Design and Realization of a Telerehabilitation application for patients with Shoulder Impingement Syndrome

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i i “output” — 2017/6/10 — 19:28 — page 1 — #1 i i i i UNIVERSIT `A DI PISA SCUOLA DI INGEGNERIA

CORSO DI LAUREA MAGISTRALE IN

INGEGNERIA BIOMEDICA

Design and Realization of a Telerehabilitation

application for patients with Shoulder Impingement

Syndrome

Relatori

Candidato

Alessandro Tognetti

Maria Bellizzi

Federico Lorussi

Nicola Carbonaro

16 Giugno 2017

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Abstract

The aim of the present work is to develop a digital application, which in-cludes a rehabilitation protocol for the treatment of Shoulder Impingement Syndrome (SIS) and a standard shoulder evaluation test to check the actual functional level and the progress achieved through training. The use of a wearable sensing technology permits accurate and reliable measurements of the shoulder motion parameters, which can be delivered to clinicians in order to supervise the rehabilitation activities, to avoid injuries due to improperly performed exercise. A clear, familiar and usable graphic user interface (GUI) has been developed, allowing physicians to adjust and optimize the training protocol, in terms of type, duration and intensity of the exercises, enabling to take into account the specific needs and goals of the patient. The final purpose is to facilitate the functional recovery and maintenance of the phys-ical level gained through the rehabilitation program, allowing for a complete return to sport and ordinary activities.

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A.1 The Bones of the Shoulder Girdle . . . I A.1.1 The clavicle . . . II A.1.2 The scapula . . . III A.1.3 The humerus . . . V A.2 The Joints of the Shoulder Girdle . . . VII A.2.1 The sternoclavicular joint . . . VIII A.2.2 The acromioclavicular joint . . . VIII A.2.3 The glenohumeral joint . . . IX

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List of Figures

1.1 The shoulder girdle - Posterior View . . . 9

1.2 The shoulder girdle - Anterior View . . . 10

1.3 Abduction of the arm at 90◦ . . . 11

1.4 The subacromial space . . . 12

1.5 Acromion types . . . 15

1.6 Forces involved in the abduction of the arm . . . 17

1.7 Conservative treatment algorithm for SIS . . . 24

2.1 Telerehabilitation supervision . . . 32

2.2 Wearable devices . . . 42

2.3 Scheme of an Inertial Mass Unit . . . 44

2.4 The challenge of big health data . . . 48

3.1 Planes of motion . . . 50

3.2 Bi-articular model System of Reference . . . 53

3.3 Reconstruction of trochlea position . . . 55

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3.7 The Awinda station . . . 59

3.8 MT Manager: real-time data visualization . . . 60

3.9 MTw Coordinate System . . . 62

3.10 Matlab and VRML Coordinate systems . . . 64

3.11 Hierarchical tree structure of VRML dumbbell . . . 65

3.12 ShoulPhy virtual world . . . 66

3.13 VR Sink Parameters . . . 68

3.14 Simulink and VR Sink connection . . . 69

3.15 Creation of a UI with GUIDE . . . 70

4.1 ShoulPhy key features . . . 76

4.2 ShoulPhy workflow map . . . 77

4.3 ShoulPhy: main screen . . . 78

4.4 Admin session . . . 79

4.5 Exercise creation . . . 80

4.6 Registration procedure . . . 81

4.7 Sensors arrangement . . . 82

4.8 Calibration procedure . . . 83

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LIST OF FIGURES

4.10 Constant Murley Shoulder test . . . 85

4.11 Exercises library . . . 85

4.12 Simulink model for real-time monitoring . . . 86

4.13 The gym virtual environment . . . 88

4.14 3D virtual humanoid reproducing subject motion. . . 89

4.15 Constant Murley Score . . . 91

4.16 Level selection . . . 93

4.17 Standard exercise screen . . . 97

4.18 Example of video tutorial created . . . 98

4.19 Power strength exercise . . . 99

4.20 Countdown visualization . . . 100 4.21 Visual feedback . . . 103 4.22 Exercise 1 score . . . 105 4.23 Exercise 2 score . . . 106 4.24 Exercise 3 score . . . 108 4.25 Exercise 4 score . . . 109 4.26 Data storage . . . 110 4.27 Calibration worksheet . . . 110 4.28 Exercise worksheet . . . 111

A.1 The Clavicle . . . II A.2 Tha scapula . . . IV

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List of Tables

1.1 SIS structural factors . . . 14

1.2 SIS functional factors . . . 16

4.1 Beginner level: typical exercise . . . 94

4.2 Intermediate level: typical exercise . . . 95

4.3 Advanced level: typical exercise . . . 96

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Introduction

Musculoskeletal disorders (MSDs) of the shoulder are common, with as many as 30.3% of adults experiencing shoulder pain annually, with significant economic impact. The most common shoulder disorder in general practice is Shoulder Impingement Syndrome (SIS), which is caused by a compression of some of the rotator cuff tendons, most prominently the supraspinatus ten-don, along with the other soft structures, such as the long head of the biceps, the bursa and the ligaments in the subacromial space. SIS accounts for up to 48% of all consultations for shoulder pain, within primary care. Repetitive activities, involving the use of the upper arm at or above the shoulder level, represent the primary risk factor for SIS; the target population is composed by a wide variety of workers, from construction employees, to athletes, who are directly exposed to overhead work conditions, heavy lifting and forceful work, but may include also other categories, performing recreational activi-ties that can be related to SIS. Since the incidence of SIS is increased among people older than 40 years, age is an additional influencing factor, leading

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Introduction

to the degeneration of soft tissues, dysfunctional scapulothoracic and gleno-humeral mechanics and awkward posture. Shoulder Impingement Syndrome is often caused by an imbalance between the muscles involved in the shoul-der motion, such as the deltoideus, the rotator cuff muscles and the scapula stabilizers. The incorrect activation of these muscular groups affects the movements of the shoulder, leading to changes in glenohumeral joint, with strong evidence of a compression of the subacromial space during activities, when arm is elevated closer to an angle of 90◦. Differential diagnosis of this condition remains critical, since it can be very difficult to identify shoul-der impingement relying on very generic symptoms, like shoulshoul-der pain and weakness. Early recognition and subsequent management is crucial to pre-vent the progress of SIS, avoiding the risk of further morbidity to the patient, e.g. a complete rotator cuff tendons rupture. A large variety of treatment options are available depending on the stage of the condition, the patients actual level of activity and the intended goals. Primarily a conservative treatment, tailored on the patient, should be considered in order to reduce pain and inflammation; secondarily, if a conservative management fails to relieve the symptoms, surgery should be warranted, preferring arthroscopic to open surgery. However physical rehabilitation represent a key factor in the therapeutic protocol, to restore the functional level of activity, in pa-tients presenting SIS. The first aim of SIS therapy should be to restore a suitable balance between the forces involved in the shoulder motion in or-2

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Introduction

der to re-establish a correct kinematics and reduce the pain. This goal can be reached firstly by strengthening the scapular stabilisers, which provide a stable skeletal scaffold for the rotator cuff muscles; secondly correcting the imbalance between the internal and external rotators. Thirdly, improving coordination and strength within the total range of motion (ROM) of the shoulder girdle will facilitate the recovery of the functional level necessary to activities of daily living (ADL), or broader goals. According to the Eu-ropean Musculoskeletal Conditions Surveillance and Information Network, the breakthrough in the management of musculoskeletal disorders, e.g. SIS, consists into asserting that patients affected by this condition can actively take part in the management of their physio-care. The main obstacle in the current therapy for SIS is compliance with and motivation to perform the training protocol; this aspect is quite relevant once the patient is discharged from the clinic. Due to the repetitive nature of the tasks, the exercises pro-tocol may results tedious, not challenging and poorly interactive for the pa-tient at home, thus limiting rehabilitation outcomes and functional recovery. Gamification of therapy in the rehabilitation field could be a good strategy to increase compliance and motivation, thanks to the possibility to self-challenge in a highly interactive digital environment, produced by the combined use of virtual reality and wearable devices. In this context the present work has been focused on the development of a custom digital application for Shoul-der Impingement Syndrome Telerehabilitation, named ’Shoulphy’, short for

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Introduction

Shoulder Physiotherapy, which allows for patients evaluation and training in both indoor and outdoor environments. The app, relying on the use of wearable sensing devices and virtual reality, represents a simple, helpful and effective tool for both patients and physicians, in the management of SIS. The aim of this work is to demonstrate the feasibility, usability and the potential effectiveness of Shoulphy App, relying on the inherent advantages related to its use, such as the quantitative outcome of shoulder functionality, the increase of patient motivation due to the gamification approach, the time-continuous follow-up of the patient to avoid the risk of recidives, finally the possibility to create a global database to aid clinicians in diagnosis of SIS. Starting from the design and realisation of the graphical interface, through the GUIDE Matlab toolbox, two user interfaces have been created, in order to be addressed to patients as well as clinicians. Concerning the clinician interface, a smart method for the creation of highly customizable exercises has been implemented, in order to create patient-centered training program for an optimal management of SIS rehabilitation, permitting also the real-isation of video-tutorial, that may result really helpful to make the patient aware of the motor tasks required. Moreover the key feature consists into the possibility of remote monitoring the patient’s activity in real-time, thanks to the implementation of a proper code, permitting the interaction between the Matlab environment, in which the app runs, and the dedicated software that enable the acquisition of data from IMU, and the realisation of a specific data 4

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Introduction

transmission protocol (UDP); this allow to send data to local and remote host, from an optimised set of two wearable inertial sensors, placed properly on the sternum and on the forearm, just before the wrist joint, in order to track the upper-arm motion with respect to the trunk. These data are used to drive a 3D humanoid avatar, inserted in an ad hoc virtual world, recre-ating a gym environment, thus enabling the visualisation of the individual activity. Furthermore ShoulPhy offers the opportunity to check the rehabil-itation outcomes at each training session relying on raw data acquired from IMUs, and 2D graphs, plotting the range of motion over time, comparing the expected and the actual trend performed by the patient. To accomplish the necessity of a standard assessment of patient’s shoulder functionality a digi-tal version of the standard evaluation test, i.e the Constant-Murley Shoulder Test has been implemented and integrated within ShoulPhy App, allowing for the autonomous and quantitative measure of the ROM reached in shoul-der abduction and flexion, through data sensors, as well as the total score. A proper sensor calibration procedure has been made up, and integrated in the application, in order to provide a reliable measure in term of shoulder range of motion. Furthermore, looking forward to figuring out an effective and comprehensive rehabilitation program, the necessity to cooperate with experts in sports science and physiotherapy has arised. Thanks to the col-laboration with Fisiokinetic, a high qualified centre for physiotherapy as well as orthopaedic, sports and neurological rehabilitation, a training program

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Introduction

for SIS patients has been defined, with all the skills and tasks required; the defined program has been created through the clinician’s interface, and inte-grated in Shoulphy App, to evaluate the actual rehabilitation outcomes. In this context two main libraries have been created and included in ShoulPhy App: the first one contains custom exercises suggested by physicians and focused on patient’s goals; the second one includes standard basic exercises from traditional rehabilitation programs for SIS, so giving the patient the possibility to rely on a huge variety of proposed exercises. Moreover a vi-sual feedback has been created and integrated in the real time vivi-sualisation of the selected task, in order to help the patient to correctly perform the exercise and to eventually correct wrong movements in real time. With the aim to realise a gamified approach to the therapeutic training program, a scoring mechanism has been implemented in order to assign virtual awards, depending on the quality of the patient’s performance, increasing patient’s involvement and motivation, with the aim to guarantee the adherence to the rehabilitation program.

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Chapter 1 The Shoulder Impingement

Syndrome

1.1 Preface

Over the past few decades, shoulder impingement syndrome (SIS) has become an increasingly common diagnosis [1]. However, the syndrome was first described in the early 20th _{century. In 1931, Meyer proposed that tears}

of the rotator cuff occurred secondary to attrition, due to friction against the undersurface of the acromion and described corresponding lesions on the undersurface of the acromion and the greater tuberosity. However, he did not implicate the acromion directly. Codman, in 1934, defined the critical zone where most degenerative changes occur as the portion of the rotator

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1.2 The Shoulder Complex

cuff located one centimetre medial to the insertion of the supraspinatus on the greater tuberosity. Armstrong introduced the term supraspinatus syn-drome. The concept of SIS is attributed to Charles Neer, following his paper published in 1972. Neer described subacromial impingement syndrome as a distinct clinical entity and hypothesised that the rotator cuff is impinged upon by the anterior one third of the acromion, the coracoacromial ligament and the acromioclavicular joint rather than by merely the lateral aspect of the acromion. The supraspinatus tendon is the most commonly implicated rotator cuff muscle in shoulder impingement, since it passes under the cora-coacromial arch. Impingement usually occurs in a critical zone, called im-pingement zone, within the supraspinatus tendon, near its insertion at the greater tuberosity. Before discussing the causes, the evaluation methods and the treatment for SIS it is appropriate to give an overview about the anatomy and biomechanics of the shoulder.

1.2 The Shoulder Complex

The shoulder is constituted by a complex arrangement of bones, ligaments and musculotendinous units, called the shoulder girdle. Its main function is to provide a wide range of motion to the upper extremity, with the ultimate purpose of this mechanism being the placement and full use of the hand. The scapula and the clavicle form the shoulder girdle, constituting the only

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attachment of the upper limb to the axial skeleton; in front, however the up-per end of the sternum, with which the medial end of the clavicle articulates, completes it. The shoulder complex is the most flexible joint in the human

Figure 1.1: The shoulder girdle - Posterior View

body, allowing the arm to place and rotate in a wide range of motion in front, above, to the side and behind the body. It is made up of five joints that func-tion in a precise coordinated, synchronous manner. These five joints can be easily divided into two groups, each consisting of anatomical (or true) and physiological (or false) joints, mechanically linked, so that both groups can simultaneously contribute to the total motion of the shoulder. In the first

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anatomical articulation, and the subdeltoid joint, often called the second joint of the shoulder, that can be considered a physiological joint, consist-ing of one surface glidconsist-ing over another. The second group is composed by three different articulations: the scapulothoracic, the acromioclavicular and the sternoclavicular joints. Shoulder function results from the complex

inter-Figure 1.2: The shoulder girdle - Anterior View

action between muscular, osseous and supporting structures that constitute the shoulder girdle. The study and the comprehension of the biomechanical principles that drive the shoulder motion provide the basis for a successful diagnosis and correct treatment of shoulder dysfunctions and pathologies, e.g. the subacromial impingement. For further details about the functional 10

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1.3 Classification

anatomy of the Shoulder girdle, refer to Appendix A.

1.3 Classification

The shoulder impingement, also known as subacromial impingement, refers to a mechanical process, in which the supraspinatus tendon of the rotator cuff undergoes repetitive compression and micro trauma, as it passes under the coracoacromial arch [2]. When the arm is elevated, rotator cuff impingement may occur; it is most susceptible to occurr at 90◦ of abduction, when the scapula has not rotated upward adequately to ensure the rotator cuff does not impinge on the acromion and coracoacromial ligament [3, 4]. Humeral rotation also influences impingement during forward flexion, as

dur-Figure 1.3: Abduction of the arm at 90◦

ing internal rotation, the greater tubercle encroaches on the acromion, the coracoacromial ligament, and possibly the coracoid process; however, if the humerus is externally rotated, the greater tubercle is rotated from the acro-mial arch and can be elevated without impingement [5]. Impingement can

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1.3 Classification

also occur during horizontal adduction, as the head of the humerus approx-imates on the coracoid process [2]. The subacromial space, as already said in the previous paragraph, is bordered superiorly by the acromion, acromio-clavicular joint, and coracoacromial ligament and measures approximately 5−10 mm from the humeral head. The supraspinatus tendon is the

struc-(a) Anterior View (b) Coronal Section

Figure 1.4: The subacromial space

ture most likely to be involved in impingement syndrome. The diminished vascularity of the tendon has long been proposed to be a contributing factor in the development of subacromial impingement. Codman first observed a hypovascular critical zone just proximal to the insertion of the supraspinatus tendon in 1934. However, further studies have shown signficant blood flow in the critical zone that is no more avascular than other parts of the rotator cuff; it is rather a zone of anastomoses between the osseous vessels (anterior and posterior humeral circumflex) and tendinous vessels (suprascapular and

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1.3 Classification

subscapular). Although now it is accepted that the rotator cuff is not avas-cular, it has been reported that the blood flow is dependent on arm position. In addition, it has also been reported that the vascularity to the rotator cuff diminishes with age [6]. Subacromial impingement can occur through a vari-ety of mechanisms and can be a result of either structural and/or functional contributing factors. Neer outlined three progressive stages:

• Stage I is characterized by edema and haemorrhage of the subacromial bursa. Stage I usually occurs in younger patients, typically younger than 25 years; these patients present with an aching discomfort caused by inflammation of the supraspinatus tendon and long head of the biceps brachii. This stage is reversible with conservative treatment. • With continued insult, stage II develops; it is identified by permanent

histologic changes of fibrosis and tendinosis of the affected tendons and subacromial bursa that cause pain with activity. At this stage patients, usually are 25−40 years old.

• If allowed to progress, stage III develops, with either a partial or com-plete rupture of the rotator cuff and biceps tendons as well as associated pathologic changes in the acromion and acromioclavicular joint. Stage III is not commonly seen in the general population younger than 40 years. However, in overhead athletes or workers may progress through

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1.4 Etiology

pathology at an earlier age, than usual. If left untreated for long peri-ods, these shoulders may undergo chronic arthritic changes caused by unopposed superior migration of the humeral head into the acromion, a process known as cuff tear arthropathy [7].

1.4 Etiology

There are numerous potential functional causes leading to subacromial impingement. A classification widely used in literature distinguish primary from secondary impingement. Primary impingement relates to a mechanical conflict of the rotator cuff, involving mainly structural factors, illustrated in Table 1.1. Abnormalities in coracoacromial arch structure have been

Table 1.1: SIS structural factors

Bursae Inflammation, Thickening;

Rotator cuff tendon Tendinitis, Thickening, Partial-thickness tears; Humeral head Congenital abnormalities, Fracture malunion; Acromioclavicular joint Joint abnormalities, Sprains, Degenerative spurs; Acromion Abnormal shape, Spurs, Os acromiale (unfused),

Malunion of fracture, Nonunion of fracture.

shown to be predictive of the presence of impingement syndrome. Neer noted that individual variations in the shape or slope of the acromion might affect the progression of impingement lesions. Bigliani studied the shape of the acromion to determine the relationship to full-thickness tears of the rotator cuff. The overall incidence of full-thickness tears in this elderly population

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1.4 Etiology

was 34%. Three types of acromion were identified: • Type I: flat;

• Type II: curved; • Type III: hooked.

Figure 1.5: Acromion types

The type III acromion was present in 70% of patients with rotator cuff tears; whereas only 3% of type I acromion was associated with a tear. The findings of this study established a correlation between the type III acromion and rotator cuff tears and confirmed the importance of the supraspinatus outlet radiographic view for evaluation of the acromion [8]. However it can-not be determined whether the acromial shape is caused by or results from a cuff tear [9]. Other investigators have demonstrated a significant corre-lation between a hooked morphology and decreased Constant-Murley score [10]. Studies have investigated the slope of the acromion. Aoki and co-workers have developed a technique for measuring the acromial slope, using the supraspinatus outlet view of the scapula. Their investigation of skeletal

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1.4 Etiology

shoulders has revealed that a flatter acromial slope may be associated with the presence of a spur and a narrowing of the supraspinatus outlet. When applied clinically, patients with stage II impingement compared with normal patients had a significantly flatter acromial slope [11]. Secondary impinge-ment is usually associated to functional causes, such as repetitive overhead activities, leading to GH instability, as reported in Table 1.2. Capsular

mo-Table 1.2: SIS functional factors Rotator cuff Weakness, Inflammation, Imbalance,

Poor dynamic stabilization;

Capsular Capsular: Hipomobility, Hypermobility; Scapular Factors

Postural adaptations, Position,

Restriction in motion, Neuromuscular control,

Paralysis, Fascioscapulohumeral muscolar dystrophy.

bility impairments, increased laxity of the glenohumeral capsule may limit the ability of the capsule to restrain the accessory motions of the humeral head during active movements, thereby causing impingement [12]. Harryman et al demonstrated excessive humeral head superior migration in the presence of posterior capsule tightness. Abnormal scapula position has been described as a source of glenohumeral dysfunction [13]. Abnormal scapula motion that occurs during active movements is referred to as scapular dyskinesis and can predispose the patient to shoulder impingement [14]. Postural deviations (such as scoliosis or rounded shoulder posture) can influence both thoracic and cervical spine orientation and both resting and dynamic scapula position. Last, an inefficient rotator cuff can predispose an individual to subacromial 16

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1.4 Etiology

impingement. The primary function of the rotator cuff is to stabilize the humeral head and maintain its position in the central aspect of the glenoid cavity. However, if weakness is present in the rotator cuff, contraction of the deltoid (primarily at lower abduction angles between 0◦ and 45◦ will cre-ate a superior shear of the humeral head, causing impingement against the coracoacromial arch. It is generally accepted that the rotator cuff muscles and the deltoid are primary movers of GH abduction, as showed in Fig.1.6. These two muscular groups contribute equally to torque production in

func-Figure 1.6: Forces involved in the abduction of the arm

tional planes of motion. With the arm at the side the deltoid force direction results almost vertical (red in Fig.1.6 A), thus causing a superior shear force of the head of the humerus that, if unopposed because of the muscular im-balance due to the weakness of the rotator cuff (blue in Fig.1.6 B), might

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1.4 Etiology

pingement of subacromial soft tissues (Fig.1.6 C). The force vectors of the infraspinatus, subscapularis and teres minor muscles results in a compressive component, as well a rotational force. Their action consists into stabiliz-ing the head of the humerus at the center of the glenoid fossa, allowstabiliz-ing the deltoid and the supraspinatus to act as abductors of the humerus (Fig.1.6 D). Further studies demonstrate a poor role of the supraspinatus in the arm abduction, even at the earlier stage of the movement limiting its function as merely synergic of the other rotator cuff muscles, because of the horizontal orientation of the muscular fibers, thus underlying that the deltoid muscle is capable to perform alone a complete abduction [15]. Clinically, the patient can present with multiple causative factors that accumulate to attribute to their pathology. Matsen and Arntz [16] described rotator cuff impingement as a self-perpetuating process, noting the following: muscle or cuff tendon weakness causes impingement as a result of diminished stabilization of the humeral head, which contributes to tendon damage, disuse atrophy, and ad-ditional cuff weakness; bursal thickening causes impingement as a result of narrowing the subacromial space and posterior capsule tightness develops, perpetuating the impingement syndrome.

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1.5 Clinical Evaluation

The multifactorial nature of SIS makes very difficult for the clinicians to make a correct diagnosis of this kind of musculoskeletal disorder; the lack of consensus for diagnostic criteria, clearly represents an obstacle to further investigation on treatment interventions and prognosis. Optimizing the diagnosis of SIS would be a key factor to improve the ability to guide treatment decision-making leading to an improved medical management.

1.5.1 Physical Examination

A complete evaluation, including a thorough history and physical exam-ination, is required for all patients presenting with shoulder pain. Symp-toms suggestive of impingement include pain with overhead activities, such as combing the hair or reaching high shelves. Pain with internal rotation is a common complaint. Night pain while lying on the affected side is also a frequent problem. Patients may locate the pain to the anterior shoul-der or lateral deltoideus, because the subacromial bursa extends beyond the lateral border of the acromion. Overhead athletes with impingement and cuff pathology secondary to subtle anterior instability are usually young and complain of pain and decreased throwing velocity. The physical examina-tion should begin with inspecexamina-tion, looking for abnormal posture and signs of wasting or scapular winging that suggest neurologic injury or entrapment

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[17]. Clinicians can rely on many instruments that are able to measure qual-itatively symptoms and function of the shoulder, to mainly assess the pain sensation, the active and passive range of motion and the total strength. The Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH), together with its short form (QuickDASH), is the most widespread and best-tested and characterized instrument for shoulder assessment. However, it is specific to the arm, not just to the shoulder. The Shoulder Pain and Disability Index (SPADI), the Constant (Murley) Score (CS), and the American Shoulder and Elbow Surgeons (ASES) questionnaire for the shoulder are well char-acterized and accepted in the scientific community. Their responsiveness is comparable. The Constant Murley Score is one of the most used question-naire to obtain a standard evaluation in case of subacromial impingement; it consists of four domains: pain, activities of daily living, mobility (4 items: forward and lateral abduction/elevation, external and internal rotation), and power/strength (1 item). Pain and ADL 1−3 are interviewed from the pa-tient; all other items are examiner assessed. The score spans from 0◦ to 100◦ and it can be interpreted respectively as minimal function to total function of the shoulder. Comparison with the contralateral side is possible. Dif-ferent norm data are available, for eventual comparison with the standard age-based. Clinicians can examine the range of motion of the impinged shoul-der, relying on a wide range of clinical test, including the Neer’s sign, the Hawkins-Kennedy, the Neer’s impingement test, the painful arc, the empty 20

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can (also known as Jobe test), the external rotation resistance test, Yea-gerson, Drop Arm, lift-off. Michener et al. investigated the combination of different tests, in order to confirm the diagnosis and screening SIS, finding that the combination of the painful arc and the external rotation resistance test with the Neer’s test are the best three on a combination of five to screen SIS; while combining them with the Jobe test is very useful to confirm the diagnosis of SIS [18]. Other studies determined the reliability and diagnostic accuracy of these test, which aim is to isolate the muscles involved in the shoulder motion, to assess a differential diagnosis of Shoulder Impingement, often difficult because of the number of conditions that can share the same symptoms of SIS and coexist with it, especially in older individuals [19]. The muscles of the rotator cuff are best isolated with 3 different manoeuvres. To isolate the subscapularis, the patient places his hand behind the back and attempts to push away the examinator’s hand: this manoeuvre is called Lift-off test. The external rotation resistance test is performed with the arms at the sides and the elbows flexed; the examiner resists the patient in ex-ternal rotation of the shoulder. This may be painful or weak with tears of the supraspinatus or infraspinatus. Next, to isolate the supraspinatus, which may be painful with SIS, the patient abducts the arms to 90◦, forward flexes to 30◦, and internally rotates each humerus so that the thums are pointed to the floor. A downward force is then applied to the forearms as the patient resists; this is named empty can test. Two provocative techniques are highly

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sensitive, but not very specific for diagnosing SIS: Neer’s sign elicits pain with maximum passive shoulder elevation and internal rotation while the scapula is stabilized; Hawkin’s sign is painful with passive forward elevation to 90◦ and maximum internal rotation. These two tests have a negative predictive value of greater than 90% when combined. Marked rotator cuff weakness with positive impingement signs may indicate a complete cuff rupture. The Neer Impingement test involves injecting the subacromial space with 10 ml of local anaesthetic and observing a reduction of pain with these provocative tests.

1.5.2 Imaging Techniques

The use of routine imaging studies to evaluate the shoulder girdle for diagnostic purposes can be considered in order to guide treatment decision-making. Standard radiographs, including internal and external rotation an-teroposterior, scapular Y, axillary, and supraspinatus outlet views are impor-tant for the thorough evaluation of shoulder pain. These plain radiographs may demonstrate subacromial spurs, narrowing of the acromiohumeral dis-tance or anomalies of the acromion, being also useful in the differential di-agnosis to show calcifyng tendinitis or fractures. Ultrasound is the most used technique in the evaluation of pathologies related to the rotator cuff, consisting in a sensitive, accurate, inexpensive and non-invasive method to

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1.6 Treatment

confirm a clinical diagnosis of SIS [20]. In the early stages, routine magnetic resonance imaging (MRI) is not recommended. However, if symptoms per-sist MRI could provide details of potential sites of subacromial impingement through the supraspinatus outlet. Ossification of the coracoacromial liga-ment (CAL) or presence of a subacromial spur can be best identified in the sagittal oblique plane; however, differentiation of a pathologic spur and the normal CAL can be difficult. The axial view is good for identifying bicep tendon, while the coronal and sagittal oblique views demonstrate bursitis. Findings that indicate this condition include bursal thickness >3 mm, the presence of fluid medial to the acromioclavicular joint and the presence of fluid in the anterior aspect of the bursa. Typically, MRI is performed with the arm adducted; however, this position does not recreate the position of impingement [21].

1.6 Treatment

The initial management of a patient with subacromial impingement is conservative; studies show that conservative management of the shoulder im-pingement syndrome resolves the problem in 70-90% of patients [22]. Avoid-ance of provocative activities, non steroidal anti-inflammatory drug medi-cation (NSAID), and physical therapy (PT) should be the initial modes of treatment. Several reviews compared the effectiveness of treatments on a

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1.6 Treatment

Figure 1.7: Conservative treatment algorithm for SIS

variety of outcome measures, including pain, range of movement, functional limitations, and return to work. Hence, the conclusion on effectiveness of various treatments was primarily based on the combination of these outcome measures. Desmeules ate al. reported lack of uniformity in defining, evalu-ating and treevalu-ating shoulder impingement [23]. Traditionally, only anecdotal evidence existed regarding steroid injections for the treatment of impinge-ment. Their effectiveness in the short term has now been validated in ran-domized, double-blinded clinical studies. However, the accuracy of injection placement has come into question, since some studies demonstrate that only 70% of injections reach the subacromial space, as verified by bursography[24]. Furthermore, there is little information about the content of the injections and the efficacy of different synthetic steroids. Although there are no

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1.6 Treatment

tative data, it is generally believed that repeated injections should be avoided because of the potentially adverse effects on tendon integrity. The vascularity of the rotator cuff and its influence on the tissues ability to heal are a point of discussion that have led health care professionals to seek alternate ways of augmenting the healing process. Platelet-rich plasma (PRP) is an enriched platelet blood plasma that contains growth factors and other cytokines that stimulate and enhance the body own healing response. Foster et al. reported few controlled clinical trials that have adequately evaluated the safety and efficacy of treatments and concluded PRP to be a promising, but not proven, treatment option for tendon and muscle injuries [25]. The Focused Aspira-tion of Soft Tissue procedure (FAST) has recently gained attenAspira-tion in the treatment of tendon pathology by its ability to ablate diseased tissue. An ultrasound-guided needle is placed on a hypoechoic-identified region of the tendon as the tissue is debrided, emulsified, and aspirated. This technique affords a quicker recovery time, with patients able to typically return to prior level of function in four-eight weeks. There is strong evidence that extracorporeal shock-wave therapy is no more effective than placebo, mod-erate evidence that ultrasound therapy is no more effective than placebo, and limited evidence that laser is no more effective than placebo with regard to functional limitations [26]. Non-operative rehabilitation programs for im-pingement syndrome have been reported in the literature, consisting of rest, rotator cuff and scapula strengthening, and manual techniques, with good

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1.6 Treatment

outcomes. A study by Conroy and Hayes demonstrated less pain in patients, receiving both exercises and manual therapy, compared with participants who performed exercises only [27]. There is a general consensus that a com-prehensive and supervised rehabilitation program is the first line of treatment in SIS [27] [28]; many reviews found strong evidence of its effectiveness as a part of a multimodal program of care. Before starting the therapy program, clinicians should be able to perform a complete and thorough evaluation. to establish an accurate diagnosis, identify all causative factors, and deter-mine the involved structures, implementing a custom treatment program to address these factors and prioritize the treatment goals. The primary goal of the treatment program is to reduce the mechanical conflict to the rotator cuff and promote a restoration in tendon vascularity that can result from SIS. The treatment program should consist in different phases, following a grad-ual progression of exercises and implied stresses that increase and become more demanding than those of the previous phase of treatment. Initially, the patient should be educated about modification and avoidance of activities (such as overhead sports and exercises) and postural awareness with sitting and standing positions to increase subacromial space. Clinically, pain and inflammation can be reduced through the use of local therapeutic modalities such as ice, ultrasound, electrical stimulation, kinesiotaping, and iontophore-sis. Cryotherapy serves as a vasoconstrictor to reduce the metabolic activity, thereby diminishing inflammation [29]. During the acute phase of rehabilita-26

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1.6 Treatment

tion the patient is instructed to perform frequent sessions of active-assisted range of motion (AAROM) and stretching exercises, as this has been shown to reduce pain. The patient should be educated to avoid/minimize activities in which the arm is raised above shoulder height to avoid motions that cre-ate impingement. The patient is also instructed to refrain from resting the arm at the side, instead having the shoulder supported slightly away from his side to allow for increased vascularity to the healing structures. After this first phase the goal of the rehabilitation program should be focused onto improving flexibility, mobility, and ROM of the shoulder joint complex re-store the muscular balance and enhance neuromuscular control. Exercises are performed in a full arc of the patients available range of motion with the aim to promote dynamic stabilization and endurance training of the rota-tor cuff. The program may consider the opportunity to vary the resistance and the speed during the movement and interchange concentric and eccen-tric activity. The program should be aimed to gradually augment power and endurance; plyometric exercises can be scheduled for the last phase of rehabilitation in order to further enhance dynamic stability and propriocep-tion as well as introduce and gradually increase funcpropriocep-tional stresses on the shoulder joint. When the rehabilitation program is completed the patient is instructed to continue training in order to improve upper extremity strength, power, and endurance. Thus,the effective rehabilitation program will focus on regaining full shoulder range of motion, re-establish dynamic rotator cuff

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1.6 Treatment

stability, and implement a progression of resistive exercises to fully restore strength and local muscular endurance in the rotator cuff and scapular sta-bilizers, combined with functional activities or sport specific drills, in case of patient is an athlete, to allow for a complete return to sport and activity.

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Chapter 2 The role of Telemedicine in

Physical Rehabilitation

2.1 The concept of Telerehabilitation

There is great evidence that advancements in medical area led to global population ageing, thus representing a big achievement over disease but also a great challenge, because of the increasing costs for managing healthcare [30]. Technology has a key role to play: actually the digital revolution has led to profound technological, economic and social changes during the past few decades, modifying the perception and the human approach to problems and challenges of everyday life. Up to twenty years ago some of the items and devices that we consider essential in our daily life existed only in the mind

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2.1 The concept of Telerehabilitation

or in the drafts of their inventors, thus giving us a sense of how technology has evolved rapidly, infiltrating in the different spheres of the society and changing the interaction between the man and the world around him. In 1991 in an article entitled “The computer for the 21st century” Mark Weiser [31] wrote:

“The most profound technologies are those that disappear. They weave them-selves into the fabric of everyday life until they are indistinguishable from it.”

The increase in the level of technological innovation,in particular in the biomedical sector, had a significant social impact, allowing for a general improvement in the quality of life, through a qualitative and quantitative increase of services and their accessibility to a growing portion of society. In order to increase access to health care, raising awareness and involving the user directly, we can take advantage of the benefits derived from spreading and fusion of the Internet of Things with our daily lives. Advancements in Information and Communication Technologies (ICT) coupled with the rapid development of software, sensors, robotics, digital medical records, and other equipment have helped telemedicine to develop into a key component in the evolution of modern health care; what is important is not to intend telemedicine merely as a result of ‘technology push’ alone, rather it must be driven by real clinical needs and the desire to improve health care. In this context, a lot of research has recently been directed toward the physi-30

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cal rehabilitation field, bringing to the rise of telerehabilitation as an actual possibility of application and a promising development in the future. In the traditional health care model, rehabilitation consists of daily sessions of ex-ercises carried out with a therapist, who directly supervise the patient in real-time. As the elderly population increases this represents a large and ever-increasing cost for health care providers that cannot be sustained in the long term, hence why new solutions to manage rehabilitation are needed. Telerehabilitation is a subfield of telemedicine consisting of a system to con-trol a rehabilitation program ‘at distance’: this can be achieved by using ICT, as the service delivery medium, to provide rehabilitation services to people remotely in their homes or other environments. By using ICT, client access to care can be improved and the reach of clinicians can be extended beyond the physical walls of a traditional health care facility, thus expanding continuity of care and avoiding the risk of recidives. The concept of telecare empowers and enables individuals to take control of the management of their medical needs and interventions by enabling personalised care, choice and personal control, always under the supervision of a clinicians team. From this perspective telerehabilitation is now recognised as a bridge between the clinicians and the patient [32]. Published studies and current experiences show that telerehabilitation mainly addresses:

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Figure 2.1: Telerehabilitation supervision • patients clinical management at distance;

• management of rehabilitation programs by remote; • selection of the needs of the patient or the caregiver; • tele-consulting;

• education of professionals and caregivers.

According to the World Health Organisation (WHO) MSDs constitute a massive drain on the resources of individuals, health system and social care systems, because of the related direct and indirect costs. However, they also represent a significant opportunity for cost reduction, since they are manageable and can be preventable. Telerehabilitation for musculoskeletal disorders has been studied, and interesting conclusions have been published, asserting the validity, feasibility and effectiveness of ‘in-home telerehabili-tation’ for the assessment and treatment for both upper and lower limbs 32

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2.2 Virtual Reality

[33, 34, 35, 36, 37, 38]. According to Russell et al. a telerehabilitation ap-proach is able to produce functional and physical results, comparable with traditional physical therapy, resulting in a successful and satisfying inter-vention for patients, despite their limited computer skills [39, 40]. Focus-ing on the upper limb, a recent work by Pastora et al. [41] evaluates the feasibility and effectiveness of a customisable telerehabilitation intervention compared with conservative treatment in patients with SIS, after subacro-mial decompression surgery, through a single-blind, prospective, randomised clinical trial.

2.2 Virtual Reality

Virtual reality (VR) is commonly used in many domains because of its ability to provide a standardised, reproducible and controllable environment. In telerehabilitation it can be very useful both for the assessment and ther-apy phases, since it permits to control stimuli presented to patients and thus to accurately evaluate their progress or compare them to different popula-tions in standard situapopula-tions, allowing for the creation of a new generation of rehabilitation tools [42]. Clinicians have studied the potential advantages of incorporating VR technologies into the assessment and rehabilitation of pa-tient training. Some companies even propose off-the-shelf solutions such as CAREN, a versatile, multi sensory system for clinical analysis, rehabilitation,

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2.2 Virtual Reality

evaluation and registration of the human balance system, including sensory inputs like visual, auditory, vestibular and tactile[43]; IREX, short for Im-mersive Rehabilitation EXercise, uses a camera connected to a computer, to place the live real-time, full body image of the patients onto the screen, where they would see themselves immersed in dynamic Virtual Reality video games[44]. Many studies based on VR, range from experiments with 3D pro-jection of objects on a screen up to the immersion of the subject in a multi-sensory feedback environment, under visual, tactile, or auditory stimuli. VR is defined as a scientific and technical domain that exploits computer sci-ences and behavioural interfaces; it consists of simulating the behavior of 3D entities that interact with each other in real time and with users, immersed in a pseudo-natural environment through sensorimotor channels. According to Sanchez et al. a VR system is efficient when the user has the feeling of being there [45, 46], which is the concept of presence in the virtual world [47]. The main advantage, relating to the use of VR in telerehabilitation is the complete control of the stimuli provided to the subject, enabling a stan-dardised and reproducible environment [48]. Moreover the potential ability to have stereoscopic vision, giving the subject salient motion-in-depth infor-mation [49]. Finally the viewpoint of a virtual environment can be adapted in real time to correspond to the subjects one. Thus VR can be considered as a fun training tool increasing the motivation of patients to continue the training program, and making them directly involved in the management of 34

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2.3 Exergames

their physio-care.

2.3 Exergames

One of the most important goal in functional rehabilitation is to recover mechanical functions of the human body. Conventional functional rehabili-tation consists of a therapeutic consulrehabili-tation, followed by the assignment of a training protocol of physical exercises to be performed with or without assistance of the therapist. This approach has showed some practical limi-tations, due to the repetitive and insistent nature of rehabilitation exercises, thus affecting the psychological state of the patient and decreasing the phys-ical performance. Thus, the efficiency of the rehabilitation program depends also on the patients motivation. One of the potential solutions could be to improve the interaction between the patient and the rehabilitation exercise, making it more user-friendly and hence effective. With this purpose, a rapid increase in research has recently been directed toward video games, as a com-plementary tool in home-based rehabilitation systems. The use of gaming technology let patients exercise while playing games that hide the burden of the therapeutic repetitive tasks under the hood of a compelling fantasy, thus providing effective treatment by exploiting the motivational power of games to increase adherence [50]. Several studies focused on exergames in rehabil-itation [51, 52], demonstrating the effectiveness of exergame-based therapy,

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2.3 Exergames

leading to the intrinsic motivational benefits. The role of the therapist is crucial to assert the patient safety and efficacy of the rehabilitation protocol; thus the combination of motivational content, to overcome the tediousness of a traditional therapeutic training session, together with the capability to deliver personalised therapeutic protocols could be the key to provide au-tonomous rehabilitation in home-environment. A few attempts were made in using commercial exergames for autonomous rehabilitation at home [53, 54]. SeeMeTM_{was one of the first serious game,introduced to provide user-friendly}

tutorials for functional rehabilitation; Reflexion Health has developed the first project focusing on the use of Microsofts Kinect system to track pa-tient adherence to the prescribed rehabilitation plan as well as to customize treatment to each patient and to assert progress during follow-up. Recently, Jintronix also proposed a complete system of rehabilitation using Microsofts Kinect and the possibility for the therapist to choose the appropriate exer-cises. Nintendo released the Wii Fit platform, including a built-in centre of pressure sensor that, according to a study by Fu et al., can enhance training on balance control to reduce the incidence of falls in frail elderly persons living in a nursing home. The system offers feedback to the participants, enabling them to identify improved balance capabilities [55]. A recent pi-lot study revealed that a structured Wii protocol could be a viable adjunct for improving pain, disability, quality of life and pain-free active ROM in patients with SIS [56]. Indeed commercial exergames, made primarily for en-36

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2.3 Exergames

tertainment and fitness, not always succeed into addressing the whole range of requirements of a rehabilitation therapy. In fact, commercial exergames integrate into their gameplay the primary goals of an exercise, which are translated into game actions, but they do not always address the secondary goals of an exercise, i.e. the specification of how an exercise should be car-ried out. This is important in rehabilitation, since therapists not only assign exercises, but also supervise, recommend and correct the patient, while exer-cising. Without this supervision activity, exercising could possibly be more harmful than helpful due to wrong postures and joint overloading [53] [57]. Although the term exergame has become widespread, its definition is still fuzzy. An exergame has a dual nature: it is both an exercise and a game, but it is not easy to clearly separate the two aspects. To analyse the rela-tionship between the game and the exercise it can be proper to start by their definition. Exercise is a physical activity that is planned, structured, and repetitive for the purpose of conditioning any part of the body. A game is a system in which players engage in an artificial conflict, defined by rules, that results in a quantifiable outcome. These definitions have a point in common: an exercise is structured, while a game is defined by rules. The two con-cepts can be assimilated. Of the two, especially while treating therapeutic exergames, the exercise structure must clearly have priority, as the main goal in rehabilitation must be to provide valid exercises, and only then to provide entertaining games. Thus an exergame can be easily defined as an exercise

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2.3 Exergames

with a game built into its structure that supports all primary and secondary goals needed for the success of therapy. This highlights the priority of the exercise over the game, which should not interfere with the correct execution of the exercise: this means that the exergame, when stripped of its gaming parts, should still work as a valid exercise. In a therapeutic exergame, pri-mary goals can be easily merged into the game play, while secondary goals, such as movement correctness or compensatory motion prevention, can be addressed separately, although they should still provide feedback to the user. A suitable methodology to design effective and safe therapeutic exergames has been recently proposed by Pirovano et al., based on a four-step procedure: 1. Exercise definition: starting from a therapy goal, a set of coherent ex-ercises that covers all the needs of the therapy is chosen. Each exercise is properly structured in terms of primary and secondary goals;

2. Virtualization: the primary goals of the exercise are implemented into a virtual exercise (VE) by defining input (tracking) and output (feed-back) requirements through simple graphical elements and by specify-ing interaction mechanisms;

3. Game design: the VE is then transformed into a true exergame by adding all gaming elements;

4. Secondary goals: the secondary goals of the exercise are handled sepa-rately, finally achieving a therapeutic exergame.

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2.3 Exergames

For each exercise, input parameters, such as amplitude, speed of motion, number of repetitions should be provided to define movement properties, de-termining the degree of challenge of the exercise itself, whose difficulty should be oriented to patient needs. Moreover, a set of outcome parameters has to be defined for both patient and therapist: in the first case it can be useful to give a qualitative output to make the patient conscious of his performance in term of success rate, reaction time and progress in reaching the primary goals of the exercise. The motivational aspect can be achieved through a proper use of verbal praise, by implementing scoring mechanisms and vir-tual reward systems [58] [59]. Concerning the secondary goals, that measure how correctly the exercise is performed a good idea is to provide a real-time feedback to the patients who can correct themselves while exercising. Feed-back on wrong movements can be easily provided by changing the colour of a guide object in the virtual environment: i.e. changing the colour from green (correct movement), to yellow, orange, and red, depending on severity will allow for an intuitive and smart feedback, permitting to identify in real-time the wrong movement and to correct it. From the clinician side, a proper set of outcome measures will allow for a quantitative evaluation of the patients performance in term of both primary and secondary goals. To achieve max-imum effectiveness, the definition of the exercises should be carried out in strict collaboration with the therapists, who have the task to identify the goals and clearly define them, so that the final description of the exercises

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2.4 Wearable Devices

can be used as a technical document for implementation. The exergame mo-tivational factor can be further increased by taking into account the intrinsic ‘fun factors’ [60]. Challenge, fantasy, curiosity, sensation, high interactivity level and social play can be useful, in order to implement a final exergame that meets all therapy requirements, while actively involving the patient in his own physio-care process.

2.4 Wearable Devices

There is a general consensus that the future healthcare system should be preventive, predictive, preemptive, personalised, pervasive, participatory, pa-tient centred, and precise, i.e., p-health system. Health informatics, which is an emerging interdisciplinary area to advance p-health, mainly deals with the acquisition, transmission, processing, storage, retrieval, and use of different types of health and biomedical information [61]. Evolution of sensing tech-nologies has allowed for the development of clothing and small gadgets based wearable devices, with integrated circuits, which can represent the key to bring innovative solutions, in order to achieve early prevention and effective patient-centric care. The main issues to be addressed for the use of wearable technologies can be summarised as ‘SUPER MINDS’ (i.e., Security, Unob-trusiveness, Personalisation, Energy efficiency, Robustness, Miniaturisation, Intelligence, Network, Digitalisation, and Standardisation) [62]. There is a

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clear trend that the devices are getting smaller, lighter, and less obtrusive and more comfortable to wear. Miniaturization and unobtrusiveness can enhance the comfort of using wearable devices, and thus increasing the compliance for long-term and continuous monitoring [63]. Networking is an integral part of wearable devices to deliver high-efficiency and high-quality healthcare ser-vices [64]. The term ‘body sensor network’ (BSN) was coined to address several allied technologies that sustain the development of pervasive sensing for healthcare, wellbeing, sports, and other applications that require ubiqui-tous and pervasive monitoring of physical, physiological, and biochemical pa-rameters in any environment and without activity restriction and behaviour modification. Related to networking, technical challenges include user mo-bility, network security, multiple sensor fusion, and communication protocols for energy-efficient transmission [65]. Energy-efficiency is a crucial element of a wearable device that directly affects the design and usability of the device, especially for long-term monitoring applications. Digitalization is necessary to enable data analysis and storage after acquiring the analog signals from the body with wearable devices. Standardization is a crucial component of any commercial wearable devices, as it ensures the quality and enables inter-operability among devices. On the other hand, personalisation of wearable devices is also important. Apart from personalising the design, it can be more properly referred to personalising the sensor calibration, disease detection, medicine, and treatments. Although physiological measurement devices have

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been widely used in clinical settings for many years, some unique features of unobtrusive and wearable devices, due to the recent advances in sensing, networking and data fusion have transformed the way that they were used. First, the wireless connectivity together with the widely available Internet infrastructure, provide real-time information, that can be useful in monitor-ing daily activities remotely. In addition, unobtrusive and wearable devices can provide detailed quantitative information, since they can closely track their activities, allowing for the detection of eventual health risks, due to wearing activities or wrong movements and facilitate the implementation of preventive measures at an earlier stage. According to many studies a device

Figure 2.2: Wearable devices

that can monitor subjects activity at home can potentially assist in a faster rehabilitation. A cost effective wearable sensor system, that has the same reliability as the gold standard of an optical tracking system, would aid in

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the rehabilitation treatment of subjects affected by musculoskeletal disor-ders, such as SIS. Moreover an unobtrusive device that can be worn outside the clinic, both indoor or outdoor, would provide better monitoring of the individuals adherence to physiotherapy protocol, overcoming the rigid con-straints of a camera-based system, first of all a fixed environment. Finally this device could be a commercially available system, the patients already owns and uses for general purpose, in order both to increase familiarity and usability of the device, since there is no need to acquire a know how about complex technologies, and to limit the costs of the therapy; this device e.g. a smartphone, a smartband or a smartwatch, could be potentially used to register, during a telerehabilitation session in a free environment, relevant biomechanical parameters associated with SIS.

2.4.1 Inertial Measurement Units (IMU)

Real-time human motion tracking has been applied to many applications in biomedical areas: clinical gait analysis, exercise rehabilitation, fall detec-tion, biomechanical analysis of joints. Several tracking technologies, such as mechanical tracking, magnetic tracking and visual tracking have been avail-able for years. However, these tracking technologies lack the capability of tracking in free-living environments. Instead inertial sensors can track hu-man motions in daily life with less intrusion. Software packages are used to

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read the signals collected by the sensors and provide feedback to the user on what the system measures. Typically, these systems are validated against the gold standards, which are considered to be the best known instruments available to perform the desired operation, such as an optical tracking sys-tem [66], that relies on optical cameras that track the movements performed by a subject, while wearing markers, located on precise anatomical repere, thus permitting the reconstruction of body segments. Inertial Measurement Units (IMU) rely upon microelectronic mechanical systems (MEMS) gyro-scopes and accelerometers. Accelerometers are sensors that pick up changes

Figure 2.3: Scheme of an Inertial Mass Unit

in acceleration, basing on a mechanical sensing unit, which consists of a test mass attached to a mechanical suspension system with respect to a fixed ref-erence frame. Inertial forces cause the mass to deflect, enabling an electrical measure of the acceleration from the impact of the test mass with respect to the reference frame. Gyroscopes are devices used to measure the rotation around one or more axis in question. Gyroscopes and accelerometers, can be

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combined together to measure rotational velocities and inertial forces. Al-ternatively, MEM magnetometers can also be integrated in IMUs to provide absolute orientation. These devices are so called magnetic and inertial mea-surement units (MIMUs). In MIMUs, a triaxial accelerometer provide the device a reference gravity vector and pose orientation. Furthermore, a tri-axial gyroscope, provide the device, measurements of rotational movement. Finally, a triaxial magnetometer provide the north reference vector for sen-sor absolute orientation and compensate for gyroscopes drift. The axes of the sensors (accelerometer, gyroscope and magnetometer) are aligned with one another, while the axes of each sensor are orthogonal to one another. A Kalman filter is responsible for fusing the data to estimate the sensor orien-tation changes, so that basing on the initial gravity,the north vector and the Kalman filter output, the sensor can track its current absolute orientation. IMUs and MIMUs are one of the most investigated alternatives in the de-velopment of wearable sensors systems for body motion tracking. Different studies report their use with satisfactory results in biomechanics and clinical situations [67] [68], as well as in movie animation, virtual reality and military navigation [69]. The reasons for such interest on IMUs and MIMUs are the unmatched capabilities that these sensors provide: self-contained 3D body motion tracking with high accuracy, at low cost, small size and weight, low latency and low jitter.

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2.5 Big data

The development of sensing technology has largely increased the capa-bility of sensors to acquire data, and multiple informations are expected to provide different viewpoints of the health status of the patients. Data fusion represents a great challenge because heterogeneous data need to be processed in order to generate unified and meaningful conclusion useful for clinical di-agnosis and treatment [70] [71]. Data fusion is defined as a “multilevel, multifaceted process handling the automatic detection, association, corre-lation, estimation, and combination of data and information from several sources” [72]. Data fusion constitutes an effective method for translating the information from multiple sources into a structured representation, so that human or eventually automated decision can be made accurately. A further step involve the integration of sensing data with other health data, including anamnesis, medication, laboratory test, surgery, imaging data and narrative reports that provide context information for diagnosis and therapy. Electronic health record (EHR) transform these health data in a computer-readable form, assisting clinicians to make appropriate health-care decisions and interventions on individual patients, following the trend analysis of the health-care status of the individual patients [71] [73]. With the increasing number of sensing modalities and low cost sensing devices becoming more accessible to wider populations, such as smartphones or tablets, the amount

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2.5 Big data

and variety of health data have increased rapidly, health data are therefore considered as big data. Based on the 4 V definition of big data by Gartner, i.e., volume, velocity, variety and value, the features of health data can be summarized as 6 V: vast, volume, velocity, variety, value, variation. Vast is the core feature of health data, i.e., the volume, velocity, variety, value and variation are vast. Volume refers to the size of the information. Because health data are collected from over a huge amount of people simultaneously, the velocity of the collection of health data can be extremely high. A variety of health data such as biomechanical parameters, medical imaging and sur-gical reports could be available, thus representing a key source for clinicians to obtain a correct diagnosis and an effective and patient centred therapy. Since the intrinsic nature of the human being is dynamic and evolving, the health data must also be variational. Due to the ongoing developments of network, mobile computing and computer storage, the storage and retrieval of big health data have attracted great attentions. With the increasing use of various kinds of long-term monitoring devices, there is an urgent demand for the intelligent management of big health data. A large number of cloud-based storage and retrieval systems are emerging in recent years. Through outsourcing the big health data, storage-as-a-service is an emerging solu-tion to alleviate the burden and high cost of large local data storage. Some new storage strategies have been proposed, such as storage consolidation and virtualization to optimize the trade-off between computation and storage

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ca-2.5 Big data

pacity [74]. Retrieving specific information from the cloud-based health data is also very challenging. Up to date, a number of healthcare applications based on cloud computing technology have been reported, such as storage and management of EHRs [75] or automatic health data collection in health care institutions [76]. In telerehabilitation, the use of digital applications

Figure 2.4: The challenge of big health data

can be an essential tool both to deliver therapeutic protocols remotely and to acquire functional data, e.g. biomechanical parameters, relevant to the clinical condition, such as the SIS. The informations are collected by mobile devices and can be transmitted wirelessly to a remote centre for storage and analysis. Hence the actual challenge is to merge all these information in a global cloud database, to be accessed by clinicians, that can share their medical experience, in order to provide a reliable tool for supporting clinical decision and address patient centred treatment; thus offering an optimised public health service, crucial for the management of MSDs e.g. SIS.

Design and Realization of a Telerehabilitation application for patients with Shoulder Impingement Syndrome

CORSO DI LAUREA MAGISTRALE IN

INGEGNERIA BIOMEDICA

Design and Realization of a Telerehabilitation

application for patients with Shoulder Impingement

Syndrome

Relatori

Candidato

Alessandro Tognetti

Maria Bellizzi

Federico Lorussi

Nicola Carbonaro

16 Giugno 2017

Contents

List of Figures

List of Tables

Introduction

Chapter 1

The Shoulder Impingement

Syndrome

1.1

Preface

1.2

The Shoulder Complex

1.3

Classification

1.4

Etiology

1.5

Clinical Evaluation

1.5.1

Physical Examination

1.5.2

Imaging Techniques

1.6

Treatment

Chapter 2

The role of Telemedicine in

Physical Rehabilitation

2.1

The concept of Telerehabilitation

2.2

Virtual Reality

2.3

Exergames

2.4

Wearable Devices

2.4.1

Inertial Measurement Units (IMU)

2.5

Big data