Dynamic monitoring system for patellar motion trajectory during knee flexion
By using a dynamic monitoring system for patellar movement trajectory during knee flexion, which incorporates matrix-distributed pressure sensors and a data processor worn at the knee joint, the problem of the inability to conduct portable dynamic monitoring of patellar movement trajectory in existing technologies has been solved, achieving low-cost and high-precision patellar movement trajectory monitoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BEIJING SPORT UNIV
- Filing Date
- 2025-07-08
- Publication Date
- 2026-06-12
AI Technical Summary
Existing technologies cannot achieve portable, dynamic monitoring of patellar movement trajectory during knee flexion, and are costly and dependent on other technologies, thus failing to meet daily monitoring needs.
A dynamic monitoring system for patellar movement trajectory during knee flexion was designed, comprising a flexible carrier and multiple pressure sensors. The pressure sensors are arranged in a matrix on the flexible carrier, and the data is calculated by a data processor to obtain the patellar movement trajectory.
It enables low-cost, portable patellar movement trajectory monitoring, improves monitoring accuracy and wearing comfort, and is suitable for daily use.
Smart Images
Figure CN224344927U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of sports biomechanics technology, specifically relating to a dynamic monitoring system for patellar movement trajectory during knee flexion. Background Technology
[0002] The patella slides up and down along the trochlear groove of the femur during knee flexion and extension. Abnormal patellar movement is an important biomechanical characteristic of various knee joint diseases (such as patellofemoral pain, patellar subluxation, and poor biomechanical recovery after anterior cruciate ligament surgery). Currently, the measurement of patellar movement mainly relies on MRI and biplane X-rays. These methods are not only costly and highly dependent on location and personnel, but also cannot provide dynamic, portable, daily monitoring. There is currently no wearable, portable solution that can achieve continuous monitoring of patellar movement.
[0003] During the squatting motion, the knee joint gradually flexes from near extension (0°) to 90°. As the force transmission structure of the knee extensor muscles, the patella exhibits the following typical movement characteristics during this process: (1) Vertical downward sliding: The patella slides downward along the trochlear groove of the femur, and the range of motion gradually increases with the increase of the knee flexion angle. (2) Slight medial and lateral deviation: Especially in those with muscle imbalance or structural abnormalities, the patella may deviate laterally or medially, producing an asymmetrical trajectory. (3) Rotation and tilting: The rotation or tilting of the patella around the vertical axis is more obvious when the knee flexion angle exceeds 60°.
[0004] During knee flexion and extension, the patella is located at the front of the knee joint and is the first bony landmark to come into contact with the anterior structures. Especially during knee flexion, the patella slides down along the trochlear groove of the femur, and its position, posture, and trajectory changes transmit clear pressure changes to the outside through the subcutaneous tissue. Utility Model Content
[0005] To address the aforementioned technical problems, the purpose of this utility model is to provide a simple and easy-to-wear dynamic monitoring system for patellar movement trajectory during knee flexion.
[0006] To achieve the above objectives, the technical solution of this utility model is as follows: A dynamic monitoring system for patellar movement trajectory during knee flexion includes a flexible carrier, a data processor, and multiple pressure sensors evenly distributed on one side of the flexible carrier. The flexible carrier is used to be attached to or bound to the knee joint, and the side of the flexible carrier with the pressure sensors is used to fit against the knee joint. All of the multiple pressure sensors are electrically connected to the data processor.
[0007] The beneficial effect of the above technical solution is that the flexible carrier with evenly distributed pressure sensors can be worn on the knee joint. When the knee joint moves from an upright position to a flexed position, multiple pressure sensors can monitor pressure data values. The data processor calculates the pressure data values monitored by multiple pressure sensors to obtain the patellar movement trajectory data at the knee joint.
[0008] In the above technical solution, the flexible carrier is rectangular, and the multiple pressure sensors are distributed in a matrix on one side of the flexible carrier.
[0009] The beneficial effect of the above technical solution is that it enables the pressure sensors to be distributed in a matrix on the corresponding side of the flexible carrier, so as to facilitate the calibration of the coordinates of each pressure sensor.
[0010] In the above technical solution, the spacing between two adjacent pressure sensors in the same row is less than or equal to 3 mm.
[0011] The beneficial effect of the above technical solution is that it makes the pressure sensors in the same row on the flexible carrier more densely distributed, which helps to improve the monitoring accuracy.
[0012] In the above technical solution, the distance between two adjacent pressure sensors in the same column is less than or equal to 3mm.
[0013] The beneficial effect of the above technical solution is that it makes the pressure sensors in the same row on the flexible carrier more densely distributed, which helps to improve the monitoring accuracy.
[0014] In the above technical solution, the spacing between two adjacent pressure sensors in the same row is the same as the spacing between two adjacent pressure sensors in the same column.
[0015] The beneficial effect of the above technical solution is that it makes the row and column spacing of the pressure sensors on the flexible carrier consistent, which is more conducive to the calibration of the coordinates of the pressure sensors.
[0016] The flexible carrier mentioned in the above technical solution is a silicone sheet, a latex sheet, or a rubber sheet.
[0017] The beneficial effect of the above technical solution is that it makes the flexible carrier more comfortable to wear.
[0018] The flexible carrier described in the above technical solution has straps on both sides.
[0019] The beneficial effect of the above technical solution is that the flexible carrier is worn in a binding manner at the knee joint when worn.
[0020] The above technical solution also includes a Bluetooth module disposed on the side of the flexible carrier away from the pressure sensor, the Bluetooth module being used to communicate with the data processor.
[0021] The beneficial effect of the above technical solution is that it enables the data monitored by the pressure sensor to be wirelessly transmitted to the data processor for data processing.
[0022] In the above technical solution, the flexible carrier on the side away from the pressure sensor is also provided with a power module and a control module, and the multiple pressure sensors, Bluetooth module and power module are all electrically connected to the control module.
[0023] The beneficial effect of the above technical solution is that the power module supplies power to the pressure sensor, while the control module integrates the monitoring data from multiple pressure sensors and transmits it to the data processor for processing via Bluetooth.
[0024] The data processor described in the above technical solution is a smartphone or a computer.
[0025] The advantages of the above technical solution are that it has a simple structure and good processing performance. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the dynamic monitoring system for patellar movement trajectory during knee flexion as described in Embodiment 1 of this utility model;
[0027] Figure 2 This is a schematic diagram of the flexible carrier facing away from the pressure sensor in Embodiment 1 of this utility model;
[0028] Figure 3 This is a schematic diagram of the wearable part being worn at the knee joint in Embodiment 1 of this utility model;
[0029] Figure 4 This is a schematic diagram of the patellar movement trajectory when the knee joint is bent in Embodiment 2 of this utility model.
[0030] In the diagram: 1 Flexible carrier; 2 Data processor; 3 Pressure sensor; 4 Straps; 5 Bluetooth module; 6 Power module; 7 Control module. Detailed Implementation
[0031] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are for illustrative purposes only and are not intended to limit the scope of this utility model. The utility model is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of this utility model will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this utility model.
[0032] Example 1
[0033] like Figure 1 and Figure 3 As shown, this embodiment provides a dynamic monitoring system for patellar movement trajectory during knee flexion, including a flexible carrier 1, a data processor 2, and multiple pressure sensors 3 evenly distributed on one side of the flexible carrier 1. The flexible carrier 1 is used to attach or bind to the knee joint, and the side of the flexible carrier 1 with the pressure sensors 3 is used to fit against the knee joint. The multiple pressure sensors 3 are electrically connected to the data processor 2. In this way, the flexible carrier with evenly distributed pressure sensors can be worn on the knee joint. When the knee joint moves from an upright state to a flexed state, the multiple pressure sensors can monitor pressure data values, and the data processor calculates the pressure data values monitored by the multiple pressure sensors to obtain patellar movement trajectory data at the knee joint.
[0034] In the above technical solution, the flexible carrier 1 is rectangular, and the multiple pressure sensors 3 are distributed in a matrix on one side of the flexible carrier 1. This makes the pressure sensors distributed in a matrix on the corresponding side of the flexible carrier, so as to facilitate the calibration of the coordinates of each pressure sensor.
[0035] In the above technical solution, the spacing between two adjacent pressure sensors 3 in the same row is less than or equal to 3mm (it can be 1mm, 2mm or 3mm), which makes the pressure sensors in the same row on the flexible carrier more densely distributed, which is beneficial to improving the monitoring accuracy.
[0036] In the above technical solution, the distance between two adjacent pressure sensors 3 in the same column is less than or equal to 3mm (it can be 1mm, 2mm or 3mm), which makes the pressure sensors in the same column on the flexible carrier more densely distributed, which is beneficial to improving the monitoring accuracy.
[0037] In the above technical solution, the spacing between two adjacent pressure sensors 3 in the same row is the same as the spacing between two adjacent pressure sensors 3 in the same column. This makes the row and column spacing of the pressure sensors on the flexible carrier consistent, which is more conducive to calibrating the coordinates of the pressure sensors.
[0038] The flexible carrier 1 described in the above technical solution is a silicone sheet, latex sheet, or rubber sheet, which makes the flexible carrier comfortable to wear.
[0039] The flexible carrier 1 described in the above technical solution is provided with straps 4 on both sides, so that the flexible carrier is worn at the knee joint in a binding manner when worn.
[0040] The above technical solution also includes a Bluetooth module 5 disposed on the side of the flexible carrier 1 away from the pressure sensor 3. The Bluetooth module 5 is used to communicate with the data processor 2, so that the data monitored by the pressure sensor can be wirelessly transmitted to the data processor for data processing.
[0041] The data processor 2 described in the above technical solution is a smartphone or computer, which has a simple structure and good processing performance.
[0042] like Figure 2 As shown, in this embodiment, a power module and a control module can also be provided on the side of the flexible carrier away from the pressure sensor. The power module can be a button battery box, and the control module can be a microcontroller chip, such as an STM32 series microcontroller chip. In this embodiment, multiple pressure sensors, Bluetooth modules, and power modules are electrically connected to the control module, and a power switch can be provided at the electrical connection point between the power module and the control module.
[0043] The patellar movement trajectory dynamic monitoring system during knee flexion described in this embodiment includes a wearable part and a data processing part. The wearable part includes a flexible carrier and pressure sensors, Bluetooth modules, power modules, and control modules mounted on it. The data processing part is a data processor (the data processor can install a corresponding APP program to process the data monitored by the pressure sensors).
[0044] Example 2
[0045] like Figure 4 As shown, this embodiment provides a monitoring method for the dynamic monitoring system of patellar movement trajectory during knee flexion as described above, including the following steps:
[0046] Step 1: Wear the flexible carrier 1 on the knee joint;
[0047] Step 2: Record the baseline pressure value of each pressure sensor 3 with the knee joint extended;
[0048] Step 3: Complete the knee flexion action and collect the knee flexion pressure value of each pressure sensor 3. Calculate the difference between the knee flexion pressure value and the baseline pressure value to obtain the pressure change value Pi.
[0049] Step 4: Calculate the overall pressure centroid coordinates (Xc, Yc) by weighting the position (xi, yi) of each pressure sensor 3 with the pressure change value Pi.
[0050] in,
[0051] The trajectory formed by the change of the centroid coordinates over time is the estimated curve of the relative motion trajectory of the patella. In this way, the trajectory change of the patella when the knee joint is flexed can be indirectly obtained by detecting the dynamic change data of pressure distribution through multiple pressure sensors on a flexible carrier (where i is the index number of a single sensing unit in the pressure sensing array, c itself is meaningless, Pi represents the pressure value detected by the sensing unit in real time, (xi,yi) are the position coordinates of the sensing unit in the plane coordinate system of the sensing array, and (Xc,Yc) represent the overall pressure centroid coordinates calculated based on the pressure weighted average of all sensing units).
[0052] This embodiment deeply integrates a flexible two-dimensional pressure sensor array with a patellar motion trajectory monitoring algorithm to form a novel, non-invasive, and low-cost trajectory reconstruction platform. Its technological innovation lies in:
[0053] The target is clearly focused on "patellar trajectory": unlike general knee joint motion monitoring devices, it focuses on "patellar trajectory reconstruction in the femoral trochlear groove". The target is clearly focused and the function addresses the clinical pain points of current sports injury mechanism assessment.
[0054] A high-density pressure sensor array covers the possible movement area of the patella: instead of point or ring layout, a large-area flexible matrix sensing area is used, which greatly improves the tolerance of patellar displacement and the accuracy of trajectory analysis.
[0055] Innovation in dynamic pressure center estimation and trajectory generation algorithm: By calculating the pressure center and combining it with dynamic correction of the knee flexion angle, a two-dimensional patellar movement trajectory with continuous time and accurate space is output.
[0056] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Those skilled in the art can readily implement this utility model based on the accompanying drawings and the above description. However, any modifications, alterations, or equivalent variations made by those skilled in the art without departing from the scope of the utility model's technical solution, utilizing the disclosed technical content, are considered equivalent embodiments of this utility model. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of this utility model are still within the protection scope of this utility model's technical solution.
Claims
1. A dynamic monitoring system for patellar movement trajectory during knee flexion, characterized in that, The device includes a flexible carrier (1), a data processor (2), and multiple pressure sensors (3) evenly distributed on one side of the flexible carrier (1). The flexible carrier (1) is used to attach or bind to the knee joint, and the side of the flexible carrier (1) with the pressure sensors (3) is used to fit against the knee joint. The multiple pressure sensors (3) are electrically connected to the data processor (2).
2. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 1, characterized in that, The flexible carrier (1) is rectangular, and multiple pressure sensors (3) are distributed in a matrix on one side of the flexible carrier (1).
3. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 2, characterized in that, The spacing between two adjacent pressure sensors (3) in the same row is less than or equal to 3 mm.
4. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 2, characterized in that, The spacing between two adjacent pressure sensors (3) in the same column is less than or equal to 3 mm.
5. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 2, characterized in that, The spacing between two adjacent pressure sensors (3) in the same row is the same as the spacing between two adjacent pressure sensors (3) in the same column.
6. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 1, characterized in that, The flexible carrier (1) is a silicone sheet, a latex sheet, or a rubber sheet.
7. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 1, characterized in that, The flexible carrier (1) is provided with straps (4) on both sides.
8. The dynamic monitoring system for patellar movement trajectory during knee flexion according to any one of claims 1-7, characterized in that, It also includes a Bluetooth module (5) disposed on the side of the flexible carrier (1) away from the pressure sensor (3), the Bluetooth module (5) being used to communicate with the data processor (2).
9. The dynamic monitoring system for patellar movement trajectory during knee flexion according to claim 8, characterized in that, The flexible carrier (1) is also provided with a power module (6) and a control module (7) on the side away from the pressure sensor (3), and multiple pressure sensors (3), Bluetooth modules (5) and power modules (6) are electrically connected to the control module (7).
10. The dynamic monitoring system for patellar movement trajectory during knee flexion according to any one of claims 1-7, characterized in that, The data processor (2) is a smartphone or a computer.