DE102021111917A1 - Device and method for determining at least one mobility parameter of a living being, and use of an image acquisition device and a determination device - Google Patents

Abstract

A device (10) for determining a mobility parameter of a living being (12) comprises an image capturing device (14) which is designed and set up to capture at least one pose of the living being (12), and a determining device (1) connected to the image capturing device (14). 18) which is designed and set up to determine a plurality of prominent skeletal points of the skeletal anatomy of the living being (12) from the recorded pose, the determination device (18) also being designed and set up to determine at least a first pair of prominent skeletal points define and from this to determine at least one mobility parameter, wherein the mobility parameter comprises a variable that characterizes an angle that is formed between a first connecting straight line that is spanned by the first pair of skeletal points, and a straight reference line. It is proposed that the determination device (18) is also designed and set up to determine a maximum value and/or a minimum value of the angle, an angular velocity and/or a course of the angular velocity from a plurality of poses and angles that are detected in immediate succession.

Description

The invention relates to a device and a method for determining at least one mobility parameter of a living being, as well as the use of an image acquisition device and a determination device.

The success of an orthopedic treatment in a living being is fundamentally defined, in addition to the painful movement, by the mobility of the treated area made possible by the treatment or the course of mobility. For example, after an operation on a human shoulder joint, the success of the operation can be defined by the mobility of the upper arm either relative to a starting position or relative to a reference line or relative to the other upper arm. This mobility can change in the course of treatment or with an increasing time interval from an operation, until maximum mobility on the one hand and “fluent” and pain-free mobility on the other are achieved. Using the example of the upper arm, mobility can be described by a maximum angle of the upper arm relative to the vertical up to which the operated person can lift the upper arm (without pain). This angle is often simply estimated, sometimes also measured using a mechanical angle gauge. The same applies to other orthopedic treatments or interventions, for example on the elbow joint, hip joint or knee joint.

Also known is the so-called “neutral zero method”, which is common in medicine and represents a standardized orthopedic evaluation and documentation index for the mobility of joints. The angle of the limb to the vertical is usually used as a reference here, or a starting position is used, which is defined for a human as follows: the human stands upright, the arms are relaxed hanging down, the thumbs pointing forward and the feet pointing stand parallel.

However, measuring the angle using a mechanical angle gauge is relatively complex and imprecise. Whether the angle is only generated at the joint on which the extremity is mounted, or whether other influences also play a role, has not been taken into account or only to a limited extent. Or, in other words: It is not taken into account which joint makes which contribution to the movement of the limb. The result of a measurement can also differ depending on how the measurement is taken, for example from doctor to doctor or from physiotherapist to physiotherapist. The previously used mechanical angle gauge thus has multiple potential sources of error.

It is also known to use an image capture device, for example a CCD camera, to capture a pose of a living being, for example a human being, and to use a computer-based determination device to determine a plurality of distinctive points of the skeletal anatomy of the living being from the captured pose. This is used, for example, in the automotive sector to control devices using gestures, and in video games to capture a player's interaction.

Such an image acquisition device is known, for example, under the trade name “Kinect” from Microsoft, which is hardware for controlling video game consoles. The open source project "openni.org" developed software for this purpose that evaluates the data from the Kinect depth camera in real time and, for example, recognizes/isolates people in front of the camera as such. Furthermore, a human "standard skeleton" with corresponding skeletal points is projected into recognized/isolated persons, and the positions of the extremities of this skeleton at the skeletal points are tracked to the isolated person in the best possible way and in real time, see for example https://de.wikipedia.org /wiki/Kinect.

Furthermore, the international patent publication discloses WO 2013/087084 A1 to use an anatomical topology, i.e. a model of the skeletal anatomy, which consists of a plurality of nodes that are associated with distinctive human body points. Such a prominent point can be a head, a shoulder, an elbow, a hand, etc., for example.

In Thieme E-Journals - journal for orthopedics and trauma surgery, Georg Thieme Verlag KG, July 10th, 2019, the article "Movement analysis in orthopedics and trauma surgery - measuring systems and their clinical application" by Konrad Oppelt, Aidan Hogan, Felix Stief, Paul Alfred Grützner, Ursula Trinler published.

On December 11, 2018, an article by S. Lutherdt et al. published, which deals with motion analysis using the Microsoft Kinect.

A publication by Stepan Obdrzalek et al. available, which describes the use of Microsoft Kinect technology to determine the pose of elderly people.

Finally, it has also been known for a long time to attach sensors and/or markings to the extremities of a living being, which can be observed by appropriate automated detection devices and whose position changes can be detected in this way.

It is the object of the present invention to create a simple device and a method which enable a precise and inexpensive measurement and evaluation of at least one mobility parameter of a living being.

This object is achieved by a device and a method having the features of the independent claims. Advantageous developments are specified in the dependent claims.

Thanks to the invention, it is possible, without using inaccurate and bulky angle gauges and without having to use special sensors or markings, and with only a single detection device or two or at most three detection devices (cameras) that detect the living being from one direction in space or two or three observe Cartesian spatial directions to record at least one mobility parameter of a living being precisely and quickly. Sources of error are reduced and an internal validity of the values is always guaranteed with the same device (minimization of the examiner bias). For example, in the case of a person it is possible—within certain limits—to determine at least one mobility parameter without the person having to completely remove their clothing. The device according to the invention and the method according to the invention can be used in one application as a diagnostic examination tool, for example in an orthopedic practice, in order to measure mobility and diagnose problems or simply to record an actual state, accordingly also in the course of the treatment success objectify. The values obtained describe the maximum efficiency and, plotted over time, enable problem areas to be identified. In addition to the well-known subjective dimensions, both serve to monitor the progress after, for example, orthopedic operations and conservative therapies.

The method according to the invention can possibly even redefine the norm of mobility. This is especially the case if it is used extensively and frequently. In practice, it has been shown that the average human population tends to be below the maximum values. Thus, by means of the device according to the invention and by means of the method according to the invention, the question as to which values are normal and which values must be regarded as pathological can be answered with greater reliability than before.

The invention also creates the possibility of specifying certain standard values or references in the first place, since the invention enables analyzes that were previously not possible. For example, the invention can be used to analyze which part of the movement comes from joint X and which part of the movement comes from joint Y. Completely new quality parameters are thus made possible with the invention.

Another application is, for example, sports, since the invention makes it possible to identify and/or analyze and/or optimize specific movements for certain types of sports and, for example, to make training results quantifiable. As will be explained in more detail below, a more objective quality assurance of operation results is also made possible, for example, by a “before and after” comparison. Furthermore, the mobility parameter achieved by the intervention can be determined intraoperatively, ie already during an intervention, for example while the patient is still under anesthesia, which makes it possible to objectify the surgical result.

Finally, the measurement itself of the mobility parameter is also objectified, allowing a better separation between "subjective" and "objective" problems. Through objectification the measurement of the mobility parameter, measurements made by different people are also made comparable, since the result of the measurement no longer depends on the way in which the measurement was made. So-called “physician-specific” influences can thus be eliminated. For example, measurements taken by the orthopedist and by the physiotherapist become comparable. The implementation of treatments and the preparation of surgical interventions are also made easier by the invention, since the properties of the joint to be treated or operated on can be determined much more precisely and easily with the invention.

Specifically, this is achieved by a device for determining at least one mobility parameter of a living being, which includes an image acquisition device. Such an image capturing device can be designed, for example, as a 3D camera, for example a camera of the “Kinect II” type. Current smartphone cameras are also possible, for example the camera of the iPhone 12. Although a person is primarily a possible living being, an animal, for example a dog or a horse, etc., is also conceivable. Such an image capturing device is designed for this and set up to capture at least one pose of the living being, namely without the projection of auxiliary lines by means of a projector or the application of markers at certain points of the body, only using known image recognition techniques. In the present case, a pose is understood to mean a position or posture of the body or a part of the body of the living being. For example, if the living being moves an extremity, this results in a plurality or a sequence of poses that follow one another in direct time.

An automatic determination device is connected in terms of data technology to the image acquisition device. The connection can include a wired interface, but also an interface that works wirelessly. The automatic determination device is designed and set up to determine a plurality of distinctive skeletal points of the skeletal anatomy of the living being from the recorded pose.

In this respect, the determination device is usually one or more computers with at least one microprocessor, at least one memory and program code. The fact that according to the invention "a plurality of prominent skeletal points of a skeletal anatomy of the living being is determined from the recorded pose" means in the present case that, similar to the prior art, for example a "standard skeleton" or "skeleton model" of the living being under consideration with corresponding skeletal points in one of the automatic detection device recognized or isolated living being is projected into it, so that neither a projection of auxiliary lines by means of a projector or the application of markers at certain points of the body of the living being is necessary.

Distinctive skeletal points within the meaning of the present invention can correspond, for example, to locations where a joint is located on which an extremity is mounted, or where an extremity ends, or through which the course of an anatomical skeletal unit (e.g. spine) is defined. Typical distinctive skeletal points within the meaning of the present invention are in a person and also in numerous animals, for example, a central area of a spine, an area of the spine in the area of the jugulum and in the area of the hip or pelvis, a shoulder joint, an elbow joint, a wrist , a thumb tip, a hand tip, a hip joint, a knee joint, an ankle joint, a toe joint, a neck and a head. In principle, however, other prominent skeletal points are also conceivable, for example toe and/or finger joints.

According to the invention, the determination device is also designed and set up to define at least a first pair of prominent skeleton points. The skeletal points of such a pair are preferably adjacent skeletal points, for example shoulder joint/elbow joint or shoulder joint/jugulum, etc., since such adjacent skeletal points define the corresponding extremities of the living being very well. For example, the shoulder joint/elbow joint skeletal point pair defines an upper arm and the elbow joint/wrist skeletal point pair defines a forearm.

Finally, the determination device is also designed and set up according to the invention to determine a mobility parameter in the form of a variable that characterizes an angle that is formed between a first connecting straight line that is spanned by the first pair of skeleton points and a straight reference line. This is possible, for example, by appropriate trigonometric arithmetic operations, in which the connecting straight line passing through the two skeletal points is determined from the coordinates of the two skeletal points of the skeletal point pair. By means of appropriate trigonometric arithmetic operations, it is then possible to determine the angle between this connecting straight line and another straight line which forms the reference line.

In the simplest case, the reference line is the vertical. Another possible mobility parameter, as will be explained below, is a movement speed and/or an acceleration (both positive and negative) of the extremity or body part, specifically both translationally and rotationally. A position of a skeletal point relative to another skeletal point can also be a mobility parameter to be determined.

With the mobility parameter mentioned in the form of an angle, it is conceivable that the reference line can be freely selected by the user of the device, for example an examining doctor, by making a corresponding entry on the device. It is conceivable, for example, that a person will be placed in the "neutral position" or neutral position according to the "neutral zero method" at the beginning of the examination, and that this starting position will then define the reference position in which the angles of the extremities being examined are defined are zero relative to the reference line. This definition can be done, for example, by the user of the device resetting the angle to zero by means of a corresponding input when the person to be examined has assumed the “neutral position”.

It should be noted at this point that in a simplified technical realization of the device according to the invention and the method according to the invention, the pose is only recorded in a plane that is orthogonal to a viewing direction through the image recording device, as a result of which the skeletal points are only present in this two-dimensional plane . Accordingly, movements out of this plane are not taken into account. In practice, the image capturing device is directed at a human being, for example, frontally from the front or from behind, or from the side. If a three-dimensional view is nevertheless desired, it is also possible to work with two image capturing devices which are arranged at an angle of 90° to one another, for example, so that the poses of the living being are captured simultaneously in two mutually orthogonal planes. Alternatively, it is also possible to work with an image acquisition device that acquires the pose(s) in a three-dimensional space.

The invention also includes the determination device being designed and set up to determine a maximum value of the angle and/or a minimum value of the angle and/or a speed of the change in the angle (angular speed) and/or or to determine a course of the angular velocity. In this development of the invention, the movement of at least the region of interest of the skeletal anatomy of the living being is recorded over a specific period of time and/or a specific range of movement, in particular angular range, and the maximum or minimum value reached during this movement is then determined. A mean value can also be formed from a plurality of movement sequences. Thus, not only a static, but also at least one dynamic mobility parameter can be determined, whereby the diagnostics are further improved. It goes without saying that the corresponding pose can be repeatedly assumed by the living being in order to verify the maximum values or minimum values, and that a mean value can then be determined from the maximum values or minimum values determined for each pose. However, it goes without saying that the invention also has advantages with the detection of a stationary angle value, for example when analyzing a stiff extremity.

The determination device can therefore be designed and set up to determine a movement profile, in particular a profile of the movement speed, and further in particular a profile of the angular velocity from a plurality of directly consecutive poses. In this case, a “course” can be understood both, for example, as a course of the speed of the movement over time and a course of the speed of the movement over the current angle. In this way, it can be found out, for example, whether the movement is fluid or whether it stops at certain points. This also allows conclusions to be drawn about orthopedic problems and/or enables targeted treatment to improve the fluidity of movement.

In a further development, it is proposed that the determination device be designed and set up to define a second pair of prominent skeleton points and to use a second connecting straight line, which is spanned by the second skeleton point pair, as a reference line for the angle. Thus, for example, in the context of orthopedic care and / or orthopedic Aftercare, the mobility of an isolated joint can be recorded much more precisely than before and thus diagnosed, since the movements of other joints and thus their influence on the joint to be examined and the movement of an extremity around this joint can be taken into account in a simple manner. The invention thus enables a holistic view of the “chain of movements” instead of the previous isolated view of the isolated extremity or the isolated joint. This also allows causes to be identified that lie far away from the extremity or the joint actually being considered.

A typical example of this is the shoulder joint: in the neutral-zero method that has been used to date, its functionality is described by the mobility of the upper arm relative to a hanging starting position (i.e. approximately vertical). However, the actual position of the upper arm relative to the vertical can also be influenced, for example, by raising the shoulder joint and also, optionally also independently, the shoulder blade and/or an inclined position of the longitudinal body axis. This can also be detected and taken into account by the invention. The development according to the invention can thus take into account the entire interaction of the skeletal anatomy, as a result of which completely new diagnostic approaches are possible and previously necessary additional diagnostic methods can be dispensed with. This means that considerable costs can also be saved in the orthopedic practice.

This applies all the more if the first pair of skeleton points and the second pair of skeleton points have a common skeleton point. In this case, the invention makes it possible to determine a true "net mobility" of a limb relative to a joint to which the limb is attached. However, it is also possible for the so-called "opposite side" to be selected as the reference line, ie for example the respective other arm or the respective other leg, insofar as these can be defined by the second pair of prominent skeletal points.

In a development of this, it is proposed that the device includes a memory device that is designed and set up to store the maximum value or the minimum value. In this way, it is possible to compare maximum values or minimum values recorded or determined at different points in time and in this way, for example, to recognize the progress of the disease or the progress of healing. It is also possible in this way to record and store the maximum and minimum values in healthy people and to determine statistical standard variables from them. These can then be used again for diagnostics, i.e. for recognizing deficits. Since, thanks to the invention, it is possible to very precisely determine the contribution of the individual joints to the mobility or movement of an extremity, the standard variables obtained in this way are significantly more meaningful than before.

In a development of this, it is proposed that it includes an evaluation device that is designed and set up to evaluate a time profile of maximum values or minimum values and/or angular velocities and/or profiles of the angular velocities stored at different points in time. There is therefore an automated evaluation of the course over time. This evaluation can include, for example, determining a gradient, that is to say a speed at which the maximum values or minimum values and/or angular speeds and/or curves of the angular speed change over a specific period of time. This speed can, for example, be compared with empirical target values or standard values, which automatically allows conclusions to be drawn about the quality of the course of the disease or the course of healing or, for example in sports, the course of training. It goes without saying that the evaluation device, analogous to the determination device, can be implemented by program code that is stored in a memory and runs on a microprocessor of a computer.

In a further development of this, it is proposed that the evaluation device be designed and set up to determine a quality parameter from the time profile of the maximum values or minimum values and/or angular velocities and/or profiles of the angular velocities, which characterizes a treatment and/or training success . This enables a reproducible and objective measurement of a treatment and/or training success. In the case of a surgical intervention, this applies in particular when the maximum values or minimum values are also available from a point in time relatively shortly before a surgical intervention.

In a further development of this, it is proposed that it includes a communication device that is designed and set up to transmit the maximum value or the minimum value and/or the angular velocities and/or the curves of the angular velocities or, if present, the result the evaluation of the time profile of the maximum values or the minimum values or, if present, the quality parameter to an external processing device arranged remotely from the device. Such an external processing device arranged remotely from the device can be present at a health insurance company, for example, or it can be a mobile terminal device, for example a smartphone or a tablet PC, or a normal PC of the person examined himself. In this way, it is possible, for example, for an external quality office, a study facility, a health insurance company, etc., to qualitatively evaluate different surgeons and/or surgical methods. Furthermore, it can be made possible in this way, for example, for a training person to analyze the movements performed without having to be present while the movements are being performed. Alternatively or additionally, this further training enables the person examined to view the result, for example to promote motivation, or to carry out further evaluations, for example in connection with health apps that are common today. The values are preferably transmitted anonymously, in accordance with data protection regulations.

In a further development, it is proposed that the device includes an output device, in particular a monitor for numerical and graphic representation, which is designed and set up to graphically display at least the first connecting line and preferably also the reference line and its relative position in real time and/or the size , which characterizes the angle and/or the angular velocity and/or the course of the angular velocity, preferably in real time, numerically and/or graphically. This makes it possible to check during the examination whether the skeletal anatomy has really been determined correctly. A visual representation of motion also enables a physician to immediately visually identify a potential problem. In addition, it allows the potential problem to be demonstrated to the patient in situ to encourage patient reflection and understanding. Alternatively or additionally, the output device can also be used to show a patient a video or an animation that shows the movement or movements that the patient should perform. This allows a specific movement to be trained. Optionally, the recorded movement could then be displayed simultaneously with the specified movement, so that the patient and/or the practitioner can recognize differences between the specified movement and the movement actually performed.

In one development, it is proposed that the determination device be designed and set up to determine a variable that characterizes a distance between two skeleton points. This determination can take place, for example, using standard trigonometric relationships from the determined positions of the skeleton points. When analyzing the mobility of the living being, this makes it possible to take into account not only the determined mobility parameter, but also, for example, the lever arm provided by the length of the extremity. This can be a useful tool, for example in sports. In golf, for example, it could very easily be found out in this way which club length brings about or enables the most harmonious movement.

In a further development, it is proposed that the determination device be designed and set up to output, store and/or store a boundary condition linked directly or indirectly to the pose together with the determined maximum value and/or minimum value of the angle, the angular velocity and/or the course of the angular velocity. or to process. Such an indirect boundary condition can be an environmental parameter, for example an ambient temperature and/or humidity and/or a time, and/or a variable associated with the living being, for example an age and/or a weight and/or a size. Such a boundary condition linked directly to the pose can be, for example, a type and/or magnitude of a load that acts on a limb during the pose. For example, a person can hold a dumbbell in their hand or put weight on the limb with a so-called "Terraband". These boundary conditions (for example weight or force) can be transmitted to the determination device by the user of the device, for example by means of an input device.

• 1 eine schematische Darstellung einer Vorrichtung zur Ermittlung mindestens eines Mobilitätsparameters eines Lebewesens in Form einer Person in einem Blockschaltbild;
• 2 eine von der Vorrichtung von 1 verwendbare mögliche Skelettanatomie mit markanten Skelettpunkten der Person von 1;
• 3a-3g schematische Darstellungen von unterschiedlichen Posen einer Person und der hierauf projizierten Skelettpunkte der Skelettanatomie;
• 4 ein Diagramm, in dem ein Winkel mehrerer Verbindungsgeraden, die durch benachbarte Skelettpunktepaare aufgespannt werden, gegenüber verschiedenen Bezugslinien über der Zeit aufgetragen ist;
• 5a-5d ein möglicher Verlauf der Position der Skelettpunkte im Bereich der Schulter einer Person beim Anheben des Oberarms;
• 6 ein Flussdiagramm eines Verfahrens zur Ermittlung mindestens eines Mobilitätsparameters eines Lebewesens mit der Vorrichtung von 1;
• 7 ein Diagramm, in dem eine Winkelgeschwindigkeit über der Zeit aufgetragen ist; und
• 8 ein Diagramm, in dem eine Winkelgeschwindigkeit über dem Winkel aufgetragen ist.

The invention is explained below with reference to the attached drawing. Show in the drawing:

• 1 a schematic representation of a device for determining at least one mobility parameter of a living being in the form of a person in a block diagram;
• 2 one from the device of 1 usable possible skeletal anatomy with prominent skeletal points of person from 1 ;
• 3a-3g schematic representations of different poses of a person and the skeletal points of the skeletal anatomy projected thereon;
• 4 a diagram in which an angle of several connecting lines, which are spanned by adjacent pairs of skeletal points, is plotted against various reference lines over time;
• 5a-5d a possible course of the position of the skeletal points in the area of the shoulder of a person when raising the upper arm;
• 6 a flowchart of a method for determining at least one mobility parameter of a living being with the device from 1 ;
• 7 a diagram in which an angular velocity is plotted against time; and
• 8th a diagram in which angular velocity is plotted against angle.

A device for determining at least one mobility parameter of a living being contributes in 1 overall reference numeral 10. In the present example, the living being is a person 12. In other non-illustrated embodiments, it could also be an animal, for example a dog or a horse.

The device 10 includes an image capturing device 14 in the present example in the form of a 3D camera, which is directed at the person 12 along an observation direction 16 . Device 10 also includes a determination device 18 connected to the image acquisition device. In the present example, this is implemented by a computer with at least one microprocessor 20 and a memory 22.

Stored in memory 22 is program code, which is used to implement various functions of determination device 18 and thus of device 10 that will be explained in more detail below when this program code is executed by microprocessor 20 . In this way, the determination device and ultimately the device is designed and set up to implement the said functions.

The device 10 also includes an output device 24, in the present example in the form of a monitor, and an input device 26, in the present example in the form of a keyboard and/or a computer mouse. In an embodiment that is not shown, the input device can also include a microphone for inputting speech and/or a camera for detecting gestures. The device 10 can be connected to an external processing device 30 arranged at a distance from the device 10 via an interface 28 , symbolized in the present case by an arrow. The interface 28 can be a wired and/or a wireless interface.

The determination device 18 is designed and set up to determine a plurality of prominent skeletal points of the skeletal anatomy of the person 12 from the pose of the person 12 captured by the image capture device 14 . In the present case, a pose is understood to mean a position or attitude of the body of the person 12 . If the person 12 moves an extremity, for example, then this results in a plurality of poses that follow one another in direct time.

To determine the distinctive skeletal points of the skeletal anatomy of the person 12, as is known from the prior art, the determination device 18 projects a standardized human skeletal anatomy with corresponding skeletal points into the person 12 identified or isolated by the determination device 18 and the image acquisition device 14 . Such a standardized human skeletal anatomy is exemplified in 2 shown and denoted overall by the reference numeral 32 there. The prominent skeletal points of skeletal anatomy 32 are in 2 denoted by the indices ay. The assignment to the medical anatomical skeletal points corresponds, again only as an example, to the following table: index skeletal point index skeletal point a head m right hand b neck n Right hand tip c jugular O right thumb i.e right shoulder p mid spine e Right Elbow q pool f right wrist right Right hip joint G right hand s Right knee joint H Right hand tip t Right ankle i right thumb and Right toe j left shoulder v Left hip joint k Left Elbow w Left knee joint l left wrist x Left ankle y Left toe

In the 3a-3g an upper body of the person 12 is shown in different poses merely for exemplary explanation. It goes without saying that the poses shown are only a few selected exemplary poses and basically an infinite number of other poses and intermediate poses are conceivable. Poses from other perspectives are also conceivable, for example from the side or from behind. Likewise in these 3a-3g some of the skeleton points are shown, as well as the straight connecting lines that connect adjacent skeleton points with one another, as determined by the determination device 18 for the detected poses.

In the pose of 3a the person 12 stands straight and upright facing the front with arms hanging down. In the pose of 3b the person 12 stands straight and upright with arms widely extended. In the pose of 3c the person stands straight and upright with arms hanging down and shoulders raised. In the pose of 3d Person 12 stands straight and upright with arms outstretched and slightly raised. In the pose of 3e the person stands straight and upright with the right arm hanging down and slightly spread, while the left upper arm is raised horizontally and the left forearm is stretched vertically upwards. In the pose of 3f the person stands straight and upright with arms not fully extended, right hand, palm facing forward. In the 3g the person 12 tilts the upper body to the left (as viewed from the person) with the arms spread out. Now will open 4 referenced. The right area of the upper body of the person 12 is drawn there with the corresponding skeletal points cf (jugulum, right shoulder, right elbow, right wrist) and p (middle of the spine).

The determination device 18 is also set up and designed to define pairs of prominent skeleton points. In the case of the skeletal anatomy 32, skeletal points that are adjacent to one another are preferably defined, and a connecting straight line is then determined by the determination device 18, which connects the skeletal points of a respective pair of skeletal points to one another.

Corresponding connecting lines 34-40 between the adjacent skeleton points determined by the determination device 18 are shown in FIG 4 also drawn. A connecting straight line 34 between the skeletal points c and p (corresponding to the spinal column or body longitudinal axis) is drawn in broken lines. A connecting straight line 36 between the skeletal points c and d (jugulum-shoulder axis) is drawn in dotted lines. A connecting straight line 38 between the skeletal points d and e (upper arm) is drawn as a solid line. A connecting straight line 40 between the skeletal points e and f (forearm) is drawn in dashed lines.

The determination device 18 is also set up and designed to determine a mobility parameter, in this case a variable that characterizes an angle α, which is formed between a connecting straight line that is spanned by a pair of skeleton points and a reference line. It is assumed here by way of example that the reference line for the connecting straight line 34 (longitudinal body axis) and the connecting straight line 38 (upper arm) is the vertical, and that the reference line for the connecting straight line 40 (lower arm) is the connecting straight line 38 (upper arm). It is fundamentally conceivable that for each extremity of the body of the person 12 or for each straight line connecting adjacent skeletal points of the skeletal anatomy 32, the user of the device 10 can select the desired reference line, for example by making a corresponding entry on the Input device 26. In 4 the skeleton points e and f are also referred to as the first pair of skeleton points 41, and the skeleton points d and e as the second pair of skeleton points 43.

In 4 A diagram is also plotted in which the angles α between the longitudinal axis of the body (connecting line 34) and the upper arm (connecting line 38) relative to the vertical and of the forearm (connecting line 40) relative to the upper arm (connecting line 38) are plotted automatically by determination device 18 over the Time t are plotted when the person 12 performs different movements in a chronological sequence, which lead to chronologically successive poses. The curve for the longitudinal axis 34 of the body is shown in broken lines, the curve for the upper arm 38 in solid lines and the curve for the lower arm 40 in broken lines.

You can tell 4 for example, that the person 12 is continuously very slightly crooked, because the angle α between the longitudinal axis of the body and the vertical is continuously slightly smaller than zero. You can also tell 4 , that when person 12 raises their right arm from the hanging position (solid line, angle α approximately 0, corresponding approximately to the pose in 3a ) and extends it horizontally (angle α approximately 90°), the right forearm also makes a small movement relative to the right upper arm (dashed line; similar to the pose in 3b ).

Finally, the maximum values of the angle α can also be seen in the form of the “peaks” of the solid line. From the gradient from the zero position to a (possibly also plateau-like) peak, the angular velocity until the maximum value is reached, and from the gradient from the peak to the zero position, the angular velocity until the zero position is reached. The course of the angular velocity results in turn from the course of the gradient. The maximum value of the angle of the last pose taken can be displayed on the output device 24 as a current numerical value. Furthermore, an average value of the maximum values recorded in succession can be displayed on the output device 24 . The current angular velocity can also be displayed on the output device 24 as a numerical value, as well as an average value of the angular velocities recorded in succession.

As already explained above, the device 10 also includes an output device 24, for example in the form of a monitor. The person 12 can be displayed on this, for example in the form of an avatar or a real image together with the skeletal anatomy 32 in real time in the current pose, together with the numerical values of the angles determined by the determination device 18 relative to a predefined reference line on the subject of interest Skeletal points, for example in the exemplary embodiment shown here at the shoulder joint (skeletal point d), at the elbow joint (skeletal point e), at the wrist (skeletal point f) and in the middle of the spine (skeletal point p). The output device 24 can also be used to specify to the patient, for example via a film, which movement he should carry out. Thereafter, for example, a timer could be displayed on the output device 24 that counts down while the patient performs the movement. This could, for example, also enable self-training without the presence of a doctor, for example.

In the 4 The type of diagram shown as an example can also be used when training athletes. For certain motion sequences in certain types of sports, there are typical curves that can be analyzed and used to optimize the motion sequences. For example, typical curves that have been determined for top athletes can be compared with the curves of other athletes and specific training recommendations can be generated from this.

The device 10 is particularly useful for orthopedic diagnosis, as now referred to in FIG 5a-5d will be explained. It is shown there by way of example how it is possible with the device 10 to determine the actual “net mobility”, for example of the shoulder joint (above skeletal point d).

In 5a the starting position of the person 12 is shown with the upper arm hanging down (connecting line 38). In 5b the person 12 has the upper arm raised to an approximately horizontal position. In 5c the person 12 tried to raise the upper arm again. However, since a relative movement of the upper arm in the shoulder joint itself was no longer possible, the person 12 simply lifted the shoulder joint (change in the position of the connecting straight line 36).

It can be seen that the angle between the two connecting lines 38 and 36 between the 5b and 5c stayed the same. In 5d the person 12 tried to raise the upper arm again. However, since a stronger relative movement of the upper arm in the shoulder joint was no longer possible, she simply tilted her upper body to the side (oblique position of the connecting line 34). Again, you can see that the angle between the two connecting lines 38 and 36 between the 5d and 5c stayed the same. The "net mobility" of the upper arm is therefore approximately 90°.

Now will open again 1 referenced. The device 10 comprises a sub-device 42 in the determination device 18, which is designed and set up to determine a maximum value and/or a minimum value of the angle from a plurality of directly consecutive poses of the person 12 and determined angles. The determined maximum values or minimum values can then be stored in memory 22 .

The device 10 also includes a further sub-device 44 which forms an evaluation device. This is designed and set up to evaluate a time profile of maximum values or minimum values of the determined angles stored in memory 22 at different points in time. For example, a speed (gradient) can be determined, with which the determined maximum values or minimum values change when examinations of the person 12 are carried out at time intervals.

For example, the evaluation device 44 can be designed and set up to determine a quality parameter from the time profile of the maximum values or the minimum values, which characterizes the success of the operation. For example, the speed determined above or the gradient determined above can be compared with a standard value. If the maximum values or the minimum values increase very quickly, this means that the mobility of the corresponding limb is rapidly improving, so that the corresponding quality parameter would indicate a good surgical success. On the other hand, if the maximum or minimum values increase only very slowly, this would be a sign of a rather poor success of the operation.

• Das Verfahren beginnt in einem Startblock 46. In einem Funktionsblock 48 wird eine Pose eines Lebewesens, vorliegend beispielhaft der Person 12, mittels der Bilderfassungseinrichtung 14 erfasst. In einem Funktionsblock 50 wird auf der Basis der von der Bilderfassungseinrichtung 14 gelieferten Signale von der Ermittlungseinrichtung 18 eine Mehrzahl von markanten Skelettpunkten der Skelettanatomie der Person 12 aus der erfassten Pose ermittelt. Dies kann, wie oben mehrfach erläutert wurde, dadurch geschehen, dass eine Standard-Skelettanatomie, beispielsweise die Skelettanatomie 32, auf die isolierte Person 12 projiziert wird.

Now, referring to 6 an exemplary method for operating the device 10 or for determining at least one mobility parameter of the person 12 is explained:

• The method begins in a start block 46. In a function block 48, a pose of a living being, in the present example the person 12, is captured by the image capturing device 14. In a function block 50, a plurality of prominent skeletal points of the skeletal anatomy of the person 12 are determined by the determination device 18 from the detected pose on the basis of the signals supplied by the image detection device 14. As has been explained several times above, this can be done by projecting a standard skeletal anatomy, for example the skeletal anatomy 32 , onto the isolated person 12 .

In a function block 52, pairs of adjacent prominent skeleton points are defined. In a function block 54, the straight lines connecting the adjacent prominent skeleton points are determined or generated. In a function block 56, a mobility parameter is determined, in this case, for example, a variable that characterizes an angle that is present between the straight lines connecting the adjacent skeleton points and a reference line. In one embodiment, the reference line can be freely selected by the operator of the device 10 . For example, the reference line can simply be the vertical, or a specific straight line connecting two skeleton points. It is preferred if the reference line is formed by the straight line connecting two adjacent skeleton points, one of which belongs to the pair of skeleton points of the straight line whose angular position is to be determined.

In a function block 58, the maximum value or minimum value of the ascertained angle is ascertained for poses of the person 12 that follow one another in immediate succession. The determined maximum values and minimum values are then stored in a function block 60 in memory 22, for example. In a function block 62 an evaluation of the time profile of the maximum values or minimum values of the determined angles stored in the function block 60 then takes place. This can include, for example, determining a gradient and comparing it with a standard value in order to determine a quality parameter therefrom. The result of the evaluation in the function block 62 and/or the maximum value or the minimum value are transmitted in a function block 64 to a processing device arranged remotely from the device 10 . The method ends in a function block 66.

It is understood that the in 6 The method shown is just one of several possible example methods. For example, the method could include repetitions in order to carry out corrections, for example to compensate for an inconsistency. The procedure could also include repetitions in order to be able to determine an average value at the end.

In the 7 and 8th diagrams are plotted in which a movement speed, for example in this case an angular speed dα/dt over time t ( 7 ) or over the angle α ( 8th ) is applied. You can tell 7 , that the angular velocity decreases significantly after about half the recording time t1, which could indicate an orthopedic problem and/or a need for training. Out of 8th one can see that the angular velocity dα/dt collapses at an angle α1, which indicates a specific problem in the area of the angle α1 of the extremity.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 2013/087084 A1 [0007]

Claims (13)

Device (10) for determining at least one mobility parameter (α) of a living being (12), comprising an image capturing device (14) which is designed and set up to capture at least one pose of the living being (12), and with the image capturing device (14 ) connected determination device (18), which is designed and set up to determine a plurality of prominent skeletal points (ay) of a skeletal anatomy (32) of the living being from the recorded pose, wherein the determination device (18) is also designed and set up to at least to define a first pair (41) of prominent skeleton points (e, f) and to determine a mobility parameter (α) therefrom, wherein the mobility parameter includes a variable that characterizes an angle (α) that is formed between a first connecting straight line (40 ), which is spanned by the first pair of skeleton points (41), and a straight reference line (38), characterized in that the determination device (18) is also designed and set up to determine a maximum value and/or a minimum value of the angle (α), an angular velocity (dα/dt) and/or a course of the angular velocity from a plurality of poses and angles that are detected in immediate succession (dα/dt) to be determined. Device (10) after claim 1 , characterized in that the determination device (18) is designed and set up to define a second pair (43) of prominent skeleton points (d, e) and a second connecting straight line (38) through the second pair of skeleton points (d, e) is spanned, to be used as a reference line for the angle (α). Device (10) after claim 2 , characterized in that the first pair of skeletal points (41) and the second pair of skeletal points (43) have a common skeletal point (e). Device (10) according to at least one of the preceding claims, characterized in that it comprises a memory device (22) which is designed and set up to store the maximum value or the minimum value and/or the angular velocity and/or the profile of the angular velocity . Device (10) according to at least one of the preceding claims, characterized in that it comprises an evaluation device (44) which is designed and set up to display a time profile of maximum values or minimum values and/or angular velocities and/or profiles stored at different points in time evaluate the angular velocity. Device (10) after claim 5 , characterized in that the evaluation device (44) is designed and set up to determine a quality parameter from the time profile of the maximum values or minimum values and/or angular velocities and/or profiles of the angular velocities, which characterizes a treatment success. Device (10) according to at least one of the preceding claims, characterized in that it comprises an interface device (28) which is designed and set up to display the maximum value or the minimum value and/or the angular velocity and/or the profile of the angular velocity or if available, the result of the evaluation of the time curve of the maximum values or the minimum values or and/or angular velocities and/or curves of the angular velocities or, if available, the quality parameter to an external processing device (30) arranged remotely from the device (10) to transmit. Device (10) according to at least one of the preceding claims, characterized in that it comprises an output device (24), in particular a monitor, which is designed and set up to display at least the first connecting straight line (40) and preferably the reference line (38) and its To display the relative position graphically in real time and/or to output numerically and/or graphically the quantity that characterizes the angle (α) and/or the angular velocity (dα/dt) and/or the course of the angular velocity (dα/dt) in real time. Device (10) according to at least one of the preceding claims, characterized in that the determination device (18) and, if present, the evaluation device (44) are implemented by a computer with at least one microprocessor (20), at least one memory (22) and program code are. Device (10) according to at least one of the preceding claims, characterized in that the determination device (18) is designed and set up to determine a variable which characterizes a distance between two skeleton points. Device (10) according to at least one of the preceding claims, characterized in that the determination device (18) is designed and set up to determine a boundary condition directly or indirectly linked to the pose together with the determined maximum value and/or minimum value of the angle (α), output, store and/or process the angular velocity (dα/dt) and/or the course of the angular velocity (dα/dt). Method for determining at least one mobility parameter (α) of a living being (12), comprising the following steps: detecting at least one pose of the living being (12) by means of an image acquisition device (14); determining by means of a determination device (18) a plurality of distinctive skeletal points (ay) of a skeletal anatomy (32) of the living being (12) from the detected pose; defining at least a first pair (41) of prominent skeleton points (e, f) by means of the determination device; and determining by means of the determination device (18) a mobility parameter, wherein the mobility parameter includes a variable that characterizes an angle (α) that is formed between a first connecting straight line (40) that is spanned by the first pair of skeletal points (41) and a straight reference line (38), characterized in that the method further comprises the following step or steps: determining from a plurality of directly consecutive poses and determined angles a maximum value and/or a minimum value of the angle (α), an angular velocity ( dα/dt) and/or a course of the angular velocity (dα/dt). Use of an image acquisition device (14), in particular a video camera, in a device according to one of Claims 1 - 11 or in a method according to claim 12 .

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