The present invention refers to a system for movement proprioceptive stimulation, monitoring and characterization, in the field of motor neurorehabilitation.
Spontaneous recovery subsequently to a condition, such as a stroke, is normally limited, which makes post-stroke rehabilitation therapies essential in the functional recovery of the individual. Technology applications to neurological and motor rehabilitation methods focus mainly on robotic and electromagnetic stimulation devices (competitors).
For electromagnetic stimulation, there are different application paradigms. However, results (motor recovery) obtained in clinical trials are modest when compared to traditional rehabilitation therapies based on repetition of specific tasks. Due to the nature of electrical stimuli, either invasive or noninvasive, these can only be applied under medical supervision which eliminates the possibility of outpatient use, thus reducing the intensity of rehabilitation.
Robotic devices allow continuous repetition of specific motor tasks, assisting the patient in the correct execution thereof. However, these devices are of high cost of production and operation, requiring specialized human resources, which prevents outpatient use and democratization. For this reason, they provide a reduced exposure to treatment and therefore a lower possibility of global health gains, as has been demonstrated in clinical studies. However, their use is promising in more restricted cases, as it allows continuous training of specific day-to-day tasks such as opening a door, or a bottle, among others.
The re-habilitation method and system based on the present invention (which shall be hereinafter designated SWORD—Stroke Wearable Operative Rehabilitation Devices) allow a high intensive training due to their outpatient use aiming at the repetition of specific tasks, and it is the only solution capable of providing biofeedback.
Yet compared with the complex high technology robotic devices, the method and system herein referred to as SWORD will lower production costs and require less manpower to operation, resulting in easier spread by patients in need, and maximizing possible health gains.
The method and system herein referred to as SWORD can be used in integrated marketable products (intervention/monitoring), as provided for in the original design of the device, or it may be applied separately in devices directed only to vibratory stimulation or to quantification and monitoring of movement quality.
The main application for this type of product is the area of healthcare, particularly the neurorehabilitation field. Potential users are, on the one hand, health institutions dealing with neurological patients, including rehabilitation centers and Neurology departments and, on the other hand, patients themselves. Conditions which may benefit from this technology are e.g. stroke, head and spinal cord trauma, lesions after neurosurgery, all with high annual incidence, prevalence and impact on morbidity measured by Quality Adjusted Life Years (QALYs).
In Europe, according to WHO data, health services spend about 5% of budget on the treatment of stroke patients and the annual value of Disability Adjusted Life Years (DALYs) is between 5 to 9 years per 1000 inhabitants.
Another segment is the basic or clinical science activity, wherein variations of products may be presented, developed as a standard vibratory stimuli management tool and motor quantification tools on an outpatient basis. It is a segment of smaller dimension but medium-term significant due to its possible benefits in the range of applications and validation of clinical indications for this technology.
The outpatient movement quantification system can also be applied to products aimed at entertainment market segments (e.g. dancing, video games, interactive TV, 3D cinema), in sports and motor performance improvement for competition purposes.
The present invention combines several unique characteristics within the Neurorehabilitation scope. Compared with the prior art, it allows:
Prior art rehabilitation methods, which allow obtaining better results in terms of functional recovery, share at least one of the following characteristics:
These three characteristics are present simultaneously in the rehabilitation paradigm underlying the method and system herein referred to as SWORD, thus their outpatient use shall allow an increase on training intensity, monitored task repetition and its feedback to the patient, family and attending physician, gathering all conditions enhancing the achievement of an effective functional recovery.
Still regarding current prior art, technology applications to neurological and motor rehabilitation methods focus mainly on robotic and electromagnetic stimulation devices (competitors).
For electromagnetic stimulation, there are different application paradigms, however, results (motor recovery) obtained in clinical trials are modest when compared to traditional rehabilitation therapies based on repetition of specific tasks. Due to the nature of electrical stimuli, either invasive or noninvasive, these can only be applied under medical supervision which eliminates the possibility of outpatient use, thus reducing the intensity of rehabilitation.
Robotic devices allow continuous repetition of specific motor tasks, assisting the patient in the correct execution thereof. However, these devices are of high cost of production and operation, requiring specialized human resources, which prevents outpatient use and democratization. Due to this fact, they provide a reduced exposure to treatment and therefore a lower possibility of global health gains, as has been demonstrated in clinical studies.
Some prior art documents of the present invention are hereinafter described.
U.S. Pat. No. 5,575,761(A) describes a device for variable vibratory massage of different parts of the human body.
U.S. Pat. No. 6,093,164 (A) discloses a sleeve for applying low frequency and diffuse vibration onto the limbs.
U.S. Pat. No. 6,878,122 (B2) discloses a robotic device for motor facilitation and simulation through vibratory stimuli in affected areas of the body.
WO2008094485(A2) discloses a portable device for the application of vibrations and thermal variations in painful areas of the body.
WO2010028042(A1) discloses a portable device for the application of vibrations and thermal variations in painful areas of the body.
US2010004709(A1) discloses a device for increasing cerebral perfusion through stimulation of peripheral nerves with various stimuli and vibration of the head.
None of the above documents contains the full set of features present in the invention herein described such as:
The device herein proposed is innovative, not only in its specifications, but also in terms of its approach to rehabilitation. According to the latest revisions of the prevailing rehabilitation paradigms in strokes, the method and system herein referred to as SWORD assert themselves as a new approach. The intervention of vibratory stimuli, either continuously or at predefined intervals, is not object of study in neurorehabilitation technology, but nevertheless, its CNS (Central Nervous System) excitatory ability has already been proven.
The combination of vibratory stimuli action with patient response assessment represents a further innovation.
Therefore the device and methods herein proposed correspond to an unique and emerging technology.
FIG. 1—Shows an example of modular integration of the system herein referred to as SWORD, for the upper limb.
1. Main module located on the shoulder for movement control, proprioceptive stimulation and quantification on the shoulder girdle
2. Module for movement control, proprioceptive stimulation and quantification on the arm region
3. Module for movement control, proprioceptive stimulation and quantification on the forearm region
4. Module for movement control, proprioceptive stimulation and quantification on the hand region
FIG. 2—Constituent Units of each modular element of the system herein referred to as SWORD.
5. Movement quantification and characterization unit
6. Unit for global control, communication and synchronization among modules
7. Proprioceptive intervention unit
FIG. 3—Internal operation of constituent Units of each Module of the system herein referred to as SWORD. Movement quantification and continuous monitoring unit (5):
8. Gyroscope
9. Accelerometer
10. Magnetometer
11. Sensor Fusion block
12. Movement characterization block
Unit for global control, communication and synchronization among modules (6):
13. General control block
14. Communication and synchronization block
Stimulation or intervention unit (7):
15. Proprioceptive control and stimulus definition block
16. Elements for proprioceptive stimulation
FIG. 4—Example of the arrangement of the modules and stimulation elements on the upper limb.
FIG. 5—Example of the arrangement of the modules and stimulation elements on the lower limb.
17. Module for movement control, proprioceptive stimulation and quantification on the thigh region
18. Module for movement control, proprioceptive stimulation and quantification on the leg and knee region
FIG. 6—Example of the arrangement of the modules and stimulation elements on the torso.
19. Module for movement control, proprioceptive stimulation and quantification on the torso region, namely the abdomen
FIG. 7—Example of the conceptual model of earth and module axis systems used to estimate the rotation matrix.
20. xx axis of the earth axis system.
21. yy axis of the earth axis system.
22. zz axis of the earth axis system.
23. Rotation matrix transforming the earth axis system into the module axis system and vice-versa.
24. xx axis of the module axis system.
25. zz axis of the module axis system.
26. yy axis of the module axis system.
The rehabilitation method based on the device herein referred to as SWORD allows a high intensity straining due to its outpatient use, it is intended for the repetition of specific tasks, and is the only one able to provide biofeedback in terms of the characterization of the movement carried out and in terms of the quality and quantity thereof.
Yet compared with the complex high technology robotic devices, the method and system herein referred to as SWORD requires less manpower to operation and may be more easily spread by patients in need thereof, thus maximizing potential health gains.
The rehabilitation paradigm underlying the object of the invention, the method and system herein referred to as SWORD, is based on extracorporeal application of proprioceptive stimuli, either intermittently or continuously, of various kinds (vibration, thermal, pressure) onto the main joints of the affected side, on the one hand, and on the correct quantification and qualification of any type of movement performed in an outpatient setting during and after the stimulus. The integration and communication between the stimulation system and quantification system allow a dynamic configuration of the two components.
One may also export continuous monitoring data on the movement in order to assist the therapy decision in rehabilitation medicine.
The system may be described according to several levels of complexity. At a macrostructural level, it consists of segmental modules. Each of these modules is composed of Units, each having a primary function. Finally, each unit is composed of several blocks which articulate according to the function performed by the respective unit.
The system herein referred to as SWORD is usually composed of several interconnected modules. Each module is responsible for the proprioceptive stimulation and characterization of the movement carried out by a body segment. The number of modules to be used in each individual depends on the body segments intended to stimulate and from which quantitative and qualitative information on the movement performed on an outpatient basis is intended for collection.
Communication among modules is bi-directional. All modules communicate with each other and share information regarding the stimulation mode in use and movement performed. Thus, each module knows the current and past status of the other modules, thus allowing a dynamic configuration of the proprioceptive stimuli to be used. This communication methodology allows the proprioceptive stimulus to be applied only onto the body limb responsible for the erroneous execution of the motor task. Biofeedback transmitted could thus be directed only to a part instead of the generality of bodily elements, notifying the user in detail on the location of the error. Additionally, such communication is essential in order to update the biomechanical model at each time instant, since there is a direct dependency relationship between the several body elements.
Each of the individual modules (e.g. 1, 2, 3, 4, 17, 18, 19) is dedicated to stimulate a particular segment of the human body and to collect kinetic information from the same segment, as shown in
The main module (1) is the one closest to the center of body gravity and integrates the information collected by all modules of said limb, and controls the stimulation mode at each distal module and sets whether stimulation should occur simultaneously, randomly or according to predetermined and programmed patterns.
As for the internal operation of each module, the system typically consists of three components overlapping and connected as shown in
As far as the communication among modules is concerned, it may occur with or without wires, depending on the wearable solution chosen. In the case of wireless communication and synchronization among modules, this is done by low energy elements in order to maximize the device's autonomy.
Thus, for the upper limb (
For the lower limb (
In certain situations additional modules located on the head, chest or abdomen regions may be required (
According to needs, the system may operate only on the upper limb, only on the lower limb, only on the torso, only on the head or with all possible segmental components or combinations thereof.
Depending on the needs for collecting kinetic or stimulation information, there may be a saving of modules at each segment. In this situation, the position of the proprioceptive stimulation elements (16) is maintained, but the total number of modules per system may be reduced.
Each continuous movement quantification and monitoring unit (5) includes gyroscopes (8), accelerometers (9) magnetometer (10), sensor fusion block (11) and a movement characterization block (12) and is responsible for all kinetic data collection from the respective segment and processing thereof, for the purposes of transferring them to the unit for global control communication and synchronization among modules (6).
Each unit for global control, communication and synchronization among modules (6) contains a general control block (13) and a communication and synchronization block (14).
The stimulation or intervention unit (7) includes a proprioceptive control and stimulus definition block (15) and proprioceptive stimulation elements (16), the latter being placed on the site, or sites, of the human body intended to stimulate.
As described in
Elements 8, 9, 0.10 are collecting structures of kinetic information (quantitative and qualitative information), which project their data into the sensor fusion block (11).
Movement qualification is defined as characterizing the displacement of the limb in space in terms of translation and rotation. This qualification is obtained by merging the measurements from the magnetometers (10), accelerometers (9) and gyroscopes (8) incorporated in the device using stochastic estimators for such purpose. The movement is subsequently compared with the movement trained by the patient in a clinical setting at block 13. The parameterization of the trained movement is obtained through the device herein referred to as SWORD, in combination with traditional rehabilitation therapy. This information is stored in block 13.
The sensor fusion block (11) represents the mathematical algorithm, which based on three independent measurements (acceleration, angular rotation and magnetic field) calculates translation and rotation in space of the module and body segment to which it is associated. This block 11 receives unidirectional information from elements 8, 9 and and projects it into block 12. The mathematical algorithm underlying the sensor fusion block is based on the estimate of a rotation matrix (23) between two reference axis, which relate to the earth's reference axis system and to the rotating module's axis system (
The estimate of the error in the measurements from the gyroscope results from a geometrical comparison drawn between the earth's axis system and reference vectors obtained from the magnetometer (12) and accelerometer (9). The noise in measurements of angular rotation is also present in the earth's axis system, since this is obtained by multiplying the rotation matrix (23) by the module's axis system.
Although measurements from both blocks also contain noise, this will always be independent from that observed in measurements from the gyroscope (8). In order to estimate the error in the measurements relating to angular rotation associated with (22), the later is compared with the gravitational vector obtained by the accelerometer block (9). Comparison is performed by the external product, which will provide the magnitude and direction of the error in the measurements of angular rotation. Similarly, in order to estimate the error in the angular rotation measurements relating to (20) and (21) of the earth's axis system, the later is compared with the magnetic field vector obtained by the magnetometer block. The comparison is also made using the external product between both vectors. In order to complete the compensation process, both error components obtained are applied to a proportional-integral type controller from which error-free measures of angular rotation shall result and which may be used in time discrete integration of the rotation matrix (23). Depending on the rating required to represent the three-dimensional rotation of the module in space, the rotation matrix may be transformed into Euler angles or quaternions.
This error compensation process has the advantage of being efficient in terms of processing time required, which can be implemented in a microcontroller operating in real time. Another advantage lies in its proficiency in estimating the error in the measurements of the gyroscope.
The movement characterization block (12) represents the mathematical algorithm combining rotation and translation measurements from the sensor fusion block (11) with the biomechanical system representative of the user. This block displays vectors as output which mathematically describe the movement performed. This block 12 receives unidirectional information from block 11 relative to translation and rotation in space of the segment intended to be characterized in terms of movement. Block 12 sends and receives information to and from block 13. The mathematical algorithm transforms, by means of the rotation and translation operations, each vectorial element of the biomechanical system. The transforming element represents the rotation of a reference axis in three-dimensional space and may be present as quaternions, rotation matrices, or Euler angles. The transformed element may be any position of interest in the biomechanical system defined within three-dimensional space.
Block 13 (
The internal logic is established through the use of a microcontroller which is the main component of the general control block (13) of the unit for global control, communication and synchronization among modules (6).
The movement carried out, characterized by the dynamics on points of interest defined and calculated at the movement characterization block (12) is compared with metrics from a motor performance perceived as being normal. Information regarding a deviation in the quality of the movement performed is converted into a proprioceptive stimulus, specified according to the body element which caused an abnormally performed movement.
Block 13 sends the dynamics definition of the applicable proprioceptive stimulus to block 15. Block 15 performs the interface between block 13 and proprioceptive stimulation elements (16).
The proprioceptive control and stimulus definition block (15) adjusts the modulated signal from the general control block (13) so as to obtain an efficient transduction for the proprioceptive stimulation elements (16). In the case of stimulation being based on vibration, the signal from the microcontroller shall be adapted in terms of current so as to be properly replicated in topology by vibration motors.
As far as the communication with modules is concerned, it may occur with or without wires, depending on the wearable solution chosen. In case of wireless communication/synchronization among modules, this is done by low energy elements in order to maximize the device's autonomy.
Main modules are to be understood as, for example, the module placed on the shoulder, in the case of the upper limb, and the module placed on the thigh in case of lower limb. The remainder modules communicate with each other via an internal communication network. All modules are provided with a transmitter and receiver. Main modules are provided with information storage systems.
The extra-module communication takes place among the main modules and the analysis software of the physicist responsible for the treatment plan. This communication is bi-directional and allows obtaining data concerning outpatient use from the device handled by the user. It also allows configuring module network in terms of movement characterization and stimuli definition according to the treatment plan specified by the physicist. The internal communication network exchanges information concerning rotation and translation of each sensory element in three-dimensional space, in order to allow for a mapping of various body segments in a complete biomechanical model, able to represent movement dynamics, to take place in the movement characterization block (12) of each module. The exchange of information among modules also includes the definition of proprioceptive stimuli being applied in each module. This component allows a rhythmical proprioceptive stimulation, since each module knows the sequence and timing of each proprioceptive stimuli in each module.
The device also allows its rapid configuration through communication between the main module and a personal computer, using for this purpose a software specifically developed. In terms of device configuration, it is possible to set the stimulation mode from continuous to intermittent and, should the latter be selected, it is possible to configure the intervention range. Another possibility is configuring the amplitude of the stimulus, should these be vibration-based, and should they occur synchronously or asynchronously across all modules. This software also displays movements performed by the patient after stimuli and the assessment thereof compared with movements made in clinical setting. Dynamic configuration of module network on the upper limb is made e.g. by the main module placed on the shoulder. Dynamic configuration of module network on the lower limb is made e.g. by the main module placed on the thigh. Main modules are responsible for the aggregation of information from the network which, combined with the previous definition of therapy, allows a better adjustment of proprioceptive stimulus to the relevant situation. The previous definition of therapy is performed by the software available to the physicist performing synchronization with the network by means of both main modules.
In a preferred embodiment, each module includes a portable power supply that will allow using the device for several hours or more. Total autonomy shall depend on the configuration of the device in terms of intervention mode. Batteries may be included in the same housing of modules and are preferably rechargeable via USB connection to a computer or to a power outlet (through the use of a specific adapter).
Devices for stimuli application (e.g., vibration, tactile, thermal, painful stimuli, among others). In case of vibration stimulus, it may be carried out by means of vibrating motors controlled in terms of stimulus amplitude and frequency by means of the voltage applied across its terminals. Setting the stimulation is performed by combining three variables: vibration frequency, vibration amplitude and interval between stimuli. If the operating mode is specified as continuous, the definition of the stimuli will depend only on two variables: vibration frequency and vibration amplitude.
Positioning of proprioceptive intervention elements will depend on the configuration selected and on the limb intended to rehabilitate: upper or lower limb. Should vibratory stimuli be used, one possibility is to place a vibration motor at each bone eminence in a position close to the main joints of the upper limb (shoulder, elbow, wrist, carpus and hand) and lower limb (hip, knee, ankle, tarsus and foot).
The use of this device right from an early stage after a stroke, and with no time restriction, may result in major benefits for Neurorehabilitation and, by democratizing access to this technology, a social impact and objective gains in healthcare shall be possible. This contribute is enhanced by other features such as lower cost of production and operation when compared to other technologies, energy autonomy and the possibility of outpatient use, handled by family members and in the future being embedded in garments.
Taking the rehabilitation process of patients with neurological deficits after a stroke into consideration, the application of this technology enables a new generation of processes herein identified:
1) traditional rehabilitation plans may now be enhanced through outpatient use of the device herein referred to as SWORD
2) all outpatient activity may now be monitored, both in real time and pre-recorded modes, using for such purpose, for example, Bluetooth technology in its low power consumption version.
3) new algorithms for clinical decision may be created based on monitoring data provided by the system and method herein referred to as SWORD
4) rehabilitation plans may be designed and tested which progressively include more outpatient activities without loss of therapeutic intensity
The application of the system and method herein referred to as SWORD allows a radical change. For the first time, new devices may come to life with the following characteristics:
The present invention shall thus allow outpatient use combining the possibility of vibratory stimulation and continuous characterization of movement performed by a deficient body segment, as well as the provision of information collected to the patient and responsible physicists through specific software.
Number | Date | Country | Kind |
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106424 | Jul 2012 | PT | national |
Filing Document | Filing Date | Country | Kind |
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PCT/IB2013/055419 | 7/2/2013 | WO | 00 |