Device and method for measuring toe compression force

Abstract

The present invention provides a measuring device and method that enable the measurement of toe compression force while suppressing the influence of the subject's extrinsic foot muscles and body weight. [Solution] The measuring device 10 comprises a substrate 11 with a flat upper surface, a sensor sheet 12 attached to the upper surface of the substrate 11 for measuring the distribution of compressive force from the subject's toes when the subject's toes rest on it, and a belt 13 attached to the substrate 11 for being worn on the subject's foot and supporting the substrate 11 so as to maintain contact between the sole of the subject's foot and the sensor sheet 12 when the subject's foot is lifted off the floor.

Description

Technical Field

[0001] The present invention relates to a device and method for measuring toe compressive force.

Background Art

[0002] Attention has been focused on the intrinsic foot muscles from the viewpoints of prevention and treatment of sports diseases, fall prevention, and improvement of sports performance. It is known that when the intrinsic foot muscles become stronger, the foot arch is maintained, the foot is stabilized, and the balance ability is improved. In order to quantitatively evaluate the muscle strength of such intrinsic foot muscles and utilize it for evaluation of pathological conditions and determination of training effects, a method for measuring toe muscle strength has been studied. For example, Patent Document 1 discloses a toe muscle strength measuring device that measures toe muscle strength by placing the first toe on a first force plate and the second to fifth toes on a second force plate and bending each MTP joint in this state.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the toe muscle strength measuring device of Patent Document 1 is used for measuring toe muscle strength, since the subject bends the toes in a state where the device is installed on the floor surface, when bending the MTP joint, other toe joints than the MTP joint also bend, and there is a problem that the extrinsic foot muscles have a great influence on the measured value of toe muscle strength. In addition, since the foot is placed on the force plate of the toe muscle strength measuring device installed on the floor surface and stepped on, there is also a problem that the load due to the subject's body weight affects the measured value of toe muscle strength.

[0005] This invention was made based on the above background, and aims to provide a measuring device and measuring method that can measure toe compression force while suppressing the influence of the subject's extrinsic foot muscles and body weight. [Means for solving the problem]

[0006] To achieve the above objective, the measuring device according to the first aspect of the present invention is: A substrate with a flat top surface, A sensor sheet is attached to the upper surface of the substrate and measures the distribution of compressive force applied by the subject's toes when the subject's toes are placed on it. A support member is attached to the substrate and is worn on the subject's foot, and supports the substrate so as to maintain a state in which the sole of the subject's foot is in contact with the sensor sheet when the subject's foot is lifted off the floor. It is equipped with.

[0007] The support member may be a belt attached to the substrate so as to extend in the width direction above the substrate.

[0008] The measuring device may further include a heel cup provided on the rear end side of the substrate, which contacts the subject's heel to position the subject's foot relative to the substrate.

[0009] The sensor sheet may be arranged vertically and horizontally and may be equipped with multiple sensors that measure the compressive force applied by the subject's toes at each position.

[0010] To achieve the above objective, the measurement method according to the second aspect of the present invention is: A measurement method for measuring the compression force of a subject's toes using the aforementioned measuring device, The process involves attaching the measuring device to the subject's feet so that the sensor sheet contacts the soles of the subject's feet while they are seated, A step of measuring the distribution of compressive force when the sensor sheet is compressed by flexing the MTP joint while the subject lifts their foot off the floor and does not flex any other toe joints, Includes. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a measuring device and a measuring method that can measure toe compression force while suppressing the influence of the subject's extrinsic foot muscles and body weight. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows the configuration of a measurement system according to an embodiment of the present invention. [Figure 2] This is a front view showing the configuration of a measuring device according to an embodiment of the present invention. [Figure 3] This is a plan view showing the configuration of a measuring device according to an embodiment of the present invention. [Figure 4] This figure shows an image displayed on a computer screen according to an embodiment of the present invention. [Figure 5] (a) is a diagram showing the IP extension conditions of the big toe, and (b) is a diagram showing the IP flexion conditions of the big toe. [Figure 6] This figure shows three measurement positions for the ankle joint in the example. [Modes for carrying out the invention]

[0013] The toe compression force measuring device and measuring method according to embodiments of the present invention will be described in detail below with reference to the drawings. In each drawing, the same or equivalent parts are denoted by the same reference numerals.

[0014] The measurement method according to the embodiment is a method of measuring the toe compression force by the intrinsic foot muscles by bending the MTP joint (metatarsophalangeal joint of the big toe) without bending the toe joints other than the MTP joint among the toe joints of the subject. The toe compression force is the force exerted by the bottom surface of the toe on the floor when the toe joint is bent with the toe in contact with the floor surface. In the big toe, there are two joints, the IP joint (interphalangeal joint) and the MTP joint, in order from the toe tip. In the second to fifth toes, there are three joints, the DIP joint, the PIP joint, and the MTP joint, in order from the toe tip. The intrinsic foot muscles originate in the foot and play a central role when bending the MTP joint. Therefore, by bending the MTP joint without bending the toe joints other than the MTP joint and measuring the toe compression force at that time, the muscle strength of the intrinsic foot muscles can be preferentially evaluated based on the toe compression force.

[0015] In the measurement method according to the embodiment, the toe compression force when the subject bends the MTP joint without bending the toe joints other than the MTP joint is measured using the measurement system 1. In the embodiment, not bending the toe joints other than the MTP joint is not limited to the case where these joints do not bend at all, but also includes the case where these joints bend slightly. For example, it includes the case where the rotation angle of the toe tip due to the bending of these joints is less than 10% of the rotation angle of the toe tip due to the bending of the MTP joint. Hereinafter, the configuration of the measurement system 1 according to the embodiment will be described with reference to FIG. 1.

[0016] The measurement system 1 includes a measurement device 10, a data logger 2, and a computer 3. The measurement device 10 and the data logger 2 can be communicably connected via a cable 2a, and the data logger 2 and the computer 3 can be communicably connected via a wired or wireless communication circuit.

[0017] The data logger 2 analog-digital (AD) converts the analog measurement data output from the measuring device 10, generates digital measurement data indicating the detected compression force, and stores it in an internal memory in association with the detection position and detection time of the compression force. Further, when receiving a control signal from the computer 3, it reads out the measurement data of the toe compression force stored in the internal memory and transmits it to the computer 3. The data logger 2 may be attached to the trunk using a belt so as not to affect the measured value of the toe compression force, or may be installed at a position away from the measuring device 10.

[0018] The computer 3 is, for example, a general-purpose computer. The computer 3 includes an operation device, a display, an input / output interface, a memory, and a processor, and executes various processes by executing a program stored in the memory. Specifically, when transmitting a control signal to the data logger 2, it receives the measurement data of the toe compression force from the data logger 2 and stores it in a database provided in the memory. The transmission of the control signal to the data logger 2 may be triggered by the fact that the data logger 2 and the computer 3 are communicably connected. Further, when receiving a user's instruction by the operation device, it reads out the measurement data of the toe compression force stored in the database and displays it on the display.

[0019] The measuring device 10 is attached to the foot of the subject and measures the toe compression force when the subject bends the MTP joint without bending the toe joints other than the MTP joint while lifting the foot off the floor surface. When the foot is lifted off the floor surface, it is easy to prevent the toe joints other than the MTP joint from bending when bending the MTP joint, so the influence of the extrinsic muscles of the foot can be suppressed. Further, since the load due to the weight of the subject is not applied to the sensor sheet 12, the influence of the weight on the measured value of the toe compression force can also be suppressed. Hereinafter, the configuration of the measuring device 10 according to the embodiment will be described with reference to FIGS. 2 and 3.

[0020] The measuring device 10 comprises a substrate 11, a sensor sheet 12 attached to the upper surface of the substrate 11, two belts 13 extending in the width direction (left-right direction) above the substrate 11, with each end attached to different positions on the back surface of the substrate 11, and a heel cup 14 attached to the rear end of the substrate 11. The substrate 11, belts 13, and heel cup 14 allow the sole of the foot to make stable contact with the sensor sheet 12 even when the foot is lifted off the floor.

[0021] The substrate 11 supports the sensor sheet 12 and is a plate with sufficient rigidity to not deform even when subjected to the compressive force of the subject's toes. The substrate 11 is made of a relatively lightweight material, such as resin or wood, that is resistant to elastic deformation and allows the subject to easily lift their foot off it. The top and bottom surfaces of the substrate 11 are both formed in a flat shape, and the contour of the side surface of the substrate 11 is shaped to match the shape of the sole of a human foot.

[0022] The sensor sheet 12 has numerous load detection points distributed vertically and horizontally, and measures the pressure distribution from the subject's toes when the subject's toes are placed on it. The sensor sheet 12 is attached to the upper surface of the substrate 11 so as not to shift. For example, the sensor sheet 12 is attached to the upper surface of the substrate 11 with adhesive. Because the sensor sheet 12 has the above configuration, it can measure the compression force on individual toes when the subject flexes their MTP joints.

[0023] The sensor sheet 12 is arranged vertically and horizontally and comprises pressure sensors that generate analog measurement data having a signal level corresponding to the compressive force when compressed by an object, and circuits connected to each sensor that transmit the analog measurement data generated by each sensor to the outside. The sensors are, for example, piezoelectric elements. The ends of each circuit are connected to the connector 15 via cables 12a. Cable 2a, shown in Figure 1, is detachably connected to the connector 15, and cable 2a is detachably connected to the data logger 2. The connector 15 is attached to the lower leg of the subject via an expandable annular band 15a.

[0024] The data logger 2 converts the analog measurement data output from each sensor on the sensor sheet 12 to digital data to generate digital measurement data indicating the detected compression force, and stores it in its internal memory in association with the location and time of the compression force detection. The data logger 2 is connected to the computer 3 for communication and transmits the toe compression force measurement data stored in its internal memory to the computer 3 based on control signals from the computer 3. The computer 3 stores the toe compression force measurement data received from the data logger 2 in its internal memory in association with the location and time of the compression force detection.

[0025] Computer 3 displays the toe compression force measurement data read from data logger 2 on the display based on the compression force detection location. Specifically, as shown in Figure 4, it displays an output image on the display in which the color of multiple cells distributed according to the position of each sensor changes according to the measured value of the toe compression force. The output image should preferably display the numerical value of the maximum compression force and a frame surrounding the location where the maximum compression force was detected. In Figure 4, the white area represents the area on the sensor sheet 12 where no load is detected, and the gray area outside of that represents the outer area of ​​the sensor sheet 12.

[0026] Returning to Figures 2 and 3, the belt 13 is an example of a support member that supports the substrate 11 in order to maintain contact between the subject's sole and the sensor sheet 12 when the measuring device 10 is attached to the subject's foot. Two belts 13 are attached to the measuring device 10 at positions separated front and back, and each belt 13 supports the substrate 11 so that the sensor sheet 12 does not separate from the sole of the foot when the foot is lifted off the floor. The front belt 13 is positioned to contact the top of the foot without interfering with the toes, and the rear belt 13 is positioned to contact the ankle. This allows the sole of the foot to make stable contact with the sensor sheet 12.

[0027] Each belt 13 is configured to be adjustable in length and at least one of its attachment points on the bottom surface to suit the size and shape of the foot. Each belt 13 may be configured to be adjustable in length using an adjuster, for example, or it may be attached to the bottom surface of the base plate 11 using hook-and-loop fasteners.

[0028] The heel cup 14 is located on the rear end side of the substrate 11 and positions the subject's toes relative to the sensor sheet 12 by contacting the subject's heel. The surface of the heel cup 14 that contacts the heel is curved in a concave shape to match the shape of the heel. The above describes the configuration of the measuring device 10.

[0029] Next, the procedure for measuring toe compression force performed by an examiner on a subject using the measurement system 1 according to the embodiment will be explained. It is assumed that a data logger 2 is connected to the measurement device 10 via cable 2a.

[0030] First, the subject is seated in a seated position, and the measuring device 10 is attached to the subject's feet. Specifically, the subject is first seated on a bed or chair, and asked to maintain a posture with their hip and knee joints flexed at 90°. Next, with the soles of the subject's feet in contact with the sensor sheet 12 and their heels in contact with the heel cup 14, the two belts 13 are tightened around the feet. After confirming that the measuring device 10 does not wobble relative to the subject's feet and that the soles of the feet do not leave the sensor sheet 12, the data logger 2 connected to the measuring device 10 is activated.

[0031] Next, the subject is instructed to perform an exercise in which they flex the MTP joint without flexing any other toe joints, such as the IP joint. In this step, the subject is instructed to maintain flexion of the MTP joint at maximum effort for 3 seconds. When each sensor on the sensor sheet 12 detects a toe compression force, each sensor transmits analog measurement data to the data logger 2. Each time the data logger 2 receives analog measurement data output from each sensor on the sensor sheet 12, it performs an A / D conversion to generate digital measurement data indicating the detected compression force, and stores it in its internal memory in association with the detection position and detection time of the compression force.

[0032] Flexion of the MTP joint should be performed separately for the big toe, lateral toe, and all toes. At this time, the examiner checks whether the subject is able to flex only the MTP joint. As shown in Figure 5(a), if only the MTP joint is flexed (IP extension condition), the subject's flexion exercise is considered successful. On the other hand, as shown in Figure 5(b), if both the MTP joint and the IP joint are flexed (IP flexion condition), or if inversion or eversion of the foot occurs, the subject's flexion exercise is considered unsuccessful, and the subject is instructed to flex only the MTP joint. Inversion of the foot is when the medial side of the sole of the foot moves away from the sensor sheet 12, and eversion is when the lateral side of the sole of the foot moves away from the sensor sheet 12. The subject's flexion exercise is terminated when the movement of flexing only the MTP joint has been performed a predetermined number of times.

[0033] Next, communication is established between the data logger 2 and the computer 3, and the data logger 2 reads the toe compression force measurement data from the data logger 2 to the computer 3. Then, the toe compression force measurement data is displayed on the computer 3's display, and the muscle strength of the subject's intrinsic foot muscles can be evaluated based on the measured values ​​of the toe compression force, especially the maximum compression force. The above is the procedure for the measurement method.

[0034] As described above, the measuring device 10 according to the embodiment comprises a substrate 11 with a flat upper surface, a sensor sheet 12 attached to the upper surface of the substrate 11 for measuring the distribution of compressive force from the subject's toes when the subject's toes rest on it, and a belt 13 attached to the substrate 11 for being worn on the subject's foot and supporting the substrate 11 so as to maintain contact between the sole of the subject's foot and the sensor sheet 12 when the subject's foot is lifted off the floor. Therefore, the compressive force from the toes can be measured while suppressing the influence of the subject's extrinsic foot muscles and body weight.

[0035] The present invention is not limited to the embodiments described above, and the following modifications are also possible.

[0036] (modified version) In the above embodiment, the lower surface of the substrate 11 was flat, but the present invention is not limited to this. Since the measurement using the measuring device 10 is not performed while the lower surface of the substrate 11 is stationary on the floor or while the subject is walking, the shape of the lower surface of the substrate 11 is arbitrary.

[0037] In the above embodiment, the substrate 11 was supported by a belt 13 to maintain contact between the sensor sheet 12 and the sole of the foot, but the present invention is not limited to this. For example, a stretchable mesh may be used as the support member.

[0038] In the above embodiment, the sensor sheet 12 was large enough to cover almost the entire surface of the substrate 11, but the present invention is not limited to this. For example, a sensor sheet 12 reduced in size to match the area where the toes make contact may be provided at the area where the toes make contact. In this case, the sensor sheet 12 may be made movable relative to the substrate 11 by adjusting the adhesive force of the sensor sheet 12 to the substrate 11. Alternatively, the heel cup 14 may be made movable in the front-rear direction of the substrate 11, and the position of the toes relative to the sensor sheet 12 may be adjusted according to the size of the subject's foot.

[0039] In the above embodiment, the load detection points of the sensor sheet 12 were distributed to measure the compressive force of individual toes, but the present invention is not limited to this. For example, the load detection points of the sensor sheet 12 may be distributed to measure the resultant force of the compressive forces of multiple toes simultaneously. For example, the load detection points of the sensor sheet 12 may be distributed to measure the compressive force of the big toe alone and the resultant force of the compressive forces of the second to fifth toes.

[0040] In the above embodiment, two belts 13 were attached to the substrate 11, but the present invention is not limited thereto. As long as the soles of the feet can be stably brought into contact with the sensor sheet 12, one belt 13 may be used, or three or more belts 13 may be attached to ensure that the soles of the feet can be stably brought into contact with the sensor sheet 12.

[0041] In the above embodiment, the length of the belt 13 was configured to be adjustable, but the present invention is not limited thereto. For example, the belt 13 may be made of an elastic material such as rubber or elastomer.

[0042] In the above embodiment, the substrate 11 and the heel cup 14 were separate components, but the present invention is not limited thereto. For example, the substrate 11 and the heel cup 14 may be integrated into a single unit.

[0043] In the above embodiment, a heel cup 14 was provided at the rear end of the substrate 11, but the present invention is not limited thereto. For example, if the foot can be positioned relative to the sensor sheet 12 by the belt 13, the heel cup 14 may be omitted, or a belt 13 positioned to contact the heel may be added instead of the heel cup 14.

[0044] In the above embodiment, the analog measurement data output from each sensor of the sensor sheet 12 was converted using an A / D converter by the data logger 2, but the present invention is not limited to this. For example, the sensor sheet 12 may be equipped with an A / D converter internally and output digital measurement data externally.

[0045] In the above embodiment, the digital measurement data stored in the data logger 2 was transmitted to the computer 3 and displayed on the computer 3's display, but the present invention is not limited to this. For example, the sensor sheet 12 and the computer 3 may be connected in a communicative manner without using the data logger 2, and the digital measurement data from the sensor sheet 12 may be stored in the computer 3. In this case, the computer 3 may be provided with the same or equivalent functions as the data logger 2. Alternatively, the measuring device 10 and the computer 3 may be integrated into a single device.

[0046] The embodiments described above are illustrative, and the present invention is not limited thereto. Various embodiments are possible without departing from the spirit of the invention as described in the claims. The components described in the embodiments and modifications can be freely combined. Furthermore, inventions equivalent to the invention described in the claims are also included in the present invention.

[0047] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples.

[0048] (Examples) In the embodiment, the compressive force of each toe was measured using the measuring device according to the embodiment, and the reliability of the measured values ​​was evaluated. Foot Scan (Nitta Corporation) was used as the sensor sheet for the measuring device. The subjects were six healthy adults (3 males and 3 females). The measurement position was a seated position on the edge of the bed, and measurements were performed on both the dominant and non-dominant feet. As shown in Figure 6, the ankle joint was measured in three positions: neutral, dorsiflexion at 15°, and plantarflexion at 45°. A goniometer was used to monitor the ankle joint angle.

[0049] The exercise task involved isometric flexion of the toe MTP joint, with maximum flexion held for 3 seconds. Measurements were taken three times per day, with a 7-10 day interval between the first and second measurements. For statistical analysis, the intraclass correlation coefficient (ICC) of the three toe compression forces was calculated. ICC is one indicator of the reliability of the test. The significance level was set at 5%.

[0050] As a result, we successfully measured the compressive force of each toe in all cases. On day 1, the ICC was 0.832 in the neutral ankle position, 0.857 in dorsiflexion, and 0.841 in plantarflexion. On day 2, the ICC was 0.904 in the neutral position, 0.831 in dorsiflexion, and 0.791 in plantarflexion. From the above, it can be seen that the measurement reliability of toe compressive force using the measuring device according to the embodiment is high at any ankle joint angle. [Explanation of symbols]

[0051] 1. Measurement System 2 Data Loggers 2a, 12a cable 3 Computers 10 Measuring device 11 circuit boards 12 Sensor Sheets 13 belts 14 Heel Cup 15 connectors 15a band

Claims

1. A substrate with a flat top surface, A sensor sheet is attached to the upper surface of the substrate and measures the distribution of compressive force applied by the subject's toes when the subject's toes are placed on it. A support member is attached to the substrate and is worn on the subject's foot, and supports the substrate so as to maintain a state in which the sole of the subject's foot is in contact with the sensor sheet when the subject's foot is lifted off the floor. A measuring device equipped with the following features.

2. The support member is a belt attached to the substrate so as to extend in the width direction above the substrate. The measuring device according to claim 1.

3. The measuring device further includes a heel cup provided on the rear end side of the substrate, which contacts the subject's heel to position the subject's foot relative to the substrate. The measuring device according to claim 1.

4. The sensor sheet is arranged vertically and horizontally and is equipped with multiple sensors that measure the compressive force applied by the subject's toes at each position. The measuring device according to claim 1.

5. A method for measuring the compression force of a subject's toes using a measuring device according to any one of claims 1 to 4, The process involves attaching the measuring device to the subject's feet so that the sensor sheet contacts the soles of the subject's feet while they are seated, A step of measuring the distribution of compressive force when the sensor sheet is compressed by flexing the MTP joint while the toe joints other than the MTP joint are not flexed, with the subject's foot lifted off the floor surface. A measurement method that includes [details omitted].

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