot  133  to resect a front portion of the femur. At this time, the fixing portion rotation detection means  117  detects whether the frontal cutting guide portion  13  combined with the fixing portion  11  is rotated by the force attributable of motion of the cutting device. 
     Next, the position of the distal cutting guide portion  15  is determined by inserting the second connection member  135  into the first connection recess  151  of the distal cutting guide portion  15 . Next, fixing means such as pins are inserted into the frontal center fixation hole  1551  and the frontal inclined fixation hole  1553  such that the distal cutting guide portion  15  is fixed to the front side of the femur  91 , and the frontal cutting guide portion  13  is removed. Finally, a cutting device such as a cutting saw is inserted into the distal cutting guide slot  153  and the distal end  913  of the femur  91  is resected by using the cutting device. 
     In the process described above, the frontal portion is resected first and then the distal portion is resected. However, this sequence is only exemplary and can be changed. That is, the distal portion  913  may be resected first, and then the frontal portion may be resected. 
     With reference to  FIGS. 10 to 11 , the tibia cutting guide portion  31  is attached to the front side of the tibia  93  to resect the tibia  93 . A fixing pin is first inserted into the tibia center fixation hole  3111  for temporary fixation of the tibia cutting guide portion  31 , the connector  33  is attached to the tibia cutting guide portion  31 , and medial-lateral alignment on the coronal plane can be performed using a laser beam emitted by the tibia laser device  3311 . When the tibia cutting guide portion  31  is rotated while checking whether the axis of the tibia  93  is coincident with the laser beam, the guide portion rotation detection means  315  detects and sends a relative rotation angle of the tibia cutting guide portion with respect to the tibia  93  to the external display device. Therefore, a surgeon can rotate the tibia cutting guide portion  31  while checking the relative rotation angle from the external display device. Therefore, a precise and accurate surgical operation can be performed and a burden to a surgeon is reduced. 
     After the alignment of the tibia cutting guide portion is finished, a pin is inserted into the tibia inclined fixation hole  3113  to securely fix the tibia cutting guide portion  31  to the tibia. Preferably, three or more pins may be used. Next, a cutting device such as a cutting saw is inserted into the tibia cutting guide slot  313  to resect the proximal end  931  of the tibia  93 . The operation rotation detection means  315  detects and sends a relative rotation angle of the tibia cutting guide portion to the external display device. Therefore, it is possible to check whether the tibia cutting guide portion  31  is displaced by the force attributable to motion of the cutting device. 
     With reference to  FIGS. 12 to 16 , the femoral component trial  71  is attached to the resected surface of the femur  91 , and the insertion portion  51  of the balance checker  5  mounted with the detector  8  is inserted between the tibia  93  and the femoral component trial  71 . In the case in which the second insertion portion  513  is provided in the balance checker  5 , the detector  8  can be inserted into the balancer checker  5  in a sliding manner. 
     The checker laser device  531  emits a laser beam from the front side of the tibia  93  toward the distal end. Therefore, it is possible to check whether the balance checker  5  is aligned with the axis of the tibia using the laser beam. 
     Next, the knee joint is extended (see  FIG. 16 ) and flexed (see  FIG. 12 ) and the medial and lateral balance is verified. At this time, since the operation rotation detection means  85  included in the detector  8  detects a relative rotation angle of the balance checker  5  with respect to the femoral component trial  71 , a precise adjustment can be performed while checking numerical values, and thus balance verification can be reliably performed. 
     In addition, the rotation and balance between the femur  91  and the tibia  93  can be easily verified using the pressure detection means  87 . The term ‘balance’ may mean a difference in force distribution between a medial side and a lateral side of the knee joint, or a difference in force distribution between the case of extension and the case of flexion of the knee joint. When the difference in force distribution is large, the resection amount of the medial side, the lateral side, the distal side  913 , or a rear side of the femur  91  is adjusted to obtain a desired balance state. 
     The pressure detection means  87  detects the distribution of pressure and displays it on an external display device. Therefore, a surgeon can easily and quickly perform an accurate surgical operation by checking the balance from the display device. 
     With reference to  FIGS. 17 to 20 , after the femoral component trial  71  is attached to the resected surface of the femur  91  and the tibial component trial  73  is attached to the resected surface of the tibia  93 , the insert trial  75  equipped with the detector  8  that is accommodated in the accommodation recess  751  is inserted between the femoral component trial and the tibial component trial. Next, the balance is verified while extending and flexing the knee joint. At this point, the operation rotation detection means  85  included in the detector  8  detects a rotation angle of the insert trial  75  with respect to the femoral component trial  71 . Therefore, it is possible to precisely adjust the rotation angle through numerical verification, thereby accurately and reliably verifying the balance. 
     In addition, it is possible to easily numerically verify the pressure distribution in accordance with rotation angles by using the pressure detection means  87 . Herein, the balance may mean a difference in force distribution between a medial side and a lateral side of the knee joint, or a difference of force distribution between the case of extension and the case of flexion of the knee joint. When the difference in force distribution is large, the trial  7  is replaced with a larger size trial or an insertion angle of the trial is changed to obtain a suitable balance state. 
     As described above, since the pressure detection means  87  detects and sends a pressure distribution to the external display device, a surgeon can verify the balance using the information displayed on the external display device, so that the surgeon can easily perform a fast, precise, and accurate operation. 
     With reference to  FIGS. 21 and 22 , the battery  88  can be charged using an additional charging means  2 . In this case, the charging means  2  transfers electric charges to the battery  88  in a wireless manner. Specifically, when the battery  88  is placed on the charging means  2 , the battery is charged by radio frequency. 
     When the battery  88  is detachably mounted in the detector  8 , as illustrated in  FIG. 22 , only the battery  88  can be placed on the charging means  2 . However, when the battery  88  is embedded in the detector  8 , as illustrated in  FIG. 21 , the whole detector  8  mounted with battery  88  is placed on the charging means  2  for charging of the battery  88 . 
     The detailed description above is about an exemplary embodiment of the present invention. Although preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various combinations, changes, and applications thereof are possible. The preferred embodiments can be changed or modified within the scope of the concept of the invention disclosed in the specification, the scope of equivalents, and/or the range of technologies or knowledge of those skilled in the art. The preferred embodiments that have been described above are best modes to realize the technical spirit of the present invention, and diverse changes required in application and use of the invention are also possible. In consequence, the detailed description is not intended to limit the scope of the invention but the scope of the following claims should be construed as including other embodiments.