JP2007202950A - Leg holding tool for surgery robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a leg holding tool which firmly fixes the knee joint of a patient without narrowing the work area of a surgery robot when performing a knee joint replacement surgical operation using the surgery robot. <P>SOLUTION: In the leg holding tool for the surgery robot which holds, by maintaining the angle of the knee joint at a predetermined angle, the leg of the patient placed on an operating table, this leg holding tool has two hinge + sliding mechanisms which can freely regulate the angle and spacing of a tibia side fixing portion which wraps the tibia by exposing the knee joint and a thighbone side fixing portion which wraps a thighbone and the operating table of each of the tibia side fixing portion and the thighbone side fixing portion, and a hinge/sliding mechanism which is connected by freely regulating the angle and spacing between the tibia side fixing portion and the thighbone side fixing portion. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lower limb gripping jig for a surgical robot that fixes a patient's knee joint in order to perform bone resection safely and accurately during an artificial knee joint replacement using a surgical robot.

  In general, for knee joint damage, artificial knee joint replacement is performed so that the joint surfaces of the distal femur and proximal tibia are replaced. In this, a metal component (femoral component) similar to the shape of the distal femur is used on the femur side, and an ultrahigh molecular weight polyethylene plate alone or in combination with a metal plate (tibial plate) on the tibia side ) To replace the knee joint.

  When replacing the artificial knee joint with the femur and tibia in artificial knee joint replacement, the femoral component and tibial bone edges are excised according to the shape of the femoral component and tibial plate placement surface, and the resection surface is removed. And fix each installation surface in close contact. This fixation can be done with or without bone cement.

  When bone cement is used, keeping the thickness of the cement layer constant brings about a stress dispersion effect and enables stable long-term fixation. Moreover, in the method which does not use bone cement, a fixing force is obtained by the anchoring effect in which the installation surface is a porous surface and the bone is naturally grown and entangled with the porous surface. In both of these fixations, high consistency between the artificial knee joint placement surface and the bone-side cut surface is important.

  In general surgery, when cutting the bone for the artificial knee joint placement surface, an instrument called a cutting guide with a slit is used, and a blade called a bone saw is inserted into the slit and the slit is used as a reference. Perform excision as a plane. At this time, accurate excision was difficult due to a gap between the slit and the bone saw or deflection during the bone saw excision.

  On the other hand, it is necessary to install the artificial knee joint at a clinically optimal position. When an installation position error occurs, the range of motion of the knee joint is limited or the soft tissue (particularly, the collateral ligament of the knee joint) is imbalanced, causing excessive stress to the knee prosthesis and causing early destruction.

  As for the position of the artificial knee joint, the position of the artificial knee joint is determined based on the experience and intuition of the doctor during operation using various instruments from the limited visual field of the knee joint. Such ambiguity may cause an error in the position of the artificial knee joint, which may cause early destruction of the artificial knee joint.

  In order to eliminate an error factor when excising the femur and tibia by this manual operation, a surgical robot (bone resection device) as exemplified in Patent Document 1 below has been devised. With this surgical robot, accurate placement of the artificial knee joint and adhesion to the bone by accurate bone resection are realized, and the long-term function of the artificial knee joint can be ensured.

  By the way, in the conventional operation, at the time of bone resection, an assistant generally pushes and fixes a patient's lower limb, and an operator performs bone resection. In excision with a surgical robot, it is necessary to secure a certain range of motion of the robot, and therefore it is difficult for an assistant to press the lower limb during the excision.

  Furthermore, in the surgical robot, since the relative relationship between the cutting position of the tool and the affected part defines the cutting surface, it is required to fix the affected part firmly and firmly after performing the positioning by the surgical robot and during the bone resection. However, it is difficult for human assistants to do so.

  Therefore, as exemplified in Patent Document 2 below, an instrument for firmly fixing the lower limb during bone resection by a surgical robot has been devised. In the method using this instrument, the bone is directly gripped by the instrument, but it is difficult to provide a mechanism having an appropriate space near the bone resection surface due to interference with the resection tool or the surgical robot. The grip portion is at a position away from the cut surface.

  In such a gripping position, the amount of skin incision increases as compared with a normal operation in order to secure a gripping part that directly grips the bone. As a result, there is a problem that healing of the affected area is delayed and, as a result, there is a high possibility of causing postoperative complications due to excessive damage of surrounding tissues.

  In addition, in a surgical robot, it is necessary to grasp the relative position between a tool for performing bone resection and an affected part. At this time, a skeleton fluoroscopic image is acquired using an X-ray fluoroscope, A matching method may be employed.

For this reason, it is necessary to fix the relative positions of the X-ray fluoroscopic apparatus, the surgical robot, and the affected part at the time of fluoroscopic image capturing. Further, in order to obtain a clear skeleton image, the relative position of the affected part and the surgical robot is accurately measured. That contributes. For this reason, it is necessary to firmly fix the affected part and transmit X-rays thereon to obtain a good fluoroscopic image.
JP 2002-306500 A Japanese Patent Laid-Open No. 2003-024338

  In the present invention, when performing bone resection for artificial knee joint replacement using a surgical robot, it is possible to safely perform the operation and reduce the amount of skin incision as much as possible by firmly fixing the knee angle to a desired value. The aim is to provide a lower limb gripping tool for achieving the accuracy of bone resection and surgery as planned by the doctor.

  On the other hand, when bone excision is performed using a surgical robot, when the technique of using an X-ray fluoroscope is used to determine the relative position of the affected part and the tip tool of the surgical robot, the affected part is firmly fixed. And it is providing the leg fixing device comprised with an X-ray highly transparent material.

  To this end, the lower limb grasping jig according to the present invention is the lower limb grasping jig for a surgical robot for grasping the patient's lower limb placed on the operating table while maintaining the knee joint angle at a predetermined angle. The lower limb grasping jig is exposed to the knee joint between the tibial side fixing part that wraps the tibia, the femoral side fixing part that wraps the femur, the tibial side fixing part, and the femoral side fixing part. It has two hinge mechanisms + slide mechanism that can freely adjust the angle and distance between the base and a hinge / slide mechanism that connects the tibial side fixing part and the femoral side fixing part by freely adjusting the angle and distance. It is characterized by this.

  As a specific example of the lower limb grasping jig, the tibial side member and the femoral side member are slidably attached to the rail attached to the side of the operating table, and the tibial side member and the thigh The base part of each hinge / sliding mechanism is connected to the bone side member, and the inflow and outflow of fluid between the tibial side fixing part and the tibia and between the femoral side fixing part and the femur described in claim 3. An inflatable and deflating bag is interposed, and the lower limb gripping jig described in claim 4 is composed of an X-ray highly transparent material.

  If the lower limb is gripped by the lower limb gripping jig according to the present invention, the affected part that is the surgical site can be firmly fixed, so that the relative position between the affected part and the surgical robot tool can be accurately defined, and the processing reaction force during resection Prevent displacement and achieve accurate bone resection. In addition, bone removal with a surgical robot makes it difficult for an assistant to intervene in the operating range of the robot. However, the present invention can safely perform bone resection without using an assistant with the lower limb gripping jig. it can.

  Further, in the conventional lower limb fixation method, in addition to the skin incision for securing the work area during the operation, it is necessary to secure an area for grasping the lower limb with a clamp-like instrument. However, in the lower limb grasping jig of the present invention, only the minimum necessary members are arranged around the affected area, and such an extra skin cut is not required, and the patient can be recovered early by minimally invasive surgery. It becomes possible.

  Further, when determining the relative position of the surgical robot and the affected area, when using a method of matching with a CAD model in a storage device using an X-ray fluoroscopic apparatus, the affected area is firmly fixed and a good fluoroscopic image is obtained. As a result, it is possible to determine an accurate relative position.

  FIG. 1 is a schematic diagram of bone resection in an artificial knee joint replacement using a surgical robot, and grasps an operating table 110, a patient 40 placed on the operating table, and a lower limb of the patient 40. A lower limb gripping jig 50 for fixing the knee angle, a surgical robot 60, and a storage device 70 are installed.

  First, at the start of the operation, the affected part (knee joint) of the patient is cut, and the distal end of the femur and the proximal end of the tibia where the artificial knee joint is placed are exposed by the minimum amount necessary for the operation.

  Next, the knee joint is fixed by the lower limb gripping jig 50 of the present invention. The fixing in this operation will be described in detail with reference to the side view of FIG.

  As shown in FIG. 2, a lower limb grasping jig 50 according to the present invention is provided with a knee joint sandwiched between a tibial fixing portion 1 that wraps the tibia and a femoral side fixing portion 2 that wraps the femur. It is done. Both the fixing portions 1 and 2 are shell-shaped half cylinders made of a rigid body, and are respectively applied to the lower tibia and the lower half of the femur. Two hinge mechanisms 3, 4 + slide mechanisms 7, 8 that can freely adjust the angle and interval with the operating table 110 are provided below the fixed portions 1, 2. The hinge mechanisms 3 and 4 + sliding mechanisms 7 and 8 of this example are crank-shaped members. The hinge mechanisms 3 and 4 are provided at the lower part, and the sliding mechanisms 7 and 8 are provided at the upper part. Furthermore, hinge / sliding mechanisms 6, 5, 14 are provided on the upper portions of the two fixing portions 1, 2 to connect the two fixing portions 1, 2 by adjusting their angles and intervals freely.

  First, the length of the jig is adjusted in accordance with the length of the patient's leg during fixation. The adjustment of the length is realized by the slide mechanisms 7 and 8 and is fixed by the fixing clamp 9. At this time, both the fixing portions 1 and 2 are portions that contribute to the fixation of the tibia and the femur, and a processing reaction force acts on the proximal portion of the large tibia and the distal portion of the femur during bone resection. Therefore, it adjusts so that both the fixing | fixed part 1 and 2 can be arrange | positioned to the proximal part of the tibia and the distal part of the femur as much as possible. By this adjustment, more firmly fixing the affected area is achieved.

  Next, the knee joint angle is adjusted. Bone resection for artificial knee joint placement at the time of artificial knee joint replacement is the front, the front slope, the distal face, the rear slope, the rear face, and the tibia side are proximal in the existing artificial knee joint It is necessary to cut one surface. In particular, as shown in the schematic diagram of FIG. 3, in an ordinary skin incision, an approach of resecting the periphery of the patella is performed. Therefore, bone resection cannot be achieved unless the posterior surface is sufficiently exposed from the distal surface of the femur.

  Therefore, in FIG. 2, the operating table 110 and the base portions 10 and 11 of the hinge mechanisms 3 and 4 can be moved relative to each other, and the hinge mechanisms 3 and 4 can be provided in the vicinity of the sole and the hip joint to adjust an arbitrary angle. The mechanism. In this embodiment, the tibial side member 12 and the femoral side member 13 that are slidably attached to the rail 111 attached to the side of the operating table 110 are connected to the base portions 10 and 11 with appropriate connecting materials, Both hinge mechanisms 3 and 4 are structured to move relative to the operating table 110.

  The reason for adopting such a configuration is that if the base portions 10 and 11 are directly attached to the operating table 110, the operation space of the operating robot 60 and the X-ray fluoroscopic apparatus is hindered by the presence space. It is. In this respect, the base portions 10 and 11 need only have a minimum space that can serve as a base for the hinge mechanisms 3 and 4.

  Further, since the flexion center at the time of knee flexion varies among individuals and the rotation center cannot be uniquely determined, the hinge / slide mechanism 5, 6 that can freely set the distance between the distal femur and the proximal tibia is provided. Provided. A rod-like member 15 extends from the femoral side hinge / sliding mechanism 5, and is configured to pass through the tibial side hinge / sliding mechanisms 6 and 14 (a configuration in which the femoral side and the tibial side are opposite to each other). May be). As a result, the angles and intervals of the fixed portions 1 and 2 can be freely adjusted, and can be set to an arbitrary position and orientation as shown in the movement schematic diagram of FIG. Finally, when the above adjustment is completed, the clamp 9 fixes the position and does not move.

  In the final fixation of the affected area, when the patient's feet were placed on the lower limb gripping jig 50 at the above fixed position, both the fixed parts 1 and 2 were also formed in a half-cylindrical shell shape. The upper lids 16 and 17 are combined to wrap the lower limbs, and a hollow bag is disposed between the fixed portions 1 and 2 and the upper lids 16 and 17 so that fluid (compressed air, water, and sand) can flow in and out. . In addition, the combined structure of the both fixing portions 1 and 2 and the upper lids 16 and 17 may have a hook and a lock mechanism.

  When the above setting is completed, as shown in the explanatory diagram of FIG. 5, the pipe 18 is inserted into the space 81 in the bag 80 having a hollow inside between the rigid fixed portions 1 and 2 and the upper lids 16 and 17 and the legs. The compressed air is further inflated by inflow, and the compression force is applied and fixed including the soft tissue 31 and the femur 30 such as leg muscles and skin. Further, when sand-like media is disposed and fixed in the space 81 in the bag 80 having a hollow inside, the amount of the media is adjusted, the bag 80 is inflated into a leg shape, and air in the bag is drawn from the tube 18. Fix the shape of the bag and fix the legs. The illustration of FIG. 5 is the case of the femur, but the same operation can be performed when the tibia 20 is fixed.

  Since the above-described fixing principle contributes to fixing a wide area of the leg, it is possible to secure a sufficient fixing force with respect to a processing reaction force during bone cutting.

  As an auxiliary fixation, under the knee joint, the vicinity of the ankle is fixed to the lower limb grasping jig using a belt or a member equivalent thereto. On the knee joint, since the leg is fixed to the patient's trunk at the hip joint, care should be taken so that the patient does not move excessively. In addition, in the femur or tibia, if rotational displacement is feared around the long axis of the bone due to processing reaction force, a pin that is supplementarily integrated with the lower limb grasping jig is attached to the proximal part of the tibia or the distal part of the femur. Auxiliary fixing may be performed by inserting into the part.

  When the above-mentioned fixation of the affected area is completed, the surgical robot 60 in FIG. 1 is installed. When using an X-ray fluoroscopy device for determining the relative position of the surgical robot tool and the affected area, the surgical robot is constructed by configuring the lower limb gripping jig with a material having high X-ray permeability such as aluminum, titanium, or resin. The reference position and the affected part skeleton image are acquired well, and the correct relative position is determined by collating with the affected part skeleton data in the storage device 70 in the surgical robot.

  Furthermore, when confirming the insertion status of other implant parts by fluoroscopy during surgery, it is advantageous in that the captured image can be acquired with the lower limbs fixed and the operation can be continued immediately without removing the lower limb grasping jig. It is.

  Through these series of operations, bone excision for replacement of an artificial knee joint by a surgical robot is performed. Also at the time of bone resection, the affected part is firmly fixed by the above method, so that high-precision bone resection by a robot and accurate placement of an artificial joint can be achieved. Needless to say, this lower limb gripping jig is also useful during manual surgery.

It is a schematic diagram of a surgery using the lower limb gripping jig for a surgical robot according to the present invention. It is a detailed view of a lower limb gripping jig for a surgical robot according to the present invention. It is explanatory drawing which showed the relationship between the knee angle in the knee arthroplasty and the possibility of bone resection. It is explanatory drawing which showed the mechanism principle of the lower limb holding jig for surgical robots of this invention. It is explanatory drawing which showed the affected part fixation principle of the lower limb holding jig for surgical robots of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tibial side fixing | fixed part 2 Femur side fixing | fixed part 3 Tibial side hinge mechanism 4 Femur side hinge mechanism 5 Femur side hinge and slide mechanism 6 Tibial side hinge and slide mechanism 7 Tibial side slide mechanism 8 Femoral side slide mechanism 9 Clamp DESCRIPTION OF SYMBOLS 10 Tibial side base part 11 Femur side base part 12 Tibial side member 13 Femur side member 14 Tibial side hinge slide mechanism 15 Bar-shaped member 16 Tibial side upper lid 17 Femoral side upper lid 18 Pipe 20 Tibial 30 Femur 31 Soft part tissue 40 Patient 50 Lower limb gripping jig 60 Surgical robot 70 Surgical robot storage device 80 Bag 81 Bag space 110 Operating table 111 Rail

Claims (4)

  This is a lower limb gripping jig for a surgical robot that holds the patient's lower limb placed on the operating table while maintaining the knee joint angle at a predetermined angle, and this lower limb gripping jig exposes the knee joint between the tibia. Two hinge mechanisms + sliding mechanisms capable of freely adjusting the angle and interval between the tibial side fixing part for wrapping and the femoral side fixing part for wrapping the femur, and the operating table of each of the tibial side fixing part and the femoral side fixing part A lower limb grasping jig for a surgical robot, comprising: a hinge / sliding mechanism for connecting the tibial side fixing portion and the femur side fixing portion by freely adjusting the angle and interval.   The tibial side member and the femoral side member are slidably attached to a rail attached to the side of the operating table, and the base portions of the hinge / sliding mechanisms are connected to the tibial side member and the femoral side member, respectively. Lower limb gripping jig for surgical robots.   The lower limb grasping jig for a surgical robot according to claim 1 or 2, wherein a bag that is inflated and contracted by fluid inflow and outflow is interposed between the tibial side fixing portion and the tibia and between the femoral side fixing portion and the femur.   A lower limb gripping jig for a surgical robot, wherein the lower limb gripping jig for a surgical robot according to any one of claims 1 to 3 is made of an X-ray highly transparent material.