DESC:FIELD OF INVENTION
The present invention relates to a portable, wearable and battery-operated prognostic system and
method for assessing muscle activity or muscle strength, and the exact range of motion of upper and lower extremities during physiotherapy sessions. Apart from the extremities, the same technology can also be used for other body parts such as the back, neck, etc.

BACKGROUND OF THE INVENTION
Post-operative physiotherapy plays a major role in the recovery of post-trauma and post-operative
patients. Physical exercises that are performed during physiotherapy sessions aim to encourage movement or the range of motion of different extremities and other body parts such as back, neck, etc., and also improve muscle function. Patient compliance with treatment is an important factor that influences final functional outcome as it is evident that compliant patients have better and faster outcomes than non-compliant patients.

Accurate and reliable assessments of body movements, based on range of motion (ROM) and electromyography (EMG), are not only critical for the diagnosis and characterization of neuro-muscular, musculo-skeletal disorder conditions, improvement of injured joints, tracking progress of physical therapy and evaluation of the effects of physical exercises, but also help in enhancing patient compliance resulting in better and faster recovery.

Most applications of ROM and EMG in physical therapy regime are restricted to hospital and clinical settings instead of monitoring real-time using portable devices. Portable training devices that solely incorporate motion tracking and analysis suffer from lack of consistent, reliable data and only serve as approximations of the true nature of actual physical stress in a body. It is also seen that the existing devices are either bulky in design or are not designed for usage during physiotherapy sessions. These can be used only in non-dynamic conditions when the body part undergoing physiotherapy is not in motion. Also, currently in most parts of the world, there is no scientific and methodical manner of documenting and reporting the recovery of patients undergoing physiotherapy.

Several approaches have been adopted in the prior-art to address this issue. US9498128B2 discloses a garment borne sensor system incorporated with EMG sensors for measuring the amplitude of electromyography signal. However, this publication does not disclose real-time measurement of range of motion or the use of EMG for muscle strength recovery analysis.

US6643541B2 discloses a flexible wireless patch EMG sensor, for the measurement of EMG of a patient suffering from Parkinson’s disease, with a provision for over-the-air communication between a plurality of sensors and a receiving system. However, specific muscle strength analysis for various joints of the body is not disclosed.

Wearable biometric monitoring systems, such as wrist wearables from companies such as Nike and Fitbit which have become popular in recent years have been disclosed in US7793361B2 and US20140039804A1. These publications disclose the concept of placing biometric sensors in a wrist garment or similar apparel, for measuring physiological metrics such as electromyography. However, these do not disclose real-time measurement of muscle activity.

US20100185398A1 and US20060136173A1 disclose systems for monitoring athletic activity, comprising wearable sensors for analyzing athletic performance by utilizing global positioning satellite data. However, these publications do not disclose the measurement of EMG and ROM.

Accordingly, there is a need for accurate and reliable real-time measurements of ROM and EMG by employing simple, wearable, portable, user-friendly devices. These devices will help achieve patient compliance through a detailed summary of the patient’s progress based on the analysis of muscle activity and range of motion. Tracking these parameters can play an important role in the rehabilitation of patients undergoing physiotherapy. It is a proven concept that bio-feedback helps in motivating patients resulting in faster recovery. The present invention satisfies these needs as well as others, and is generally an improvement over prior art.

OBJECT OF THE INVENTION
The object of the present invention is to develop a smart wearable system for the measurement of range of motion and electromyography both remotely and also in real-time, and present the analysed results to the end users and medical practitioners in real-time, in the form of detailed scientific reports, with just a click of few buttons.

SUMMARY OF THE INVENTION
The present invention relates to a wearable prognostic system for monitoring and tracking the recovery of patients undergoing physiotherapy by detecting the range of motion of upper and lower extremities and other parts of the body. The corresponding muscle activity at various joints of the body can be monitored both in real-time and remotely, with the aid of algorithms and tools based on Artificial Intelligence and Machine Learning. A detailed scientific report is generated on exercise performance as per the schedule and also status of recovery which can be shared with the doctor, physiotherapist, paramedic, patient or their caregivers post- each session.

BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1. Components of wearable device;
Fig. 2. Various extremities of human body where the device can be worn during usage;
Fig. 3. Perspective view of the wearable device;
Fig. 4. Sample displayed data on the dashboard of a receiver device (mobile phone, tablet, desktop);
Fig. 5. Method of using the wearable device by a doctor, physiotherapist, caregiver, or paramedic;
Fig. 6a. Remote physiotherapist’s dashboard;
Fig. 6b. View of remote physiotherapist’s “On-click” screen to check progress of patient’s recovery;
Fig. 6c and Fig. 6c-2. View of remote physiotherapist’s screen for prescribing exercises to patient remotely;
Fig. 7. The various gamification themes available on the receiver device (mobile phone, tablet, desktop);
Fig. 8. Overall architecture for ROM and EMG acquisition, processing and transmission;
Fig. 9. Flowchart for range of motion acquisition, processing and transmission;
Fig. 10. Flowchart for EMG signal acquisition, processing and transmission;
Fig. 11-1 to 11-5. Various templates for the generation of reports to assess the progress of the patient’s recovery;
Fig. 12. Flow chart to assess Active time and Hold time while exercising; and
Fig. 13. Flow chart to assess Consistency of information.

DETAILED DESCRIPTION OF THE INVENTION
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one skilled in the art to which the current disclosure belongs. The term “wearable device” and variations thereof as used herein are used synonymously with the terms “prognostic device”, “wearable prognostic device”, “wearable prognostic system” and variations thereof, and are open, non-limiting terms. The terms “doctor”, “medical practitioner”, “physiotherapist”, “paramedic”, and “caregiver’ and variations thereof used herein may be interpreted interchangeably. Also, the terms “patient”, “subject” or “end user” and variations as used herein may be interpreted interchangeably.

The present invention discloses a portable and wearable prognostic system for the measurement of Range of Motion (ROM) and Electromyography (EMG) during and post- physiotherapy sessions. This system quantifies scientifically the measure of recovery of patient undergoing physiotherapy based on certain researched upon metrics, and generates custom designed scientific reports that can be shared with the doctors, physiotherapists, caregivers and patients, as and when needed. The invention also aims to help the patients perform physiotherapy sessions remotely after prescription of exercises by the physiotherapist from a remote location. According to an embodiment of the present invention, the patient subsequently receives the scheduled exercises over a mobile phone, a tablet, or a desktop using a custom-made application. Upon completion of physiotherapy sessions, detailed shareable scientific reports showing the status of recovery of the patient undergoing physiotherapy can be generated. The complete database of the patient’s recovery can be maintained in a standard manner by the user.

According to the embodiments of the present invention, the components of the wearable device (100) of the present invention as shown in Fig. 1, comprise the top enclosure of an upper module (101); a button (102) for turning said device on or off; the bottom part for upper and lower modules (103); the top part for a lower module (104); and straps (105) attached to the upper module and lower module. According to some embodiments of the present invention, the wearable device may have two to five modules including at least one upper module and one lower module. The wearable device of the present invention can be held on to the extremities shown in Fig. 2 with the help of the straps (105). Fig. 3 is a perspective view of the wearable device with two modules - an upper module (101) and a lower module (104) that are connected by an interconnecting flat ribbon cable (107), EMG cable, and disposable EMG electrodes. As shown in Fig. 3, the information from the wearable device is received by a central monitoring unit through a cloud-based storage means, which is subsequently received by a remote monitoring receiver, which can be a mobile phone, a tablet, or a desktop. In an alternate embodiment, the information from the wearable device can be stored on a local storage medium and used for assessment of the user’s progress of recovery using a custom-made set of instructions.

According to an embodiment of the invention, said enclosure of the prognostic device is made up of a plastic material such as ABS (Acrylonitrile Butadiene Styrene) and the like. Custom designed straps (105) are made of soft and hard Velcro material, stitched with a fabric such as a cotton fabric or any other bio-compatible material. Metal rings or plastic rings (106) are attached at one end of the straps (105). These straps (105) are designed in a manner to enable attachment of the wearable device to the required joint in the upper and lower extremities, and other parts of the body, such as elbow (201), ankle (202), hip (203), wrist (204), shoulder (205), and knee (206) shown in Fig. 2. According to an embodiment of the invention, said modules of the wearable device, are placed on either side of the joint wherein the ROM and EMG are to be measured. It further comprises at least three surface EMG electrodes for single channel EMG signal acquisition. According to other embodiments of the present invention, the number of electrodes may be five or more to achieve multi-channel EMG signal acquisition depending on the need by the user to simultaneously assess more than one muscle, for instance in sports or gait training. For single channel EMG signal acquisition, two electrodes are positioned on the specific muscle whose strength or activity is to be measured, and one electrode which acts as a reference electrode is positioned on the bony prominence of the body, which can be for instance, at the elbow (201) or the wrist (204) for upper extremities, or on the knee or ankle for lower extremities. Said electrodes are connected to the lower module (104) using a dedicated EMG cable and a connector. The custom designed electronics include a bioamplifier, micro-electromechanical system (MEMS), motion sensors such as accelerometer and gyroscope, power supply units and wireless transceiver. The device is also equipped with magnetometers that help in increasing the accuracy of measured parameters using novel and custom designed proprietary instructions or algorithms. According to a preferred embodiment of the present invention, said device comprises two accelerometers, two gyroscopes, a magnetometer, and a bioamplifier. All circuits are designed on custom designed printed circuit boards (PCBs) made up of common FR4 material. The EMG cable that can operate well upto a temperature of 40 degree Celsius and a pressure ranging between 86 KPa and 106 KPa, is procured off-the-shelf. The EMG electrodes procured off-the-shelf are medical grade electrodes having foam adhesive and are connected to the EMG cable using press-fit mechanism. As shown in Fig. 3, said prognostic system comprises at least two modules- an upper module (101) and a lower module (104), and disposable EMG electrodes connected to one of the modules (lower module) via a EMG cable and a connector, and is powered by a rechargeable battery such as a lithium polymer battery which is present in the upper module (101). The modules of the invention may either be connected with an interconnecting flat ribbon cable (107), or may be connected to each other and/or to receiver modules wirelessly. The information is received by a central monitoring unit through a cloud-based storage means or on the local server of a computer.

The wearable device can be charged using any off-the-shelf charging means such as a safety certified 5V output voltage mobile phone charger or a USB charging port. The system is designed to consume very low power and is IoT enabled for remote monitoring via a communication device such as a mobile phone, a tablet, or a desktop as shown in Fig. 4. Fig. 5 illustrates the method of using the invention by a caregiver, a paramedic or a doctor using a mobile phone, a tablet, or a desktop.

According to some embodiments of the present invention, the system enables a physiotherapist, a medical practitioner, or a caregiver to set up the exercise protocol from a remote location, which is to be followed by the patient, subject or end user. The program adherence can be tracked by said physiotherapist, medical practitioner, or caregiver. The user interface at the physiotherapist and patient’s end includes information such as date, time, patient ID, number of sessions, adherence indicator, etc., as shown in Fig. 6a, Fig. 6b, Fig. 6c, and Fig. 6c-2. The various real-time dashboards along with gamification themes that are available for the physiotherapist or patient are illustrated in Fig. 7.

According to another embodiment of the present invention, the prognostic system comprises a wearable device which enables monitoring parameters such as EMG and ROM along with the metrics derived through the use of embedded sensors, novel in-built proprietary instructions or algorithms, digital signal processing and filtering, through a mobile phone, tablet, or desktop-based application. Fig. 8 shows the architecture for data acquisition, processing and transmission of the measured ROM and EMG to the receiver running the custom application. Said device is aided by novel proprietary instructions or algorithms and digital signal processing techniques, and can be employed, but not limited, to the detection of exact range of motion of the joint and individual muscle activity at joints such as elbow (201), ankle (202), hip (203), wrist (204), shoulder (205), and knee (206). Fig. 9 shows the flowchart indicating the process of acquisition, processing and transmission of ROM values using the wearable prognostic device of the present invention. The implementation of ROM measurement includes the following steps: reading of the raw values from onboard accelerometer and gyroscope and use of an optimal estimation Kalman filter to arrive at the estimate of an angle. Kalman filter uses a series of measurements observed over time and produces estimates of unknown variables that tend to be more accurate than those based on a single measurement alone. According to the embodiments of the present invention, the information from accelerometer and gyroscope is used for estimating a joint probability distribution over the variables for each time-frame, and calculation of the angle. An adaptive repetition recognition algorithm recognizes the pattern of the exercise and counts the number of repetitions while exercising. Proprietary in-built algorithm computes physiotherapy aiding parameters such as hold time and active time as shown in Fig. 12.

According to some embodiments of the present invention, the wearable prognostic device also has the capability to auto-detect the change in the orientation and modify the input parameters required to calculate the angle. A de-rotation matrix is used to bring the device to its reference position for joints which have uneven surface. The present invention also computes the overall range of motion based on the values of the upper module (101) and the lower module (104), type of exercise, exercised joint and the position of the user. Magnetometer calibration is done by an additional monitoring feature which enables monitoring the movement of the device in all the three axes to validate the calibration process. The overall accuracy for range of motion was calculated to be 94%. The wearable prognostic device allows the user to correct initial angle and select the type of exercise, muscle, number of repetitions and even set recovery targets and receive indications about attaining or not attaining exercise targets, i.e., ROM values and number of repetitions, in the form of an audio and/or visual display. The device calculates the hold time of the exercises, total session time, active time, etc. among various other parameters. The device is also capable of identifying and recording the consistency of movement of the body parts which can be correlated with the recovery of the patient, as shown in Fig. 13. The identification of “velocity of movement” commonly known as “Pace” is another important feature of the present invention and based on this metric, the recovery of the patient is calculated. The extent of recovery is indicated through a colour coding, typically by employing colours such as blue, green, and red, but not limited to the same, wherein red indicates poor recovery, blue indicates moderate recovery, and green indicates good recovery, as shown in Fig. 6b. Said device provides the exact reference values or thresholds for ROM for the predefined body parts which undergo physiotherapy.

Fig. 10 shows a flowchart depicting the EMG signal acquisition, processing and transmission. EMG signal is sampled at 1000 Hz, and processed data is sent in real-time to the receiver with a delay of about 20 ms. EMG signal processing uses a combination of digital filters. The bandwidth of the processed signal is about 460 Hz. The digital filters also nullify the powerline noises present in the surroundings using a series of Notch filters. Said device can detect the EMI sources being turned on and compensate for the introduced offset when the EMG electrodes are placed on the user's body, provided the user is in idle position. Said device also has the capability to detect high EMI interface in the ambience and bring it down to its normal value. The EMG correlation of the device of the present invention has been made with respect to a gold standard EMG acquisition device. The biometrics was calculated to be 96%.

According to the embodiments of the present invention, in order to assess the muscle activity or strength, the prognostic device enables monitoring of parameters such as ROM and EMG both in real-time and remotely during the ongoing physiotherapy sessions. The device of the present invention also allows the user to set preset goals, number of repetitions, EMG amplitudes, ROM and hold time, prior to commencing the exercise. Based on recorded and analyzed data of ROM and EMG, the progressive recovery of the patient can be monitored and daily, weekly, monthly and overall reports can be generated. Sample templates of the generated reports are illustrated in Fig. 11-1 to Fig. 11-5. Parameters such as hold time, active time, consistency, smoothness, speed of motion, and controllability of motion can also be calculated and displayed in the report. Hold time and active time are calculated as shown in Fig 12, consistency is calculated as shown in Fig. 13.

The muscle activity analysis includes on-off time of the muscle firings, slope and amplitude of the acquired EMG signal, and spectral analysis of the same to identify various muscular ailments. The device of the present invention also enables detection of minute flickers in muscles which generally go unnoticed when conventional devices are used.

According to the embodiments of the present invention, the components of said device are battery operated, and are connected wirelessly to a smartphone application (IoS, Android or any other mobile phone with the trending operating system) or a desktop computer, laptop, tablet PC and the like. The device can be worn by the patient undergoing physiotherapy either during the session or at the start or afterwards to monitor the session performance. The data is transmitted from said device to smartphone via Bluetooth (BLE) protocol, or to a desktop or other data transfer devices. The acquired data is processed onboard, encrypted, and sent to the server. Further analysis using proprietary instructions or algorithms are executed at the remote server to extract information and plot graphs. Also, other processing algorithms are used to extract more information as needed, to track the recovery of the patient. The processed and analysed data is retrieved on a mobile phone, a tablet, a desktop or any other smart device, and can be used to display detailed customized report using any reader software format, preferably a PDF format. Said wearable prognostic device also comprises a provision to include feedback or comments from the physiotherapist, medical practitioner, paramedic, or caregiver. Customized report selection is possible via the proprietary App for a specific interval of time, for example, daily, weekly or monthly progress analysis or overall analysis for the entire duration of the physiotherapy sessions. The invention possesses variable gain features for accurate data acquisition, and also has real-time zoom-in or zoom-out display features as well as better visualization by the user. The reports can also be seamlessly integrated with electronic medical or health records (EMRs and EHRs) using application programming interfaces (APIs).

According to some embodiments of the present invention, multiple patient monitoring is possible in a sequential manner with just a click of a button on the receiver device through multiple devices communicating to the receiver device such as a mobile phone, a tablet, a desktop, and the like.

According to a preferred embodiment of the present invention, the present invention relates to a system for monitoring and tracking the recovery of an individual undergoing physiotherapy comprising a wearable device comprising of two or more modules, including an upper module (101) and a lower module (104); wherein said upper module (101) and said lower module (104) are positioned on the external side of a human joint using cotton straps (105), connected by a wired connecting means using an interconnecting cable or wirelessly; and three to five disposable EMG surface electrodes that are connected to the lower module (104) through an electromyography (EMG) cable and a connector; custom-designed electronics, and a button to turn the device on or off. The custom-designed electronics comprise components such as a bioamplifier, MEMS, motion sensors, a power supply unit, and a receiver device. Said monitoring system also comprises a user interface, cloud-based data storage means, and a remote monitoring unit for signal acquisition and analysis. The device reads the raw value from onboard motion sensors and uses an optimal estimation Kalman filter to arrive at the estimate of an angle. An adaptive repetition recognition algorithm recognizes the pattern of the exercise and counts the number of repetitions done during an exercise. The in-built proprietary algorithm computes physiotherapy aiding parameters such as hold time and active time. The monitoring system of the present invention also computes the overall range of motion based on the values of the upper module (101) and lower module (104), exercise type, joint selected, and the position of the user. EMG signal acquisition and processing are executed by sampling the EMG signal at 1000 Hz, and sending the sampled and processed data real-time to the receiver device. The real-time data is transmitted from the wearable device to a mobile phone, desktop, tablet, or PC wirelessly. The acquired data is then sent to a remotely located server through Wi-Fi and analyzed using various proprietary instructions or algorithms to generate a progress report on the recovery of the patient which can be reviewed by a physiotherapist, a medical practitioner, or a caregiver.

The wearable device of the present invention can be effectively used in the areas of orthopedic, musculoskeletal disorders, neurological disorders, trauma, chronic diseases, sleep apnea, facial abnormalities such as facial palsy, pulmonary and respiratory disorders, and other ailments such as urinary incontinence etc. to name a few but not limited to the same. It can also be used for sports rehabilitation, sports or gait training, and pediatrics. Said wearable prognostic device of the present invention may find extensive use in fitness, wellness, geriatric care centers, and allied areas.
,CLAIMS:We Claim:
1. A system for monitoring and tracking the recovery of an individual undergoing physiotherapy comprising:
i) a wearable device comprising of
a) two to five modules, including atleast one upper module and one lower module;
b) straps for positioning said upper module and said lower module on the external side of a human joint;
c) a connecting means comprising an interconnecting cable;
d) electromyography (EMG) cable;
e) three to five disposable EMG surface electrodes;
f) a plurality of sensors comprising two accelerometers, two gyroscopes, a magnetometer, and a bioamplifier;
g) a data processor; and
h) a wireless transceiver unit;
ii) a user interface;
iii) cloud-based data storage means; and
iv) a remote monitoring unit for signal acquisition and analysis.

2. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein the progress and protocol adherence of individual can be assessed by monitoring and tracking the exercise schedule of the individual.

3. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein said wearable device measures the range of motion (ROM) and electromyography (EMG) at the body joint or extremity during and post-physiotherapy sessions by means of said sensors and in-built processing instructions.

4. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein said wearable device monitors muscle activity at various joints of the body in real-time.

5. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein said wearable device detects change in orientation and input parameters required to calculate the angle at the extremities.

6. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein said user interface enables real-time monitoring and generation of reports.

7. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein said user interface enables transmission of data between said wearable device and said receiver device through a cloud-based storage means.

8. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein a detailed scientific report of the progress of an individual’s recovery is generated based on the ROM and EMG measured during the performance of the exercises, using in-built instructions.

9. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 7, wherein the scientific report is displayed on a user interface such as a mobile phone, a tablet, a desktop, a laptop or other smart device.

10. The system for monitoring and tracking the recovery of an individual undergoing physiotherapy as claimed in claim 1, wherein exercise protocol for an individual can be set by a physiotherapist, a medical practitioner, paramedic, or a caregiver.