JP2014113197A - Angle measurement system and program - Google Patents

Abstract

An object of the present invention is to provide an angle measurement system and program for accurately measuring the angle around an affected area of a target patient in artificial joint replacement or osteotomy, and in particular, to provide a method for more accurately and easily measuring the angle of a joint. .
Attitude sensors 11 and 12 for detecting attitude angles in a three-dimensional space, attitude angles detected by the attitude sensors 11 and 12 are acquired, and relative angles are calculated from the acquired attitude angles. And a PC 13 for outputting a plurality of relative angles on the calculated time series.
[Selection] Figure 1

Description

  The present invention relates to an angle measurement system and program for accurately measuring an angle around an affected area of a target patient in artificial joint replacement or osteotomy.

  In wedge opening osteotomy, a device for forming a wedge-shaped opening including a specific device for identifying a cutting surface passing through the bone and a boundary line for terminating the cutting formed along the cutting surface And a method are provided. (For example, Patent Document 1)

JP 2008-529607 A

  The above-mentioned patent document describes a technique for forming an accurate incision surface for wedge opening osteotomy, but how to reproduce the exact wedge opening angle as planned after forming the incision. After that, there is no description of a technique for inserting a wedge-shaped implant or fixing an internal fixation material such as a plate.

  On the other hand, in procedures such as artificial joint replacement, the relative angle of the joints of the two bones forming the patient's joint, and the artificial joint with respect to the bone, before, during and after surgery Although it is very important to accurately grasp the installation angle of the device, it is difficult to actually perform accurate measurement depending on the joint part and the posture of the patient.

  For example, when measuring the range of motion of the hip joint using a goniometer or the like, it is usual to measure a plurality of times for accuracy with respect to three types of bending angles, inner and outer rotation angles, and inner and outer rotation angles. It is very cumbersome and burdensome for both patients and doctors.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an angle measurement system and program capable of measuring the angle of a joint part more accurately and easily. is there.

  One aspect of the present invention is the first and second angle measuring devices that respectively detect the posture angle in the three-dimensional space, and the acquisition means that acquires the posture angle detected by the first and second angle measuring devices. , Calculating means for calculating a relative angle from each posture angle of the first and second angle measuring devices acquired by the acquiring means, and outputting a plurality of time-series relative angles calculated by the calculating means. And an arithmetic output device having an output means.

  According to the present invention, the angle of the joint portion can be measured more accurately and easily.

The figure which shows the use environment of the angle measurement system in the case of measuring the angle of the movable range of the hip joint which concerns on one Embodiment of this invention. The block diagram which shows the circuit structure of the attitude | position sensor which concerns on the same embodiment. The figure explaining the attitude | position angle of the triaxial direction detected with the attitude | position sensor which concerns on the same embodiment. The flowchart which shows the processing content of the angle detection operation which PC which concerns on the same embodiment performs. The perspective view which shows the external appearance structure of the attitude | position sensor and distance sensor which concern on the modification of the embodiment. The flowchart which shows the processing content of the detection operation | movement of the angle and distance which PC which concerns on the modification of the embodiment performs. The figure which shows the application example in the wedge opening osteotomy which concerns on the modification of the embodiment.

(One embodiment)
Hereinafter, an embodiment in which the present invention is applied to an angle measurement system will be described in detail with reference to the drawings.

[Constitution]
FIG. 1 is a diagram showing an environment in which the system is used when measuring the angle of motion of the hip joint. Here, the posture sensor 11 is affixed from the outer surface along the position corresponding to the sacrum on the back side of the pelvis of the patient CL in the lateral position, and is attached to the femur approximately at the center of the front side of the right thigh. The other posture sensor 12 is similarly stuck along with an adhesive tape or the like.

  Here, the posture sensors 11 and 12 each have a rectangular parallelepiped casing as shown in the figure, and the guide rods 11a and 12a along the longitudinal direction thereof are projected. The posture sensor 11 is positioned so that the guide rod 11a of the posture sensor 11 substantially coincides with the axial direction of the sacrum of the patient CL. On the other hand, the guide rod 12a of the posture sensor 12 is positioned so as to substantially coincide with the axial direction of the femur of the patient CL.

For example, a personal computer (hereinafter referred to as “PC”) 13 connected with a wireless communication technology based on Bluetooth (registered trademark) (hereinafter referred to as “Bluetooth”), which is a short-range wireless communication standard, is used as the detection output from these attitude sensors 11 and 12. Receive and record.
The PC 13 is preinstalled with an application program for acquiring detection outputs from the attitude sensors 11 and 12, calculating the relative angle, and recording the relative angle.

FIG. 2 is a block diagram showing a configuration of functional circuits of the attitude sensors 11 and 12.
In the figure, the attitude sensor 11 (12) is configured by connecting a three-axis acceleration sensor unit 23, a key switch unit 24, and a Bluetooth communication unit 25 via the control unit 21 and a bus 22 with the control unit 21 as a center. Is done.

  Instead of the triaxial acceleration sensor unit 23, a gyro sensor, a geomagnetic sensor, or RFID (Radio Frequency IDentification) may be used.

  The control unit 21 includes a CPU, a RAM as a work memory thereof, and a non-volatile flash memory that stores an operation program and the like, and controls overall operations in the attitude sensor 11 (12).

  The triaxial acceleration sensor unit 23 detects accelerations in the triaxial X, Y, and Z directions orthogonal to each other applied to the attitude sensor 11 (12), including gravitational acceleration, and digitizes the detection signal to control the control unit 21. Output to.

  As shown in FIG. 3, in this embodiment, the longitudinal direction of the casing of the rectangular parallelepiped posture sensor 11 (12), the direction along the guide rod 11a (12a) is the Z axis, and the posture sensor 11 (12) is the patient CL. When installed along the body surface, the direction parallel to the body surface plane and perpendicular to the Z axis is defined as the X axis, and the direction perpendicular to the body surface of the patient CL is defined as the Y axis.

  The key switch unit 24 includes a marker function for marking output data at a measurement point intended by the user, in addition to a switch function for turning on / off the power of the posture sensor 11 (12).

The Bluetooth communication unit 25 transmits / receives data in accordance with the Bluetooth standard to / from the PC 13 via the antenna 26, and transmits information on the attitude angle detected at that time to the PC 13 under the control of the PC 13.
The PC 13 can be implemented by a very general well-known technique except for the fact that an application program for angle measurement, which will be described later, is installed. Therefore, illustration and description of the configuration are omitted. .

[Operation]
Next, the operation of the above embodiment will be described.
Before performing the measurement operation, the pairing setting between the PC 13 and the attitude sensors 11 and 12 is completed in advance, so that the PC 13 is a master machine and the attitude sensors 11 and 12 are both slave machines. Data can be transmitted and received within the range of class 2 (within 10 [m]).

  FIG. 4 is a flowchart showing the processing contents of the application program for angle measurement executed by the PC 13 with the posture sensors 11 and 12 installed in the patient CL as shown in FIG. Specifically, the CPU in the PC 13 reads out the application program stored in a storage medium, for example, a hard disk device, expands it on the main memory, and executes the following operations.

  At the beginning of the process, the CPU of the PC 13 determines whether or not an operation for instructing the end of the measurement has been performed (step S101). If it is determined that the operation for instructing termination has not been performed yet, it is next determined whether or not the measurement timing set in advance is reached (step S102). The process returns to S101.

  By repeatedly executing the processes of steps S101 and S102 in this way, an operation for instructing the end is performed, or the system waits for the measurement timing.

  The measurement timing can be arbitrarily changed and set by the user of the PC 13, and here, for example, it is assumed that the measurement is performed in a cycle of 0.5 [second].

  When it is determined in step S102 that the set measurement timing has been reached, the CPU requests the posture sensors 11 and 12 as slave units to detect and transmit information on posture angles at that time, In response to the request, information on the posture angle transmitted from the posture sensors 11 and 12 is acquired (step S103).

  The CPU of the PC 13 calculates the relative angle of the posture sensor 12 in the three-dimensional space with reference to the posture angle of the posture sensor 11 based on the acquired posture angle information of the posture sensors 11 and 12 (step S104). ) After the calculated angle information is recorded together with the time information at that time (step S105), the process returns to step S101 again.

  In this manner, relative angle information is continuously calculated and recorded from the posture angle information acquired from the posture sensors 11 and 12 at every measurement timing of a preset period.

  When an operation for instructing the end of the measurement is performed, the PC 13 determines the end in step S101 at that time, and the series of angle information that has been recorded so far is collected and recorded as one data file. Then, the process of FIG. 4 is terminated.

[Function and effect]
As described above, according to the present embodiment, the recording operation itself is automatically and continuously executed on the PC 13 side only by guiding the hip angle of the patient CL to be arbitrarily changed during the measurement operation. The angle can be measured more accurately and easily with reference to the pelvis.

When recording the relative angle information described with reference to FIG. 4 above, the user simultaneously performs predetermined key operations on the PC 13 in accordance with the state of the patient CL during the angle measurement, so that the marker information is displayed together with the angle information. It is good also as what can be recorded together.
Thereby, it is possible to mark on the record the time point considered to be the limit state or neutral state of flexion / internal / external rotation / internal / external rotation with respect to the hip joint of the patient CL.

(Modification of one embodiment)
Hereinafter, modifications of one embodiment of the present invention will be described in detail with reference to the drawings.

[Constitution]
In addition to the attitude sensors 11 and 12 described in FIG. 1, a distance sensor 31 shown in FIG. 5 is used.

  In FIG. 5, the distance sensor 31 has a telescope mechanism that detects, as distance information, the amount of movement along the axial direction of a columnar slide portion 31b that penetrates the first base portion 31a. The attitude sensor 11 is fixedly installed on the first base portion 31a.

  The tip of the slide portion 31b is rotatably connected to the second base portion 31d via a ball joint 31c. The attitude sensor 12 is fixedly installed on the second base portion 31d.

  A pair of hollow parallel guides 31e and 31f for fixing each base portion to the bone joint portion is provided on each end side surface of the first base portion 31a and the second base portion 31d facing each other. These parallel guides 31e and 31f are provided to pass through pins (not shown) so as to fix the first base portion 31a and the second base portion 31d to the bone joint portions with the osteotomy surface interposed therebetween.

  The configuration of the functional circuit of the distance sensor 31 is almost the same as that of the distance sensor 31 except that a detection unit using the telescope mechanism for detecting distance information is provided instead of the triaxial acceleration sensor unit 23 in FIG. Since it is the same, illustration and description thereof are omitted.

  The detection unit using the telescope mechanism detects a voltage value that changes as the slide part 31b moves in a coil built in the first base part 31a, digitizes it, and outputs it as distance information.

[Operation]
Next, the operation of a modification of the above embodiment will be described.
Before performing the measurement operation, the pairing setting between the PC 13 and the attitude sensors 11 and 12 and the distance sensor 31 is completed in advance, so that the PC 13 becomes the master machine, the attitude sensors 11 and 12, and the distance sensor 31. As both slave units, it is possible to transmit and receive data within a range of class 2 (within 10 [m]), for example.

  In addition, here, a case where wedge opening osteotomy for the tibial knee joint is executed will be described as an example. In this pre-surgery plan, the accurate setting of the incision surface, the wedge opening angle after the incision, and the distance between the posture sensors 11 and 12 when the distance sensor 31 is fixed are preliminarily determined by a three-dimensional image processing program. Assume that the shape data is calculated and stored.

  FIG. 6 shows a state in which the incision surface is accurately formed at the tibial knee joint as planned in advance, and the distance sensor 31 integrally provided with the posture sensors 11 and 12 shown in FIG. 5 is installed at the knee joint. It is a flowchart which shows the processing content of the application program for angle measurement which PC13 starts starting from.

  FIG. 7 shows a state during operation of the tibia TB on which the distance sensor 31 is installed. The portion indicated by the wavy line in the figure shows the outer shape in the vicinity of the knee intercondylar bulge immediately after the cut surface is formed (before the wedge is opened). The pair of mounting positions of the parallel guide 31e on the first base portion 31a side and the pair of mounting positions of the parallel guide 31f on the second base portion 31d side are shown in the drawing, and installed on the tibia TB. The description of the distance sensor 31 itself is not intentionally shown for the sake of explanation.

  At the beginning of the process, the CPU of the PC 13 reads out the angle information in the relative three-dimensional space of the posture sensors 11 and 12 determined in advance in the preoperative plan and the distance information between the posture sensors 11 and 12 (step S201). ).

  Next, the system waits for a preset measurement timing (step S202).

  The measurement timing can be arbitrarily changed and set by the user of the PC 13, and here, for example, it is assumed that the measurement is performed in a cycle of 1 [second].

  When it is determined in step S202 that the set measurement timing has been reached, the CPU detects posture angle information and distance information at that time for the posture sensors 11 and 12 and the distance sensor 31, which are slave devices. In response to the request, information on the posture angle and the distance information transmitted from the posture sensors 11 and 12 and the distance sensor 31 are acquired (step S203).

  The CPU of the PC 13 calculates the relative angle of the posture sensor 12 in the three-dimensional space on the basis of the posture angle of the posture sensor 11 based on the obtained posture angles of the posture sensors 11 and 12 (step S204). The degree of similarity is calculated by comparing the calculated angle information and distance information with the same information in the preoperative plan read out in step S201 (step S205).

  And after notifying by outputting loudly the pulse-like beep sound of the interval according to the calculated similarity degree and an intermittent interval (step S206), it returns to the process from said step S202 again.

  The pulsed beep sound output in step S206 is set to increase the pitch and shorten the intermittent interval, for example, every time the similarity increases.

  While repeating the processes in steps S202 to S206, the practitioner gradually opens the proximal side of the tibial TB knee joint where the intercondylar bulge is present, thereby forming a wedge-like shape as shown by hatching in FIG. Since the opening portion OP gradually increases, the relative angle of the posture sensor 12 with respect to the posture sensor 11 increases, and the distance of the posture sensor 12 with respect to the posture sensor 11 also increases.

  Therefore, the pitch of the beep sound output by the notification in step S206 is gradually increased, and the intermittent interval is shortened.

  When the similarity reaches 100 [%], that is, in a state where the wedge opening state as planned before the operation is realized, the beep sound that is notified in step S206 is the highest set pitch and continuous sound. Become.

  Therefore, the practitioner can realize the wedge opening state as planned before the operation by continuing the treatment while listening to the beep sound notified from the PC 13.

[Function and effect]
As described above, according to the modification of the present embodiment, it is possible to grasp the operation on the joint portion more accurately and easily by taking into account not only the relative angle but also the distance information.

  In addition, in the modified example of the above-described embodiment, by performing notification according to the degree of similarity to the preoperative plan at the time of the operation, it is possible to realize an operation on the joint part as per the preoperative plan.

  In the above-described embodiment and its modified examples, the case where the angles of the hip joint and the knee joint are measured using the posture sensors 11 and 12 has been described. However, the present invention is not limited to the joint, and may constitute a human body. The same can be applied to various joints. Further, by mounting the posture sensor 12 on a surgical instrument such as a surgical instrument for artificial joints, an operation as a surgical navigation device for guiding a three-dimensional surgical plan can be realized.

  In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiment includes various stages, and various inventions can be extracted by an appropriate combination of a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the effect is obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

  DESCRIPTION OF SYMBOLS 11, 12 ... Attitude sensor, 11a, 12a ... Guide rod, 13 ... Personal computer (PC), 21 ... Control part, 22 ... Bus, 23 ... 3-axis acceleration sensor part, 24 ... Key switch part, 25 ... Bluetooth communication part , 26 ... antenna, 31 ... distance sensor, 31a ... first base part, 31b ... slide part, 31c ... ball joint, 31d ... second base part, 31e, 31f ... parallel guide, TB ... tibial knee joint part.

Claims (4)

First and second angle measuring devices that respectively detect posture angles in a three-dimensional space;
Obtaining means for obtaining posture angles detected by the first and second angle measuring devices, and calculation for calculating a relative angle from each posture angle of the first and second angle measuring devices obtained by the obtaining means. And an arithmetic output device comprising an output means for outputting a plurality of relative angles on the time series calculated by the calculating means. The first and second angle measuring devices are further connected to each other in a telescopic manner, and a distance measuring device for detecting the distance between the two angle measuring devices by changing the mounting angle with one of the first and second angle measuring devices is further provided. And
In the arithmetic output device,
The acquisition means acquires the distance detected by the distance measuring device together,
The angle measuring system according to claim 1, wherein the output means outputs a plurality of relative angles on the time series calculated by the calculating means together with the distance detected by the distance measuring device. The arithmetic output device is
Preoperative plan storage means for storing the relative angle obtained in the preoperative plan;
A calculation means for calculating the degree of similarity by comparing the relative angle calculated by the calculation unit with the content stored in the preoperative plan storage unit;
2. The angle measuring system according to claim 1, further comprising notifying means for notifying according to the similarity obtained by the calculating means. A program executed by a computer built in a device that inputs detection outputs from first and second angle measuring devices that detect posture angles in a three-dimensional space,
An acquisition step of acquiring the posture angle detected by the first and second angle measuring devices;
A calculating step of calculating a relative angle from each posture angle of the first and second angle measuring devices acquired in the acquiring step;
An output step for outputting a plurality of relative angles on the time series calculated in the calculation step.

Images